{
  "name": "JAEV Notes and Editorial archive",
  "description": "Every published JAEV Note and Editorial text on generative art, computer art, plotters and the history of art made with code, with dates, sources and Wikidata links.",
  "publisher": {"name": "JAEV", "url": "https://jaev.gallery/", "place": "Lund, Sweden"},
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "licenseNote": "JAEV's own text is CC BY 4.0: free to use, quote and build on, with credit to \"JAEV, jaev.gallery\" and a link to the page. Quotations and images by others keep their own terms (see each item's sources and image credit).",
  "corrections": "info@jaev.gallery",
  "generated": "2026-10-29",
  "counts": {"notes": 79, "editorial": 15},
  "items": [
{"type": "note", "title": "10 PRINT CHR$(205.5+RND(1)); : GOTO 10", "url": "https://jaev.gallery/notes/ten-print-maze/",
   "description": "10 PRINT CHR$(205.5+RND(1)); : GOTO 10 is a one-line Commodore 64 program that draws a random maze. What each part does and where it came from.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "10 PRINT CHR$(205.5+RND(1)); : GOTO 10 (book)", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q130327570"}], "mentions": [{"name": "Commodore 64", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q99775"}, {"name": "Nick Montfort", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q7027563"}, {"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}],
   "sources": [{"title": "“10 PRINT CHR$(205.5+RND(1)); : GOTO 10”. 10print.org", "url": "https://10print.org/"}, {"title": "Nick Montfort, Patsy Baudoin, John Bell, Ian Bogost, Jeremy Douglass, Mark C. Marino, Michael Mateas, Casey Reas, Mark Sample and Noah Vawter, 10 PRINT CHR$(205.5+RND(1)); : GOTO 10. MIT Press, 2012. Free PDF, CC BY-NC-SA 3.0", "url": "https://10print.org/"}],
   "related": {"notes":["truchet-tiles","sha-256-as-random-source","vera-molnar-interruptions","sol-lewitt-instructions-as-algorithms"],"editorial":["casey-reas","vera-molnar","generative-art"],"exhibitions":["content"]},
   "image": {"url": "https://jaev.gallery/assets/notes/ten-print-maze-commodore-64-screen.jpg", "alt": "A Commodore 64 screen: a light blue border around a dark blue field filled with light blue diagonal lines that join into a maze-like pattern.", "credit": "A Commodore 64 running 10 PRINT CHR$(205.5+RND(1)); : GOTO 10. Screenshot: Thomas Winningham, CC BY 3.0, via Wikimedia Commons."},
   "text": "10 PRINT CHR$(205.5+RND(1)); : GOTO 10 is a one-line program in the BASIC language of the Commodore 64 home computer. It fills the screen with diagonal lines, each leaning left or right at random, which together look like a maze. The same line is the title of a book about the program by ten authors, published by MIT Press in November 2012.\n\nWhat each part does\n\n10 is the line number, and GOTO 10 jumps back to it. The program repeats forever, until it is interrupted.\n\nRND(1) returns a number between 0 and 1.\n\n205.5+RND(1) is therefore between 205.5 and 206.5. CHR$ needs a whole number and rounds down, so the result is 205 or 206, each with a probability of one half. The program flips a coin without an if.\n\nCharacters 205 and 206 in the Commodore 64's character set, PETSCII, are the two diagonals ╲ and ╱.\n\nPRINT … ; The semicolon makes the next character appear directly after the previous one, with no new line. Without it, the diagonals fall down the left edge in a single column and no maze appears.\n\nThe text screen is 40 characters wide and 25 high, 1,000 characters in all. Characters appear from left to right and top to bottom; when the screen is full, the image scrolls up and printing continues.\n\nThe randomness is not quite random. Called right after the computer is switched on, RND(1) always returns the same first number, 0.185564016, and the same sequence after it. Run first thing, the program draws the same maze on every Commodore 64.\n\nNew drawing\nThe program re-drawn in JavaScript by JAEV: a 40 × 25 grid, one coin flip per cell, filled in reading order. It does not scroll, uses no Commodore 64 colours or character shapes, and takes its chance from JavaScript rather than from Commodore BASIC's RND, so it never repeats the C64's first maze. Code CC BY 4.0.\n\nWhere it came from\n\nThe first printed version was in the Commodore 64 User's Guide of 1982, as three lines that clear the screen and then loop over PRINT CHR$(205.5 + RND(1));. A one-line version numbered 8 appeared in the magazine RUN in 1984. The exact line in the title is not a transcription of either: the book's authors wrote it to combine the common features of the variants they had found.\n\nIs it a maze?\n\nNot necessarily. Nothing in the program guarantees a way through. The book includes a further BASIC program, \"Maze Walker\", that tests whether a given maze has a path from one side to the other.\n\nThe book also traces the pattern back before computers: to the tiles described by Sébastien Truchet in 1704, which Cyril Stanley Smith arranged at random in 1987 (see Truchet tiles), and to Vera Molnár's collage Quatre éléments distribués au hasard (1959). One of the authors is the artist Casey Reas.\n\nJAEV's Content works on the same principle, a fixed rule and a source of chance, but takes its chance from a hash of the day's text instead of a random number generator; see a hash as the source of chance."},
{"type": "note", "title": "AARON's rules (Harold Cohen, 1970s)", "url": "https://jaev.gallery/notes/aaron-rules/",
   "description": "Harold Cohen's AARON drew with if-then rules, frequencies and a map of used space. His own 1979 description of the rules, and a small reconstruction.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "AARON", "type": "Thing", "sameAs": null}], "mentions": [{"name": "Harold Cohen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92723"}],
   "sources": [{"title": "“Harold Cohen: AARON”, 3 February – 19 May 2024. Whitney Museum of American Art, New York", "url": "https://whitney.org/exhibitions/harold-cohen-aaron"}, {"title": "Harold Cohen, “What is an Image?”. Invited paper, 6th International Joint Conference on Artificial Intelligence, Tokyo, 1979", "url": "https://www.aaronshome.com/aaron/publications/whatisanimage.pdf"}, {"title": "Harold Cohen, Bibliography. aaronshome.com", "url": "https://www.aaronshome.com/aaron/bibliography"}],
   "related": {"notes":["sol-lewitt-instructions-as-algorithms","georg-nees-schotter","vera-molnar-interruptions","ten-print-maze"],"editorial":["harold-cohen","the-rule-is-the-work","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/aaron-rules-jaev.jpg", "alt": "Scattered freehand-looking figures in black line on warm paper: rounded closed shapes, some hatched with parallel or crossed lines, one with a smaller shape inside, and open zigzag lines between them.", "credit": "Reconstruction by JAEV after Harold Cohen's 1979 description of AARON's rules: closed and open figures placed in free space, some shaded or given a form inside, lines that veer towards points. Not Cohen's program or a drawing by AARON. CC BY 4.0."},
   "text": "AARON was a drawing program written by the painter Harold Cohen (1928–2016), who conceived it in the late 1960s at the University of California, San Diego, and named it in the early 1970s. It drew by following rules of the form if these conditions hold, then do this. Cohen printed several of them in \"What is an Image?\", a paper written in December 1978 and given in Tokyo in 1979. This note describes those rules as he did and runs a small reconstruction.\n\nA system of rules\n\nIn 1978 the program had \"about three hundred productions\", or rules. The left part of each rule tested \"combinations of up to five or six conditions\"; the right part carried out actions, one of which could pass control to another level of the program.\n\nThe levels were ARTWORK, which decided how to start and when the drawing was finished; MAPPING, which found and allocated space; PLANNING, which developed each figure; and LINES, SECTORS and CURVES, which turned a planned line into movements of the pen. In Cohen's words, \"no single part knows what the drawing should turn out to be like.\"\n\nThe rules for a figure\n\nEach figure was built in up to three \"developments\". The first decided, \"on the basis of frequency considerations\", whether the figure would be closed, open, or left uncommitted for the moment. One rule Cohen printed:\n\nIf (this is a first development\nand the last figure was open\nand at least n figures have been done\nand at least q of them were open\nand at least t units of space are now available)\nThen\nThis figure will be closed\n\nAfter a closed first development, a second could divide the figure, shade it, add a closed form to it, or draw a closed or an open form inside it. If the second development was a series of parallel lines inside, a third could add another series \"perpendicular to first\" or \"alongside the first\". Words such as \"boulder\" and \"penumbra\" in his rules were Cohen's own descriptions; the program did not attach such descriptions to the things it drew.\n\nThe shapes themselves came from repetition protocols. One \"requires the line to move a given distance (more-or-less) and then change direction, continuing this cycle a given number of times\"; closed forms were made by a similar \"go, turn, repeat\" cycle. Over all of this, avoidance protocols prohibited the program \"from ignoring the existence of one figure in drawing another one\".\n\nChance inside limits\n\nCohen defined randomness as \"the impossibility of predicting the outcome of a choice on the basis of previously-made choices\". His rules took the form if (a and b and … n) then p% of the time do x, q% of the time do y. For the proportions of a closed loop, for example: 50 per cent of the time between 1:4 and 1:6, 12 per cent between 3:4 and 7:8.\n\nThe program kept track of the drawing in a coarse matrix of 90 by 160 cells, recording which figure occupied each cell. Before starting, it \"roughens\" the surface, declaring some parts unusable for new figures, \"in order to maximize the rate of change of density across the image\".\n\nNew drawing\nReconstruction by JAEV after Cohen's description of AARON in 1979: a roughened 32 × 20 matrix, the first-development rule above, closed and open forms, second and third developments, and lines that veer towards points rather than reaching them. The two proportion frequencies are Cohen's; all other numbers are invented, and avoidance is done crudely by reserving rectangles. Not Cohen's program or a drawing by AARON. Code CC BY 4.0.\n\nCohen tested the program in public. At documenta 6 in Kassel and at the Stedelijk Museum in Amsterdam it drew continuously, on a display terminal and with a small drawing robot on the floor. Its later machines are described in Plotter art. The rules compare with the one-sentence instructions of Sol LeWitt: LeWitt's were written for a person, Cohen's for a program that decides each step from what is already on the paper."},
{"type": "note", "title": "Air-quality measurements as material", "url": "https://jaev.gallery/notes/air-quality-data-as-art-material/",
   "description": "What European air-quality stations measure, what nitrogen dioxide and ozone are, the limits, and what to know before using unverified data in a work.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "air pollution", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q131123"}], "mentions": [{"name": "nitrogen dioxide", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q207895"}, {"name": "ozone", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q36933"}, {"name": "European Environment Agency", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q632988"}],
   "sources": [{"title": "Up-to-date air quality data viewer. European Environment Agency", "url": "https://discomap.eea.europa.eu/Map/UTDViewer/UTDViewer"}, {"title": "“Unverified Air”, Olof Broström. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/unverified-air/"}, {"title": "“CAMS ground-level NO2 forecast”. European Climate and Health Observatory, European Environment Agency", "url": "https://climate-adapt.eea.europa.eu/en/observatory/publications-data/analysis-data/cams-ground-level-no2-forecast"}, {"title": "“Nitrogen dioxide (NO₂)”, in Air quality status in Europe 2026. European Environment Agency, 30 April 2026", "url": "https://www.eea.europa.eu/en/analysis/publications/air-quality-status-report-2026/nitrogen-dioxide-no2"}, {"title": "“Ozone (O₃)”, in Air quality status in Europe 2026. European Environment Agency, 30 April 2026", "url": "https://www.eea.europa.eu/en/analysis/publications/air-quality-status-report-2026/ozone-o3"}, {"title": "“Ambient (outdoor) air pollution”, fact sheet. World Health Organization", "url": "https://www.who.int/news-room/fact-sheets/detail/ambient-(outdoor)-air-quality-and-health"}],
   "related": {"notes":["bitcoin-difficulty","commons-images-as-material","line-hatching"],"editorial":["generative-art","plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/air-quality-data-as-art-material-olof-brostrom-unverified-air-0011.jpg", "alt": "About forty buildings drawn in thin black lines on cream paper, seen from above at an angle: two long slabs, a tower block and low rows. The open ground between them is filled with dense red lines; the roofs carry fine blue lines.", "credit": "Olof Broström, Unverified Air, no. 11: Schiedam-Alphons Arienstraat, 2026. JAEV."},
   "text": "Across Europe, measuring stations sample the air every hour and report what they find to the European Environment Agency (EEA), which publishes the newest readings within a few hours. For an artist these numbers are a material like any other: they arrive every day, they belong to a real place, and they describe something nobody can see.\n\nWhat is measured\n\nEach reading is a concentration at one station, usually given in micrograms per cubic metre (µg/m³) and averaged over an hour. Two gases matter most for the works discussed here.\n\nNitrogen dioxide (NO₂) comes from burning. According to the EEA, transport is the main source and emits half of Europe's nitrogen oxides; road traffic releases them close to the ground in densely populated areas.\n\nOzone (O₃) at ground level is not released directly by any source. It forms when heat and sunlight drive reactions between nitrogen oxides and volatile organic compounds.\n\nLimits and how often they are passed\n\nUnder the EU directives, the hourly NO₂ concentration should not exceed 200 µg/m³ more than 18 times a year, and the annual mean should not exceed 40 µg/m³. The WHO's 2021 guidelines are stricter for the long term: an annual mean of 10 µg/m³ and a daily value of 25 µg/m³ on no more than three or four days a year.\n\nThe gap shows in the EEA's figures for 2025: 0.5 % of stations were above the EU annual limit for NO₂, 87 % of them traffic stations, while 66.9 % were above the WHO annual guideline. For ozone, 22.4 % of stations were above the EU target value.\n\nUnverified data\n\nThe newest readings come out two to five hours after measurement and cover the last ten days. The countries have not validated or verified them, the EEA states, and they should not be used to check compliance with air-quality standards. That is a limitation for a report. The same limitation, for a drawing, can be the subject: the reading as it stood on the day.\n\nTwo more things follow from the data. A station measures the air where it stands, not a street or a city. The hours also do not line up: nitrogen dioxide peaks near busy streets in the morning and evening rush, while ozone rises in the afternoon, so a day's highest hour of each comes from different times.\n\nWhere to see it\n\nOlof Broström's Unverified Air makes one drawing a day for a year, from 4 October 2026 to 3 October 2027. Each day the program draws a country at random, then a station there that measures both gases, and lays the previous day's highest hour of each over the buildings around it: nitrogen dioxide as red lines on the open ground, ozone as blue lines over the roofs, closer together as the values rise. The air-quality figures are the EEA's unverified up-to-date data, published under CC BY 4.0."},
{"type": "note", "title": "Astrid Sampe, Sten Kallin and the computer textile", "url": "https://jaev.gallery/notes/astrid-sampe-computer-textile/",
   "description": "How the designer Astrid Sampe and IBM programmer Sten Kallin made printed fabrics from plotter drawings on an IBM 1130, and which of them museums hold.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Astrid Sampe", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q430667"}], "mentions": [{"name": "Sten Kallin", "type": "Person", "sameAs": null}, {"name": "IBM 1130", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q3146513"}, {"name": "Art Institute of Chicago", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q239303"}, {"name": "Nationalmuseum", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q842858"}, {"name": "Ljungbergs Textiltryck", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q133415602"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}],
   "sources": [{"title": "Marika Bogren, “Anna Astrid Sampe”. Svenskt kvinnobiografiskt lexikon, 2021 (translated by Alexia Grosjean)", "url": "https://www.skbl.se/en/article/AnnaAstridSampe"}, {"title": "Sten Kallin, interviewed by Anna Orrghen, 10 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "Gardintyg “Dataros” (NMK 57/1981). Nationalmuseum, Stockholm", "url": "https://collection.nationalmuseum.se/sv/collection/item/3915"}, {"title": "Astrid Sampe with computer programmer Sten Kallin and IBM Plotter 1627, Computer Colonne, 1975 (reproduced 1985). The Art Institute of Chicago, 1986.392, gift of Astrid Sampe", "url": "https://www.artic.edu/artworks/107812/computer-colonne"}],
   "related": {"notes":["ibm-1130-swedish-computer-art","calcomp-565","sture-johannesson","line-hatching"],"editorial":["computer-art-in-sweden","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/astrid-sampe-portrait-konstnarslexikon.jpg", "alt": "Black-and-white halftone portrait of Astrid Sampe, a woman with dark hair swept up, looking down at a dark patterned fabric she holds in her hands.", "credit": "Astrid Sampe, portrait reproduced in Allhems Svenskt konstnärslexikon. Photographer unknown; public domain, via Wikimedia Commons."},
   "text": "From the late 1960s to the mid-1970s the Swedish textile designer Astrid Sampe (1909–2002) made printed fabrics from drawings by a computer. Sten Kallin, an engineer at IBM in Sweden, wrote the programs, and a pen plotter attached to an IBM 1130 made the drawings. They are among the first computer-made textile patterns in Sweden.\n\nThe call\n\nSampe had been head of the Textilkammare, the textile studio of the Stockholm department store Nordiska Kompaniet (NK), from 1937. In Kallin's account, she rang IBM and asked for its design department. There was none, so the switchboard passed her to Kallin, who taught programming and was known for odd ideas: \"can you talk to this lady, she wants to draw something strange on computers\".\n\nThe machine\n\nKallin's IBM 1130 stood in a small room at IBM's training department in Solna, driving printers by day; evenings and weekends it was his. With it came a drum plotter no one else wanted: the paper is wrapped round a drum that turns back and forth while the pen moves sideways, in steps of, as Kallin remembers it, about a millimetre. The pen could move in only eight directions: one step sideways, one step of the drum, or both at once.\n\nThe cross\n\nSampe had been asked for a picture for a Red Cross charity auction and wanted to draw the red cross with a computer. Kallin wrote a program that drew the cross again and again, each time smaller and turned. A menu let her set how many crosses, how many degrees each one turned and how many per cent it shrank. They sat at the machine one evening as she tried values.\n\nThe pen sat a little loose, so a slanting line, made of small steps, came out uneven: \"It is somehow a little human, or it has a little character or a little chance in the line.\" Where many such lines lay close together at slightly different angles, they made moiré.\n\nNew drawing\nReconstruction by JAEV after Kallin's account of the cross program: a cross drawn again and again, smaller and turned each time, by a pen that moves in whole steps in eight directions and sits a little loose. Each new drawing picks new values for the three settings Sampe could change. The step size, the looseness and the cross's proportions are JAEV's choices; Sampe's values, and the original sheets, are not known to us. Code CC BY 4.0.\n\nFrom plotter to fabric\n\nA few months later a parcel came to Kallin's home: ten metres of curtain fabric with \"this computer rose\" on it, enlarged and printed red on white glass-fibre cloth, with a shorter piece in brown on coarse linen, from Almedahls. Nationalmuseum holds a curtain fabric by Sampe called Dataros (computer rose), glass fibre printed in brown, made in 1967 at Ljungbergs Textiltryck. The name and the cloth match Kallin's account; the colour and the maker do not.\n\nSampe came back twice. For a commission to design the binder of the Swedish postcode directory, Kallin used almost the same program to draw a post horn. The second time he offered his experiments with curves: \"really just a heavily disturbed sine curve that is repeated\", mirrored around a centre line, with proportions shrinking towards the edges so that the pattern looks three-dimensional.\n\nThe Art Institute of Chicago holds Computer Colonne, dated 1975, a screen-printed cotton given by Sampe in 1986. Its record credits \"Astrid Sampe with computer programmer Sten Kallin and IBM Plotter 1627\"; the example is a reproduction from 1985. In a printed picture Kallin showed in the interview, a design is captioned \"Computer Column, one of Astrid Sampe's and IBM's computer patterns\", without his name. He was not paid, except with lengths of fabric.\n\nThe sources date the work differently: 1967 for Dataros, \"around 1970\" in Sampe's biography, 1975 for Computer Colonne. Kallin also wrote programs of the same kind for Sture Johannesson. The wider story is in Computer Art in Sweden."},
{"type": "note", "title": "AxiDraw (Evil Mad Scientist, 2016)", "url": "https://jaev.gallery/notes/axidraw/",
   "description": "The AxiDraw, the pen plotter Evil Mad Scientist made from 2016: travel, resolution, how Inkscape and the command line drive it, and the NextDraw after it.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-22",
   "author": "JAEV Editorial",
   "about": [{"name": "AxiDraw", "type": "Thing", "sameAs": null}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Evil Mad Scientist", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q109968929"}, {"name": "Windell Oskay", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q135504010"}, {"name": "Lenore Edman", "type": "Person", "sameAs": null}, {"name": "Lindsay Wilson", "type": "Person", "sameAs": null}, {"name": "Bantam Tools", "type": "Organization", "sameAs": null}, {"name": "Inkscape", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q8041"}, {"name": "Matt DesLauriers", "type": "Person", "sameAs": null}, {"name": "Licia He", "type": "Person", "sameAs": null}],
   "sources": [{"title": "“A Look Back: The AxiDraw Story (Part 1)”. Bantam Tools blog, interview with Lindsay Wilson", "url": "https://content.bantamtools.com/blog/alookback"}, {"title": "Windell Oskay, “The AxiDraw Drawing Machine”. Evil Mad Scientist, 9 March 2016", "url": "https://www.evilmadscientist.com/2016/axidraw/"}, {"title": "AxiDraw V3. Evil Mad Scientist shop", "url": "https://shop.evilmadscientist.com/productsmenu/846"}, {"title": "Bantam Tools (Zach Hendel), comments on this note, email to JAEV, 22 October 2026", "url": "https://bantamtools.com"}, {"title": "AxiDraw. axidraw.com", "url": "https://axidraw.com/"}, {"title": "“AxiDraw Command Line Interface”. axidraw.com documentation", "url": "https://axidraw.com/doc/cli_api/"}, {"title": "Brian Schmalz, “EiBotBoard”. schmalzhaus.com", "url": "https://www.schmalzhaus.com/EBB/"}, {"title": "Matt DesLauriers, “Pen Plotter Art & Algorithms, Part 1”, 30 December 2017", "url": "https://mattdesl.svbtle.com/pen-plotter-1"}, {"title": "Licia He, Even when I want to., 2022. Gazelli Art House", "url": "https://art.gazelliarthouse.com/products/even-when-i-want-to"}, {"title": "“Evil Mad Scientist joins Bantam Tools”. Evil Mad Scientist, 16 January 2024", "url": "https://www.evilmadscientist.com/2024/bantam-tools/"}, {"title": "“Introducing Bantam Tools NextDraw”. Evil Mad Scientist, 29 April 2024", "url": "https://www.evilmadscientist.com/2024/bantam-tools-nextdraw/"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["plotter-pens","vpype","plotter-path-optimisation","hp-7475a","hp-gl"],"editorial":["plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/axidraw-jaev.jpg", "alt": "Left: a grey rectangle labelled usable travel 300 × 218 mm, with a black spiral drawn inside it as a chain of short straight lines. A small red square marks part of the spiral. Right: that part enlarged in a red frame, the lines clearly straight between red dots, labelled each move: a straight line. Below it a ruler with 80 fine ticks, labelled 1 mm = 80 motor steps.", "credit": "Diagram by JAEV: the AxiDraw V3's usable travel, 300 × 218 mm, with a spiral drawn as short straight moves (enlarged on the right, red dots where one move ends), and one millimetre divided into the machine's 80 steps. CC BY 4.0."},
   "text": "The AxiDraw is a pen plotter that Evil Mad Scientist Laboratories made in Sunnyvale, California. The first AxiDraw was built in 2014 by Lindsay Wilson, of laser-cut plywood; in 2016 he contacted Evil Mad Scientist, who adapted his design. The company announced its version on 9 March 2016 as \"a simple, modern, precise, and versatile pen plotter\" that draws with \"fountain pens, permanent markers, and other writing implements\". It holds an ordinary pen in an arm above a sheet lying on the table.\n\nThe machine\n\nTwo stepper motors on the base move the pen in the two directions; the paper is put in by hand. The arm cannot press down hard, so the AxiDraw draws but does not cut. For the AxiDraw V3, Evil Mad Scientist gives these figures:\n\nusable pen travel 300 × 218 mm, just over A4\n\n2,032 steps per inch, or 80 steps per millimetre\n\nrepeatability typically better than 0.1 mm at low speeds; the 80 steps per millimetre describe how finely the motion is divided, not how accurately the pen returns to a point\n\ntop speed 38 cm a second\n\npens up to 16 mm across; the machine weighs 2.2 kg\n\nThe AxiDraw V3 itself was introduced in November 2016. Larger models followed: the V3/A3 and SE/A3 for A3 paper and the SE/A1 with a travel of 864 × 594 mm. The AxiDraw needs no special pens or ink. The note on plotter pens says which work.\n\nHow it is told what to draw\n\nThe AxiDraw is normally run from Inkscape, the free vector drawing program, through a set of extensions; the driver software is open source. It plots SVG files. The same software runs from the command line, as axicli file.svg, and from Python. The program can also reorder the lines before plotting. Why the order matters is explained in the note on plotter path optimisation; vpype is another tool for preparing the file.\n\nUnderneath, the AxiDraw can be programmed directly in the command protocol of the EiBotBoard (EBB). Its SM command makes the motors go \"in a straight line between two points\", and it \"does not understand G-code\". The AxiDraw software turns circles and rectangles into paths, and a curve therefore reaches the motors as many short straight moves, as in the diagram above.\n\nArtists\n\nMatt DesLauriers bought an AxiDraw V3 in March 2017 and wrote about plotting generative art with it in December that year. Licia He paints with an AxiDraw: Even when I want to. (2022) was \"physically rendered\" by \"Pen plotters (Axidraw A3/V3)\" with watermedia, from a program written in Python. More are in JAEV's text on plotter art.\n\nAfter 2024\n\nIn January 2024 Bantam Tools, a maker of desktop CNC machines, bought Evil Mad Scientist, and its founders Windell Oskay and Lenore Edman moved to Bantam's headquarters in Peekskill, New York. In April Bantam Tools brought out the NextDraw, in three models from A4 to A1. The company describes it as the next generation of the AxiDraw line, developed with Windell Oskay as its CTO. The AxiDraw V3 is no longer in production; its development continues at Bantam Tools in Peekskill, and the current software still drives the older AxiDraw models.\n\nOlof Broström's Unverified Air at JAEV is stored as files for a pen plotter, in black, red and blue ink.\n\nUpdated on 22 October 2026 with information from Bantam Tools: the AxiDraw's origin, the difference between resolution and repeatability, and the NextDraw."},
{"type": "note", "title": "Beck & Jung (Holger Bäckström and Bo Ljungberg)", "url": "https://jaev.gallery/notes/beck-and-jung/",
   "description": "Beck & Jung were the Lund artist Holger Bäckström and the engineer Bo Ljungberg. Their image alphabet, line printers and the Chromo Cube.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Beck & Jung", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q10427586"}], "mentions": [{"name": "Holger Bäckström", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5591690"}, {"name": "Bo Ljungberg", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19352454"}, {"name": "Mikael Jern", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63869789"}, {"name": "Sture Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5884840"}, {"name": "Lund University", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q218506"}],
   "sources": [{"title": "“Bäckström, Holger (1939–1997), bildkonstnär, skulptör, grafiker, datakonstnär”. Kulturportal Lund", "url": "https://kulturportallund.se/lundaprofil_11759/"}, {"title": "Elisabeth Fagerstedt, “Beck & Jung: datakonstens pionjärer”, Uppsala konstmuseum 2009, published on Elisabeth Fagerstedt konsttexter, 2012", "url": "http://elisabethfagerstedtkonsttext.blogspot.com/2012/05/beck-jung-holger-backstrom-1939-1997.html"}, {"title": "“Beck & Ljung”. Stockholms läns museum", "url": "https://stockholmslansmuseum.se/konstnar/beck-ljung/"}, {"title": "Lars-Gunnar Bodin, interviewed by Anna Orrghen, 5 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/26-lars-gunnar-bodin.pdf"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}, {"title": "Lisa Adang, “The Aesthetics of the Color Plotter”. Cooper Hewitt, Smithsonian Design Museum, 8 May 2018", "url": "https://www.cooperhewitt.org/2018/05/08/aethetics-of-the-color-plotter/"}, {"title": "“Beck och Jung”. Region Blekinge, Konst i Blekinge", "url": "https://regionblekinge.se/konst-i-blekinge/konstsamling/film---guldkorn-i-konstsamlingen/beck-och-jung.html"}, {"title": "Sture Johannesson and Ann-Charlotte Johannesson, interviewed by Anna Orrghen, 2 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/4-ann-charlotte-och-sture-johannesson.pdf"}, {"title": "Artiste et ordinateur: [exposition], Paris, Lille, Caen, 1979. Centre culturel suédois, Paris. Catalogue record, LIBRIS", "url": "https://libris.kb.se/2kc0n4nd5g0hkvz"}],
   "related": {"notes":["hertz-ink-jet-colour-plotter","color-program-mikael-jern","ibm-1130-swedish-computer-art"],"editorial":["the-colour-cubes","computer-art-in-sweden"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/beck-and-jung-jaev.jpg", "alt": "Six geometric forms on continuous printer paper with sprocket holes along the edges, each made of one repeated letter: a circle of Os, an ellipse of Xs, a square of Hs, a rhombus of Ms painted red underneath, a triangle of Ws and a half circle of 8s.", "credit": "Reconstruction by JAEV after descriptions of Beck & Jung's image alphabet as printed on a line printer, not an original work by Beck & Jung. CC BY 4.0."},
   "text": "Beck & Jung was the shared name of the Lund artist Holger Bäckström (1939–1997) and the engineer Bo Ljungberg (1939–2007), who worked together from the mid-1960s and began, very early, to use computers in their art. They are best known for the Chromo Cube prints, made on the ink-jet colour plotter at Lund University.\n\nTwo people, one name\n\nThe two were childhood friends. Bäckström studied at Konstfack in Stockholm from 1960 to 1964; Ljungberg studied building engineering and mathematics. Kulturportal Lund dates their partnership from 1965 and calls Beck & Jung their \"artist and company name\". The curator Elisabeth Fagerstedt describes the name as working like a brand, after the collective methods of advertising agencies and architects' offices, so that the individual artist stepped back. Stockholms läns museum says they began to use computers in 1966.\n\nThe image alphabet\n\nTheir first system was an image alphabet: a small set of geometric forms such as circles, ellipses, squares and rhombuses that could be turned and combined into new pictures, most of them figurative, like a dog with a ball or a house. Stockholms läns museum says six basic forms and a first joint exhibition at Lunds konsthall in 1967; Fagerstedt counts eleven forms.\n\nThe combinations were worked out by computer, with IBM in Malmö, and printed on a simple line printer. A line printer can only print characters, so their forms were filled in with letters, as the composer Lars-Gunnar Bodin recalled; the artists then chose sections, painted them and joined them together.\n\nThe same alphabet ran through their objects. Felixsnurran (1968) is 35 plates printed on both sides, which Fagerstedt gives as 34,359,738,368 possible variations. Hej patient (1973), at Huddinge hospital, is the alphabet in lacquered aluminium, 4 × 12 metres.\n\nColour from Lund\n\nThe cubes came from the programmer Mikael Jern, whose software COLOR drew a cube of 17 × 17 × 17 coloured cubes on the Hertz plotter. Jern says Beck & Jung had read about his cubes and asked to use the programs; he made the first ones for them, and the programmer Bob Wissler then ran the programs for them. Their cubes, he says, hung in SAS aircraft and at IKEA.\n\nThe sources give different dates. Fagerstedt says they made colour pictures on the new Lund plotter from 1972, first shown at Arkivmuseet in Lund in 1973, and began the Chromocubes in 1980, showing them at Pratt Institute in New York in 1981. Cooper Hewitt, which holds The Chromo Cube (1980), a gift of the artists, dates their contact with Jern to 1980. Region Blekinge holds Chromo Cube and Bildalfabetet.\n\nWho made the cubes is disputed. Jern claims the image but calls the collaboration \"very good\" and says only they could take it out as art. Sture Johannesson said they \"just took the printouts\" of Jern's logo. The case is set out in full in The colour cubes; Olof Broström's Automatic Colour Cubes at JAEV returns to the same cube.\n\nIn 1979 Beck & Jung were in L'Artiste et l'Ordinateur at the Centre culturel suédois in Paris, whose catalogue names them; the exhibition is described in Computer Art in Sweden."},
{"type": "note", "title": "The Benson plotter (Paris, 1970–1983)", "url": "https://jaev.gallery/notes/benson-plotter/",
   "description": "The French Benson flatbed plotter Manfred Mohr drew on in Paris from 1970 to 1983: its size, step and paper, and how a drawing reached it.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}, {"name": "Vera Molnár", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1658002"}, {"name": "CDC 6400", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q976542"}],
   "sources": [{"title": "HP 7580A Drafting Plotter. HP Computer Museum", "url": "https://www.hpmuseum.net/display_item.php?hw=76"}, {"title": "Manfred Mohr, “Working at Météorologie Nationale, Paris in 1970”", "url": "https://emohr.com/paris-1971/meteo.html"}, {"title": "Manfred Mohr, “50 Year Celebration: Time Line”", "url": "https://emohr.com/ManfredMohr_50YearCelebration_TimeLine.html"}, {"title": "Manfred Mohr, “Computer Graphics – Une Esthétique Programmée”, ARC, Musée d'Art Moderne de la Ville de Paris, 1971", "url": "https://www.emohr.com/paris-1971/p1.html"}, {"title": "Vera Molnár, (Des)ordres, 1974. Phillips, Ex-Machina: A History of Generative Art, London, July 2022, lot 22", "url": "https://phillips.com/detail/vera-molnar/UK090322/22"}],
   "related": {"notes":["zuse-graphomat-z64","calcomp-565","hp-gl","vera-molnar-interruptions"],"editorial":["manfred-mohr","plotter-art","vera-molnar"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/benson-plotter-jaev.jpg", "alt": "A simple line drawing of a flatbed plotter seen from above: a rectangular bed with a sheet of paper, a bridge across it on two rails, and a pen carriage on the bridge. To the left of the bridge the paper is covered with closely spaced parallel lines; a red line runs from the top of the next row down to the pen. Red arrows show the bridge moving along the bed and the pen moving along the bridge.", "credit": "Diagram by JAEV: a flatbed plotter seen from above. The paper lies still; the bridge moves along the bed and the pen along the bridge (red arrows). A general drawing, not the Benson 1284 itself. CC BY 4.0."},
   "text": "Benson was a French maker of pen plotters. In the late 1970s, according to the HP Computer Museum, CalComp and Xynetics dominated the American market while \"a French company, Benson, held sway in Europe\". In art history the name belongs to one machine: the Benson 1284 flatbed plotter at the French weather service in Paris, on which Manfred Mohr made his drawings from 1970 to 1983.\n\nNearly everything known about that machine comes from Mohr's own pages.\n\nHow Mohr got there\n\nMohr, an artist living in Paris, wrote his first computer program in October 1969. He had seen the weather service's plotter in a TV news report and asked to use it together with its CDC 6400 computer. On 17 June 1970 he received written permission to work in the computing centre at nights and weekends. He worked there until 1983, when he moved to New York. In his words he was there \"almost nightly\". His first pen-plotter drawings had been made a few months earlier on a Zuse plotter in Darmstadt.\n\nThe machine\n\nA flatbed plotter holds the paper still while the pen moves over it in both directions. Mohr describes the Benson as follows:\n\nSize: a drawing area of roughly 1 × 1.30 metres, large for the time.\n\nStep: 0.1 mm, or 0.2 mm in a fast mode, so the lines came out smooth.\n\nPaper: held down by static electricity. He drew on drawing paper, tracing paper, thin canvas and a treated metal plate.\n\nFrom program to drawing\n\nMohr wrote his programs in Fortran IV. His photographs from the weather service show the steps: punching the program on cards and feeding them in, running it from the console of the CDC 6400, preparing magnetic tape and mounting it on a tape drive, setting up the tape to transfer the data to the plotter, watching the plotter work and changing its pens. The first program he plotted there was P-21, the band-structures.\n\nThe plotter in the museum\n\nFor Mohr's exhibition Computer Graphics – Une Esthétique Programmée at ARC, Musée d'Art Moderne de la Ville de Paris, which opened on 11 May 1971, Benson-France installed a plotter of the same type in the gallery, with a magnetic tape drive. At the opening and every afternoon during the show, Mohr demonstrated how the machine drew his work.\n\nBenson paper\n\nBenson's name also appears on Vera Molnár's (Des)ordres (1974): nine drawings on one strip of \"Benson plotter paper\", 4.96 metres long and 35.9 cm wide, sold at Phillips in London in 2022. The catalogue does not say which machine drew it.\n\nHow the Benson compares with other machines of its time is set out in JAEV's text on plotter art and in the notes on the CalComp 565 and HP-GL."},
{"type": "note", "title": "Bézier curves", "url": "https://jaev.gallery/notes/bezier-curves/",
   "description": "How four points define a Bézier curve, how de Casteljau's construction draws it, why Renault and Citroën needed it, and how a plotter draws one.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Bézier curve", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q214728"}, {"name": "De Casteljau's algorithm", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1179419"}], "mentions": [{"name": "Pierre Bézier", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q372584"}, {"name": "Paul de Casteljau", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1396450"}, {"name": "Renault", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q6686"}, {"name": "Citroën", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q6746"}, {"name": "UNISURF", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q3550682"}, {"name": "PostScript", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q218170"}],
   "sources": [{"title": "“Bézier curve”. Wikipedia", "url": "https://en.wikipedia.org/wiki/B%C3%A9zier_curve"}, {"title": "Pomax, “A Primer on Bézier Curves”", "url": "https://pomax.github.io/bezierinfo/"}, {"title": "“Pierre Bézier”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Pierre_B%C3%A9zier"}, {"title": "“Bézier and de Casteljau: two engineers, one beautiful curve”. FontLab blog, 1 July 2025", "url": "https://blog.fontlab.com/2025/07/01/bezier-vs-de-casteljau/"}, {"title": "“French Curves and Bézier Splines”. ThatsMaths, 6 February 2014", "url": "https://thatsmaths.com/2014/02/06/french-curves-and-bezier-splines/"}, {"title": "“Paths”. Scalable Vector Graphics (SVG) 2, W3C", "url": "https://www.w3.org/TR/SVG2/paths.html"}, {"title": "Brian Schmalz, “EiBotBoard” (the controller of the EggBot and AxiDraw)", "url": "https://www.schmalzhaus.com/EBB/"}, {"title": "“Command reference”. vpype documentation", "url": "https://vpype.readthedocs.io/en/latest/reference.html"}, {"title": "Olof Broström, Difficulty no. 972396, 21 October 2026. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/difficulty/972396/"}],
   "related": {"notes":["hp-gl","plotter-path-optimisation","line-hatching","flow-fields"],"editorial":["plotter-art","generative-art"],"exhibitions":["difficulty"]},
   "image": {"url": "https://jaev.gallery/assets/notes/bezier-curves-jaev.jpg", "alt": "A red arch drawn on warm paper between two low end points. Grey lines join four small circles, the control points, two of them high above the arch. Dozens of thin black straight lines fan out between the grey sides, each touching the red curve at one point, so that together they outline it.", "credit": "Diagram by JAEV: one cubic Bézier curve (red), its four control points and control polygon (grey), and for 49 values of t the last line of de Casteljau's construction (black), which touches the curve at the point it constructs. CC BY 4.0."},
   "text": "A Bézier curve is a smooth curve defined by a few points: it starts at the first, ends at the last, and is pulled towards the ones in between without passing through them. It is named after the engineer Pierre Bézier (1910–1999), who used it in the 1960s to design the bodywork of Renault cars. Today it describes the paths in drawing programs, the outlines of letters in fonts and the curves in SVG files.\n\nTwo car makers\n\nBézier worked for Renault from 1933 to 1975, and his system for designing car bodies by computer, UNISURF, came into use in 1968. He made the curves known around 1962 and patented their use in computer-aided design, but he did not invent them. At the end of the 1950s Paul de Casteljau, at Citroën, had worked out the same curves and a way to compute them. Citroën asked him not to publish, and he could only write it up in 1985. So the curve carries Bézier's name, and the method of drawing it carries de Casteljau's.\n\nHow it works\n\nThe most common kind is cubic and has four points, P0 and P3 at the ends and P1 and P2 as control points. The curve leaves its start in the direction of the line from P0 to P1 and arrives at its end along the line from P2 to P3.\n\nDe Casteljau's construction finds any point on the curve with nothing but division of lines. Choose a number t between 0 and 1, say 0.3.\n\nDivide each of the three lines P0–P1, P1–P2 and P2–P3 at 30 per cent of its length. That gives three new points.\n\nJoin them with two lines and divide those at 30 per cent too, which gives two points.\n\nJoin those two and divide the last line at 30 per cent. That point is on the curve.\n\nRepeat for every t from 0 to 1 and the points trace the whole curve. The last line in step 3 touches the curve at the point it finds, which is what the picture at the top shows: 49 such lines, and the curve they outline in red.\n\nNew drawing\nSketch by JAEV: a cubic Bézier curve with four random points. Thin lines: the last step of de Casteljau's construction for 41 values of t, each touching the curve once. Dashed and solid lines and the black dot: the whole construction for one value of t. Code CC BY 4.0.\n\nIn files and fonts\n\nThe SVG format has a command for each kind: C draws a cubic curve \"using (x1,y1) as the control point at the beginning of the curve\" and a second one at the end, and Q a quadratic curve with a single control point. PostScript and SVG build their curved shapes from cubic curves; TrueType fonts use quadratic ones.\n\nOn a plotter\n\nA pen plotter cannot draw a curve as such. The controller of the AxiDraw, for example, moves its motors \"in a straight line between two points\". So the curve is \"flattened\": points are computed along it and joined with short straight lines. The plotter program vpype does this when it reads an SVG file: every curve is \"linearized and approximated by polylines\", by default with segments no longer than 0.1 mm. How those many short lines are then put in order is described in plotter path optimisation; the language older plotters were sent is in HP-GL, and more on drawing machines in Plotter Art.\n\nOlof Broström's Difficulty at JAEV, one drawing a day made automatically from the day's aurora forecast and the day's first block, is built of such curves: sheet no. 972396, of 21 October 2026, has 5,672 Bézier curves, 26.6 m of line if plotted at print size."},
{"type": "note", "title": "Bitcoin's difficulty", "url": "https://jaev.gallery/notes/bitcoin-difficulty/",
   "description": "What Bitcoin's difficulty measures, how the target, hash and nonce work, and why the network adjusts it every 2,016 blocks to keep ten minutes per block.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "proof of work", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q7249984"}, {"name": "Bitcoin", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q131723"}], "mentions": [{"name": "SHA-256", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q110651361"}],
   "sources": [{"title": "“Difficulty”. Bitcoin Wiki", "url": "https://en.bitcoin.it/wiki/Difficulty"}, {"title": "“Block Chain”, Bitcoin Developer Reference. developer.bitcoin.org", "url": "https://developer.bitcoin.org/reference/block_chain.html"}, {"title": "“Block Chain”, Bitcoin Developer Guide. developer.bitcoin.org", "url": "https://developer.bitcoin.org/devguide/block_chain.html"}, {"title": "“Difficulty”, Olof Broström. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/difficulty/"}, {"title": "Block 972,231. mempool.space, retrieved 20 October 2026", "url": "https://mempool.space/block/00000000000000000001051481af692a7a4be8604f0c36e8da874a4207d0c0ba"}, {"title": "Difficulty adjustments, last month. mempool.space API, retrieved 20 October 2026", "url": "https://mempool.space/api/v1/mining/difficulty-adjustments/1m"}],
   "related": {"notes":["sha-256-as-random-source","air-quality-data-as-art-material"],"editorial":["generative-art"],"exhibitions":["difficulty"]},
   "image": {"url": "https://jaev.gallery/assets/notes/bitcoin-difficulty-olof-brostrom-difficulty-972231.jpg", "alt": "Hundreds of thin black horizontal lines over a background that shifts from salmon pink at the top to pale yellow at the bottom. In the upper half the lines are lifted into a deep fold and a ridge, like a landscape seen from the side; lower down they lie almost flat.", "credit": "Olof Broström, Difficulty no. 972231, 2026. JAEV."},
   "text": "Bitcoin's difficulty is a number that says how hard it is to add the next block to the Bitcoin ledger. It compares the current target with a fixed reference target, and it is recalculated every 2,016 blocks so that a new block is found about every ten minutes.\n\nTarget, hash and nonce\n\nA block is a batch of transactions with an 80-byte header. The header holds a reference to the previous block, a summary of the transactions, a time, the current target in compressed form, and a 4-byte field called the nonce. The header is hashed twice with SHA-256 (see the note on SHA-256). Read as a 256-bit number, the result must be less than or equal to the target.\n\nThere is no way to calculate a header that meets the target. The only way is to guess: change the nonce, which is there to be changed, hash again, and repeat until a result happens to be small enough. A small number written out in 64 hexadecimal digits begins with many zeros, which is why the rule can also be put as a hash that \"starts with a required run of zeros\". The block at height 972,231, found on 20 October 2026, has a hash that begins with 19 zeros.\n\nWhat the number means\n\nThe Bitcoin Wiki defines the difficulty as difficulty_1_target / current_target: how many times smaller the target is now than at difficulty 1. The same page gives the expected number of hashes needed for one block as D × 2⁴⁸ / 0xffff, where D is the difficulty, which is close to D × 2³². On 16 October 2026, at block 971,712, the difficulty was set to about 140.6 trillion. By the formula, that is about 6 × 10²³ guesses, on average, for every block.\n\nThe adjustment\n\nEvery 2,016 blocks, the network uses the timestamps in the block headers to see how long the last period took. The ideal is 1,209,600 seconds, two weeks, which is ten minutes per block. If the blocks came faster, the difficulty goes up in proportion, by at most 300 %; if they came slower, it goes down, by at most 75 %. The adjustment of 16 October 2026 raised the difficulty by about 5.9 %.\n\nThe difficulty therefore follows the computing power spent on the whole network, not anything inside a single block. Every block within the same period of 2,016 blocks has the same difficulty.\n\nWhere to see it\n\nOlof Broström's Difficulty is drawn from these blocks. Each day at 00:30 UTC, JAEV's server makes one drawing from the day's aurora forecast and the first block after midnight UTC: the block's hash sets the background colours and the angle of the lines, the number of transactions sets the number of lines, from 100 to 260, the nonce sets how high they are lifted, and the block's height becomes the sheet number. The drawing for 20 October 2026 is Difficulty no. 972231."},
{"type": "note", "title": "Boids (Craig Reynolds, 1986)", "url": "https://jaev.gallery/notes/boids-craig-reynolds/",
   "description": "Boids is Craig Reynolds's 1986 flocking model: each simulated bird follows three local rules, and a flock appears. The rules, the paper and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Boids", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q833640"}], "mentions": [{"name": "Craig Reynolds", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92658"}, {"name": "Daniel Shiffman", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q21521406"}],
   "sources": [{"title": "Craig Reynolds, “Boids: Background and Update”. red3d.com", "url": "https://www.red3d.com/cwr/boids/"}, {"title": "Craig W. Reynolds, “Flocks, Herds, and Schools: A Distributed Behavioral Model”. Computer Graphics 21 (4), SIGGRAPH '87 Conference Proceedings, pp. 25–34", "url": "https://www.cs.toronto.edu/~dt/siggraph97-course/cwr87/"}, {"title": "Daniel Shiffman, The Nature of Code, chapter “Autonomous Agents”", "url": "https://natureofcode.com/autonomous-agents/"}],
   "related": {"notes":["flow-fields","game-of-life","random-walk","processing"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/boids-craig-reynolds-jaev.jpg", "alt": "Thin black lines on warm paper, the paths of about a hundred simulated birds over a short time. They run side by side in several bundles, each bundle turning together; a short red stroke at the end of every path shows where each bird is and which way it flies.", "credit": "Drawing by JAEV: the paths of 130 boids steering by separation, alignment and cohesion, over their last 150 steps; red strokes mark where they end. Our own code after Reynolds's rules. CC BY 4.0."},
   "text": "Boids is a computer model of a flock of birds, made by the computer graphics researcher Craig Reynolds in 1986 and published at the SIGGRAPH conference in 1987 as \"Flocks, Herds, and Schools: A Distributed Behavioral Model\". The program contains no flock, only many simulated birds, each steering by a few rules about its nearest neighbours. The flock is what appears when they all do so at once.\n\nThe three rules\n\nReynolds \"called the generic simulated flocking creatures boids\". A boid sees only the flockmates in its neighbourhood, an area set by a distance from its centre and an angle from its direction of flight; all others are ignored. Inside that area it follows three rules, in Reynolds's words:\n\nSeparation: \"steer to avoid crowding local flockmates\".\n\nAlignment: \"steer towards the average heading of local flockmates\".\n\nCohesion: \"steer to move toward the average position of local flockmates\".\n\nThe 1987 paper gives the same rules as Collision Avoidance, Velocity Matching and Flock Centering, listed \"in order of decreasing precedence\".\n\nNo leader, no plan\n\nThe paper describes the simulated flock as \"an elaboration of a particle system, with the simulated birds being the particles\". Each bird is an independent actor that moves by what it perceives around it, and \"the birds choose their own course\". An animator who wanted the flock to go somewhere could add a shared goal, a direction of migration, but no single bird leads.\n\nNew drawing\nLive sketch by JAEV: 120 boids, each drawn as a short stroke in its direction of flight. A boid looks at others within 50 units, keeps away from those within 16, and turns towards the average heading and position of the rest. They start at random; within seconds they gather into flocks. The field wraps round at the edges. Our own code after Reynolds's rules, not his program. Code CC BY 4.0.\n\nOn screen\n\nThe model was used in the short film Stanley and Stella in: Breaking the Ice, first shown in the Electronic Theater at SIGGRAPH '87. Tim Burton's Batman Returns (1992) used modified boids software from Symbolics for its swarms of bats and flocks of penguins.\n\nIn generative art\n\nDaniel Shiffman's book The Nature of Code builds a flock on the same \"three rules: alignment, cohesion, and separation\", alongside Reynolds's later steering behaviours, among them following a flow field. The model belongs with the other rule systems in these notes where a simple rule, applied by many parts at once, produces a form nobody drew: Conway's Game of Life and diffusion-limited aggregation. See also Generative Art."},
{"type": "note", "title": "Bresenham's line algorithm (1962)", "url": "https://jaev.gallery/notes/bresenham-line-algorithm/",
   "description": "How Jack Bresenham's 1962 rule turns a straight line into steps for a pen plotter, with whole numbers only. The rule, the IBM machines and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Bresenham's line algorithm", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q549860"}], "mentions": [{"name": "Jack Elton Bresenham", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92833"}, {"name": "IBM 1401", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1066933"}, {"name": "IBM 1627", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5968586"}],
   "sources": [{"title": "J. E. Bresenham, “Algorithm for computer control of a digital plotter”. IBM Systems Journal 4:1 (1965), pp. 25–30 (scan)", "url": "https://www.redblobgames.com/grids/line-drawing/mirror/bresenham_line.pdf"}, {"title": "“Bresenham's line algorithm”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm"}, {"title": "“Bresenham line drawing and the IBM 1627”. IBM 1401 restoration project, Computer History Museum", "url": "https://ibm-1401.info/BresenhamLineDraw.html"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["calcomp-565","hp-gl","plotter-path-optimisation","line-hatching"],"editorial":["plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/bresenham-line-algorithm-jaev.jpg", "alt": "Left: a grid of grey dots with a thin dashed red line rising gently across it, and a thick black line that follows it in steps from dot to dot, straight and diagonal. Right: forty such stepped black lines radiating from one point in all directions, like a star.", "credit": "Diagram by JAEV after Bresenham's rule (1965). Left: one line enlarged; red dashes are the wanted line, black is the pen's path from mesh point to mesh point. Right: forty lines from one point, each drawn by the same rule. CC BY 4.0."},
   "text": "Bresenham's line algorithm decides which points of a grid a machine should step through to draw a straight line, using only whole numbers. Jack Bresenham wrote it at IBM in 1962 for a pen plotter and published it in 1965 in the IBM Systems Journal as \"Algorithm for computer control of a digital plotter\". On a screen the grid points are pixels, and the same rule picks which pixels to fill.\n\nThe problem\n\nThe plotter in Bresenham's paper answers each electrical pulse with one of eight moves: one step left, right, up or down, or one step along a diagonal. In his words, \"the plotter can move linearly from a point on a mesh to any adjacent point on the mesh\". A drawing is given as points on that mesh, joined by straight segments.\n\nA segment that is not horizontal, vertical or at 45 degrees can only be drawn as a staircase of these moves, and before every step the computer must choose the next one. Bresenham's rule is to take, each time, \"the mesh point nearest the desired line segment\".\n\nHow it works\n\nTake a line from D1 to D2 that rises less steeply than 45 degrees, the paper's \"first octant\". Let Δa be the number of mesh steps across and Δb the number up. Every move is then either one step across (M1) or one step diagonally across and up (M2). The program keeps a single whole number, the decision value ∇:\n\nStart with ∇ = 2Δb − Δa.\n\nIf ∇ is negative, move one step across and add 2Δb.\n\nOtherwise, move diagonally and add 2Δb − 2Δa.\n\nRepeat until the pen has made Δa moves.\n\nBresenham shows that ∇ always has the same sign as the difference between the distances from the line to the two possible next points, so its sign alone tells which point is nearer. Lines in the other seven directions are handled by swapping the axes or reversing the direction.\n\nInside the loop there is only addition, subtraction and a comparison. The algorithm, the paper says, \"may be programmed without multiplication or division instructions and is efficient with respect to speed of execution and memory utilization\". A 1962 description of the program states that 333 core memory locations were enough.\n\nNew drawing\nLive sketch by JAEV: two random points on a 24 × 14 mesh. The dashed line is the line you want; the thick line is the path the pen takes, from mesh point to mesh point, chosen by the decision value exactly as in Bresenham's paper. Below, the number of straight and diagonal moves. Code CC BY 4.0.\n\nThe machines\n\nIn an account from 2001, Bresenham said he was working in the computation lab at IBM's San Jose development lab, where \"a Calcomp plotter had been attached to an IBM 1401 via the 1407 typewriter console\", and that the algorithm was in production use by the summer of 1962. The volunteers who restore IBM 1401 computers at the Computer History Museum have since gathered 1962 documents. One describes \"an IBM 1401 program (used to control an IBM 1627)\", the name under which IBM sold CalComp's drum plotters; Robert Garner reports that the lab used the 11-inch CalComp 565. The same page lists what is still uncertain, among it whether the program listing that survives is complete.\n\nStill a plotter problem\n\nA pen plotter is still told to draw straight segments between points, in a language such as HP-GL, and the machine has to turn each one into movement. Every drawing in Olof Broström's Unverified Air at JAEV is stored as such a file for a pen plotter, in black, red and blue ink. See also Plotter art and Plotter path optimisation.\n\nAmit Patel of Red Blob Games, whose copy of Bresenham's paper we first used, pointed us in October 2026 to the open-access version from the ACM (source 5)."},
{"type": "note", "title": "CalComp 565 drum plotter", "url": "https://jaev.gallery/notes/calcomp-565/",
   "description": "The CalComp 565, the drum plotter IBM also sold as the 1627: how it moved the pen in steps, the line algorithm written for it, and the artists who used it.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Calcomp plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5018853"}, {"name": "IBM 1627", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5968586"}], "mentions": [{"name": "Jack Elton Bresenham", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92833"}, {"name": "Bresenham's line algorithm", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q549860"}, {"name": "IBM 1401", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1066933"}, {"name": "IBM 1130", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q3146513"}, {"name": "Charles Csuri", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5076580"}, {"name": "Astrid Sampe", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q430667"}, {"name": "Sture Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5884840"}, {"name": "Sten Kallin", "type": "Person", "sameAs": null}],
   "sources": [{"title": "“CalComp Inc.”. Encyclopedia.com (company history)", "url": "https://encyclopedia.com/books/politics-and-business-magazines/calcomp-inc"}, {"title": "“Bresenham line drawing and the IBM 1627”. IBM 1401 restoration project, Computer History Museum", "url": "https://ibm-1401.info/BresenhamLineDraw.html"}, {"title": "Charles Csuri, Sine Curve Man Three, 1967. The Charles A. Csuri Project, Ohio State University", "url": "https://csuriproject.osu.edu/Detail/objects/603"}, {"title": "Astrid Sampe, Computer Colonne, 1975 (reproduced 1985). Art Institute of Chicago", "url": "https://www.artic.edu/artworks/107812/computer-colonne"}, {"title": "“Sture Johannesson: In Memery”. Index – The Swedish Contemporary Art Foundation", "url": "https://indexfoundation.se/exhibitions/sture-johannesson-in-memery"}, {"title": "“1627 Plotter”. IBM 1130 Functional Characteristics, transcribed at ibm1130.net", "url": "http://www.ibm1130.net/functional/Plotter.html"}, {"title": "“Calcomp 565 plotter”. Computer museum, University of Amsterdam", "url": "https://ub.fnwi.uva.nl/computermuseum/calcomp565.html"}, {"title": "“Bresenham's algorithm”. Dictionary of Algorithms and Data Structures, NIST", "url": "https://xlinux.nist.gov/dads/HTML/bresenham.html"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["zuse-graphomat-z64","benson-plotter","hp-gl","astrid-sampe-computer-textile","ibm-1130-swedish-computer-art"],"editorial":["plotter-art","computer-art-in-sweden"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/calcomp-565-marcin-wichary.jpg", "alt": "Close-up of a grey machine with the label CALCOMP 565. Above the label a sheet of graph paper lies over a drum, with two metal rods for the pen carriage; below, the paper roll with a faint plotted line.", "credit": "A CalComp 565 drum plotter. Photo: Marcin Wichary, 2011, CC BY 2.0, via Wikimedia Commons."},
   "text": "The CalComp 565 is a drum plotter made by California Computer Products (CalComp) and sold from the early 1960s. IBM sold the same machine as the IBM 1627 Model 1. Artists in the United States and Sweden drew on it, or on its IBM version, in the 1960s and 1970s.\n\nThe company\n\nTwo engineers, Gene Seid and Robert Morton, built a prototype plotter in Los Angeles from 1953. With three others they incorporated California Computer Products in 1958 and set up in a garage in Downey, California. In the company's account it developed the world's first drum plotter in 1959. By 1961 the 565 was selling well enough for CalComp to go public.\n\nHow it draws\n\nThe paper is a roll with holes along its edges, fed over a drum with pins. When the drum turns, the paper moves up or down under the pen. The pen sits on a carriage that travels left and right across the paper. Every signal from the computer moves the carriage, the paper or both by one step of 1/100 inch (0.254 mm), or raises or lowers the pen. For the 1627 Model 1, IBM gives a drawing width of 11 inches on paper 120 feet long and up to 18,000 steps a minute.\n\nSince paper and pen can move together, there are eight possible moves: along the two axes and along the four diagonals. A line at any other angle has to be drawn as a staircase of these moves, and the computer must decide which move comes next, step by step. The University of Amsterdam's computer museum gives a different step, 0.1 mm at 250 steps a second, for its own 565.\n\nBresenham's line\n\nIn 1962 Jack Bresenham at IBM wrote a program for an IBM 1401 that drove an IBM 1627, choosing the steps for a straight line without any multiplication or division. He published the method in 1965 as \"Algorithm for Computer Control of a Digital Plotter\". It is now known as Bresenham's line algorithm and is used to draw lines with pixels.\n\nArtists on the 565\n\nAt Ohio State University, Charles Csuri drew Sine Curve Man Three (1967) on a CalComp 565, with an IBM 7094 computer and punched cards.\n\nThe Swedish designer Astrid Sampe worked with the IBM programmer Sten Kallin. The Art Institute of Chicago credits her textile Computer Colonne (1975) to Sampe \"with computer programmer Sten Kallin and IBM Plotter 1627\". Kallin also worked with the artist Sture Johannesson from 1970 to 1975. Their works were computed on an IBM 1130 without a screen, fed with punched cards, and drawn on a CalComp drum plotter on a 30 cm paper roll. Both stories are told in Computer art in Sweden and in the notes on Astrid Sampe and the IBM 1130.\n\nWhere to see one\n\nThe University of Amsterdam's computer museum has two 565s. One was used at the university's Van der Waals physics laboratory; the museum restored its wiring and has drawn the Newell Teapot on it.\n\nA pen told where to go one move at a time is still how plotters work: see HP-GL and JAEV's text on plotter art. Olof Broström's Unverified Air at JAEV is stored as files for a pen plotter, one drawing a day."},
{"type": "note", "title": "Catalog (John Whitney, 1961)", "url": "https://jaev.gallery/notes/john-whitney-catalog/",
   "description": "John Whitney's Catalog (1961) is a seven-minute film of effects made on an analogue machine built from a wartime anti-aircraft gun director. How it worked.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "John Whitney", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q3182739"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "IBM", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q37156"}, {"name": "Permutations", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q122661843"}],
   "sources": [{"title": "Catalog, John Whitney, 1961. BAMPFA (Berkeley Art Museum and Pacific Film Archive) film collection", "url": "https://bampfa.org/node/192079"}, {"title": "Gene Youngblood, Expanded Cinema. New York: E. P. Dutton, 1970, pp. 208–213 (chapter “Computer Films”)", "url": "https://www.vasulka.org/Kitchen/PDF_ExpandedCinema/book.pdf"}, {"title": "William Moritz, “Digital Harmony: The Life of John Whitney, Computer Animation Pioneer”. Animation World Network, 1997", "url": "https://www.awn.com/animationworld/digital-harmony-life-john-whitney-computer-animation-pioneer"}],
   "related": {"notes":["john-whitney-digital-harmony","lissajous-figures-harmonograph","desmond-paul-henry-drawing-machines","jean-tinguely-meta-matics","spirograph-hypotrochoid"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/john-whitney-catalog-m5-director.jpg", "alt": "A black and white photograph from a 1944 army manual: a large metal box on a tall three-legged stand, with telescopes, round dials and handwheels on its sides. A heading reads Director, A.A., M5, M5A1 and M5A2.", "credit": "The M5 anti-aircraft director, the type of gun director whose mechanism Whitney converted; not Whitney's machine. Photo: US Army Signal Corps, technical manual TM 9-2300, 1944. Public domain, via Wikimedia Commons."},
   "text": "Catalog is a short abstract film by the American animator John Whitney (1917–1995), dated 1961. It runs just under seven minutes, on 16 mm colour film with sound, and shows squares, spirals and circles of points that appear, turn and merge. As the title says, it is a catalogue: a record of the effects Whitney had perfected on a mechanical analogue computer he built from a wartime anti-aircraft gun director.\n\nWhy it was made\n\nIn 1960 Whitney founded Motion Graphics Incorporated to make title sequences and commercials, much of it with his machine. He edited a sample reel of the effects he could produce, to show clients. It was released as Catalog and became, in the words of the film historian William Moritz, \"a popular classic of 1960's psychedelica\".\n\nThe machine\n\nIn the Second World War, anti-aircraft batteries were aimed by gun directors. Two men on a telescope table followed an enemy aircraft; analogue computers worked out the trajectory that would meet it and set the fuses of the shells, and motors aimed the guns.\n\nA decade later Whitney could buy such mechanisms as war surplus. An M-5 gun director was the basis of his first machine in the late 1950s; later he added the more sophisticated M-7 and combined the two into a device about twelve feet high. Instead of aiming a gun, the mechanism now moved artwork and camera:\n\ndesign templates lay on primary, secondary and tertiary rotating tables, with cam systems to program image and motion;\n\nthe tables spun on their own axes while also revolving around another axis and moving across the field of view;\n\nthe camera could itself turn or zoom, and the shutter could stay open for the whole of a movement or only part of it.\n\nWhitney's son John Jr. described the machine in 1970: the camera's input shaft turned at 180 rpm, but one frame took about nine seconds, because the secondary tables needed nine seconds to go round once, and during those nine seconds several motions ran at once. Moritz calls it a \"cam machine\" and credits it with pioneering motion control, the computer-steered camera movement later used in special effects. The film ends with a Lissajous curve repeated many times, a figure explained in the note on Lissajous figures.\n\nAfterwards\n\nIn 1966 IBM took Whitney on as artist in residence; Youngblood calls it the first major corporation to have one. From then on Whitney made his films with digital computers. The principle he worked out there, every element moving at its own whole-number multiple of one speed, is described in the note on John Whitney's Digital Harmony.\n\nOther machines that turned military calculators into drawing machines are described in Desmond Paul Henry's drawing machines; a mechanical drawing machine without any calculator is Tinguely's Méta-Matic. The wider history of art made from rules and systems is in JAEV's Generative Art."},
{"type": "note", "title": "Circle packing", "url": "https://jaev.gallery/notes/circle-packing/",
   "description": "Circle packing fills an area with circles that never overlap: the densest packing, the Apollonian gasket, the random method artists use, a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "circle packing", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5121501"}], "mentions": [{"name": "Apollonian gasket", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1184368"}, {"name": "Tyler Hobbs", "type": "Person", "sameAs": null}],
   "sources": [{"title": "“Circle packing”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Circle_packing"}, {"title": "“Apollonian gasket”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Apollonian_gasket"}, {"title": "Tyler Hobbs, “A Randomized Approach to Circle Packing”, 2 May 2016", "url": "https://www.tylerxhobbs.com/words/a-randomized-approach-to-circle-packing"}, {"title": "Tyler Hobbs, “Flow Fields”, 3 February 2020", "url": "https://www.tylerxhobbs.com/words/flow-fields"}],
   "related": {"notes":["poisson-disc-sampling","flow-fields","voronoi-delaunay","line-hatching"],"editorial":["generative-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/circle-packing-jaev.jpg", "alt": "A rectangle on warm paper filled with circles of many sizes that do not overlap: a few large ones, more middle-sized ones, and many small ones in the gaps. Each circle is drawn as a set of thin concentric black rings.", "credit": "Drawing by JAEV: circles of seven sizes placed largest first at random positions, each kept only if it overlaps nothing, after the randomized method Tyler Hobbs describes; each filled with concentric rings. CC BY 4.0."},
   "text": "Circle packing is the arrangement of circles in an area so that none of them overlap. In mathematics it is a question about how tightly circles can fit; in generative art it is a way of filling a sheet with shapes that are spread out evenly without lying on a grid.\n\nThe densest packing\n\nIf all the circles are the same size, the tightest arrangement is hexagonal: every circle touches six others, as in a honeycomb. The circles then cover π/(2√3), about 90.69 per cent, of the plane. Joseph-Louis Lagrange proved in 1773 that this is the densest packing among regular, lattice arrangements; Axel Thue published a proof in 1890 that it is the densest of all, and László Fejes Tóth gave the first rigorous proof in 1942.\n\nCircles in the gaps\n\nWith circles of different sizes, the gaps can be filled again and again. The classic case is the Apollonian gasket. Start with three circles that touch each other. In every gap between three touching circles, place a new circle that touches all three, and repeat for ever.\n\nThe finished gasket is a fractal: the circles never cover the whole area, and what is left has a dimension of about 1.31.\n\nThe random method\n\nA simpler way is trial and error, with no geometry of tangent circles. The artist Tyler Hobbs describes his method in \"A Randomized Approach to Circle Packing\" (2016):\n\nChoose the sizes of circle you want, and roughly how many of each.\n\nStart with the largest. Pick a random position and check whether the circle fits: it overlaps another circle if the distance between their centres is not larger than the two radii added together.\n\nIf it fits, keep it; if not, try another position. Hobbs gives up on a size after 2,000 failed attempts in a row, a balance, he writes, between speed and how dense the result becomes.\n\nMove on to the next size, ending with the smallest.\n\nBecause the large circles are placed first, the small ones end up in the gaps between them.\n\nNew drawing\nLive sketch by JAEV after the method Tyler Hobbs describes: seven sizes, from one circle of radius 160 to up to 600 of radius 8 on a square of 1,000 units, each placed at the first random position that overlaps nothing, with up to 2,000 tries per circle. The circles appear in the order they are placed. Code CC BY 4.0.\n\nAs a tool\n\nA packing is also a way of choosing points. The centres of the circles are spread evenly but irregularly, which is what Poisson disc sampling also aims for. Hobbs lists circle packing as one way of choosing where curves start in a flow field: \"things are pretty evenly spaced out\". On a plotter, each circle can be filled with lines, as with the concentric rings in the drawing at the top of this page; see line hatching and Plotter Art."},
{"type": "note", "title": "COLOR, Mikael Jern's raster program (Lund, 1970s)", "url": "https://jaev.gallery/notes/color-program-mikael-jern/",
   "description": "COLOR was the software that turned data into dots for the Hertz ink-jet plotter in Lund. How it made tones, solved hidden surfaces and led to UNIRAS.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Mikael Jern", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63869789"}], "mentions": [{"name": "Bo Ljungberg", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19352454"}, {"name": "Holger Bäckström", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5591690"}, {"name": "Carl Hellmuth Hertz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q77580"}, {"name": "Lund University", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q218506"}, {"name": "Applicon", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q4781517"}, {"name": "UNIVAC 1108", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2467608"}],
   "sources": [{"title": "Thomas Larsson and Ulf Stenlund, “Vignettes of Sweden's Computer Graphics History”. IEEE Annals of the History of Computing, 2008", "url": "https://www.es.mdu.se/pdf_publications/1105.pdf"}, {"title": "Lisa Adang, “The Aesthetics of the Color Plotter”. Cooper Hewitt, Smithsonian Design Museum, 8 May 2018 (first published 29 October 2016)", "url": "https://www.cooperhewitt.org/2018/05/08/aethetics-of-the-color-plotter/"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}, {"title": "Anna Orrghen, Från matematikmaskin till IT. Fokusgrupp: Media. Slutrapport. Tekniska museet, Stockholm, 2008", "url": "https://www.tekniskamuseet.se/app/uploads/2016/11/slutrapport-media-anna-orrghen.pdf"}, {"title": "“Computer Graphics: A Quarterly Report of SIGGRAPH-ACM”, Spring 1977, vol. 11, no. 1. ACM SIGGRAPH History Archives", "url": "https://history.siggraph.org/?p=65122"}],
   "related": {"notes":["hertz-ink-jet-colour-plotter","beck-and-jung","rgb-colour-cube"],"editorial":["the-colour-cubes","computer-art-in-sweden"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/color-program-mikael-jern-jaev.jpg", "alt": "Four rows of seventeen small grids of four by four dots on warm paper. From left to right each grid fills up one dot at a time, from empty to full: in cyan, in magenta, in yellow, and in the last row the three inks printed on the same dots, which comes out black.", "credit": "Diagram by JAEV: seventeen tones from a four-by-four dot matrix, in cyan, magenta, yellow and all three together. The order in which the dots are filled is JAEV's choice; Jern's own patterns are not known to us. CC BY 4.0."},
   "text": "COLOR was the software that Mikael Jern wrote at Lund University's computing centre in the 1970s to drive Hellmuth Hertz's ink-jet colour plotter. It turned data into a grid of coloured dots, ran on a UNIVAC 1108, was sold with the plotter to the American company Applicon, and became the starting point of Jern's company UNIRAS.\n\nBefore the plotter\n\nJern, a mathematics student, started as a night operator at the computing centre in 1968. Before there was a colour plotter he made maps on the line printer for town planning research: by printing the letters a, b and c on top of each other in the same place he got darker and lighter greys, with the program SIMAT.\n\nHow it works\n\nTones from dots. The plotter could only print a dot of ink or leave it out. To get lighter and darker tones, Jern grouped the dots in squares of four by four. The more of the sixteen dots are printed, the stronger the colour. With none to sixteen dots, each ink has seventeen levels, which matches the cube it drew: 17 × 17 × 17 small cubes.\n\nPart of the picture at a time. An A4 image was millions of dots; the computer had 64–128 KB of memory. Jern wrote a paging system that kept only the active part of the image in memory and wrote the result to magnetic tape, line by line, for the plotter.\n\nHidden surfaces. In three-dimensional pictures, surfaces behind other surfaces must not show. With line drawings this was one of the hardest problems in computer graphics. On a raster it can be solved by drawing the far objects first and letting the near ones paint over them, the \"painter's algorithm\". Jern cut holes and slices out of the colour cube to show that raster graphics could do what line graphics could not.\n\nA toolbox, not an application. COLOR was a set of FORTRAN subroutines. Users wrote short FORTRAN programs of their own that called them to draw, for example, a contour map or a 3D map. It was installed on computers in the United States, Canada and Australia; users posted tapes to Lund and got prints back by post, so one round could take weeks. In spring 1977 SIGGRAPH's journal Computer Graphics printed a paper by Jern titled \"Color Jet Plotter\".\n\nWhat it was used for\n\nMostly data: population maps with Statistics Sweden, contour maps, seismic images for oil companies, and in 1973 maps of metals in the river Vegeå. Jern dates his colour cube to 1972; Cooper Hewitt dates it to 1979. The artists Beck & Jung later used the program, run for them by the programmer Bob Wissler, and Cooper Hewitt holds their The Chromo Cube (1980), credited \"after software developed by Mikael Jern\". Who made the cubes is discussed in The colour cubes, and Olof Broström's Automatic Colour Cubes at JAEV brings such cubes together with Sol LeWitt's Incomplete Open Cubes.\n\nApplicon and UNIRAS\n\nThe plotter and COLOR went to Applicon. Jern's account has the contracts signed in 1976, with the software sold for about 60,000 dollars. Jern moved to Boston in 1979. When raster screens appeared, Applicon did not want the software adapted to them, and Jern left; with the Danish geophysicist Jan G. Knudsen he founded UNIRAS (Universal Raster System) in 1980. UNIRAS used the colour cube as its logo."},
{"type": "note", "title": "Computer Composition with Lines (A. Michael Noll, 1964)", "url": "https://jaev.gallery/notes/michael-noll-computer-composition-with-lines/",
   "description": "A. Michael Noll's Computer Composition with Lines and his 1966 test: 100 people compared it with a Mondrian. The rules, the results and a live sketch.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-24",
   "author": "JAEV Editorial",
   "about": [{"name": "A. Michael Noll", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4648184"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Piet Mondrian", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q151803"}, {"name": "Bell Labs", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q217365"}],
   "sources": [{"title": "A. Michael Noll, “Human or Machine: A Subjective Comparison of Piet Mondrian's ‘Composition With Lines’ (1917) and a Computer-Generated Picture”. The Psychological Record, 16, 1966, pp. 1–10. Scan", "url": "https://gwern.net/doc/culture/1966-noll.pdf"}, {"title": "A. Michael Noll, emails to JAEV, 22 and 23 October 2026", "url": "http://noll.uscannenberg.org/"}, {"title": "A. Michael Noll, “First-Hand: Early Digital Art at Bell Telephone Laboratories, Inc.”. Engineering and Technology History Wiki", "url": "https://ethw.org/First-Hand:Early_Digital_Art_At_Bell_Telephone_Laboratories%2C_Inc"}],
   "related": {"notes":["georg-nees-schotter","vera-molnar-interruptions","frieder-nake-hommage-a-paul-klee","generative-computergrafik-stuttgart-1965"],"editorial":["generative-art","plotter-art"],"exhibitions":["content"]},
   "image": {"url": "https://jaev.gallery/assets/notes/michael-noll-computer-composition-with-lines-and-mondrian-2.jpg", "alt": "Two pictures side by side. Left: A. Michael Noll's Computer Composition with Lines, short black vertical and horizontal bars inside a circle. Right: Piet Mondrian's painting Composition in Line, short black bars and crosses in a roughly circular field on a white canvas, signed PM 17.", "credit": "Left: A. Michael Noll, Computer Composition with Lines, 1964 (© A. Michael Noll 1965), shown with his written permission; scan supplied by Noll, cropped below the drawing. Right: Piet Mondrian, Composition in Line, 1916–17, Kröller-Müller Museum, Otterlo; public domain, via Wikimedia Commons."},
   "text": "Computer Composition with Lines is a picture made by A. Michael Noll at Bell Telephone Laboratories in Murray Hill, New Jersey, after Piet Mondrian's painting Composition With Lines (1917). Noll then showed both pictures to 100 people and asked which one the computer had made. Most of them got it wrong, and most preferred the computer's picture.\n\nThe painting\n\nMondrian's black-and-white painting is a scatter of short vertical and horizontal bars. Noll noted three things about it: its outline is a circle cropped at the sides, top and bottom; the bars in a region at the top are shorter; and otherwise the length and width of the bars seem randomly distributed. He also wrote that Mondrian placed each bar with \"considerable planning\", although \"the exact algorithm is unknown\".\n\nHow the computer picture was made\n\nAn IBM 7094 computer calculated the picture, and an SC-4020 microfilm plotter drew it on the face of a cathode ray tube, where a 35 mm camera photographed it. Each bar was a set of parallel line segments spaced closely enough to overlap. Noll published the rules:\n\nthe bars are placed at random inside a circle of radius 450 units, every location equally likely;\n\nvertical and horizontal are equally likely;\n\nthe width is between 7 and 10 lines, the length between 10 and 60 points, all values equally likely;\n\nif a bar falls inside a parabolic region at the top, its length is reduced by a factor proportional to its distance from the edge of the parabola.\n\nReconstruction by JAEV after the rules A. Michael Noll published in 1966: bars placed at random in a circle, shorter inside a parabola at the top, each bar drawn as parallel lines. The dashed circle and the red parabola show the rule; the number of bars and the parabola are JAEV's, not the original. CC BY 4.0.\n\nThe shape of the parabola and the factor were found by trial and error, until the effect was \"reasonably similar\" to Mondrian's. Noll copied Mondrian's outline and the shorter bars at the top, and replaced the planned placement with chance.\n\nLive sketch\n\nNew drawing\nSketch by JAEV after the rules in Noll's 1966 paper: bars at random in a circle of radius 450, vertical or horizontal, width 7–10 lines, length 10–60 points, shorter inside a parabola at the top. The paper does not give the number of bars, the size of a \"line\" or a \"point\", or the parabola, so these are JAEV's choices. Not the original program and not the work. Code CC BY 4.0.\n\nThe Mondrian test\n\nNoll had both pictures copied xerographically so that they looked equally good, labelled them A and B in alternating order, and gave them to 100 people, all but two of them Bell Labs employees. Each answered which picture they thought the computer had drawn and which they preferred.\n\n59% preferred the computer picture.\n\nOnly 28% identified the computer picture correctly.\n\nBoth results differed from chance at the 0.05 level. People who liked abstract art preferred the computer picture by more than three to one. Of the technical staff, 35% identified it, against 13% of the non-technical staff. Noll's explanation was that the non-technical group expected a computer to make orderly pictures, and so took the Mondrian for the machine's work. The participants described the computer picture as \"neater\" and more \"varied\". The paper appeared in The Psychological Record in 1966.\n\nNoll's paper dates the picture 1964; his later account of early art at Bell Labs gives 1965. Noll told JAEV that the work was made in 1964, and that 1965 is the year of its copyright: it was first shown in public at the Howard Wise Gallery in New York in 1965, and copyright then began at the first public showing. The picture won first prize in a contest run by the magazine Computers and Automation in August 1965.\n\nJAEV's own Content also hands composition to a calculation: each day a SHA-256 hash of the day's text chooses its composition, shapes and colours."},
{"type": "note", "title": "Computer Technique Group (Tokyo, 1966–1969)", "url": "https://jaev.gallery/notes/computer-technique-group/",
   "description": "The Computer Technique Group was a Tokyo collective that made computer graphics with IBM machines from 1966 to 1969, among them Running Cola is Africa.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Computer Technique Group", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q55333336"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Cybernetic Serendipity", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5197816"}, {"name": "ZKM | Center for Art and Media Karlsruhe", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q191228"}],
   "sources": [{"title": "“CTG (Computer Technique Group)”. Electronic Arts Intermix, artist overview", "url": "https://www.eai.org/artists/ctg-computer-technique-group/titles"}, {"title": "“Computer Technique Group”. Science Museum Group Collection, people record", "url": "https://collection.sciencemuseumgroup.org.uk/people/cp167302/computer-technique-group"}, {"title": "Computer Technique Group, Running Cola is Africa, 1967. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/artwork/running-cola-is-africa"}, {"title": "“CTG (Computer Technique Group)”. NTT InterCommunication Center [ICC], archive", "url": "https://www.ntticc.or.jp/en/archive/participants/ctg/"}, {"title": "“Cybernetic Serendipity: The Computer and the Arts”, Studio International special issue, ed. Jasia Reichardt, 1968. Contents", "url": "https://studiointernational.com/index.php/cybernetic-serendipity-the-computer-and-the-arts"}],
   "related": {"notes":["cybernetic-serendipity","charles-csuri-hummingbird","calcomp-565","hiroshi-kawano"],"editorial":["plotter-art","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/computer-technique-group-jaev.jpg", "alt": "Five thin black outlines in a row on warm paper. The first is a square, the last an irregular rounded shape with lobes, and the three between change step by step from one to the other. Dashed red lines run straight through the row, following a few points from the square to the final shape.", "credit": "Diagram by JAEV of the method behind a computer metamorphosis: two given outlines, a square and a curve of JAEV's own, and three steps computed between them by moving every point the same fraction of the way. Dashed red: the paths of a few points. Not a CTG work. CC BY 4.0."},
   "text": "The Computer Technique Group (CTG) was a collective in Tokyo that made computer graphics and films from December 1966 until it disbanded in November 1969. It was founded by Masao Komura, Haruki Tsuchiya, Kunio Yamanaka and Junichiro Kakizaki, and six more members joined later. Its best-known work is Running Cola is Africa.\n\nDesigners and engineers at IBM\n\nThe group worked with IBM Japan, at the IBM Scientific Data Centre in Tokyo, where it had a large computer and a plotter. According to the Science Museum Group, its office was at once a design studio, selling graphics to galleries, and a \"think tank with expertise in computer analysis\". Their works are credited by task: who had the idea, who prepared the data and who wrote the program. For Running Cola is Africa that was Komura, a product designer (idea), Makoto Ohtake (data) and Koji Fujino, a systems engineer (program).\n\nMetamorphoses\n\nCTG took familiar images, such as a running man, a woman's profile or John F. Kennedy, and changed them with geometric transformations calculated by the computer. Running Cola is Africa (1967–68) is number 3 in its Metamorphoses series. In the words of ZKM in Karlsruhe, \"A computer algorithm converts a running man into a bottle of cola\", and the bottle then becomes the outline of Africa. The program was written in Fortran IV for an IBM 7090 and drawn on a CalComp 563 plotter; the print is a lithograph made from the plotter drawing.\n\nThe diagram above shows the simplest way to compute such a change. Both outlines are described by the same number of points. For each step in between, every point moves the same fraction of the way, in a straight line, from its place in the first outline to its place in the second. The sources we read do not give CTG's exact formula, so the diagram shows the principle rather than their program.\n\nLondon, 1968\n\nIn 1968 CTG was shown in Cybernetic Serendipity at the Institute of Contemporary Arts in London, and the catalogue had a section on the \"Computer Technique Group from Japan\". The group's lithographs were published in London by Motif Editions; ZKM holds Running Cola is Africa. In 2005 the NTT InterCommunication Center in Tokyo showed CTG in Possible Futures: Japanese postwar art and technology."},
{"type": "note", "title": "Contour lines with marching squares", "url": "https://jaev.gallery/notes/marching-squares-contour-lines/",
   "description": "Marching squares draws contour lines through a grid of values: four corners, sixteen cases, one lookup table. How it works, and the saddle problem.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "marching squares", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1408282"}, {"name": "contour line", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q6653802"}], "mentions": [{"name": "marching cubes", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1886184"}],
   "sources": [{"title": "“Marching squares”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Marching_squares"}, {"title": "“Marching cubes”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Marching_cubes"}, {"title": "Jamie Wong, “Metaballs and Marching Squares”, 19 August 2014", "url": "https://jamie-wong.com/2014/08/19/metaballs-and-marching-squares/"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}],
   "related": {"notes":["perlin-noise","color-program-mikael-jern","plotter-path-optimisation","line-hatching"],"editorial":["generative-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/marching-squares-contour-lines-jaev.jpg", "alt": "Two squares on warm paper. Left: a grid of 11 by 11 points, black dots where a height field is above a chosen height and open circles where it is below, with a red line winding between the black and the open ones. Right: the same field as thin black contour lines around two hills, with the same red line among them. Small grey labels under each.", "credit": "Diagram by JAEV: a made-up height field of five round hills. Left: measured at the corners of a 10 × 10 grid; black dots above the chosen height, open circles below, and in red the contour that marching squares draws between them. Right: the same field on a 120 × 120 grid, contoured at 14 heights, the left one in red. CC BY 4.0."},
   "text": "Marching squares is an algorithm that draws contour lines through a grid of measured values, such as heights, temperatures or air pressure. It looks at one small square of the grid at a time, decides from its four corners which of sixteen cases it is, and draws a short line across it; together the short lines form the contours. It is the two-dimensional version of marching cubes, which Lorensen and Cline published in 1987 after research for General Electric on showing CT and MRI scans.\n\nHow it works\n\nStart with values on a grid, for instance heights measured every ten metres, and choose one height, say 50 metres. The contour at 50 metres separates the ground above it from the ground below.\n\nAbove or below. Mark every grid point 1 if it is above 50 and 0 if it is below.\n\nSixteen cases. Take a square of four neighbouring points. Read their four marks in a fixed order, going round the square, as a four-digit binary number. There are sixteen possibilities, from 0000 to 1111.\n\nThe lookup table. A table with sixteen entries says which sides of the square the contour crosses. In case 0000 or 1111 all four corners are on the same side, and nothing is drawn. If one corner is above and three are below, the contour cuts off that corner.\n\nWhere on the side. Without more, every line would cross the sides at their midpoints and the contour would look blocky, made of 45-degree steps. Instead the crossing point is found by assuming that the value changes evenly between two corners. If one corner is at 30 metres and the next at 70, the 50-metre line crosses halfway; if they are at 40 and 90, it crosses a fifth of the way from the lower one.\n\nEvery square is handled on its own, from its four corners and the table. Repeating it for several heights gives a contour map. Lines of one value are called isolines; filled areas between two values are isobands.\n\nNew drawing\nSketch by JAEV: a random field of five round hills. Left: a 16 × 16 grid with dots at the corners above one height, and the contour marching squares draws for it. Right: the same field on a 64 × 64 grid, contoured at ten heights, with the left one thicker. Code CC BY 4.0.\n\nThe saddle\n\nTwo cases are ambiguous: when diagonally opposite corners are above and the other two below. The contour could then separate the two high corners or join them across the middle. A common answer is to take the average of the four corners as the value at the centre and let that decide. Some programs simply always choose one way.\n\nWhere it is used\n\nContour lines on topographic maps and isobars on weather maps are the classic uses. In Lund in the 1970s, Mikael Jern's COLOR program was used above all for contour maps, printed in colour on the Hertz ink-jet plotter. The interview does not say how the contours were computed. In generative art the method draws the contours of a made-up field: the sketch in the note on Perlin noise uses it.\n\nFor a pen plotter, the result is thousands of short segments, which have to be joined end to end and put in order before they are drawn; see plotter path optimisation."},
{"type": "note", "title": "Conway's Game of Life (1970)", "url": "https://jaev.gallery/notes/game-of-life/",
   "description": "The Game of Life: John Conway's 1970 grid of cells that live, die and are born by three rules. The rules as first published, the glider, a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Conway's Game of Life", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q244615"}], "mentions": [{"name": "John Horton Conway", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q268961"}, {"name": "Martin Gardner", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q677706"}],
   "sources": [{"title": "Martin Gardner, “Mathematical Games: The fantastic combinations of John Conway's new solitaire game “life””. Scientific American 223, October 1970", "url": "https://web.stanford.edu/class/sts145/Library/life.pdf"}, {"title": "“Conway's Game of Life”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life"}],
   "related": {"notes":["boids-craig-reynolds","diffusion-limited-aggregation","reaction-diffusion","ten-print-maze"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/game-of-life-jaev.jpg", "alt": "A grid of faint grey dots on warm paper with clusters of small squares. Black squares are cells that survive into the next generation, red squares are cells being born, and open black outlines are cells about to die.", "credit": "Drawing by JAEV: one generation of the Game of Life after 60 generations from a random field, marked as Martin Gardner's 1970 column tells players to mark it: survivors black, births red, deaths open. CC BY 4.0."},
   "text": "The Game of Life is a grid of cells, each either alive or empty, that changes in steps by three rules about neighbours. The British mathematician John Horton Conway devised it in 1970, and Martin Gardner made it known in his \"Mathematical Games\" column in Scientific American in October that year.\n\nThe rules\n\nGardner presented it as a game for one person with a large checkerboard and flat counters of two colours. Each cell has eight neighbours, four beside it and four on the diagonals. Conway's \"genetic laws\", as the column calls them:\n\nSurvivals. \"Every counter with two or three neighboring counters survives for the next generation.\"\n\nDeaths. A counter with four or more neighbours dies from overpopulation; one with one neighbour or none dies from isolation.\n\nBirths. \"Each empty cell adjacent to exactly three neighbors – no more, no fewer – is a birth cell.\"\n\n\"It is important to understand that all births and deaths occur simultaneously.\" To keep them apart on the board, Conway put a black counter on every cell about to die and a white one on every birth cell, checked the board, and only then cleared the dead and turned the white counters black. The picture at the top of this page marks one generation the same way.\n\nConway chose the rules after long experiment, aiming for a result that would be hard to predict: there should be no simple proof that a pattern can grow without limit, some patterns should seem to grow without limit, and simple patterns should change for a long time before they die out, settle, or start repeating.\n\nNew drawing\nLive sketch by JAEV: a field of 96 × 60 cells, about one in three alive at the start, run by Conway's three rules at roughly ten generations a second. The field wraps round, so a shape leaving one edge comes back at the other. Code CC BY 4.0.\n\nWhat the rules make\n\nMost random starts end in \"still lifes\", shapes that no longer change, or in oscillators that repeat for ever, such as the \"blinker\", a row of three cells that turns from horizontal to vertical and back. Some take very long: Conway followed the five-cell R pentomino for 460 generations without learning its fate.\n\nThe best-known shape is the glider: five cells that after four generations have rebuilt themselves one cell further along the diagonal.\n\nConway guessed that no pattern could grow without limit and offered $50 to the first person to prove or disprove it before the end of 1970. In November a team at MIT led by Bill Gosper won the prize with a glider gun. Life has since been shown to be Turing-complete: in principle, a large enough pattern can carry out any computation a computer can.\n\nA rule, not a picture\n\nLife is a cellular automaton: nothing in it is drawn, only the rule is written, and every shape on the grid follows from the starting cells. That makes it a close relative of other rule systems in these notes, such as Boids, where flocks appear from three rules per bird, and diffusion-limited aggregation. See also Generative Art."},
{"type": "note", "title": "Cubic Limit (Manfred Mohr, 1973–75)", "url": "https://jaev.gallery/notes/manfred-mohr-cubic-limit/",
   "description": "In Cubic Limit (1973–75) Manfred Mohr used the twelve edges of a cube as an alphabet: subsets of lines, rotation, all combinations. With a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}],
   "sources": [{"title": "Manfred Mohr, “Cubic Limit, Generative Drawings, Part 1. Travaux de 1973–1975”, Galerie Weiller, Paris, 1975. emohr.com", "url": "https://www.emohr.com/paris-1975/index.html"}, {"title": "Manfred Mohr, “50 Year Celebration: Time Line”. emohr.com", "url": "https://www.emohr.com/ManfredMohr_50YearCelebration_TimeLine.html"}, {"title": "Manfred Mohr, “Cubic Limit I – 1973–1975 and parts of Cubic Limit II – 1976–1977”. emohr.com", "url": "https://www.emohr.com/cubic_limit_1.html"}, {"title": "“P-161 Cubic Limit”. ACM SIGGRAPH History Archives", "url": "https://history.siggraph.org/?p=20410"}, {"title": "Manfred Mohr, “Computer generated films”. emohr.com", "url": "https://www.emohr.com/collab-exp/col_mohr-film.html"}, {"title": "“Automatic Colour Cubes”, Olof Broström. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/automatic-colour-cubes/"}],
   "related": {"notes":["benson-plotter","sol-lewitt-instructions-as-algorithms","rgb-colour-cube","algorists-verostko"],"editorial":["manfred-mohr","sol-lewitt","plotter-art"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/manfred-mohr-cubic-limit-jaev.jpg", "alt": "Two rows of six cubes drawn in thin lines on warm paper, each turned a little further than the one before. In the top row only five of each cube's twelve edges are black and the rest are faint grey; in the bottom row the other seven edges are black. A red arrow under the rows points to the right.", "credit": "Diagram by JAEV of the method Manfred Mohr describes: a subset of a cube's twelve edges (top) and the other edges (bottom) while the cube turns. Our own subset and angles, not a work by Mohr. CC BY 4.0."},
   "text": "Cubic Limit is a series of drawings, etchings and films that Manfred Mohr made in Paris from 1973 to 1975. It is the first work in which he used one fixed structure, a cube, and treated its twelve edges as an alphabet: \"The 12 edges of the cube became my alphabet to which I apply algorithms.\" Almost everything below comes from Mohr's own pages on the series.\n\nThe alphabet\n\nA cube has eight corners and twelve edges. Mohr's programs choose a subset of the twelve lines and draw only that subset, and the familiar object becomes a sign that is hard to read as a cube. He had worked the same way with the lines of squares and triangles the year before, in 1972; Cubic Limit moved the idea to three dimensions and added rotation: as the cube turns, the chosen lines are projected onto the paper at each new angle.\n\nMohr lists the operations he used in the series:\n\nseries of all combinations of a given number of lines, n at a time;\n\noperations from symbolic logic applied to sets of lines;\n\nclusterings of elements;\n\ncomplementary elements: a set of lines next to the lines it leaves out;\n\ndiagrams that explain the process, with numbers alongside the lines.\n\nAll combinations\n\nIn 1975 Mohr showed \"all combinations of n-lines of cube at time in series of 13 drawings\". The work is P-161. The arithmetic is simple. From twelve edges one can choose none, one, two and so on up to all twelve: thirteen possible values of n. The number of different subsets grows quickly towards the middle: 12 ways to pick one line, 66 to pick two, 924 to pick six, and 4,096 subsets in all. A work from 1974 called Pascal Triangle arranges cube lines from 1 to 12 in circles that are summed into the circle above, the scheme by which those counts are built.\n\nThe SIGGRAPH archive lists P-161 Cubic Limit as a plotter drawing of 38.5 × 153 inches and dates it 1973; Mohr's own list dates it 1975.\n\nLive sketch\n\nNew drawing\nSketch by JAEV of the method, not of a work: eight cubes, each turned to a random angle and drawn with only some of its twelve edges. Read them in pairs: the left cube shows a random set of edges, the right cube at the same angle shows exactly the edges that were left out, the complementary set. The number of edges, the sets and the angles are random and ours; Mohr's own rules for choosing are not reproduced. Code CC BY 4.0.\n\nDrawings, etchings, films\n\nIn these years Mohr drew at night on the Benson plotter of the French weather service in Paris, which he used from 1970 to 1983. For the etchings of 1975 he \"replaced the pen on the plotter with a steel needle and drew on a treated copper plate\"; the first hundred copies of the catalogue each contained one.\n\nThe 16 mm film Cubic Limit (1973–74, around four minutes) was made on a Datagraphix 4460 belonging to the firm C.G.M.: \"each frame, generated by the algorithm, was drawn with a light beam on a small high resolution screen\" and photographed onto film. Complementary Cubes (around five and a half minutes) shows two rotating cubes, one with n edges and the other with the remaining 12 minus n.\n\nWhere it was shown\n\nThe series opened at Galerie Weiller in Paris on 29 May 1975, and the show was extended to 15 July. Michel Conil Lacoste reviewed it in Le Monde on 3 July. It then travelled to five more galleries in 1975–76. What came after, the cut cubes of Cubic Limit II and the hypercube, is told in JAEV's editorial on Mohr, which also compares his cubes with Sol LeWitt's of 1974. Olof Broström's Automatic Colour Cubes at JAEV uses a cube in another way: each of its 122 works opens a colour cube along the edges that one of LeWitt's 122 Incomplete Open Cubes leaves out (see the RGB colour cube)."},
{"type": "note", "title": "Cybernetic Serendipity (ICA, London, 1968)", "url": "https://jaev.gallery/notes/cybernetic-serendipity/",
   "description": "Cybernetic Serendipity, curated by Jasia Reichardt at the ICA in London in 1968, showed computer art, music, poetry and machines. What was in it.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Cybernetic Serendipity", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5197816"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Jasia Reichardt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4974363"}, {"name": "Institute of Contemporary Arts", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1665153"}, {"name": "Gordon Pask", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q370461"}, {"name": "Edward Ihnatowicz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5343589"}, {"name": "Corcoran Gallery of Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q768446"}, {"name": "Exploratorium", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q206518"}],
   "sources": [{"title": "“Cybernetic Serendipity”, documentation display, 14 October – 30 November 2014. Institute of Contemporary Arts, archive", "url": "https://archive.ica.art/node/40494"}, {"title": "“Cybernetic Serendipity: The Computer and the Arts”, Studio International special issue, ed. Jasia Reichardt, 1968. Contents", "url": "https://studiointernational.com/index.php/cybernetic-serendipity-the-computer-and-the-arts"}, {"title": "“Cybernetic Serendipity”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Cybernetic_Serendipity"}, {"title": "“SAM – Sound Activated Mobile”. Alex Zivanovic, senster.com", "url": "https://www.senster.com/ihnatowicz/SAM/sam.htm"}, {"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal, Spring 2009", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}],
   "related": {"notes":["tendencies-4-zagreb","desmond-paul-henry-drawing-machines","computer-technique-group","knowlton-harmon-studies-in-perception","edward-ihnatowicz-senster"],"editorial":["plotter-art","there-should-be-no-computer-art","generative-art","georg-nees"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/cybernetic-serendipity-jasia-reichardt-2022.jpg", "alt": "Jasia Reichardt, an older woman with curly brown hair, a dark sweater and a patterned red and black scarf, in front of grey filing cabinets with small toy robots on top.", "credit": "Jasia Reichardt, who curated Cybernetic Serendipity, in a Studio International interview at the Themerson Archive, London, February 2022. Still: Studio International, CC BY 3.0, via Wikimedia Commons."},
   "text": "Cybernetic Serendipity, an exhibition about the computer and the arts, ran at the Institute of Contemporary Arts (ICA) in London from 2 August to 20 October 1968. It was curated by the critic Jasia Reichardt and showed computer graphics, music, poetry, films and machines by more than 130 people. The ICA calls it the first international exhibition in Britain on the arts and new technology.\n\nThe idea\n\nThe participants were not only artists but also composers, engineers, mathematicians and poets. The aim, in the ICA's account, was to show the links between the random systems that artists, composers and poets used and the cybernetic devices they worked with, and to show possibilities rather than finished achievements.\n\nWhat was in it\n\nThe catalogue was a special issue of Studio International, published in July 1968.\n\nMachines. Gordon Pask's Colloquy of Mobiles, Edward Ihnatowicz's Sound Activated Mobile, which turned toward quiet, steady sounds, Jean Tinguely's painting machines and Nam June Paik's Robot K-456. The catalogue section on machines also had \"The Henry drawing computer\" by Desmond Paul Henry and Ivan Moscovich's \"pendulum harmonograph\", a drawing machine of the kind described in Lissajous figures.\n\nMusic. Visitors could sing or whistle into a microphone and hear Peter Zinovieff's equipment improvise on the tune.\n\nFilms. John Whitney's Permutations and a film from Bell Labs.\n\nGraphics. Contributions by Frieder Nake, Georg Nees and A. Michael Noll, Harmon and Knowlton, the Computer Technique Group from Japan, an interview with Charles Csuri, and a section on the CalComp plotting system.\n\nVisitors and tour\n\nThe ICA gives some 60,000 visitors. Wikipedia notes that Time magazine reported 40,000 and that the ICA did not count accurately. In 1969 the exhibition travelled to the Corcoran Annex of the Corcoran Gallery of Art in Washington, D.C. (16 July – 31 August) and then to the Exploratorium in San Francisco (1 November – 18 December).\n\nLondon and Zagreb\n\nOne day after the London opening, on 3 August 1968, Zagreb held the colloquy Computers and Visual Research, part of Tendencies 4. Frieder Nake, who wrote for the London catalogue, later put the difference in two phrases: London was \"art as an event\", Zagreb \"art as research\". Nake's later rejection of the whole label is told in There should be no computer art, and JAEV's Plotter art places Cybernetic Serendipity among the exhibitions that defined the field."},
{"type": "note", "title": "Datasaab and Swedish computer art (D2, D21, D22)", "url": "https://jaev.gallery/notes/datasaab-and-swedish-computer-art/",
   "description": "Which Swedish artists used Datasaab computers in the 1960s, and how: Neutron Star, Supersonics and the Lund picture, all through one engineer.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Datasaab", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q4346791"}, {"name": "SAAB D21", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q65244000"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Datasaab D2", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5227493"}, {"name": "Göran Sundqvist", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19885695"}, {"name": "Jan W. Morthenson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1147400"}, {"name": "Lars-Gunnar Bodin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5580344"}, {"name": "Skandinaviska Elverk", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q31890382"}, {"name": "Tektronix", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1347679"}, {"name": "ABC 80", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q287115"}],
   "sources": [{"title": "DataSaab D21 (TEKS0041633). Tekniska museet, Stockholm, on DigitaltMuseum", "url": "https://digitaltmuseum.se/021026305322/datamaskin"}, {"title": "Göran Sundqvist, interviewed by Anna Orrghen, 31 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/5-goran-sundqvist.pdf"}, {"title": "Jan W Morthenson, interviewed by Anna Orrghen, 17 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/6-jan-w-morthenson.pdf"}, {"title": "Göran Sundqvist, “Fossil II”, “Spirals”, “Fire Bird”. Eighth Annual Computer Art Contest, Computers and Automation, August 1970, p. 20", "url": "https://bitsavers.org/magazines/Computers_And_Automation/197008.pdf"}, {"title": "Anna Orrghen, Från matematikmaskin till IT. Fokusgrupp: Media. Slutrapport. Tekniska museet, Stockholm, 2008", "url": "https://www.tekniskamuseet.se/app/uploads/2016/11/slutrapport-media-anna-orrghen.pdf"}],
   "related": {"notes":["jan-w-morthenson","lars-gunnar-bodin","ibm-1130-swedish-computer-art","ems-elektronmusikstudion","tektronix-4010"],"editorial":["computer-art-in-sweden"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/datasaab-d21-tekniska-museet.jpg", "alt": "Black-and-white photo of a computer room: tall grey cabinets with magnetic tape reels behind glass, labelled DATASAAB D21, a desk console with rows of number displays and push-buttons in front, and an electric typewriter on the right.", "credit": "The Datasaab D21 at Tekniska museet, Stockholm, where it was shown in running condition. Photo: Tekniska museet, CC BY 4.0, via Wikimedia Commons."},
   "text": "Datasaab was the computer branch of the Swedish aircraft maker Saab in Linköping. It built the transistorised D2 in 1960 and its first mainframe, the D21, in 1962; 32 D21s were sold to companies and government agencies. In the published sources, Swedish artists used Datasaab machines in the 1960s only through one engineer, Göran Sundqvist, and one customer's computers in Stockholm. This note covers what is documented.\n\nThe D2: a demonstration\n\nAt SAAB around 1960–61, Sundqvist was asked to impress visiting air force officers. On the D2, a prototype for an aircraft computer, he drew the path of a cannonball on an oscilloscope, with dials for the gun, and went on for years making pictures with it that he photographed off the screen. More in Computer Art in Sweden.\n\nSEVED: a power company's D21\n\nIn spring 1962 a D21 was delivered to the power company Skandinaviska Elverk in Stockholm, and Sundqvist came with it as its technician: \"I was part of the purchase.\" It was called SEVED, for Skandinaviska Elverks Elektroniska Datamaskin. Its real job, Morthenson says, was to regulate the gates of hydroelectric dams by the demand for power.\n\nThe D21 could make sound. A loudspeaker was connected to a register, so that switching it 440 times a second gave the note A. Sundqvist programmed the musical dice game attributed to Mozart, with a random generator in place of the dice. Composers from the music society Fylkingen came to him:\n\nJan W. Morthenson, Neutron Star (1967): short pulses from a random generator, written in assembler on the D21. See Jan W. Morthenson.\n\nMorthenson, Supersonics (1969) for West German television: figures that Morthenson drew, built up on a Tektronix 611 storage oscilloscope driven by the D21, filmed from an outside-broadcast bus parked outside the office.\n\nLars-Gunnar Bodin, the 1968 Lund picture: cells with random numbers of elements, printed on the line printer and painted by hand. Sundqvist remembers that the printed text said it was made possible \"through the courtesy of Datasaab\". See Lars-Gunnar Bodin.\n\nThe D22 and the pictures of 1970\n\nFrom 1969 the company, now Kraftdata, had a D22. Between 7 and 8 in the morning, during maintenance, Sundqvist could use the processor with a Tektronix 611, and photographed what he drew. In August 1970 Computers and Automation printed three of the pictures, Fossil II, Spirals and Fire Bird, \"taken from a Tektronix 611 display terminal connected to a SAAB D22 computer\", made \"from a simple program to produce a circle\". It ended in 1972, when terminals came in and the computer had to run around the clock.\n\nWhat is not documented\n\nAnna Orrghen's survey of where Swedish artists met computers names SAAB among eight places. We found no artist who worked with Datasaab directly, and no work made on its computers after 1972. Sundqvist's later plotter work for Bodin was on a Swedish microcomputer from Luxor, an ABC 80, with an XY plotter; he was unsure whether that was before 1980. The other route to a computer, through IBM, is in The IBM 1130 and Swedish computer art."},
{"type": "note", "title": "Design by Numbers (John Maeda, 1999)", "url": "https://jaev.gallery/notes/design-by-numbers/",
   "description": "Design by Numbers, John Maeda's small language from MIT (1999) for teaching designers to draw with code: Paper, Pen, Line, Repeat. With a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Design By Numbers", "type": "SoftwareApplication", "sameAs": "https://www.wikidata.org/wiki/Q5264253"}], "mentions": [{"name": "John Maeda", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q93024"}, {"name": "MIT Media Lab", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1373549"}, {"name": "Processing", "type": "SoftwareApplication", "sameAs": "https://www.wikidata.org/wiki/Q1053535"}, {"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}, {"name": "Ben Fry", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4888685"}],
   "sources": [{"title": "“What is DBN?”. Design By Numbers, MIT Media Laboratory", "url": "https://dbn.media.mit.edu/whatisdbn.html"}, {"title": "John Maeda, “An Introduction to DBN”. Design By Numbers, MIT Media Laboratory", "url": "https://dbn.media.mit.edu/introduction.html"}, {"title": "Ben Fry and Casey Reas, “Overview”. Processing.org", "url": "https://processing.org/overview"}, {"title": "Liz Stinson, “Processing: the Software that Shaped Creative Coding”. AIGA Eye on Design, 28 October 2021", "url": "https://eyeondesign.aiga.org/processing-the-software-that-shaped-creative-coding/"}, {"title": "“Design By Numbers”. MIT Media Laboratory, home page (last updated 2 August 2003)", "url": "https://dbn.media.mit.edu/"}, {"title": "John Maeda, “Design By Numbers”. maedastudio.com, 2005", "url": "https://maedastudio.com/1999/dbn/index.php"}],
   "related": {"notes":["processing","ten-print-maze","hp-gl","sol-lewitt-instructions-as-algorithms"],"editorial":["casey-reas","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/design-by-numbers-jaev.jpg", "alt": "Left: a square drawing area with the corner labels 0 0 at the lower left and 100 100 at the upper right. A hundred and one straight black lines fill its lower right corner and together form a concave curve. Right: the program that draws it, in black monospace type: Paper 0, Pen 100, Repeat A 0 100, Line A 0 100 A.", "credit": "Diagram by JAEV, laid out like the DBN environment with the drawing on the left and the program on the right: a four-line DBN program (JAEV's own example, using only commands from Maeda's introduction) and the drawing it makes. CC BY 4.0."},
   "text": "Design by Numbers (DBN) is a small programming language and editor that John Maeda made at the MIT Media Lab and released in 1999. It was meant for visual designers and artists who had never programmed: every program draws a picture, and the numbers lie, as a rule, between 0 and 100. It was also the direct ancestor of Processing.\n\nFour commands\n\nMaeda's own introduction starts with three commands, each followed by numbers:\n\nPaper 50 covers the drawing area in 50% black, a middle grey. Paper 0 is white, Paper 100 black.\n\nPen 100 sets the pen to 100% black; Pen 0 is a white pen.\n\nLine 0 0 100 100 draws a line between two points, from the lower left corner (0 0) to the upper right corner (100 100).\n\nThe fourth, Repeat, runs the commands inside its braces again and again while a variable counts. In Maeda's example, Repeat A 0 100 { Pen A Line A 0 A 100 } draws 101 vertical lines, each a little darker than the one before, from white on the left to black on the right. The program in the picture above uses the same four commands: Line A 0 100 A joins a point moving along the bottom edge to a point moving up the right edge, and the 101 straight lines together make a curve.\n\nOn screen the drawing sat on the left and the program on the right, as in the picture. The language added variables and conditions to these drawing commands, but it was deliberately not a general-purpose language like C or Java. Ben Fry later called it \"under-featured, and intentionally so\".\n\nLive sketch\n\nNew drawing\nSketch by JAEV: a tiny interpreter for Paper, Pen, Line and Repeat as Maeda's introduction describes them, with (0 0) at the lower left. Each new drawing writes a new short DBN program from random numbers, shows it below the drawing and runs it. Pen values become shades of the page's text colour. Not the original DBN software, which ran in Java. Code CC BY 4.0.\n\nThe project\n\nDBN came with three parts: the software, which ran in a web browser or could be downloaded; a book, Design by Numbers, from MIT Press; and courseware for teachers. Maeda made version 1.0. Ben Fry made versions 2 and 3, and Casey Reas wrote the courseware; the last version, 3.0.1, is still offered on the MIT site.\n\nMaeda wrote in 2005 that he made DBN at a time when getting artists and designers to program \"was just beginning to become in vogue\", and that \"The actual point of the book was to get more non-programmers to program as a means to hopefully realize how boring programming can be\" – and then to imagine a better kind of programming. Fry and Reas, who looked after DBN, \"felt that they had the right designs for a new solution\". Processing, which they started in 2001, \"grew directly out of\" DBN. Pen plotters take short commands with numbers telling them what to draw, as in HP-GL, much like DBN."},
{"type": "note", "title": "Desmond Paul Henry's drawing machines (1961–1967)", "url": "https://jaev.gallery/notes/desmond-paul-henry-drawing-machines/",
   "description": "In the 1960s the Manchester philosopher Desmond Paul Henry built drawing machines from wartime bombsight computers. How they worked and where they went.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Desmond Paul Henry", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5264783"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Cybernetic Serendipity", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5197816"}, {"name": "Victoria University of Manchester", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q867530"}, {"name": "Institute of Contemporary Arts", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1665153"}],
   "sources": [{"title": "“Desmond Paul Henry”. Computer Arts Society", "url": "https://computer-arts-society.com/cas/desmond-henry.html"}, {"title": "“Desmond Paul Henry”. Science Museum Group Collection, people record", "url": "https://collection.sciencemuseumgroup.org.uk/people/cp167600"}, {"title": "“Desmond Paul Henry”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Desmond_Paul_Henry"}, {"title": "“Cybernetic Serendipity: The Computer and the Arts”, Studio International special issue, ed. Jasia Reichardt, 1968. Contents", "url": "https://studiointernational.com/index.php/cybernetic-serendipity-the-computer-and-the-arts"}, {"title": "Lecture by Elaine O'Hanrahan on Desmond Paul Henry, 24 September 2024. Computer Conservation Society, announcement", "url": "https://computerconservationsociety.org/lectures/2024-25/20240924.htm"}, {"title": "“'Homage to Henry' Analogue Drawing Machine developed and built by Dr. Jack Tait” (2024-426). Science Museum Group Collection", "url": "https://collection.sciencemuseumgroup.org.uk/objects/co8990142/homage-to-henry-analogue-drawing-machine-developed-and-built-by-dr-jack-tait"}],
   "related": {"notes":["cybernetic-serendipity","jean-tinguely-meta-matics","lissajous-figures-harmonograph","zuse-graphomat-z64","calcomp-565"],"editorial":["plotter-art","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/desmond-paul-henry-drawing-machines-henry-estate.jpg", "alt": "A black and white photograph of a dense mechanical device full of gears, dials, rods and cables. On top, three pens in a holder rest on a sheet of paper on which swirling curved lines have been drawn.", "credit": "One of Desmond Paul Henry's drawing machines, built around a bombsight computer, with a drawing in progress. Photo: Desmond Paul Henry estate (uploaded by Elaine O'Hanrahan), Free Art License, via Wikimedia Commons."},
   "text": "Desmond Paul Henry (1921–2004) was a philosopher at Manchester University who, in the 1960s, built three drawing machines out of analogue bombsight computers from the Second World War. They made curving line drawings with real pens, and he showed them in London from 1962.\n\nThe bombsight\n\nA bombsight computer was a calculator carried in Second World War bombers to work out when to release the bombs so that they hit the target. It was analogue, calculating with moving mechanical parts rather than stored numbers. According to Wikipedia, Henry bought his first one, a Sperry model, in 1952 from an army surplus warehouse in Manchester.\n\nHow the machines drew\n\nHenry kept the bombsight's mechanism and attached pens to it. Electric servo motors drove the gears, and the pens hung over a drawing table that stood still or moved. The first machine drew with ballpoint pens, the later ones with Indian ink in technical pens. As the parts turned against each other, the pen traced long loops and overlapping curves.\n\nThe machines could not be programmed, and they stored nothing. What they drew depended on chance in how they were built and run, and Henry said he let each machine \"do its own thing\". JAEV's Plotter art therefore lists Henry among the early computer artists who did not use a pen plotter. A plotter like the Zuse Graphomat Z64 follows coordinates sent by a digital computer; Henry's machines only ever drew what their own mechanism did.\n\nThree machines\n\nThe Science Museum Group dates the three machines to 1961, 1962 and 1967. Henry's first show of machine drawings was at the Reid Gallery in London in 1962. Wikipedia gives its title as Ideographs.\n\nIn 1968 the second machine and its drawings were in Cybernetic Serendipity at the Institute of Contemporary Arts in London, and Henry wrote \"The Henry drawing computer\" for its catalogue.\n\nWhat remains\n\nThe remains of the second machine are with the Science Museum in London, and Manchester's Museum of Science and Industry showed a retrospective of his machine drawings in 2011. His daughter, Elaine O'Hanrahan, looks after the D. P. Henry Archive. Between 2012 and 2019 the artist-engineer Jack Tait built a machine in Wales by working backwards from Henry's; the Science Museum Group now holds it, with the note that it makes similar drawings but \"does not aim to replicate them\"."},
{"type": "note", "title": "Diffusion-limited aggregation (Witten and Sander, 1981)", "url": "https://jaev.gallery/notes/diffusion-limited-aggregation/",
   "description": "Diffusion-limited aggregation: particles wander at random and stick where they touch, growing a branching cluster. Witten and Sander's 1981 model, live.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "diffusion-limited aggregation", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1224521"}], "mentions": [{"name": "Diffusion-Limited Aggregation, a Kinetic Critical Phenomenon", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q27350148"}, {"name": "Paul Bourke", "type": "Person", "sameAs": null}, {"name": "random walk", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q856741"}],
   "sources": [{"title": "T. A. Witten Jr. and L. M. Sander, “Diffusion-Limited Aggregation, a Kinetic Critical Phenomenon”. Physical Review Letters 47 (19), p. 1400, 9 November 1981 (abstract page)", "url": "https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.47.1400"}, {"title": "Thomas C. Halsey, “Diffusion-Limited Aggregation: A Model for Pattern Formation”. Physics Today 53 (11), November 2000, pp. 36–41", "url": "https://aip.brightspotcdn.com/PTO.v53.i11.36_1.online.pdf"}, {"title": "Paul Bourke, “DLA – Diffusion Limited Aggregation”, June 1991, updated 2004 and 2014", "url": "https://paulbourke.net/fractals/dla/"}, {"title": "“Diffusion-limited aggregation”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Diffusion-limited_aggregation"}, {"title": "L. M. Sander, “Diffusion-limited aggregation: a kinetic critical phenomenon?”. Contemporary Physics 41 (4), 2000, pp. 203–218", "url": null}, {"title": "Kevin R Johnson, “DLA Cluster”, 19 May 2006. Wikimedia Commons, CC BY 2.5", "url": "https://commons.wikimedia.org/wiki/File:DLA_Cluster.JPG"}],
   "related": {"notes":["random-walk","game-of-life","boids-craig-reynolds","reaction-diffusion"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/diffusion-limited-aggregation-copper-kevin-r-johnson.jpg", "alt": "Photograph of a copper deposit on a turquoise background, seen from above: from a small electrode in the middle, feathery golden-brown branches grow outwards, each forking again into finer side branches.", "credit": "A copper cluster grown by diffusion-limited aggregation from a copper sulfate solution in an electrodeposition cell. Photo: Kevin R Johnson, 2006, CC BY 2.5, via Wikimedia Commons."},
   "text": "Diffusion-limited aggregation (DLA) is a way for a cluster to grow: particles wander at random, and each one stops for good where it first touches the cluster. The physicists Tom Witten and Len Sander introduced it in 1981 in Physical Review Letters, as a model of \"irreversible colloidal aggregation\", in a paper that begins \"A model for random aggregates is studied by computer simulation.\"\n\nHow it works\n\nThe rule is short. Paul Bourke gives it for a picture made of pixels:\n\nStart with an empty image. One particle is fixed: \"a single black pixel in the center\".\n\nLet a new particle loose at the edge and move it one step at a time, in a random direction each time, so that its path is a random walk.\n\nWhen it comes next to a fixed particle, it sticks. It belongs to the cluster now, and the next particle starts.\n\nNothing tells the cluster to branch. It branches because of where wandering particles arrive. In the physicist Thomas C. Halsey's words, \"an arriving random walker is far more likely to attach to one of the tips of the cluster\" than to get deep into one of its \"fjords\" without touching something first. The tips grow, and in doing so they shield the gaps behind them, at every scale.\n\nThe result is a fractal: the number of particles grows more slowly than the area the cluster covers. In two dimensions and without a grid, its fractal dimension is about 1.71, more than a line (1) and less than a filled surface (2). The same rule also works in three dimensions, as Len Sander points out; his review of 2000 covers the model at length.\n\nNew drawing\nLive sketch by JAEV: on a grid of 241 × 241 cells, particles start on a circle just outside the cluster and step at random up, down, left or right until they land next to a fixed particle. A walker that strays too far is dropped. The drawing stops when the cluster nears the edge, after about 2,500 particles. Code CC BY 4.0.\n\nWhere it appears\n\nThe same branching shows up wherever growth is fed by particles that arrive by diffusion: copper deposited from a solution by an electric current, mineral deposits, fluid pushed into a thin gap between two plates, and the paths of electrical breakdown in an insulator. Bourke adds coral growth and \"the path taken by lightning\".\n\nChanging the rule\n\nSmall changes to the rule change the form. If a particle sticks only with a certain probability, and otherwise walks on, it gets further into the gaps; Bourke finds that the form then becomes \"more hairy and solid\". Computer drawings of this kind were popular as computer art in the 1990s, often under the name Brownian trees. In DLA, as in Conway's Game of Life, only the rule is written; the form is left to evolve. See also Generative Art.\n\nPaul Bourke, whose page on DLA this note draws on, read it in October 2026 and suggested one wording, which we have used."},
{"type": "note", "title": "Digital Harmony (John Whitney, 1980)", "url": "https://jaev.gallery/notes/john-whitney-digital-harmony/",
   "description": "In Digital Harmony (1980) John Whitney described the principle of his computer films: every element moves at a whole-number multiple of one speed. How it works.",
   "datePublished": "2026-10-23", "dateModified": "2026-10-23",
   "author": "JAEV Editorial",
   "about": [{"name": "John Whitney", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q3182739"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "IBM", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q37156"}, {"name": "Permutations", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q122661843"}],
   "sources": [{"title": "William Moritz, “Digital Harmony: The Life of John Whitney, Computer Animation Pioneer”. Animation World Network, 1997", "url": "https://www.awn.com/animationworld/digital-harmony-life-john-whitney-computer-animation-pioneer"}, {"title": "Gene Youngblood, Expanded Cinema. New York: E. P. Dutton, 1970, p. 208 (chapter “Computer Films”)", "url": "https://www.vasulka.org/Kitchen/PDF_ExpandedCinema/book.pdf"}, {"title": "Jim Bumgardner, “Visual Harmony”. KrazyDad blog, 2006, quoting John Whitney, Digital Harmony (1980), p. 38", "url": "https://blog.krazydad.com/2006/04/visual-harmony/"}, {"title": "Bill Alves, “Visual Microtonality”. Microfest", "url": "https://microfest.org/visual-microtonality"}],
   "related": {"notes":["john-whitney-catalog","lissajous-figures-harmonograph","spirograph-hypotrochoid","cybernetic-serendipity"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/john-whitney-digital-harmony-jaev.jpg", "alt": "Three circles side by side, each with forty red dots joined by a thin black line. In the first the dots form a single curling spiral, in the second nested pentagons, in the third nested triangles.", "credit": "Diagram by JAEV of Whitney's principle, not of his films: forty elements, the outer ones turning faster, shown just after the start of a cycle, a fifth of the way round and a third of the way round. CC BY 4.0."},
   "text": "Digital Harmony is a book by the American animator John Whitney (1917–1995), published in 1980. In it he described the principle behind the computer films he had made since the late 1960s: picture and music can be built on the same kind of harmony, with movements in whole-number ratios to each other.\n\nFrom cams to computers\n\nBefore he worked with digital computers, Whitney made films on an analogue machine he had built from a wartime anti-aircraft gun director; that machine and the film Catalog (1961) are described in the note on John Whitney's Catalog. In 1966 IBM took him on as artist in residence, the first major corporation to have one, and until 1969 he worked with the company's digital computers. Jack Citron wrote the programs for the IBM 360.\n\nHis first computer film there was called Homage to Rameau, after the composer whose Treatise on Harmony (1722) had given Whitney his direction. In the films that followed, Permutations (1968), Matrix I–III (1971–72) and Arabesque (1975), he showed what he called \"harmonic progression\". The film historian William Moritz sees the book as the culmination of that work.\n\nThe principle\n\nGive every element of the picture its own speed. \"If one element were set to move at a given rate, the next element might be moved at two times that rate.\" The third moves three times as fast, and so on: the same ratios as the harmonic series in music. Because every speed is a whole-number multiple of the slowest, all the elements line up again each time the slowest has gone round once.\n\nBetween those moments the elements form figures. When the slowest element has gone a fifth of the way round, every fifth element is back in the same direction, and the line through them draws a five-pointed figure; at a third of the way round, a three-pointed one.\n\nNew drawing\nSketch by JAEV of Whitney's principle, not of his films: a row of dots from the centre outwards, joined by a thin line. In each minute the innermost dot goes round once, the next twice, the next three times, and so on. Watch the line fold into stars and spirals and straighten again. The number of dots is chosen at random; the drawing is ours. Code CC BY 4.0.\n\nThe same whole-number ratios make the closed curves in Lissajous figures and the Spirograph. The wider history of art made from rules and systems is in JAEV's Generative Art."},
{"type": "note", "title": "Digitalteatern (Malmö, 1981–1985)", "url": "https://jaev.gallery/notes/digitalteatern-malmo/",
   "description": "Digitalteatern was Charlotte and Sture Johannesson's Apple II computer art studio in Malmö: what it had, how they worked, why it ended.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Digitalteatern", "type": "Thing", "sameAs": null}], "mentions": [{"name": "Charlotte Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4956816"}, {"name": "Sture Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5884840"}, {"name": "Sten Kallin", "type": "Person", "sameAs": null}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}],
   "sources": [{"title": "Charlotte Johannesson. Take Me to Another World. Museo Nacional Centro de Arte Reina Sofía, Madrid, 7 April – 16 August 2021", "url": "https://museoreinasofia.es/en/exhibition/charlotte-johannesson"}, {"title": "Robert Stasinski, “Pixel Pioneer”. Kunstkritikk, 17 May 2021", "url": "https://kunstkritikk.com/pixel-pioneer/"}, {"title": "Sture Johannesson and Ann-Charlotte Johannesson, interviewed by Anna Orrghen, 2 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/4-ann-charlotte-och-sture-johannesson.pdf"}, {"title": "Kunsthalle Wien, archive: Charlotte Johannesson (exhibition Radical Software)", "url": "https://archiv.kunsthallewien.at/en/charlotte-johannesson/"}, {"title": "Charlotte Johannesson. Llévame a otro mundo. Press dossier, Museo Reina Sofía, 2021", "url": "https://recursos.museoreinasofia.es/descargas/Documento/dossier_charlotte_johannesson.pdf"}, {"title": "Sten Kallin, interviewed by Anna Orrghen, 10 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}],
   "related": {"notes":["sture-johannesson","astrid-sampe-computer-textile","ibm-1130-swedish-computer-art","hertz-ink-jet-colour-plotter"],"editorial":["computer-art-in-sweden","the-colour-cubes"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/apple-ii-plus-bilby.jpg", "alt": "A beige Apple II Plus computer with a built-in dark brown keyboard and a rainbow Apple badge, seen at an angle on a white background.", "credit": "An Apple II Plus, the kind of computer Digitalteatern was built on; not one of its machines. Photo: Bilby, CC BY 3.0, via Wikimedia Commons."},
   "text": "Digitalteatern (the Digital Theatre) was a computer studio for art run by the artists Charlotte Johannesson and Sture Johannesson in Malmö. Museums and the art press date it 1981 to 1985. It was built on Apple II computers that the two owned. Most Swedish computer art before it had been made on machines borrowed from companies and universities, as told in Computer Art in Sweden.\n\nThe name and the dates\n\nSture Johannesson explained the name as a joke at the expense of Sweden's free theatre groups: \"We have created a free theatre group, we are free from actors and everything, it is a digital theatre.\"\n\nThe dates differ by source. In the 2007 interview he says it began in 1978–79, \"when we got our first computer, Apple\", and ran until 1985. How that first computer was obtained also differs. Kunsthalle Wien writes that in 1978 Charlotte Johannesson traded a tapestry, I'm NO ANGEL (1972–73), for an Apple II; the Reina Sofía says she travelled to California in 1978 and bought an Apple II Plus. In the interview the couple say the first one was traded, and that their trip to California, where they met Steve Wozniak, was in 1981.\n\nThe equipment\n\nAccording to the interview, the arts council Konstnärsnämnden turned the project down, and the Swedish Board for Technical Development (Styrelsen för teknisk utveckling) and a bank paid for it. Kunstkritikk counts seven Apple computers; Kunsthalle Wien nine computers, with printers, monitors and synthesisers. The Johannessons describe a Corvus hard disk of 20 megabytes, which cost 120,000 kronor and connected the Apples so that work could be moved from one to another; an Alpha Syntauri music system; a Servogor pen plotter; and an early colour printer that \"never really worked well\".\n\nSture Johannesson built and ran the system. Charlotte Johannesson made the pictures, directly on the screen.\n\nFrom loom to pixels\n\nCharlotte Johannesson trained as a weaver in Malmö in the early 1960s. She saw the screen as a fabric: \"when you weave you have a grid, and a square could just as well be a point.\" The screen was 192 pixels high.\n\nPrinting a picture meant translating pixels into pen strokes. The plotter held ink pens, and \"the computer had no idea what colour it was\": the colour was whichever pen they put in. One picture took about sixteen hours, so the plotter ran overnight. If the system failed, the sheet held a single line.\n\nVisitors, television, the end\n\nDigitalteatern had many visitors and much press, but no other artists came to work there. For an advertising agency the Johannessons made a computer-generated sequence that was shown in SVT's notice programme Anslagstavlan. The money ran out in 1985 and the studio was wound up; some of the machines went to the technical museum in Malmö. The Reina Sofía adds that Apple's closed graphical interface, from 1984 on, left Charlotte Johannesson less room to work.\n\nTheir friend Sten Kallin of IBM thought the machines too coarse: \"there was no resolution, only coarse, square dots.\" The pictures came back in 2021, when the Reina Sofía showed about 150 of Charlotte Johannesson's works in Take Me to Another World, among them new weavings made from Digitalteatern images."},
{"type": "note", "title": "EMS, Elektronmusikstudion (Stockholm, 1964)", "url": "https://jaev.gallery/notes/ems-elektronmusikstudion/",
   "description": "EMS, the Electronic Music Studio in Stockholm, opened at Sveriges Radio in 1964 and became a computer-controlled studio. Its machines and its history.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Elektronmusikstudion", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q3672234"}], "mentions": [{"name": "Göran Sundqvist", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19885695"}, {"name": "Knut Wiggen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6240816"}, {"name": "Karl-Birger Blomdahl", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1208405"}, {"name": "Lars-Gunnar Bodin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5580344"}, {"name": "Jan W. Morthenson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1147400"}, {"name": "Sveriges Radio", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1543058"}, {"name": "Fylkingen", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q5511234"}, {"name": "Statens musikverk", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q10677700"}, {"name": "PDP-15", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q40887513"}, {"name": "Buchla 200 series Electric Music Box", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q4982718"}],
   "sources": [{"title": "Jøran Rudi, “Elektronmusikstudion”. Store norske leksikon", "url": "https://snl.no/Elektronmusikstudion"}, {"title": "Om Elektronmusikstudion EMS; Hitta hit; Utrustning i våra studior. Elektronmusikstudion EMS, Stockholm", "url": "https://elektronmusikstudion.se/om-elektronmusikstudion-ems/"}, {"title": "Jøran Rudi, “Unpacking the Musical and Technical Innovation of Knut Wiggen”. Organised Sound 23 (2), 2018, pp. 195–207", "url": "http://www.knut-wiggen.com/Texts/Rudi_OS_23.3.pdf"}, {"title": "Lars-Gunnar Bodin, interviewed by Anna Orrghen, 5 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/26-lars-gunnar-bodin.pdf"}, {"title": "Göran Sundqvist, interviewed by Anna Orrghen, 31 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/5-goran-sundqvist.pdf"}, {"title": "Jan W Morthenson, interviewed by Anna Orrghen, 17 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/6-jan-w-morthenson.pdf"}, {"title": "Elektronmusikstudion – konst, teknik och politik. Scenkonstmuseet, Stockholm", "url": "https://scenkonstmuseet.se/utstallningar/elektronmusikstudion-konst-teknik-och-politik/"}],
   "related": {"notes":["knut-wiggen-musicbox","lars-gunnar-bodin","jan-w-morthenson","datasaab-and-swedish-computer-art","punched-paper-tape"],"editorial":["computer-art-in-sweden"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/ems-buchla-200-tekniska-museet-possan.jpg", "alt": "Close-up of a modular synthesizer: grey aluminium panels with blue and red knobs, four VU meters with needles, rows of sliders, and coloured patch cables plugged into small sockets.", "credit": "The Buchla 200 modular synthesizer from EMS, shown by the studio at Tekniska museet, Stockholm, on 6 November 2010. Photo: possan, CC BY 2.0, via Wikimedia Commons."},
   "text": "EMS (Elektronmusikstudion, the Electronic Music Studio) is Sweden's centre for electroacoustic music and sound art, in Stockholm. It was set up at the national broadcaster Sveriges Radio in 1964, pushed by the radio's head of music, the composer Karl-Birger Blomdahl, and its first director was Knut Wiggen.\n\nA tape studio first\n\nWiggen, who also chaired the music society Fylkingen, had built a small studio at the Workers' Educational Association (ABF) in 1961. EMS opened with a conventional studio for composing on analogue tape, a workspace while the real project was built. It was in Sveriges Radio's old radio-theatre rooms on Kungsgatan, and the tape studio was called Klangverkstaden, \"the sound workshop\".\n\nThe hybrid studio\n\nThe real project was a studio of analogue sound equipment under the control of a computer. Most of it was ready in 1966. The composer played it from a control console about nine metres long, on which every parameter of the equipment was laid out, and switched values on and off by touching the surface with a copper brush. EMS tested a computer at Stockholm University in 1968 and then bought its own, a PDP-15; it arrived in 1970.\n\nThe computer was too slow to calculate control signals while the music played, so they were stored on digital magnetic tape and played back from it. Composers typed their pieces on teleprinters that punched paper tape, in the language EMS-1, written by a team at Uppsala University and finished in spring 1972. James Beauchamp's comparison of synthesis systems in 1973 called EMS \"probably the most powerful system in the world to be placed for the exclusive use of composers on a 24 hour basis\". Jan W. Morthenson found it \"very cumbersome for making a single sound\", because it was a hybrid studio.\n\nComposers against the plan\n\nComposers meanwhile made pieces with what there was. Morthenson brought the sounds for Neutron Star (1967), computed on a power company's Datasaab D21, to EMS and made the piece there. According to Lars-Gunnar Bodin, Wiggen told some of them to stop composing until his system was ready. By the early 1970s EMS had lost its place as Sveriges Radio's major development project. A new board, with several composers on it, wanted less research and more help with composers' immediate needs, and the text-sound composers wanted the money to go to the tape studio. Wiggen resigned in 1975.\n\nAfter Wiggen\n\nBodin tells what followed. A state inquiry of 1977 proposed closing EMS and moving its equipment, the computer included, to the Royal College of Music. Bodin ran the studio unofficially from 1977 and applied for the post in 1979, when the ministry let EMS go on. EMS left Kungsgatan in 1985, by Bodin's account, for purpose-built rooms on Söder Mälarstrand. It is there today, at number 61, as part of the state agency Statens musikverk. Its seven studios are open around the clock all year, to several hundred Swedish and visiting composers and sound artists a year.\n\nHow the computers Swedish composers used in the 1960s were borrowed, mostly from industry, is told in Datasaab and Swedish computer art and Computer Art in Sweden."},
{"type": "note", "title": "Flow fields", "url": "https://jaev.gallery/notes/flow-fields/",
   "description": "A flow field is a grid of angles that curves follow step by step: how the grid is filled, how the curves are kept apart, and where the method comes from.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "vector field", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q186247"}], "mentions": [{"name": "Tyler Hobbs", "type": "Person", "sameAs": null}, {"name": "Perlin noise", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1404167"}],
   "sources": [{"title": "Tyler Hobbs, “Flow Fields”, 3 February 2020", "url": "https://www.tylerxhobbs.com/words/flow-fields"}, {"title": "Bruno Jobard and Wilfrid Lefer, “Creating Evenly-Spaced Streamlines of Arbitrary Density”. 8th Eurographics Workshop on Visualization in Scientific Computing, 1997 (bibliographic record)", "url": "https://isgwww.cs.uni-magdeburg.de/~stefans/npr/entry-Jobard-1997-CES.html"}, {"title": "Tyler Hobbs, “Fidenza”, 11 June 2021", "url": "https://www.tylerxhobbs.com/words/fidenza"}, {"title": "“Tyler Hobbs”. Avant Arte", "url": "https://avantarte.com/insights/articles/tyler-hobbs"}],
   "related": {"notes":["perlin-noise","plotter-path-optimisation","line-hatching"],"editorial":["generative-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/flow-fields-jaev.jpg", "alt": "Hundreds of thin black curves on warm paper, running side by side in swirling bands like the grain in wood, none of them touching. Faint grey ticks between them show the direction stored at each point of the grid.", "credit": "Drawing by JAEV: a 50 × 50 grid of angles from gradient noise (faint ticks) and curves that follow it in short steps, each stopping at the edge, after a set number of steps, or when it comes too close to a curve already drawn. CC BY 4.0."},
   "text": "A flow field is a grid in which every point holds a direction. A curve is drawn by starting somewhere, looking up the direction nearest to it, taking a short step that way and repeating. The method is common in generative art, and the artist Tyler Hobbs describes it step by step in his essay Flow Fields (2020).\n\nThe grid\n\n\"Flow fields are based around a grid,\" Hobbs writes, and at each point of the grid sits an angle. The artist chooses how fine the grid is and how the angles vary across it. If they vary smoothly, curves that follow them bend smoothly too.\n\nThe angles have to come from somewhere. \"About 90% of the time, people use Perlin noise to initialize the vectors,\" Hobbs writes: each noise value is turned into an angle. Perlin noise gives values that change smoothly from point to point, so neighbouring angles stay close. Hobbs also calls it \"so overdone\" and suggests inventing other ways to distort the field.\n\nDrawing the curves\n\nThree choices shape the result.\n\nStep length. Small enough that \"you don't see any sharp points on the curve\".\n\nNumber of steps. \"Short curves may look more like \"fur\". Long curves are more fluid.\"\n\nStarting points. On a regular grid, chosen at random, or placed by circle packing.\n\nKeeping curves apart\n\nWithout a rule against it, curves can run into each other and along each other. Hobbs's rule: \"At each step of a curve, check if any other existing curves are too close, and if so, stop.\" For evenly spaced lines he points to a paper from scientific visualisation, where such curves are called streamlines: Bruno Jobard and Wilfrid Lefer's \"Creating Evenly-Spaced Streamlines of Arbitrary Density\" (1997). The sketch below uses the simple stopping rule.\n\nNew drawing\nLive sketch by JAEV: a 50 × 50 grid of angles from gradient noise (faint ticks, every second point shown) and curves that follow it in steps of 4 units out of 1,000. A curve stops at the edge, after 160 steps, or when it comes within 9 units of a curve already drawn. Code CC BY 4.0.\n\nIn works\n\nHobbs's Fidenza (2021), on Art Blocks, is built on a flow field that he uses to \"produce unpredictable, organic curves\". Hobbs also makes many works with a pen plotter. A flow-field curve is already a chain of short straight steps, which is exactly what a plotter draws (see Plotter Art). A drawing of thousands of curves also gives the pen a long way to travel between them, which is the subject of the note on plotter path optimisation. For the wider field, see the editorial Generative Art."},
{"type": "note", "title": "Floyd–Steinberg dithering (1976)", "url": "https://jaev.gallery/notes/floyd-steinberg-dithering/",
   "description": "How Floyd–Steinberg dithering turns grey into black and white dots by passing each pixel's rounding error to its neighbours: 7, 3, 5 and 1 sixteenths.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Floyd–Steinberg dithering", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1324107"}, {"name": "error diffusion", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q17010900"}], "mentions": [{"name": "Robert W. Floyd", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92641"}, {"name": "dither", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q376493"}, {"name": "halftone", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1110021"}],
   "sources": [{"title": "“Floyd–Steinberg dithering”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Floyd%E2%80%93Steinberg_dithering"}, {"title": "Craig S. Kaplan and Robert Bosch, “TSP Art”. Bridges: Renaissance Banff, 2005, pp. 301–308", "url": "https://archive.bridgesmathart.org/2005/bridges2005-301.html"}, {"title": "Tanner Helland, “Image Dithering: Eleven Algorithms and Source Code”, 28 December 2012", "url": "https://tannerhelland.com/2012/12/28/dithering-eleven-algorithms-source-code.html"}, {"title": "Lisa Adang, “The Aesthetics of the Color Plotter”. Cooper Hewitt, Smithsonian Design Museum, 8 May 2018", "url": "https://www.cooperhewitt.org/2018/05/08/aethetics-of-the-color-plotter/"}],
   "related": {"notes":["color-program-mikael-jern","tsp-art","weighted-voronoi-stippling","hertz-ink-jet-colour-plotter"],"editorial":["generative-art","the-colour-cubes"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/floyd-steinberg-dithering-jaev.jpg", "alt": "Three versions of the same ball, lit from the upper left, made only of black square pixels on warm paper. Left: a solid black crescent where the ball is darker than half grey. Middle: a regular grid pattern of dots that gets denser towards the shadow. Right: scattered dots that get denser towards the shadow, with no visible grid. Small grey labels under each.", "credit": "Diagram by JAEV: one grey picture of a ball, 96 × 96 pixels, turned into black and white three ways: every pixel darker than half grey made black (left); ordered dithering with a 4 × 4 Bayer matrix (middle); Floyd–Steinberg error diffusion (right). CC BY 4.0."},
   "text": "Floyd–Steinberg dithering is a method for turning a grey picture into one made only of black and white dots, by passing the error made at each dot on to the dots next to it. It was published in 1976 by the computer scientists Robert W. Floyd and Louis Steinberg, in a three-page paper titled \"An adaptive algorithm for spatial grey scale\".\n\nThe problem\n\nA newspaper printed in black ink on white paper can only put a dot or leave it out, and so can many printers and the pixels of a black-and-white screen. Showing shades of grey with only two colours is called halftoning; dithering is the kind of halftoning made for a fixed grid of pixels.\n\nThe simplest rule is a threshold: every pixel darker than half grey becomes black, the rest white. All the shading is lost, and a lit ball turns into a black crescent, as in the left of the picture above. Ordered dithering compares the pixels with a fixed pattern of thresholds, such as a 4 × 4 Bayer matrix, so mid-greys become regular grids of dots (middle). In Lund in the 1970s, Mikael Jern's COLOR program for the Hertz ink-jet plotter also worked with fixed patterns, adjusting \"the dot density in a series of 16 steps\". How his colour cubes became prints is told in JAEV's The colour cubes. The drawback of fixed patterns is that the eye sees them, and they distract from the picture.\n\nHow it works\n\nFloyd and Steinberg visit the pixels one at a time, left to right along a row and row by row from the top. For each pixel:\n\nRound it to black or white, whichever is nearer.\n\nWork out the error: how much lighter or darker the pixel was than the value it was given. A pixel at 40 per cent grey that is made white has an error of 40 per cent.\n\nAdd that error, in fixed shares, to four neighbours not yet visited: 7/16 to the pixel on the right, 3/16 to the one below left, 5/16 to the one below and 1/16 to the one below right.\n\nThe shares add up to 16/16, so no grey is lost: what one pixel could not show is shown by the pixels around it. Where the picture is 40 per cent grey, about 40 per cent of the pixels end up black, scattered rather than in a grid (right of the picture). According to Wikipedia, the weights were chosen so that an area of exactly half grey comes out as a checkerboard.\n\nNew drawing\nSketch by JAEV: a random grey picture of 100 × 100 pixels, made black and white with a threshold at half grey (left) and with Floyd–Steinberg error diffusion (right). Code CC BY 4.0.\n\nDots for a pen\n\nFor a plotter, a dithered picture is a list of places to put the pen down. Kaplan and Bosch, who make line drawings from dots, point out that most dithering tries to hide its pattern, while for art the pattern can be the point: they used deliberately ordered dithering to get maze-like TSP art. A method that spaces dots evenly instead of on a grid is weighted Voronoi stippling."},
{"type": "note", "title": "Generative Computergrafik (Stuttgart, 1965)", "url": "https://jaev.gallery/notes/generative-computergrafik-stuttgart-1965/",
   "description": "From 5 to 19 February 1965 Georg Nees showed computer drawings in Stuttgart, one of the first exhibitions of computer art. What was shown and said.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "University of Stuttgart", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q122453"}, {"name": "Siemens", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q81230"}],
   "sources": [{"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal, Spring 2009", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}, {"title": "“Timeline: Events”. DAM Digital Art Museum, Berlin", "url": "https://dam.org/museum/exhibitions_ui/timelines/events/"}, {"title": "“Georg Nees”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Georg_Nees"}, {"title": "Georg Nees, Generative Computergraphik. Doctoral dissertation, 1969, with the 2006 reprint. Internet Archive", "url": "https://archive.org/details/generative_computergraphik"}],
   "related": {"notes":["georg-nees-schotter","zuse-graphomat-z64","tendencies-4-zagreb","frieder-nake-hommage-a-paul-klee"],"editorial":["georg-nees","generative-art","there-should-be-no-computer-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/generative-computergrafik-stuttgart-1965-jaev.jpg", "alt": "A single thin black line on warm paper that zigzags between twenty-three points scattered at random in a square and closes on itself, crossing itself many times.", "credit": "Reconstruction by JAEV after the method of Georg Nees's 23-Ecke, one of the drawings in rot 19: twenty-three points chosen at random and joined by straight lines. Our own points, not the original. CC BY 4.0."},
   "text": "Generative Computergrafik was a small exhibition of drawings by the mathematician Georg Nees, shown in Stuttgart from 5 to 19 February 1965. It is usually counted among the first exhibitions of computer art anywhere, and as the first in Europe.\n\nWhere and what\n\nThe exhibition is listed as shown at the Studiengalerie of the Technische Hochschule Stuttgart, now the University of Stuttgart. In practice that meant the seminar room of the Institute of Philosophy, on the eighth floor of the Hahn-Hochhaus. The institute's director, the philosopher Max Bense, regularly showed concrete and constructivist art and poetry there.\n\nOn the walls were about a dozen drawings: thin black lines, matrices of small figures in variation, overlapping rectangles. Nees worked for Siemens in Erlangen. He wrote the programs in ALGOL 60; a computer calculated the drawing and stored it as instructions on paper tape, and the tape drove a Zuse Graphomat Z64, a precise but slow flatbed drawing machine.\n\nThe booklet\n\nIssue 19 of rot, a series of small square booklets edited by Bense and Elisabeth Walther, was on sale at the opening. It held six of Nees's drawings, among them 23-Ecke (Polygon of 23 vertices) and Andreaskreuz (St Andrew's cross), and a three-page text by Bense, \"Projekte generativer Ästhetik\" (Projects of generative aesthetics). Frieder Nake calls it, in retrospect, the first manifesto of computer art.\n\nThe opening\n\nNake was at the opening on the afternoon of 5 February and wrote down what he remembered in 2009. Many of the artists present were hostile. One asked whether Nees could make his machine draw like an artist. Nees answered: \"Yes, I can. If you can tell me precisely how to define your way of drawing.\" Professors from the Academy of Fine Art left, some slamming doors. Bense tried to calm them: \"what you see here is only artificial art.\" The quotations are Nake's English rendering of a German conversation, from memory.\n\nAfterwards\n\nFrom 5 to 26 November 1965 Nees and Nake showed together at Galerie Wendelin Niedlich in Stuttgart. The DAM timeline counts it as the third public show of art programmed for a digital computer and drawn by a plotter. The exhibitions of that year, in Stuttgart and New York, are described in Generative Art.\n\nNees went on to make Schotter, explained in the note Schotter, and in 1969 wrote a doctoral dissertation called Generative Computergraphik. The longer story is told in Georg Nees; the drawing machine has its own note, Zuse Graphomat Z64. What followed in Zagreb in 1968–69 is in Tendencies 4."},
{"type": "note", "title": "The harmonograph", "url": "https://jaev.gallery/notes/harmonograph/",
   "description": "The harmonograph draws with two pendulums swinging at right angles. Tisley's instrument of the 1870s, how it is tuned, why its lines spiral inwards.",
   "datePublished": "2026-10-23", "dateModified": "2026-10-23",
   "author": "JAEV Editorial",
   "about": [{"name": "harmonograph", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q240559"}], "mentions": [{"name": "Lissajous curve", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q594135"}, {"name": "pendulum", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q20702"}],
   "sources": [{"title": "Joseph Goold, Charles E. Benham, Richard Kerr and L. R. Wilberforce, Harmonic Vibrations and Vibration Figures, ed. Herbert C. Newton. London: Newton & Co., 1909. Internet Archive", "url": "https://archive.org/details/in.ernet.dli.2015.222057"}, {"title": "“Samuel Charles Tisley”. British Map Engravers – A Supplement", "url": "https://britishmapengravers.net/entries/t-entries-2/samuel-charles-tisley/"}, {"title": "Thomas B. Greenslade, Jr., “Harmonographs”. Instruments for Natural Philosophy, Kenyon College", "url": "https://physics.kenyon.edu/EarlyApparatus/Oscillations_and_Waves/Harmonographs/Harmonographs.html"}, {"title": "“Tisley's harmonograph”, accession no. 2033. Whipple Museum of the History of Science, University of Cambridge", "url": "https://collections.whipplemuseum.cam.ac.uk/objects/10336"}, {"title": "“Harmonograph”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Harmonograph"}],
   "related": {"notes":["lissajous-figures-harmonograph","spirograph-hypotrochoid","john-whitney-digital-harmony","desmond-paul-henry-drawing-machines"],"editorial":["plotter-art","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/harmonograph-plate-iv-1909.jpg", "alt": "Two black figures printed on white, one above the other, each made of hundreds of fine curved lines. The upper looks like a flattened figure of eight, the lower like a heart crossed by an X. Below them: Plate IV.", "credit": "Two harmonograph figures in the ratio 3 : 4, at different phases. Plate IV from Harmonic Vibrations and Vibration Figures, ed. Herbert C. Newton (London: Newton & Co., 1909). Public domain, via the Internet Archive."},
   "text": "A harmonograph is a drawing machine driven by pendulums. A handbook published by the London instrument makers Newton & Co. in 1909 defines it as \"an instrument for recording the curves resultant from the compounded movements of two pendulums oscillating at right angles\". One pendulum moves the pen, the other moves the paper, and the line on the paper records both movements at once. The figures are related to the Lissajous figures, but a pendulum slowly comes to rest, so a harmonograph's lines spiral inwards instead of repeating.\n\nBefore the harmonograph\n\nAccording to the handbook, the earliest form was Professor Hugh Blackburn's pendulum, \"first shown in 1844\": a heavy weight on a cord, hung so that it swung in two directions at once, with a pointer that traced its path \"in sand or lampblack\". Around 1870 Hubert Airy noticed that a shoot of an acacia tree, pulled aside and released, moved in a curious orbit as it came to rest. He tied a light pencil to it and recorded the movement on paper, then built a compound pendulum of long jointed rods carrying a weight of 50 pounds. The handbook calls it \"the actual progenitor of Tisley's Harmonograph\".\n\nTisley's instrument\n\nSamuel Charles Tisley (1829–1883) was a London optician and globe maker, and the harmonograph is the instrument he is remembered for; he \"appears to have invented\" it. With George Spiller he made a double-pendulum version for the lecture hall, first described by Tisley in 1873: the pen scraped soot from a plate of smoked glass lying on a projector, so the audience saw a white line drawing itself on a black screen. The 1909 handbook dates the first showing of the harmonograph \"in practically its present form\" to 1874. One of Tisley's instruments was used at the Cavendish Laboratory in Cambridge and is now in the Whipple Museum there.\n\nHow it works\n\nNewton & Co.'s simple harmonograph, Fig. 1 in Harmonic Vibrations and Vibration Figures (1909). Public domain, via the Internet Archive.\n\nIn the simple harmonograph two pendulums hang through a small table on legs. Each is a long rod with a weight that can be clamped higher or lower. One carries the platform with the paper, the other an arm with the pen, and they swing at right angles to each other.\n\nTuning. Moving a weight changes how fast its pendulum swings. The handbook advises finding the right position \"by experiment and not by calculation\".\n\nRatio. If one pendulum swings three times while the other swings four, the figure has three loops along one side and four along the other, as in the plate above.\n\nDamping. The pen should press lightly. Pressing too heavily \"means increased friction, bringing the pendulum to rest sooner\", and the lines lie further apart.\n\nThe ratios have the same names as musical intervals: 2 : 3 is a fifth, 3 : 4 a fourth. The handbook uses the comparison, but warns that it is \"rather misleading to call the harmonograph figures 'music made visible'\".\n\nThe formula\n\nEach pendulum moves like a sine wave that shrinks over time. For one pendulum, x(t) = A sin(ft + p) e, where A is how far it swings, f how fast, p where in its swing it starts, and d how quickly it comes to rest. A full figure adds two such terms in each direction, one for each pendulum. This is how most harmonograph programs work today, and it is the rule behind the drawing in JAEV's film in the note on Lissajous figures. Other machines that draw by combining movements are described in Spirograph and Desmond Paul Henry's drawing machines."},
{"type": "note", "title": "Herbert W. Franke (1927–2022)", "url": "https://jaev.gallery/notes/herbert-w-franke/",
   "description": "Herbert W. Franke (Vienna 1927 – Egling 2022): physicist, writer and computer art pioneer. Oscillograms from 1954, Quadrate, KAES, Ars Electronica.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-22",
   "author": "JAEV Editorial",
   "about": [{"name": "Herbert W. Franke", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q78620"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Ars Electronica", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q678361"}, {"name": "ZKM | Center for Art and Media Karlsruhe", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q191228"}, {"name": "Siemens", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q81230"}],
   "sources": [{"title": "“Herbert W. Franke”. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/9709"}, {"title": "“Herbert W. Franke”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Herbert_W._Franke"}, {"title": "art meets science – Foundation Herbert W. Franke, comments on this note, email to JAEV, 22 October 2026", "url": "https://art-meets-science.io/"}, {"title": "“Art historical classification”. art meets science – Foundation Herbert W. Franke", "url": "https://art-meets-science.io/en/art-historical-classification/"}, {"title": "“Quadrate (Squares – 1968/69)”. art meets science – Foundation Herbert W. Franke", "url": "https://art-meets-science.io/en/quadrate-squares-first-digital-computer-graphics-by-herbert-w-franke-1967-69/"}, {"title": "G. Färber and W. Probst, “Automatische Versuchssteuerung und Versuchsauswertung mit dem IBM System 1130. Dargestellt an einem Beispiel aus der Medizin”. IBM Nachrichten 18 (1968), no. 188, pp. 126–131 (April); offprint sent to JAEV by the foundation", "url": "https://art-meets-science.io/en/quadrate-squares-first-digital-computer-graphics-by-herbert-w-franke-1967-69/"}, {"title": "Herbert W. Franke, KAES 1 (Algebraic Curves), 1969–70. Victoria and Albert Museum, London, E.197-2008 (object record text)", "url": "https://collections.vam.ac.uk/item/O152466/algebraische-kurven-algebraic-curves-print-franke-herbert-w"}, {"title": "“Farbraster (Color Grids)”. art meets science – Foundation Herbert W. Franke", "url": "https://art-meets-science.io/en/herbert-w-franke-color-grids/"}, {"title": "“Rotationen / Projektionen”. art meets science – Foundation Herbert W. Franke", "url": "https://art-meets-science.io/en/series-rotations-projections/"}, {"title": "“Rotation Plate, Fischertechnik and Spirograph (1958–1974)”. art meets science – Foundation Herbert W. Franke", "url": "https://art-meets-science.io/en/herbert-w-franke-rotation-plate-fischertechnik-and-spirograph/"}, {"title": "“Ars Electronica 1979”. Ars Electronica", "url": "https://ars.electronica.art/festival/?p=427"}, {"title": "“Herbert W. Franke / Gottfried Jäger. Art and Construction”. Museum Folkwang, Essen", "url": "https://www.museum-folkwang.de/en/exhibition/herbert-w-franke-gottfried-jager"}, {"title": "“Herbert W. Franke: Donation to Museum Folkwang”. art meets science – Foundation Herbert W. Franke", "url": "https://art-meets-science.io/en/herbert-w-franke-donation-to-museum-folkwang/"}, {"title": "“Edition Herbert W. Franke”. art meets science – Foundation Herbert W. Franke", "url": "https://art-meets-science.io/en/edition-herbert-w-franke-out-soon/"}],
   "related": {"notes":["generative-computergrafik-stuttgart-1965","tendencies-4-zagreb","lissajous-figures-harmonograph","john-whitney-catalog"],"editorial":["generative-art","there-should-be-no-computer-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/herbert-w-franke-mike-krueger.jpg", "alt": "An elderly man with white hair and glasses sits at a pale wooden table in front of a white wall, speaking, with both hands resting on an open book. A microphone and a glass of water stand on the table.", "credit": "Herbert W. Franke at the Penta-Con, 8 September 2007. Photo: Mike Krüger, CC BY-SA 4.0, via Wikimedia Commons."},
   "text": "Herbert W. Franke (1927–2022) was an Austrian physicist and science-fiction writer who made pictures with electronic machines from the mid-1950s, first analogue and from 1969 digital. He also co-founded the festival Ars Electronica in Linz in 1979.\n\nLife\n\nFranke was born in Vienna on 14 May 1927. He studied physics and several other subjects there and took his doctorate in 1950. From 1952 to 1957 he worked in the advertising and press department of Siemens in Erlangen; from 1957 he lived as a freelance writer. He wrote the book Kunst und Konstruktion (Art and Construction, 1957), novels, popular science and books on art and technology. He died in Egling, Bavaria, on 16 July 2022, aged 95.\n\nThe oscillograms\n\nAn oscillograph, or oscilloscope, draws an electrical signal as a moving point of light on a screen. If two oscillating voltages steer the point sideways and up and down at the same time, it traces closed curves, the Lissajous figures also known from pendulum machines.\n\nFranke's first series of such pictures, the Oscillograms, dates from December 1954. The Viennese physicist Franz Raimann built an analogue computing system for him, in close collaboration with Franke. It added, subtracted, multiplied or divided oscillations before they reached the oscillograph, which was the output device and gave the series its name. Franke photographed the screen, and often moved the camera past it while the shutter was open, so that a curve was repeated as \"evenly fanned out lines\".\n\nOn 3 January 1959 an exhibition of these pictures, Experimentelle Ästhetik (Experimental Aesthetics), opened at the Museum of Applied Arts in Vienna. That is six years before the first exhibitions of digital computer drawings, such as Georg Nees's in Stuttgart in February 1965.\n\nDigital work\n\nFranke's first digital computer graphics were the series Quadrate (Squares). A student wrote the program in Fortran in 1968, following Franke's flow diagram, on an IBM 1130 that the Technical University of Munich had built up for the Max Planck Institute of Psychiatry. Squares were placed in three planes, their number, size and position chosen by the computer's pseudo-random generator. The engineer Georg Färber had set up the installation, with an interface for an incremental plotter, for experiments at the institute, and he and Wolfgang Probst described it in IBM Nachrichten in 1968. As a freelance writer Franke always had to look for computers to work with, which is why he used so many different systems. The series KAES followed in 1969, on a Siemens 4004 computer, with a program that Franke conceived and the programmer Peter Henne wrote. The curves were drawn by a plotter and printed as silkscreens, part of a silkscreen series for the 1970 Venice Biennale. In 1971 he published Computergraphik – Computerkunst (Computer Graphics – Computer Art), which the V&A describes as one of the first accounts of the field.\n\nIn the 1970s he often worked on machines in the Siemens research centres in Erlangen and Munich. The Farbraster (Colour Grids) were made with the Sicograph, a device Siemens in Erlangen developed in 1973 for colouring X-ray images. Franke fed it a random pattern instead of an X-ray, transformed it on screen, and had it printed by an early ink-jet plotter that had only red, green and blue, no black. The Rotationen and Projektionen were calculated in real time on an interactive graphics screen at the Siemens research laboratory in Munich, filmed on 16 mm, and in 1974 projected as the set for a dance performance at the Experimentierbühne of the Bavarian State Opera.\n\nFrom the 1970s Franke also built his own drawing machines, among them several plotters made from Fischertechnik, the construction kit, with an electric control for drawing curves from cams.\n\nArs Electronica\n\nThe Ars Electronica festival opened in Linz on 18 September 1979. Its founders were Franke, the electronic musician Hubert Bognermayr, the music producer Ulli A. Rützel and Hannes Leopoldseder of the Austrian broadcaster ORF.\n\nWhere to see the work\n\nFranke gave his archive to the ZKM in Karlsruhe in 2017. The foundation that looks after his work has given around 250 analogue and digital works to the Museum Folkwang in Essen, which shows him together with the photographer Gottfried Jäger in Art and Construction, from 16 October 2026 to 10 January 2027. The foundation is also publishing his books in an Edition Herbert W. Franke, beginning with Kunst und Konstruktion. The early years of computer art in Europe are described in JAEV's Generative Art.\n\nCorrected on 22 October 2026 with information from art meets science – Foundation Herbert W. Franke: the date of the first oscillograms (December 1954), the role of the analogue computer, and Quadrate as Franke's first digital work. The foundation also pointed us to the article by Färber and Probst, the Siemens systems and the Fischertechnik plotters."},
{"type": "note", "title": "The Hertz ink-jet colour plotter (Lund, 1970s)", "url": "https://jaev.gallery/notes/hertz-ink-jet-colour-plotter/",
   "description": "How Hellmuth Hertz's ink-jet plotter at Lund University printed computer images in three inks in the 1970s, and what became of it.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "inkjet printing", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q95474715"}], "mentions": [{"name": "Carl Hellmuth Hertz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q77580"}, {"name": "Mikael Jern", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63869789"}, {"name": "Lund University", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q218506"}, {"name": "Applicon", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q4781517"}, {"name": "UNIVAC 1108", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2467608"}, {"name": "Iris printer", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q6070386"}],
   "sources": [{"title": "Thomas Larsson and Ulf Stenlund, “Vignettes of Sweden's Computer Graphics History”. IEEE Annals of the History of Computing, 2008", "url": "https://www.es.mdu.se/pdf_publications/1105.pdf"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}, {"title": "“Carl Hellmuth Hertz”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Carl_Hellmuth_Hertz"}, {"title": "“Bläckstråleskrivare, prototyp” (TEKS0043360). Tekniska museet, Stockholm, via DigitaltMuseum", "url": "https://digitaltmuseum.org/021026357019"}, {"title": "“Applicon, Inc.”, exhibitor, SIGGRAPH 1979. ACM SIGGRAPH History Archives", "url": "https://history.siggraph.org/?p=185440"}, {"title": "“Iris printer”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Iris_printer"}],
   "related": {"notes":["color-program-mikael-jern","beck-and-jung","ibm-1130-swedish-computer-art"],"editorial":["the-colour-cubes","computer-art-in-sweden","plotter-art"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/hertz-ink-jet-colour-plotter-tekniska-museet.jpg", "alt": "A grey metal machine on a wooden pallet: a long drum lies under a clear plastic cover, with a control panel of green, red, blue and yellow buttons on the right and a blue power supply with orange cables beside it.", "credit": "Prototype ink-jet printer with three jets, made at Lund University in 1976 and used by the Geological Survey of Sweden until 1992. Tekniska museet, Stockholm. Photo: Agnes Andersson, Tekniska museet, CC BY 4.0."},
   "text": "The Hertz colour plotter was an ink-jet printer for computer images, built at Lund University by the physicist Hellmuth Hertz and his laboratory in the early 1970s. It printed pictures as dots of three inks on paper wrapped round a drum, and its programmer counts it among the first colour plotters in the world.\n\nWho built it\n\nHellmuth Hertz (1920–1990) became professor of electrical measurement technology at Lund in 1963. He is also known for the first echocardiographs, made with the physician Inge Edler. According to Tekniska museet, he patented the ink-jet principle in 1965, and the patent was assigned to an American consulting firm that sold licences to printer makers. The plotter itself was run by his technician Boris Smeds.\n\nHow it works\n\nA nozzle shoots a continuous stream of ink droplets, in the programmer Mikael Jern's description about a million a second. An electric signal either lets the stream go straight on to the paper or stops it. Switching the stream on and off places dots. The plotter had three nozzles, for cyan, yellow and magenta; where all three fall on the same spot, the dot is black. The paper was fixed to a rotating drum, and the picture was printed line by line, like a scanner.\n\nThe plotter was not connected to a computer. A picture was calculated on the computing centre's UNIVAC 1108, written to magnetic tape, and the tape was carried to the plotter in the building next door. For an A4 sheet the computer had to hold about 2,000 × 1,200 dots for each of the three colours, on machines with 64–128 KB of memory, so much of the software dealt with keeping only part of the picture in memory at a time. That software is described in the note on COLOR.\n\nThe sources differ on dates and resolution\n\nLarsson and Stenlund's history of Swedish computer graphics says a working prototype was ready by 1970 and gives a resolution of 125 dots per inch. Jern, interviewed in 2007, places the plotter in 1973 and says they worked at 150 dots per inch.\n\nWhat came of it\n\nHertz went on to build two more A4 plotters and, from 1974, a first A1 plotter. Users abroad posted their tapes to Lund, by Jern's count twenty to forty a day. Contracts with Applicon, a CAD company in the Boston area, were signed in 1976, and the first plotters were sold around 1977 for about 100,000 dollars; Larsson and Stenlund give 1977 for the sale. At SIGGRAPH 1979 Applicon showed its Color Plotter: an off-line ink-jet plotter with a tape unit, printing up to 22 × 34 inches at 125 points per inch. In 1984 two former Applicon employees who had worked with Hertz founded Iris Graphics, whose ink-jet printers were later used for fine-art prints.\n\nThe plotter's best-known images are colour cubes, which the artists Beck & Jung turned into prints; the story is told in The colour cubes. Olof Broström's Automatic Colour Cubes at JAEV takes up those cubes again.\n\nWhere to see one\n\nTekniska museet in Stockholm holds a prototype ink-jet printer with three jets, made at Lund University in 1976 and used by the Geological Survey of Sweden in Uppsala until 1992."},
{"type": "note", "title": "The Hilbert curve", "url": "https://jaev.gallery/notes/hilbert-curve/",
   "description": "The Hilbert curve (1891) is one path through every cell of a square grid. How it is built, why near points stay near, and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Hilbert curve", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1366592"}, {"name": "space-filling curve", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q567843"}], "mentions": [{"name": "David Hilbert", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q41585"}, {"name": "Giuseppe Peano", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q191029"}, {"name": "Peano curve", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1725409"}],
   "sources": [{"title": "Brian Hayes, “Crinkly Curves”. American Scientist 101 (2013), Computing Science column", "url": "https://www.americanscientist.org/sites/americanscientist.org/files/2013416124139665-2013-05Hayes.pdf"}, {"title": "David Hilbert, “Über die stetige Abbildung einer Linie auf ein Flächenstück”. Mathematische Annalen 38 (1891), pp. 459–460 (bibliographic record)", "url": "https://doi.org/10.1007/BF01199431"}, {"title": "“Hilbert curve”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Hilbert_curve"}],
   "related": {"notes":["l-systems-lindenmayer","plotter-path-optimisation","tsp-art","floyd-steinberg-dithering"],"editorial":["generative-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/hilbert-curve-jaev.jpg", "alt": "Three squares side by side on warm paper. Each holds one black path with right-angled turns that passes through every cell of a grid: 16 cells, then 64, then 1,024. Under each black path a thin red line shows the path of the order before, with fewer cells.", "credit": "Diagram by JAEV: the Hilbert curve of orders 2, 3 and 5 in black, each over the order before it in red. CC BY 4.0."},
   "text": "The Hilbert curve is a single path that passes through every cell of a square grid, turning only at right angles and never crossing itself. The German mathematician David Hilbert described it in 1891, a year after Giuseppe Peano had defined the first curve that fills a square.\n\nHow it is built\n\nCut the square into four quadrants and join their centres with three lines: up, across, down. That U is the curve of order 1. For order 2, cut each quadrant into four again and put a smaller U in each, turned or mirrored so that the end of one lies next to the start of the next; three short lines join the four copies into one path. Repeat. Brian Hayes, writing in American Scientist, describes it as a program that does not know how to fill a square, but knows that a quarter of a square is also a square, and hands each quarter to itself.\n\nEach order has four times as many cells as the one before: 4, 16, 64. After seven orders the path runs through 4 = 16,384 cells. Every finite order is an ordinary line of straight pieces and corners. Only in the limit, after infinitely many subdivisions, does it reach every point of the square.\n\nNext order\nLive sketch by JAEV: the Hilbert curve, drawn from its start at the lower left, with the order before it in faint lines underneath. It opens at order 3 (64 cells); each click draws the next order, and after order 7 (16,384 cells) it starts again at order 1. Code CC BY 4.0.\n\nPeano, Hilbert and the others\n\nPeano gave no picture. He defined two functions that give the x and y of a point in the square for each position along a line. Hilbert simplified the idea and drew it: his paper in Mathematische Annalen has the first published diagram of such a curve, showing its first three stages. Others followed, among them Wacław Sierpiński's curve of 1912, built on triangles, and a closed variant by the American mathematician E. H. Moore, who in 1900 called these objects \"crinkly curves\".\n\nWhy near stays near\n\nThe useful property is locality: two points close together in the square are usually close together along the curve. Hayes gives an example from Atlanta, where a routing scheme for Meals on Wheels sorted addresses by their position along a Sierpiński curve. On random locations such tours average about 25 per cent longer than the best possible one, found without measuring a single distance. That is the travelling salesman problem, the same one a pen plotter faces when it orders thousands of lines (see plotter path optimisation and TSP art).\n\nThe curve is also used to place dots in halftone and dithering, where following it instead of the rows of the image avoids visible line patterns. For a plotter it has one more quality: any order is one unbranched line, drawn from start to end without lifting the pen. See also Plotter Art and Generative Art.\n\nBrian Hayes, whose “Crinkly Curves” is the first source of this note, read it in October 2026 and had nothing to correct. His own interactive explorations of the curve are at bit-player.org."},
{"type": "note", "title": "Hiroshi Kawano (1925–2012)", "url": "https://jaev.gallery/notes/hiroshi-kawano/",
   "description": "Hiroshi Kawano, a Japanese philosopher of aesthetics, made computer designs from 1964 with Markov chains and painted the printouts by hand. How it worked.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Hiroshi Kawano", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q11479349"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "ZKM | Center for Art and Media Karlsruhe", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q191228"}, {"name": "New Tendencies", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1568501"}],
   "sources": [{"title": "Margit Rosen, “Hiroshi Kawano: Biography”. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/1919"}, {"title": "“川野洋” (Hiroshi Kawano). Wikipedia (Japanese)", "url": "https://ja.wikipedia.org/wiki/%E5%B7%9D%E9%87%8E%E6%B4%8B"}, {"title": "Simone Gristwood, “Hiroshi Kawano (1925–2012): Japan's Pioneer of Computer Arts”. Leonardo 52:1 (2019), 75–80", "url": "https://doi.org/10.1162/LEON_a_01605"}, {"title": "Hiroshi Kawano, KD 28, from the series Artificial Mondrian, 1969. ZKM | Center for Art and Media Karlsruhe (work record, text by Clara Runge)", "url": "https://zkm.de/en/artwork/kd-28"}, {"title": "“Hiroshi Kawano. Der Philosoph am Computer”. ZKM | Center for Art and Media Karlsruhe, 24 September 2011 – 29 January 2012", "url": "https://zkm.de/en/exhibition/2011/09/hiroshi-kawano-der-philosoph-am-computer"}],
   "related": {"notes":["tendencies-4-zagreb","michael-noll-computer-composition-with-lines","computer-technique-group","linear-congruential-generator"],"editorial":["generative-art","there-should-be-no-computer-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/hiroshi-kawano-jaev.jpg", "alt": "A diagram on warm paper. On the left, a small table of numbers such as 0.6, 0.3 and 0.1, with three kinds of square along its edges: empty, filled with black lines and filled with red lines. An arrow points to a large grid on the right where the same three kinds of square follow each other in runs and clusters.", "credit": "Diagram by JAEV of a Markov chain: the table gives the chance of each kind of square following each other kind (left), and the grid is filled square by square with those chances (right). Our own states, numbers and seed, not Kawano's; not a work by Kawano. CC BY 4.0."},
   "text": "Hiroshi Kawano (1925–2012) was a Japanese philosopher of aesthetics who wrote his first computer programs in 1963 and made his first computer-generated designs in 1964. They are counted as the first computer graphics made in Japan with a digital computer. He described his computer art as scientific research rather than artistic activity.\n\nA philosopher at the computer centre\n\nKawano was born to Japanese parents in Fushun, China, on 14 April 1925, and studied philosophy and aesthetics at the University of Tokyo from 1948 to 1951. By 1961 at the latest he had read the Aesthetica of the German philosopher Max Bense and the information theory of Claude Shannon.\n\nIn the autumn of 1963 he taught himself to program, in assembler, for the OKITAC 5090A computer, and in the spring of 1964 he was given time on one at the Computer Center of the University of Tokyo.\n\nMarkov chains\n\nKawano's early designs are based on Markov chains. A Markov chain is a rule for producing a sequence by chance, one in which the probability of the next step depends only on the present one. In a picture, the colour of the square just placed decides how likely each colour is to come next. The probabilities sit in a table, the transition matrix, which has one row for each present colour and one column for each possible next colour, as in the diagram at the top of this page.\n\nFor most of his early works, according to the ZKM, Kawano first analysed a series of images statistically, counting how often and in what position each colour appeared. Random numbers decide each step of a chain; the table decides which steps are likely. How a computer makes such random numbers is explained in the linear congruential generator.\n\nPrintout and paint\n\nThe University of Tokyo's computer centre had only line printers, which print letters and numbers, not pictures. Kawano's printouts held the colour data, not the colours, and the design was then painted by hand, by Kawano and sometimes by his students. The finished works in the ZKM are gouache on paper. JAEV's Plotter Art lists him among the early computer artists who did not use a pen plotter.\n\nIn the series Artificial Mondrian, for example KD 28 of 1969, a transition matrix decided the length of the lines and where they cross, and the colours were assigned at random. Kawano named the series out of admiration for Piet Mondrian, \"without claiming any close visual resemblance\". Compare A. Michael Noll's Computer Composition with Lines.\n\nExhibitions and the archive\n\nKawano took part in the first Japanese computer art contest exhibition in 1968, and in Tendencies 4 in Zagreb in 1968–69. At his first solo exhibition, at Plaza DIC in Tokyo in October 1970, he credited himself with \"planning, programming and text\" and the computer with \"design and works\".\n\nIn 2010 Kawano gave his archive to the ZKM in Karlsruhe, which showed a retrospective, Hiroshi Kawano. Der Philosoph am Computer, from September 2011 to January 2012. He died on 18 December 2012."},
{"type": "note", "title": "Hommage à Paul Klee 13/9/65 Nr. 2 (Frieder Nake, 1965)", "url": "https://jaev.gallery/notes/frieder-nake-hommage-a-paul-klee/",
   "description": "Frieder Nake's Hommage à Paul Klee (1965): bands, vertical lines, triangles and circles chosen by chance. The rules, the machines and a live sketch.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Paul Klee", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q44007"}, {"name": "Highway and Byways", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1589802"}, {"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "Victoria and Albert Museum", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q213322"}],
   "sources": [{"title": "Frieder Nake, Hommage à Paul Klee 13/9/65 Nr. 2, 1965. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/47645"}, {"title": "Frieder Nake, Hommage à Paul Klee, 13/9/65 Nr.2, 1965. Screenprint. Victoria and Albert Museum, London, E.951-2008", "url": "https://collections.vam.ac.uk/item/O211685/"}, {"title": "Frieder Nake, Hommage à Paul Klee 13/9/65 Nr. 2, 1965. Gazelli Art House", "url": "https://gazelliarthouse.com/artworks/8175-frieder-nake-hommage-a-paul-klee-13-9-65-nr.2-1965"}, {"title": "“Hommage à Paul Klee”. DAM Digital Art Museum, Berlin", "url": "https://dam.org/museum/artists_ui/artists/nake-frieder/hommage-a-paul-klee/"}],
   "related": {"notes":["georg-nees-schotter","zuse-graphomat-z64","generative-computergrafik-stuttgart-1965","michael-noll-computer-composition-with-lines"],"editorial":["there-should-be-no-computer-art","plotter-art","georg-nees"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/frieder-nake-hommage-a-paul-klee-jaev.jpg", "alt": "A square of thin black lines on warm paper: bent, roughly horizontal bands stacked from top to bottom. Some cells between the bends hold vertical lines, some narrow triangles, some are empty, and three circles lie on top.", "credit": "Reconstruction by JAEV after the random decisions published for Frieder Nake's Hommage à Paul Klee 13/9/65 Nr. 2: bands that bend without crossing, cells with vertical lines or triangles, a few circles. The counts and probabilities are JAEV's, not the original. CC BY 4.0."},
   "text": "Hommage à Paul Klee 13/9/65 Nr. 2 is a plotter drawing by the mathematician Frieder Nake, dated by its title to 13 September 1965. Nake wrote the program for a Standard Elektrik Lorenz ER56 computer, and a Zuse Graphomat Z64 drew the result with a pen. It is, in the words of one gallery text, one of the drawings most often cited in books and articles about the earliest phase of computer art.\n\nThe painting behind it\n\nThe starting point was Paul Klee's oil painting Hauptweg und Nebenwege (Highway and Byways) from 1929, now in the Museum Ludwig in Cologne.\n\nNake did not try to copy the painting. The Digital Art Museum quotes him: the drawing is \"in no respect the attempt of a simulation\". According to the V&A, he took from Klee the proportions and the balance of vertical and horizontal lines, fixed a framework of horizontals and verticals, and let random variables choose among a set number of options inside it.\n\nHow it works\n\nThe picture is a stack of roughly horizontal bands. The lines between the bands are not straight: they bend at a series of points, the vertices, from the left edge to the right. Between two neighbouring vertices, each band forms a four-sided cell, a quadrilateral. The text on the work published by the Gazelli Art House lists the decisions the program left to chance:\n\nthe width of each band where it starts, at the left edge;\n\nhow each band edge bends from vertex to vertex, with the rule that no edge may cross another;\n\nfor each quadrilateral, whether it stays empty or is filled with vertical lines or with triangles;\n\nhow many lines or triangles go into it, and where;\n\nhow many circles there are, and the position and radius of each.\n\nThe rule against crossing keeps the order of the bands. Everything else may vary. \"A lot of pseudo-random decisions were needed to algorithmically realize this structure\", the same text says.\n\nNo screen showed the result in advance. Nake saw the picture only when the plotter had drawn it.\n\nLive sketch\n\nNew drawing\nSketch by JAEV after the list of random decisions published for Hommage à Paul Klee: bands of random width at the left edge, edges that bend without crossing, cells left empty or given vertical lines or triangles, and a few circles. The number of bands and vertices, the probabilities and the sizes are JAEV's choices; Nake's values are not given in the sources we used. Not the original program and not the work. Code CC BY 4.0.\n\nCopies and prints\n\nThe program could run again, and each run made a new drawing. Nake estimates that the machine drew \"about 30 or 40 copies\" between 1965 and 1967, each counted as an original work. In 1966 he made a screenprint edition of 40. The V&A holds one of the screenprints; the ZKM in Karlsruhe holds the work as well. The machines and dates are compared with other early plotter works in Plotter Art."},
{"type": "note", "title": "HP 7475A plotter (1983)", "url": "https://jaev.gallery/notes/hp-7475a/",
   "description": "The HP 7475A, Hewlett-Packard's six-pen desktop plotter of 1983: how it moves the paper, its speed and unit, its pens, and how to drive it today.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "HP 7475A", "type": "Thing", "sameAs": null}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Hewlett-Packard", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q80978"}, {"name": "HP-GL", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1422842"}, {"name": "vpype", "type": "Thing", "sameAs": null}],
   "sources": [{"title": "HP 7475A Graphics Plotter. HP Computer Museum", "url": "https://www.hpmuseum.net/display_item.php?hw=74"}, {"title": "HP 7475A Interfacing and Programming Manual (07475-90001). Hewlett-Packard, via the Internet Archive", "url": "https://archive.org/details/HP7475AInterfacingandProgrammingManual"}, {"title": "HP 7475A Plotter Operation Manual. Hewlett-Packard, via the Internet Archive", "url": "https://archive.org/details/HP7475AOperationManual"}, {"title": "Roland DXY-990 Operation Manual. Roland DG, via the Internet Archive", "url": "https://archive.org/details/roland-dxy-990"}, {"title": "vpype_config.toml (built-in plotter profiles). vpype, GitHub", "url": "https://github.com/abey79/vpype/blob/master/vpype/vpype_config.toml"}, {"title": "vpype, README. GitHub", "url": "https://github.com/abey79/vpype"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["hp-gl","roland-dxy-plotters","plotter-pens","vpype","axidraw"],"editorial":["plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/hp-7475a-shelby-jueden.jpg", "alt": "A beige desktop machine seen from the front. A sheet of white paper with a plotted graph of a wave lies across it under a smoked plastic cover with a metal rail and the pen carriage. A wire paper support sticks out in front, and a panel of small buttons sits on the right.", "credit": "An HP 7475A with a plotted graph. Photo: Shelby Jueden, CC BY-SA 4.0, via Wikimedia Commons."},
   "text": "The HP 7475A is a desktop pen plotter that Hewlett-Packard introduced in 1983 at $1,895. It holds six pens in a carousel and draws on sheets up to A3. The HP Computer Museum calls it \"the most popular pen plotter ever made\". HP kept it in its range until 1994.\n\nHow it moves\n\nIn the 7475A the paper moves as well as the pen: grit-covered wheels drive the sheet back and forth in one direction while the pen travels across it in the other. HP called this paper-moving technology; the 7475A took it over from the 7470A.\n\nThe pen accelerates at about 2 g and moves at up to 38.1 cm a second. HP gives an addressable resolution of 0.025 mm and a repeatability of 0.10 mm for any given pen. The same manuals define the plotter unit, the smallest move the machine can make, more exactly as 0.02488 mm, about 40.2 units to the millimetre.\n\nWhat it is told\n\nThe plotter was sold with one of two connections, RS-232-C (option 001) or HP's own HP-IB (option 002). Both take the same commands, HP-GL: two letters and some numbers, such as PU to lift the pen and PD to put it down and draw. Other makers built plotters that understood it too: the manual of Roland's DXY-990 advertises compatibility with the HP-GL of the HP 7470 and 7475. See the note on Roland's DXY plotters.\n\nPens\n\nThe carousel takes three kinds of pen: disposable fibre-tip pens for paper, fibre-tip pens for overhead transparency film, and short-body refillable drafting pens with tungsten carbide points, which HP says give the best lines but need refilling and cleaning. The carousel for drafting pens came in 1985. The note on plotter pens follows the pen from these cartridges to today's fineliners.\n\nTwo details\n\nIn 1984 the 7475A was the most profitable single product HP made, helped by the IBM PC and the spreadsheet Lotus 1-2-3, which brought business charts to ordinary computer users. The museum records two oddities. The plotter's built-in lettering drew the figure 8 with a flat top, which only some customers in Japan noticed and HP never corrected. And in 1985 HP replaced the paper stop with a painted white line, as a precaution during a lawsuit with its competitor Houston Instruments, which HP then won.\n\nUsing one today\n\nThe command-line tool vpype has a built-in profile for the 7475A. It uses the 0.02488 mm unit and knows the six pens. An SVG drawing becomes a file the plotter can read with vpype read input.svg layout --fit-to-margins 2cm --landscape a4 write --device hp7475a output.hpgl.\n\nOlof Broström's Unverified Air at JAEV is stored as files for a pen plotter, one drawing a day, in black, red and blue ink. The machines before the 7475A are in JAEV's text on plotter art."},
{"type": "note", "title": "HP-GL, the language of pen plotters", "url": "https://jaev.gallery/notes/hp-gl/",
   "description": "HP-GL, Hewlett-Packard's plotter language from 1977: what IN, SP, PU and PD mean, how big a plotter unit is, and how to make HP-GL today.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "HP-GL", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1422842"}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Hewlett-Packard", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q80978"}, {"name": "vpype", "type": "Thing", "sameAs": null}],
   "sources": [{"title": "HP 9872A Graphics Plotter. HP Computer Museum", "url": "https://www.hpmuseum.net/display_item.php?hw=79"}, {"title": "“HPGL commands”. Reference, PIC microcontroller archive (Hallikainen)", "url": "https://pic.hallikainen.org/techref/language/hpgl/commands.htm"}, {"title": "Inkscape bug report 548918, quoting HP manuals (7475A Interfacing and Programming Manual; HP-GL Programmer's Reference Manual, 1984; HP-GL/2 and HP RTL Reference Guide, 1996)", "url": "https://bugs.launchpad.net/bugs/548918"}, {"title": "HP 7470A Graphics Plotter. HP Computer Museum", "url": "https://hpmuseum.net/display_item.php?hw=73"}, {"title": "HP 7475A Graphics Plotter. HP Computer Museum", "url": "https://www.hpmuseum.net/display_item.php?hw=74"}, {"title": "“Cookbook”. vpype documentation", "url": "https://vpype.readthedocs.io/en/latest/cookbook.html"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["calcomp-565","benson-plotter","zuse-graphomat-z64","plotter-path-optimisation","line-hatching"],"editorial":["plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/hp-gl-jaev.jpg", "alt": "On the left five lines of code in a monospace font: IN; SP1; PU0,0; PD4000,0,4000,4000,0,4000,0,0; PU;. On the right the square it draws, with its corners labelled 0,0, 4000,0, 4000,4000 and 0,4000, small red arrows showing the order of the sides, and a scale line reading 4,000 units = 10 cm.", "credit": "Diagram by JAEV: the program from this note and the square it draws, 4,000 plotter units or 10 cm a side. Red arrows show the order of the sides. CC BY 4.0."},
   "text": "HP-GL (Hewlett-Packard Graphics Language) is the set of commands Hewlett-Packard's pen plotters understand: two letters, then numbers, sent to the plotter as plain text. HP began marketing its two-letter language under that name in 1977, with the 9872A plotter.\n\nA short program\n\nIN;\nSP1;\nPU0,0;\nPD4000,0,4000,4000,0,4000,0,0;\nPU;\n\nIN initialises the plotter. SP1 selects pen 1. PU (pen up) lifts the pen and moves it to the point given, here 0,0. PD (pen down) lowers the pen and draws to each pair of numbers in turn, so this one command draws four connected lines: a square. The last PU lifts the pen again. Each command ends with a semicolon or a line break, and the numbers must be separated by commas, not spaces.\n\nThe numbers are plotter units. One unit is 0.025 mm, the smallest move the plotter can make, so 40 units make a millimetre and the square above is 10 cm across.\n\nPA (plot absolute) measures the coordinates that come after it from the plotter's origin, as above; PR (plot relative) measures them from where the pen is.\n\nNew drawing\nA short HP-GL program, written at random, and what a plotter would draw from it. The line being drawn is shown in bold. Solid: pen down. Dashed: pen lifted and moved. The square is 4,000 units, 10 cm on paper. Simulation by JAEV, not a plotter driver and not output from a real machine. Code CC BY 4.0.\n\nThe plotters\n\nThe 9872A cost $4,200 in 1977. It held four pens; the 9872C of 1981 held eight.\n\nThe 7470A of 1982 was smaller and cost $1,550. Earlier plotters held the paper still and moved the pen over it on a mechanical arm; the 7470A moved the paper instead. The HP Computer Museum calls it the world's first small-format paper-moving plotter. It held two pens and drew on A4.\n\nThe 7475A followed in 1983 at $1,895. It had a carousel of six pens and took A4 and A3. In 1984, helped by the IBM PC and Lotus 1-2-3, it was the most profitable single product HP made. The HP Computer Museum calls it \"the most popular pen plotter ever made\"; it was not discontinued until 1994.\n\nHP-GL today\n\nThe command-line tool vpype can turn an SVG into HP-GL for vintage plotters, for example with vpype read input.svg write --device hp7475a output.hpgl. It has to be told the plotter and the paper size, because, as its documentation says, HP-GL coordinate systems \"vary widely from plotter to plotter and even for different physical paper format\".\n\nOlof Broström's Unverified Air at JAEV is stored as files for a pen plotter, in black, red and blue ink. The machines that came before HP-GL, and the artists who used them, are described in the notes on the CalComp 565 and the Zuse Graphomat Z64 and in JAEV's text on plotter art."},
{"type": "note", "title": "Hummingbird (Charles Csuri, 1967–68)", "url": "https://jaev.gallery/notes/charles-csuri-hummingbird/",
   "description": "Hummingbird is Charles Csuri's computer-animated film in which a drawing of a bird is broken up, scattered and put back. How it was made, and where it is.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Charles Csuri", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5076580"}, {"name": "computer animation", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1401416"}], "mentions": [{"name": "Ohio State University", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q309331"}, {"name": "Museum of Modern Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q188740"}, {"name": "Cybernetic Serendipity", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5197816"}],
   "sources": [{"title": "“Technology + Art: Charles Csuri”. Computer History Museum, Mountain View, exhibit", "url": "https://computerhistory.org/exhibits/technology-art/"}, {"title": "Charles A. Csuri, Hummingbird (fragmentation animation), C07.13169. The Charles A. Csuri Project, Ohio State University", "url": "https://csuriproject.osu.edu/index.php/Detail/objects/775"}, {"title": "“Charles Csuri”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Charles_Csuri"}, {"title": "Charles Csuri, Sine Curve Man Three, 1967. The Charles A. Csuri Project, Ohio State University", "url": "https://csuriproject.osu.edu/Detail/objects/603"}, {"title": "“Cybernetic Serendipity: The Computer and the Arts”, Studio International special issue, ed. Jasia Reichardt, 1968. Contents", "url": "https://studiointernational.com/index.php/cybernetic-serendipity-the-computer-and-the-arts"}, {"title": "Computer Technique Group, Running Cola is Africa, 1967. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/artwork/running-cola-is-africa"}],
   "related": {"notes":["calcomp-565","cybernetic-serendipity","knowlton-harmon-studies-in-perception","computer-technique-group","john-whitney-catalog"],"editorial":["plotter-art","the-rule-is-the-work"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/charles-csuri-hummingbird-jaev.jpg", "alt": "A strip of six film frames drawn in thin grey lines, with sprocket holes along both edges. In the first and last frame a closed black outline; in the frames between, the outline is broken into short straight pieces that drift apart and turn, most scattered in the fourth frame, then come together again.", "credit": "Diagram by JAEV of the method: a line drawing broken into short straight elements, which are moved apart and turned frame by frame and then put back. An abstract outline of JAEV's own, not a bird and not Csuri's drawing. CC BY 4.0."},
   "text": "Hummingbird is a short computer-animated film by Charles Csuri, made at Ohio State University in 1967–68. A line drawing of a hummingbird in flight is broken up, scattered across the screen and put together again. The Museum of Modern Art in New York bought it for its collection, as one of the first works of computer animation.\n\nCsuri\n\nCsuri (1922–2022) played American football for Ohio State and fought in the Second World War, where he was awarded the Bronze Star at the Battle of the Bulge. He came back to study art, took his MA and joined the university's art department. Around 1963 he saw a portrait of a woman produced by a computer, made by the graduate student Juris Raudseps, and began working with the university's computing experts. By 1964 he was making computer pictures. His Sine Curve Man drawings of 1967 were drawn by a CalComp 565 drum plotter. JAEV's Plotter Art counts him among the pioneers of the plotter drawing.\n\nHow the film was made\n\nThe film starts with a drawing made by hand and digitised: turned into coordinates that a program can work with. According to the Csuri Project at Ohio State, he produced more than 14,000 frames, which \"exploded the bird, scattered it about, and reconstructed it\", and the frames were put on 16 mm film. The diagram above shows the principle with an outline of JAEV's own: the same pieces, pushed further apart frame by frame, then brought back.\n\nThe Computer History Museum describes a method like that of the computer films made at Bell Labs, with Fortran programs running on the university's IBM 7094 computer and the frames output on a CalComp 835 microfilm plotter. The Csuri Project's record names a different machine: an IBM 1130, with punched cards. The date differs too, 1967 or 1968, depending on the source. Wikipedia names James Shaffer as Csuri's collaborator on the film.\n\nShown and collected\n\nThe Csuri Project records an award for the film at the fourth International Experimental Film Competition in Brussels, and it dates the Museum of Modern Art's purchase to 1968. In the same year Csuri was in Cybernetic Serendipity in London. The catalogue printed an interview with him.\n\nThe Csuri Project calls these films \"fragmentation animations\", and it sees in them a forerunner of morphing, where one form changes smoothly into another. In Tokyo, in the same years, the Computer Technique Group had a computer turn a running man into a bottle of cola, then into the outline of Africa."},
{"type": "note", "title": "Hypotrochoids: the maths behind Spirograph", "url": "https://jaev.gallery/notes/spirograph-hypotrochoid/",
   "description": "A Spirograph draws hypotrochoids: a wheel rolling inside a ring. The formula, why the tooth counts decide the number of points, and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "hypotrochoid", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1047694"}, {"name": "spirograph", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1485203"}], "mentions": [{"name": "Denys Fisher", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1190034"}],
   "sources": [{"title": "“Spirograph”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Spirograph"}, {"title": "Ashleigh Ratcliffe and Jenny Power, “On the cover: Spirographs”. Chalkdust, 8 November 2024", "url": "https://chalkdustmagazine.com/regulars/on-the-cover/on-the-cover-spirographs/"}, {"title": "“Denys Fisher”, obituary. The Times, 26 October 2002 (transcribed by the Doctor Who Cuttings Archive)", "url": "https://cuttingsarchive.org/index.php/Denys_Fisher_obituary"}],
   "related": {"notes":["lissajous-figures-harmonograph","desmond-paul-henry-drawing-machines","l-systems-lindenmayer","truchet-tiles"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/spirograph-hypotrochoid-palitoy-set-multicherry.jpg", "alt": "A Spirograph set in its red plastic tray, seen from above: two large transparent yellow rings with teeth inside and out, two toothed bars, eighteen round toothed wheels of different sizes full of small pen holes, and four ballpoint pens.", "credit": "Spirograph set made by Palitoy, bought in the UK in the early 1980s. Photo: Multicherry, CC BY-SA 3.0, via Wikimedia Commons."},
   "text": "A hypotrochoid is the curve drawn by a point on a disc that rolls around the inside of a fixed circle. It is the curve of the Spirograph, the drawing toy in which a toothed plastic wheel with a pen in one of its holes is rolled round the inside of a toothed ring. The British engineer Denys Fisher made the first prototype from Meccano parts, and the toy went on sale in Leeds in March 1965.\n\nThe toy\n\nAccording to his obituary in The Times, Fisher \"spent the Christmas of 1962 building, with his family, various drawing machines from Meccano pieces\", and made his prototype \"from a Meccano cog and a geared ring\". Fisher then reached an agreement with the toy company Kenner, and the obituary puts total sales at more than 100 million sets in 85 countries.\n\nThe curve\n\nLet R be the radius of the ring, r the radius of the wheel, and d the distance from the wheel's centre to the pen. As the wheel's centre goes round the ring by an angle t, the pen is at\n\nx = (R − r) cos t + d cos((R − r)/r · t)\ny = (R − r) sin t − d sin((R − r)/r · t)\n\nIn each line, the first part is the wheel's centre travelling round the ring, and the second is the pen turning about that centre as the wheel rolls. If the pen sits exactly on the rim of the wheel, the curve has sharp points and is called a hypocycloid.\n\nCounting the teeth\n\nBecause the parts have teeth, the radii are in the same proportion as the numbers of teeth, and those numbers are printed on the parts. With N teeth on the ring and n on the wheel, the drawing closes after LCM(n, N) / N trips round the ring and has LCM(n, N) / n points, where LCM is the least common multiple. A wheel of 60 teeth in a ring of 96: the least common multiple is 480, so the pen goes round the ring 5 times and the figure has 8 points. Where the pen sits, d, changes the shape of the loops but not their number.\n\nNew drawing\nLive sketch by JAEV: a hypotrochoid drawn from the formula above. Each new drawing picks a ring (96, 105, 144 or 150 teeth, JAEV's choice, not the toy's parts list), a wheel of 24 to 84 teeth and a pen distance at random, and draws until the curve closes. Below, the number of trips round the ring and of points, from the least common multiple. Code CC BY 4.0.\n\nA machine for repetition\n\nA Spirograph drawing is made by one rule repeated exactly, with a single number deciding the whole result before the pen moves. Other drawing machines worked with pendulums instead of gears, see Lissajous figures and the harmonograph. For rules that make images, see Generative art."},
{"type": "note", "title": "The IBM 1130 and Swedish computer art", "url": "https://jaev.gallery/notes/ibm-1130-swedish-computer-art/",
   "description": "A spare IBM 1130 and its drum plotter in Solna made Sweden's first plotter art: Sten Kallin with Astrid Sampe and Sture Johannesson, c. 1970–75.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "IBM 1130", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q3146513"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Astrid Sampe", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q430667"}, {"name": "Sture Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5884840"}, {"name": "Göran Sundqvist", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19885695"}, {"name": "Mikael Jern", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63869789"}, {"name": "Beck & Jung", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q10427586"}, {"name": "UNIVAC 1108", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2467608"}],
   "sources": [{"title": "“IBM 1130”. Wikipedia", "url": "https://en.wikipedia.org/wiki/IBM_1130"}, {"title": "Sten Kallin, interviewed by Anna Orrghen, 10 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "Anna Orrghen, Från matematikmaskin till IT. Fokusgrupp: Media. Slutrapport. Tekniska museet, Stockholm, 2008", "url": "https://www.tekniskamuseet.se/app/uploads/2016/11/slutrapport-media-anna-orrghen.pdf"}, {"title": "“Bresenham line drawing and the IBM 1627”. IBM 1401 restoration project", "url": "https://ibm-1401.info/BresenhamLineDraw.html"}, {"title": "Astrid Sampe with computer programmer Sten Kallin and IBM Plotter 1627, Computer Colonne, 1975. The Art Institute of Chicago, gift of Astrid Sampe", "url": "https://www.artic.edu/artworks/107812/computer-colonne"}, {"title": "“Sture Johannesson: In Memery”, 16 March–25 May 2013. Index – The Swedish Contemporary Art Foundation, Stockholm", "url": "https://indexfoundation.se/exhibitions/sture-johannesson-in-memery"}, {"title": "Elisabeth Fagerstedt, “Beck & Jung: datakonstens pionjärer”, Uppsala konstmuseum 2009, published 2012", "url": "http://elisabethfagerstedtkonsttext.blogspot.com/2012/05/beck-jung-holger-backstrom-1939-1997.html"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}, {"title": "Sture Johannesson and Ann-Charlotte Johannesson, interviewed by Anna Orrghen, 2 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/4-ann-charlotte-och-sture-johannesson.pdf"}],
   "related": {"notes":["calcomp-565","astrid-sampe-computer-textile","sture-johannesson","hertz-ink-jet-colour-plotter","beck-and-jung"],"editorial":["computer-art-in-sweden","plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/ibm-1130-tnmoc-badgerscp.jpg", "alt": "An IBM 1130 system in a museum: a grey card reader on blue cabinets on the left, and on the right the central unit, a white desk with a panel of indicator lights, a keyboard and a blue cabinet.", "credit": "An IBM 1130 at The National Museum of Computing, Bletchley Park. Photo: BadgersCP, CC0, via Wikimedia Commons."},
   "text": "The IBM 1130 was a small scientific computer that IBM introduced in February 1965 for schools and engineering firms. In Sweden one spare 1130, with a drum plotter, became the machine on which the IBM programmer Sten Kallin made pictures with the textile designer Astrid Sampe and the artist Sture Johannesson in the late 1960s and early 1970s.\n\nThe machine\n\nThe 1130 was a 16-bit computer. A drum plotter, the IBM 1627, could be attached. The 1627 Model 1 was a CalComp 565 sold under IBM's name. For a programmer, Kallin explains, the pen could take one step in one of eight directions, along the axes or diagonally, \"and nothing else\".\n\nA computer in a cupboard\n\nOne of the 1130s at IBM's head office was left over and placed in the training department in Solna, where it stood in a small room driving the printers. In the daytime it was busy. In the evenings and at weekends Kallin could use it with a plotter he heard was \"left over somewhere\". He wrote practice programs for it in FORTRAN.\n\nAstrid Sampe. Asked for a picture for a Red Cross auction, Sampe called IBM and was put through to Kallin. He wrote a program that drew the cross many times, smaller and turned each time, with a menu where she typed the number of turns, the angle and the reduction. The pen sat loosely in its holder, so the diagonal lines came out slightly uneven, which Kallin liked. The weaving firm Almedahls printed the cross as curtain fabric; the Art Institute of Chicago credits Computer Colonne (1975) to \"Astrid Sampe with computer programmer Sten Kallin and IBM Plotter 1627\".\n\nSture Johannesson. Johannesson had an \"alphabet\" of three signs, a keyhole, a heart and the two laid over each other, and asked IBM for help to vary it. With Kallin at the 1130 he made INTRA, curves repeated and shifted until moiré appeared; IBM printed some as Christmas greetings to its staff three years running. Orrghen dates INTRA 1969–1974; the 2013 exhibition at Index in Stockholm dated their printouts 1970–1975, made on a CalComp drum plotter with a 30 cm paper roll, fed by punched cards into an 1130 without a screen.\n\nOther machines Swedish artists borrowed\n\nThe 1130 was one borrowed machine among several. Göran Sundqvist programmed Jan W. Morthenson's Neutron Star (1967) on a SAAB D21 belonging to the power company Skandinaviska Elverk. Beck & Jung worked with IBM in Malmö and got their image alphabet out on a line printer. At Lund University the colour plotter was fed by the computing centre's UNIVAC 1108. Machines of their own came later: Sture and Ann-Charlotte Johannesson got their first Apple in 1978–79, the start of Digitalteatern in Malmö. The full story is in Computer Art in Sweden, and the machines in Plotter Art, which ends with Olof Broström's Unverified Air, drawn for a pen plotter today."},
{"type": "note", "title": "Interruptions (Vera Molnár, 1968–69)", "url": "https://jaev.gallery/notes/vera-molnar-interruptions/",
   "description": "Vera Molnár's Interruptions: a grid of short lines, each turned at random, with areas left empty. What the rule does, with a live sketch by JAEV.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Vera Molnár", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1658002"}, {"name": "generative art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1502032"}], "mentions": [{"name": "Victoria and Albert Museum", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q213322"}],
   "sources": [{"title": "Vera Molnár, Interruptions, 1969. Plotter drawing. Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O1193775/"}, {"title": "“Vera Molnar”. DAM Digital Art Museum", "url": "https://dam.org/museum/artists_ui/artists/molnar-vera/"}, {"title": "“Vera Molnar”. Infinite Images, Toledo Museum of Art", "url": "https://infiniteimages.toledomuseum.org/?p=811"}, {"title": "“Vera Molnár, Pioneer of Computer Art, Dies at 99”. The New York Times, December 2023, as reproduced by Galerie Thaddaeus Ropac", "url": "https://ropac.net/news/1609-vera-molnar-pioneer-of-computer-art-dies-at-experimenting-with-algorithms-she-began-to-employ-the/"}, {"title": "Stéphanie Pioda, “Vera Molnár, aux sources du code”. Centre Pompidou, Paris, 2023", "url": "https://www.centrepompidou.fr/en/pompidou-plus/magazine/article/vera-molnar-aux-sources-du-code"}],
   "related": {"notes":["georg-nees-schotter","michael-noll-computer-composition-with-lines","benson-plotter","frieder-nake-hommage-a-paul-klee"],"editorial":["vera-molnar","generative-art","plotter-art"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/vera-molnar-interruptions-diagram-jaev.jpg", "alt": "A diagram in three squares with short labels. 1: a grid of 25 by 25 short lines, all at the same angle. 2: the same lines, each turned in a random direction. 3: the turned lines with some round areas left empty, marked by dashed red circles.", "credit": "Diagram by JAEV of the method described for Vera Molnár's Interruptions: a grid of lines of equal length, each turned at random, then areas left out. The round shape of the empty areas is JAEV's guess. Not an image of her work. CC BY 4.0."},
   "text": "Interruptions is a series of plotter drawings that Vera Molnár made in Paris in 1968–69, among her first works made with a computer. Each sheet is a field of short straight lines turned in every direction, with patches where the lines are missing. The Victoria and Albert Museum holds one, dated 1969, 328 × 347 mm.\n\nHow it works\n\nThe rule has two steps.\n\nA grid of turned lines. Start with a square grid, 25 by 25, and put a straight line of the same length at each point. Turn every line by a random angle. When the lines are about as long as the spacing, neighbours touch and cross, and the field reads as a texture rather than as separate marks.\n\nInterruptions. Choose areas at random and leave the lines there out. The museum descriptions call them \"random interruptions\" and \"voids\".\n\nThe first step makes an even, restless surface. The second breaks it, so the eye has somewhere to stop.\n\nThe V&A adds the point that makes it a series: with each new sheet she altered the algorithm slightly, building on the one before. The sheets are not repeats of one program with new random numbers. They are steps in a search.\n\nNone of the sources we used gives her exact rule for where the empty areas fall or how many there are, so the sketch below makes its own choice.\n\nLive sketch\n\nNew drawing\nSketch by JAEV after the published description of Interruptions: 25 × 25 lines of equal length, each turned at random, with areas left out. The empty areas here are a few round patches of random size plus single missing lines, which is JAEV's guess, not Molnár's rule. Not an image of her work. Code CC BY 4.0.\n\nThe machine and the wait\n\nIn 1968 Molnár taught herself the programming language FORTRAN; she also used BASIC. She entered her programs on punch cards and, according to The New York Times, waited several days for each result to come back drawn by a plotter. The Toledo Museum of Art describes a sheet from 1968 as black ink on Benson plotter paper. With 625 places in the grid, a sheet like this holds several hundred separate lines, each drawn by the pen of a plotter such as the Benson.\n\nThe sources do not agree on where she worked. The Centre Pompidou says that in 1968 she gained access, in complete secrecy, to the computing centre at Orsay; the Digital Art Museum names the experimental psychology laboratory at the Sorbonne. Dates differ in the same way: the V&A dates its sheet 1969, Toledo shows one dated 1968.\n\nWorking through the variants of a rule one sheet at a time is also how Automatic Colour Cubes by Olof Broström at JAEV proceeds: one cube a day until all 122 of Sol LeWitt's incomplete open cubes have been drawn."},
{"type": "note", "title": "Jan W. Morthenson (1940–2024)", "url": "https://jaev.gallery/notes/jan-w-morthenson/",
   "description": "Jan W. Morthenson, Swedish composer, made Neutron Star (1967) on a power company's computer. What the program did and how the piece was made.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Jan W. Morthenson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1147400"}], "mentions": [{"name": "Göran Sundqvist", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19885695"}, {"name": "Lars-Gunnar Bodin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5580344"}, {"name": "Fylkingen", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q5511234"}, {"name": "Elektronmusikstudion", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q3672234"}],
   "sources": [{"title": "Jan W Morthenson, interviewed by Anna Orrghen, 17 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/6-jan-w-morthenson.pdf"}, {"title": "“Jan W. Morthenson”. Wikipedia (Swedish)", "url": "https://sv.wikipedia.org/wiki/Jan_W._Morthenson"}, {"title": "“Jan W. Morthenson”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Jan_W._Morthenson"}, {"title": "Göran Sundqvist, interviewed by Anna Orrghen, 31 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/5-goran-sundqvist.pdf"}, {"title": "Lars-Gunnar Bodin, interviewed by Anna Orrghen, 5 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/26-lars-gunnar-bodin.pdf"}],
   "related": {"notes":["lars-gunnar-bodin","knut-wiggen-musicbox","ibm-1130-swedish-computer-art"],"editorial":["computer-art-in-sweden"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/jan-w-morthenson-jaev.jpg", "alt": "Thousands of short square-wave strokes in black ink: sparse and scattered on the left, growing denser towards the right, where they close into a compact dark body.", "credit": "Reconstruction by JAEV after Morthenson's and Sundqvist's descriptions of Neutron Star (1967): square-wave pulses at random pitches, sparse at first, then denser until they form one body. Not a score or recording of the work. CC BY 4.0."},
   "text": "Jan W. Morthenson (1940–2024) was a Swedish composer and writer on music. His Neutron Star (1967), made with the engineer Göran Sundqvist on a computer that ran hydroelectric dams, is one of the first pieces of Swedish music produced by a computer.\n\nNon-figurative music\n\nMorthenson was born in Örnsköldsvik and studied composition with Ingvar Lidholm and aesthetics in Uppsala. From 1962 he wrote what he called non-figurative music: standing fields of sound that change very slowly, written to remove every \"demagogic\" expression from music, in his word. His book Non-figurative Musik came out in 1966 with a preface by the German theorist Heinz-Klaus Metzger, his teacher.\n\nNeutron Star, 1967\n\nIn 1967 the Society of Swedish Composers turned fifty and commissioned works for a record. For his piece Morthenson worked with Göran Sundqvist on a Datasaab D21 owned by the power company Skandinaviska Elverk. Its everyday job was to regulate the gates of dams in central and northern Sweden according to how much electricity was being used.\n\nSundqvist describes the program as simple. He wrote it in assembler: a random generator and a short loop that played for a set time, one voice at a time. Morthenson wanted short pulses of sound in different frequency ranges and asked for them to sound dry; Sundqvist told him they sounded wet, \"like splashing\". Morthenson took the material to the Elektronmusikstudion (EMS) in Stockholm and mixed it into the piece there.\n\nEach tone stands for an atom or an electron. The piece starts with single, sparse tones and grows denser until the sound forms a compact body, like the pressure in a neutron star. The hard sounds are square waves. Only the computer plays; Morthenson says an orchestra could not reach that density. Lars-Gunnar Bodin, who used it in his teaching, calls it the first work of art music made directly by a computer.\n\nNeither composer could program, Bodin says; the computer work depended on Sundqvist.\n\nPictures on an oscilloscope\n\nSundqvist also made pictures for Morthenson's television work for Westdeutscher Rundfunk in Cologne, among them Supersonics (1969). Morthenson drew a storyboard; Sundqvist produced the images on an oscilloscope, and they were filmed off the screen. Most of the pictures in the programme were analogue studio images. In Morthenson's words: \"sound does not take much computing power, not nearly as much as images\". The same imbalance is one reason why computer music came before computer pictures in Sweden, as told in Computer Art in Sweden.\n\nLater\n\nMorthenson sat on the board of EMS from 1973 to 1975 and chaired Fylkingen in 1975–76. He kept using the density of Neutron Star in orchestral music, writing registers and playing instructions instead of single notes so that musicians could produce masses of tones as fast as possible."},
{"type": "note", "title": "L-systems (Aristid Lindenmayer, 1968)", "url": "https://jaev.gallery/notes/l-systems-lindenmayer/",
   "description": "L-systems rewrite every letter of a string at once. Aristid Lindenmayer's 1968 idea, how a turtle turns the string into a plant, and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "L-system", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1151098"}], "mentions": [{"name": "Aristid Lindenmayer", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q491734"}, {"name": "Przemysław Prusinkiewicz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q93061"}, {"name": "The Algorithmic Beauty of Plants", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q7713097"}, {"name": "turtle graphics", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1501371"}],
   "sources": [{"title": "Przemysław Prusinkiewicz and Aristid Lindenmayer, The Algorithmic Beauty of Plants. Springer-Verlag, 1990; electronic version, front matter. Algorithmic Botany, University of Calgary", "url": "http://algorithmicbotany.org/papers/abop/abop-fm.pdf"}, {"title": "The Algorithmic Beauty of Plants, chapter 1, “Graphical modeling using L-systems”", "url": "http://algorithmicbotany.org/papers/abop/abop-ch1.pdf"}, {"title": "The Algorithmic Beauty of Plants, back matter (bibliography)", "url": "http://algorithmicbotany.org/papers/abop/abop-bm.pdf"}],
   "related": {"notes":["truchet-tiles","spirograph-hypotrochoid","reaction-diffusion","hilbert-curve"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/l-systems-lindenmayer-jaev.jpg", "alt": "Five thin line drawings side by side on warm paper, all the same height. The first is a single red vertical line; each next one has more branches, until the fifth is a fine plant-like stem with many small twigs. In every drawing the main stem is red and the branches black.", "credit": "Diagram by JAEV: the L-system F → F[+F]F[−F]F at 25.7° (Prusinkiewicz and Lindenmayer, 1990, Fig. 1.24a), the axiom and the first four rewriting steps, each scaled to the same height. Red: the main stem. CC BY 4.0."},
   "text": "An L-system is a set of rules for rewriting a string of letters, in which every letter is replaced at the same time. The biologist Aristid Lindenmayer (1925–1989) introduced them in 1968 to describe how simple many-celled organisms grow. Read as drawing instructions, the same strings make branching plants, and the book The Algorithmic Beauty of Plants (1990), written with the computer scientist Przemysław Prusinkiewicz, showed in detail how to draw plants with them by computer.\n\nRewriting in parallel\n\nLindenmayer published the idea in the Journal of Theoretical Biology in 1968 as \"Mathematical models for cellular interaction in development\". Rewriting rules were already in use: from the late 1950s Noam Chomsky's grammars described sentences by replacing symbols, but one at a time. In an L-system the rules \"are applied in parallel and simultaneously replace all letters in a given word\". The reason is biological: the rules stand for cell divisions in an organism \"where many divisions may occur at the same time\".\n\nThe book's smallest example has two rules, a → ab and b → a, and starts from b:\n\nb\n\na\n\nab\n\naba\n\nabaab\n\nabaababa\n\nThe turtle\n\nTo get a picture, the string is read by a \"turtle\", an imaginary pen with a position and a heading, borrowed from the LOGO programming language. The letter F means draw one step forward; + and − mean turn left or right by a fixed angle. Two more symbols make branches: [ stores the turtle's position and heading, and ] returns to the last one stored, so a branch can be drawn and the turtle can go back to where it left the stem.\n\nThe image at the top uses one rule from the book: start with F, replace every F by F[+F]F[−F]F, and turn by 25.7 degrees. After one step there is a stem with two branches; after each further step every segment becomes a small copy of that shape.\n\nChance\n\nA deterministic L-system draws the same plant every time. The book also describes stochastic L-systems, in which a letter has several possible rules and one of them is picked at random each time the letter is rewritten. In its example F has three rules, each with a probability of about one third: F[+F]F[−F]F, F[+F]F and F[−F]F. The results, the authors write, \"look like different specimens of the same (albeit fictitious) plant species\".\n\nNew drawing\nLive sketch by JAEV: three plants from the stochastic L-system in The Algorithmic Beauty of Plants (section 1.7), five rewriting steps each, drawn by a turtle turning 25.7° (the angle is JAEV's choice). Every new drawing rewrites them with new random choices. Not a figure from the book. Code CC BY 4.0.\n\nBeyond plants\n\nThe same method draws curves that are not plants at all. The book shows the Koch snowflake and other fractal curves as L-systems, and lists among later uses space-filling curves and the kolam patterns, an art form from southern India. As with Truchet tiles, a few fixed rules decide the whole image. See also Generative art."},
{"type": "note", "title": "Lars-Gunnar Bodin (1935–2021)", "url": "https://jaev.gallery/notes/lars-gunnar-bodin/",
   "description": "Lars-Gunnar Bodin, Swedish composer and intermedia artist, made one of the first computer-planned pictures in Sweden in 1968. How he worked.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Lars-Gunnar Bodin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5580344"}], "mentions": [{"name": "Göran Sundqvist", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19885695"}, {"name": "Jan W. Morthenson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1147400"}, {"name": "Fylkingen", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q5511234"}, {"name": "Elektronmusikstudion", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q3672234"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}],
   "sources": [{"title": "“Lars-Gunnar Bodin”. Wikipedia (Swedish)", "url": "https://sv.wikipedia.org/wiki/Lars-Gunnar_Bodin"}, {"title": "Lars-Gunnar Bodin, interviewed by Anna Orrghen, 5 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/26-lars-gunnar-bodin.pdf"}, {"title": "Lars-Gunnar Bodin, Curriculum Vitae – bild, 2009", "url": "https://semicolon.se/documents_se/Curriculum%20Vitae-bild(2009).pdf"}, {"title": "Göran Sundqvist, interviewed by Anna Orrghen, 31 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/5-goran-sundqvist.pdf"}, {"title": "“Lars-Gunnar Bodin”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Lars-Gunnar_Bodin"}],
   "related": {"notes":["jan-w-morthenson","knut-wiggen-musicbox","beck-and-jung","ibm-1130-swedish-computer-art"],"editorial":["computer-art-in-sweden","the-colour-cubes"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/lars-gunnar-bodin-jaev.jpg", "alt": "A grid of 10 by 13 square cells on warm paper. Each cell holds between none and fifteen small yellow and orange squares on a four-by-four pattern; some cells are nearly full, some empty.", "credit": "Reconstruction by JAEV after Lars-Gunnar Bodin's account of his 1968 cell method: 130 cells, 0 to 15 elements each from random numbers, yellow or orange. Not the original, which was destroyed. CC BY 4.0."},
   "text": "Lars-Gunnar Bodin (1935–2021) was a Swedish composer and intermedia artist, and one of the first artists in Sweden to plan a picture with a computer. He was born in Stockholm and died in Gnesta. He called himself a komponist, not a tonsättare: someone who composes in any material, sound, text or picture, by placing things according to rules.\n\nBefore the computer\n\nBodin started going to concerts at Fylkingen, the Stockholm society for new music, in 1954, and studied composition privately until 1960. His debut exhibition, at Sturegalleriet in Stockholm in December 1960, showed \"serial structures in picture and music\"; in 1962 he showed \"stochastic structures\" at Galleri Petra. Serial music works with fixed series and rules for changing them; stochastic methods add chance within set limits. Both were in his pictures before any computer was.\n\nLund, 1968: the computer decides where\n\nThe engineer Göran Sundqvist gave Bodin access to a computer. For En festival kring konst och teknologi (A festival around art and technology) in Lund in 1968, the programme lists Bodin's \"serial and stochastic structures\", made with Sundqvist.\n\nThe picture was made of 120 or 130 small cells. He gave rules for each kind of cell and said how many elements of each colour, yellow or orange, there should be. The computer placed them and returned a printout of letters and coordinates. Bodin then painted the picture by hand, cell by cell. The large Lund picture was later destroyed by water in storage. The method, and a reconstruction by JAEV, are described in Computer Art in Sweden.\n\nComputer time was the obstacle. Bodin remembers that renting it would have cost about 1,200 kronor an hour; Sundqvist did the work on the side, at night.\n\nSound, text and the studio\n\nWith the poet Bengt Emil Johnson, Bodin coined the Swedish term text-ljud-komposition (text-sound composition), and from 1967 the two ran festivals of it in Stockholm. He chaired Fylkingen from 1969 to 1972. His largest work, Clouds (1976), used five film projectors, ten slide projectors, three dancers, three singers and eight-channel sound; its prologue, about ten minutes long, is made with frequency-modulated digital sound, which he produced at Dartmouth College because no Swedish computer available to him could do it. He ran the Elektronmusikstudion (EMS) in Stockholm, first unofficially from 1977 and as director from 1979.\n\nPlotter pictures, 1979\n\nAt the end of the 1970s Bodin and Sundqvist made pictures on a plotter that held one technical pen at a time, so they could choose the colour of each line. They were shown in L'Artiste et l'Ordinateur, curated by Torsten Ridell, which opened in Paris and toured; silkscreen versions were issued in two boxes. According to Bodin, he and Sundqvist were the only Swedes in it. His CV lists the tour as Paris, Caen, Lille and Seclin in 1979, Lund and Norrköping in 1980, and Wege der Computerkunst in Kiel in 1981. It also states that Moderna Museet holds two of his works.\n\nLund comes back in Olof Broström's Automatic Colour Cubes at JAEV, which starts from another computer picture made there in the 1970s, told in The colour cubes."},
{"type": "note", "title": "Line hatching for pen plotters", "url": "https://jaev.gallery/notes/line-hatching/",
   "description": "A pen plotter cannot paint a surface. How a program fills a shape with parallel lines, how spacing and crossing give tone, and in what order the lines go.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "hatching", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2734755"}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Inkscape", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q8041"}, {"name": "vpype", "type": "Thing", "sameAs": null}],
   "sources": [{"title": "“Hatching”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Hatching"}, {"title": "Brian Schmalz, “EiBotBoard” (the controller of the EggBot and AxiDraw)", "url": "https://www.schmalzhaus.com/EBB/"}, {"title": "“Hatch fill”. Evil Mad Scientist wiki", "url": "https://wiki.evilmadscientist.com/Hatch_fill"}, {"title": "Drawingbots, hatched (library and vpype plug-in)", "url": "https://github.com/plottertools/hatched"}, {"title": "Antoine Beyeler, vpype", "url": "https://github.com/abey79/vpype"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["plotter-path-optimisation","hp-gl","flow-fields"],"editorial":["plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/line-hatching-jaev.jpg", "alt": "Four irregular shapes with jagged, inward-bending outlines in a row on warm paper, each filled with thin black parallel lines: the first with widely spaced lines, the second with close lines, the third crossed at right angles, the fourth crossed and close, so that the shapes go from light to dark.", "credit": "Diagram by JAEV: four shapes filled by the scan-line method in this note, from light to dark: wide spacing, close spacing, crossed, crossed and close. CC BY 4.0."},
   "text": "Hatching is the drawing and engraving technique of making tone with closely spaced parallel lines; when a second set of lines is laid at an angle to the first, it is called cross-hatching. For a pen plotter it is not a choice of style but the only way to make an area dark.\n\nWhy a plotter needs it\n\nInstead of an image, a plotter is sent moves: lower the pen, go in a straight line to a point, lift the pen. A filled square in a drawing program becomes, for the plotter, only its outline, unless a program first turns the inside into lines. The editorial Plotter Art describes the whole chain, and the note on HP-GL the commands themselves.\n\nHow a fill is computed\n\nThe sketch below uses the scan-line method, in three steps:\n\nTurn the outline so that the hatch direction becomes horizontal.\n\nCut it with horizontal lines, one for every step of the chosen spacing. For each line, find where it crosses the edges of the outline and sort the crossings from left to right. The pen is down between the first and second crossing, up between the second and third, down between the third and fourth, and so on. This even-odd rule also works for shapes that bend inwards or have holes.\n\nTurn the pieces back by the same angle.\n\nCross-hatching is the same fill run a second time at another angle, here 90 degrees.\n\nSpacing, pen and tone\n\nTwo numbers set the tone: the width of the pen line and the distance between lines. Evil Mad Scientist's guide to its Hatch Fill extension for Inkscape says that the choice of spacing \"will depend upon the thickness of the pen\". As arithmetic, ignoring ink that spreads into the paper: a 0.3 mm line every 1 mm covers 30 per cent of the paper. A second set at the same spacing across it leaves 70 per cent of 70 per cent uncovered, so the cover rises to 51 per cent.\n\nNew drawing\nLive sketch by JAEV: four random shapes filled by the scan-line method, from light to dark: wide spacing, close spacing, crossed, and crossed with closer spacing. The angle is random for each shape, and every other line runs the opposite way. Code CC BY 4.0.\n\nThe order of the lines\n\nIf every line were drawn from left to right, the pen would travel back across the shape in the air after each one. Drawing every other line in the opposite direction, as the sketch does, removes most of that. Evil Mad Scientist's extension goes a step further: by default it \"connects the ends of the hatch lines to make long wiggling paths that plot very efficiently\". Sorting the lines of a whole drawing is the subject of the note on plotter path optimisation.\n\nHatching a photograph\n\nThe tool hatched, a plug-in for the plotter program vpype, turns an image into hatching. It divides the picture into black, dark, light and white zones at three brightness thresholds and fills each zone with a different density of lines, diagonal or circular.\n\nAt JAEV\n\nIn Olof Broström's Unverified Air, hatching carries data: nitrogen dioxide is drawn as red lines over the ground between the houses and ozone as blue lines over the roofs, \"the lines growing closer as the values rise\"."},
{"type": "note", "title": "The linear congruential generator", "url": "https://jaev.gallery/notes/linear-congruential-generator/",
   "description": "Multiply, add, keep the remainder: how a linear congruential generator makes random-looking numbers, why it repeats, and the one Georg Nees drew with.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "linear congruential generator", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1190228"}, {"name": "Lehmer random number generator", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q114856"}], "mentions": [{"name": "D. H. Lehmer", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1200338"}, {"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "pseudorandom number generator", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1623338"}, {"name": "Processing", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1053535"}],
   "sources": [{"title": "“Linear congruential generator”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Linear_congruential_generator"}, {"title": "“Lehmer random number generator”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Lehmer_random_number_generator"}, {"title": "Zellyn Hunter, “Schotter – Georg Nees – Part 2”, 2024", "url": "https://zellyn.com/2024/06/schotter-2/"}, {"title": "“Class Random”. Java Platform SE 8 API documentation, Oracle", "url": "https://docs.oracle.com/javase/8/docs/api/java/util/Random.html"}, {"title": "PApplet.java, Processing 4 source code. GitHub", "url": "https://github.com/processing/processing4/blob/main/core/src/processing/core/PApplet.java"}, {"title": "“Content”, JAEV. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/content/"}],
   "related": {"notes":["georg-nees-schotter","sha-256-as-random-source","ten-print-maze","processing"],"editorial":["georg-nees","generative-art"],"exhibitions":["content"]},
   "image": {"url": "https://jaev.gallery/assets/notes/linear-congruential-generator-jaev.jpg", "alt": "Left: a circle with 128 tick marks, criss-crossed by red straight lines that join the numbers of a sequence one after the other; only every fourth tick is long. Right: a square in which 300 black dots lie on five parallel slanting lines. Small grey labels under each.", "credit": "Diagram by JAEV: Georg Nees's rule “multiply by 5, keep the remainder”. Left: with remainder after 128, starting from 1, the red lines join each number to the next; after 32 numbers the sequence is back at 1. Right: with Nees's full 2³¹, each dot is a number and the next one (300 pairs, JAEV's seed); all fall on five lines. CC BY 4.0."},
   "text": "A linear congruential generator is a simple, long-used way for a computer to produce numbers that look random. It takes a number, multiplies it by a constant and adds another constant, then divides by a third and keeps only the remainder. That remainder is the next number, and the rule is applied to it again. The mathematician D. H. Lehmer described the form without addition in a paper given in 1949 and printed in 1951; W. E. Thomson and A. Rotenberg published the form with addition in 1958.\n\nHow it works\n\nWritten as a formula: next = (a × x + c) mod m, where the first x is the seed. Every number lies between 0 and m − 1. Dividing by m turns it into a fraction between 0 and 1, which a program can scale to any range it needs.\n\nThe computer-art pioneer Georg Nees used the simplest version. His dissertation calls the method \"extremely simple\": multiply by 5 and keep the remainder after dividing by 2³¹. The same generator decided the shifts and turns of the squares in his Schotter. To explain it, Nees used a small version that keeps the remainder after 128, which repeats after 32 numbers. Started from 1, it gives 1, 5, 25, 125, 113, 53 and so on; the left half of the picture above draws that loop.\n\nWhy it repeats\n\nThere are only m possible remainders, so sooner or later a number comes back and the sequence repeats. With an added constant and well-chosen values, a generator can run through all m numbers before that happens. Nees called a generator with a short period \"almost always unsuitable\" for his work; the period, he wrote, must be so long that \"we do not notice it\".\n\nNew drawing\nSketch by JAEV: a small generator, next = a × x mod m, with m 128, 256 or 512 and a random multiplier and seed. Left: the numbers as a clock, each line joining a number to the next until the sequence returns to its seed. Right: each dot is a number and the one after it; the dots line up instead of filling the square evenly. Code CC BY 4.0.\n\nThe pattern inside\n\nThe numbers are not independent. If each number and the next are drawn as a point, the points fall on a limited number of straight lines, and in three dimensions on planes. With the multiplier 5 the reason is plain: the next number is 5x minus 0, 1, 2, 3 or 4 times the modulus, so every pair lies on one of five lines (right half of the picture).\n\nThe structure is always there: for any constants, the points lie on at most a certain number of planes, so choosing the constants is a matter of making that number large. These generators must not be used where secrecy matters, as in cryptography.\n\nStill in use\n\nJava's standard class java.util.Random uses \"a linear congruential formula\" on a 48-bit number. Processing, the language many generative artists learned on, gets its random() from that class, so a sketch that calls randomSeed() is in effect setting the seed of a linear congruential generator.\n\nJAEV's exhibition Content takes its chance from a hash instead: it turns a text into a long number, so that \"the same text always gives the same work\"; see the note on SHA-256 as a source of chance."},
{"type": "note", "title": "Lissajous figures and the harmonograph", "url": "https://jaev.gallery/notes/lissajous-figures-harmonograph/",
   "description": "Lissajous figures are the curves of two swings at right angles. Lissajous's tuning forks of 1857, the drawing machines and pendulums, and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Lissajous curve", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q594135"}, {"name": "harmonograph", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q240559"}], "mentions": [{"name": "Jules Antoine Lissajous", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q385440"}, {"name": "Nathaniel Bowditch", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1356911"}, {"name": "Edward Charles Pickering", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q156896"}, {"name": "Hugh Blackburn", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5930039"}, {"name": "Ben F. Laposky", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4885618"}],
   "sources": [{"title": "Edward C. Pickering, “Description of a machine for drawing the curves of Lissajous”. Journal of the Franklin Institute, offprint, Philadelphia 1869. Internet Archive", "url": "https://archive.org/details/descriptionofmac00pick"}, {"title": "J. J. O'Connor and E. F. Robertson, “Jules Antoine Lissajous”. MacTutor History of Mathematics, University of St Andrews", "url": "https://mathshistory.st-andrews.ac.uk/Biographies/Lissajous.html"}, {"title": "“Harmonograph”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Harmonograph"}, {"title": "“Lissajous curve”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Lissajous_curve"}, {"title": "“Blackburn pendulum”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Blackburn_pendulum"}, {"title": "S. Denisov and A. V. Ponomarev, “Oscillons: an encounter with dynamical chaos in 1953?”. Chaos 21, 023123 (2011); arXiv:1007.4790", "url": "https://arxiv.org/abs/1007.4790"}],
   "related": {"notes":["harmonograph","spirograph-hypotrochoid","desmond-paul-henry-drawing-machines","jean-tinguely-meta-matics","perlin-noise"],"editorial":["generative-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/lissajous-figures-pickering-1869-plate.jpg", "alt": "An engraved plate from 1869. At the top, three squares filled with crossing curves, from an open lattice of loops to a dense mesh. Below, a drawing of a wooden machine: an upright board with paper, a vertical pen holder on rods, and a belt running over two wheels at the back. Small drawings of glass pens and a layout of tuning forks, lens and screen at the bottom.", "credit": "Plate I from Edward C. Pickering, “Description of a machine for drawing the curves of Lissajous”, Journal of the Franklin Institute (Philadelphia, 1869): curves drawn by the machine (II–IV) and the machine (I). Boston Public Library, via the Internet Archive. Public domain."},
   "text": "A Lissajous figure is the curve traced by a point that swings in two directions at right angles at the same time. It is named after the French physicist Jules Antoine Lissajous (1822–1880), who studied such curves in 1857 with light reflected from two tuning forks. Nathaniel Bowditch had already produced them in 1815 with a pendulum. A harmonograph is a machine that draws curves of this kind with pendulums.\n\nLissajous's tuning forks\n\nEdward C. Pickering of the Institute of Technology in Boston described the experiment in 1869: \"Mirrors are attached to the prongs of two tuning forks, whose planes of vibration are at right angles to one another.\" A ray of light falls on the first mirror, then the second, and a lens projects it onto a screen. One fork alone moves the spot of light along a horizontal line, the other along a vertical line. \"When both vibrate at the same time, various curves are produced, dependent on the relative pitch of the two forks.\"\n\nThe curve\n\nWritten as a formula, the point is at x = A sin(at + δ), y = B sin(bt) at time t. A and B are the widths of the two swings, a and b their frequencies, and δ the difference in phase, how far one swing is ahead of the other. When a and b are in a ratio of whole numbers, the curve closes on itself; when they are not, it never quite repeats.\n\nNew drawing\nLive sketch by JAEV. The drawings alternate. First a Lissajous figure, x = sin(at + δ), y = sin(bt), with a random whole-number ratio and phase. Then a harmonograph-like curve near the same ratio: each swing shrinks a little as time passes, and one frequency is slightly out of tune, so the curve spirals inwards instead of closing. Not a simulation of any particular machine. Code CC BY 4.0.\n\nDrawing machines\n\nPickering wanted the curves on paper, large enough to show a lecture audience, since \"their geometrical construction is somewhat laborious\". His machine has two wheels joined by a belt. A crank on one wheel moves the paper to and fro horizontally; a crank on the other moves the pen up and down. The ratio of the wheel diameters sets the ratio of the frequencies, and sliding the belt on a wheel changes the phase. His specimens show the ratios 5:8 (a minor sixth), 15:16 (a semitone) and about 44:59, which \"does not close exactly, since the ratio is incommensurable\".\n\nPendulums do the same thing without gears. In the Blackburn pendulum, described by Hugh Blackburn in 1844, a weight hangs from a string that itself hangs from a V-shaped pair of strings, and its path resembles a Lissajous curve. The word harmonograph is found from the 1870s for drawing machines of this kind. In a lateral harmonograph two pendulums move a pen relative to the paper. A swinging pendulum slowly loses energy, so each swing is a little smaller than the one before, and the drawing spirals inwards.\n\nOn a screen\n\nAn oscilloscope in X-Y mode draws a Lissajous figure from two electrical signals, and engineers use it to see how far one signal is ahead of the other, for example the left and right channels of a stereo recording. In the 1950s Ben F. Laposky, a draftsman by profession, built circuits that drew patterns on the screen of an oscilloscope, photographed them and called them oscillons. Fifty-six of them were shown at the Sanford Museum in Cherokee, Iowa, in 1953. See also Generative art."},
{"type": "note", "title": "Méta-Matics (Jean Tinguely, 1959)", "url": "https://jaev.gallery/notes/jean-tinguely-meta-matics/",
   "description": "Jean Tinguely's Méta-Matics (1959) were motor-driven machines that made abstract drawings for visitors. How they worked, and how they differ from plotters.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Métamatic", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q17068976"}, {"name": "Jean Tinguely", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q163938"}], "mentions": [{"name": "Moderna Museet", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1274511"}, {"name": "Museum Tinguely", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q180904"}],
   "sources": [{"title": "“Métamatic”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/M%C3%A9tamatic"}, {"title": "“Jean Tinguely”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Jean_Tinguely"}, {"title": "Jean Tinguely, Méta-Matic nr 17, 1959. Moderna Museet, Stockholm, NMSK 1895", "url": "https://sis.modernamuseet.se/en/objects/details/4591"}, {"title": "Museum Tinguely, “Biografie / Credits”, collection presentation 2023", "url": "https://www.tinguely.ch/de/ausstellungen/ausstellungen/2023/sammlungspraesentation/biografie-credits.html"}, {"title": "Museum Tinguely, “Paris” (Tinguely history)", "url": "https://www.tinguely.ch/en/ahoy/mt-ahoy/tinguely-history/paris.html"}, {"title": "“Metamatic Reloaded”. Museum Tinguely, Basel, 23 October 2013 – 26 January 2014", "url": "https://www.tinguely.ch/en/exhibitions/earlier-exhibitions/2013.html"}],
   "related": {"notes":["desmond-paul-henry-drawing-machines","john-whitney-catalog","rorelse-i-konsten-1961","zuse-graphomat-z64"],"editorial":["generative-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/jean-tinguely-meta-matics-jaev.jpg", "alt": "A line diagram on warm paper: a small motor pulley drives two wheels by belts. A crank pin on each wheel holds a rod, and the two rods meet at a pen above a rectangle of paper, where a red tangle of looping lines has been drawn.", "credit": "Diagram by JAEV of the general principle of a motor-driven drawing machine: a motor, two wheels turning at different speeds, two rods holding a pen, and the line it draws (red). Not the mechanism of any Méta-Matic and not an image of one. CC BY 4.0."},
   "text": "The Méta-Matics are drawing machines by the Swiss sculptor Jean Tinguely (1925–1991), first shown in Paris in 1959. A motor drives an arm that holds drawing tools chosen by the visitor against a sheet of paper, and the machine produces an abstract drawing of lines and dots. They were exhibited six years before the first computer drawings, and Wikipedia counts them among generative works of art.\n\nHow a Méta-Matic draws\n\nA Méta-Matic has neither program nor memory. The result is, in Wikipedia's words, \"a random composition of lines and dots\". The visitor has a share in it by choosing the drawing tools and their colours. The diagram above is JAEV's general picture of such a mechanism, not a drawing of Tinguely's.\n\nThe drawings resemble the gestural abstract painting of the 1950s; they also mimic it. The Moderna Museet in Stockholm describes Tinguely as \"aiming a blow at informal painting, which was all the rave in Paris in the 1950s\".\n\nParis, 1959\n\nIn 1959, half a year after a joint show with Yves Klein, the gallery owner Iris Clert showed les Méta-Matics de Tinguely: les sculptures qui peignent (\"the sculptures that paint\"). According to Wikipedia, visitors made about 4,000 drawings and at least five to six thousand people came; there was a competition for the best drawing made on a Méta-Matic, judged by a jury that included Hans Arp, Yves Klein and the critic Pierre Restany.\n\nFor the Paris Biennale the same year Tinguely built Méta-Matic No. 17. It is large, 330 × 170 × 190 cm, of painted iron and wood, with a petrol engine whose exhaust slowly fills a balloon until it bursts. The Moderna Museet, which received it as a gift from its Friends in 1965, says that it \"dances, makes noises and incessantly spits out ink drawings\".\n\nMachines that draw, with and without computers\n\nA Méta-Matic and a pen plotter both move a pen over paper with motors, but they answer to different things. A plotter such as the Zuse Graphomat Z64 follows coordinates calculated in advance by a program, and the same program gives the same drawing every time unless it calls on random numbers. A Méta-Matic has no coordinates and no program: what it draws comes from the mechanism and the tools the visitor puts in it. Other mechanical drawing machines of the time, built from military calculators, are described in Desmond Paul Henry's drawing machines and John Whitney's Catalog.\n\nMetamatic Reloaded, shown at the Museum Tinguely in Basel in 2013–14, brought together ten new works by artists including Marina Abramović and Thomas Hirschhorn; they came from an open call in 2009 to rethink the drawing machines from today's point of view."},
{"type": "note", "title": "Moiré patterns", "url": "https://jaev.gallery/notes/moire-patterns/",
   "description": "Moiré: the broad bands that appear where two fine sets of lines overlap. How they form, how wide they are, and their place in Swedish computer art.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "moiré pattern", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q26468"}], "mentions": [{"name": "Sten Kallin", "type": "Person", "sameAs": null}, {"name": "Astrid Sampe", "type": "Person", "sameAs": null}, {"name": "Sture Johannesson", "type": "Person", "sameAs": null}],
   "sources": [{"title": "“Moiré pattern”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Moir%C3%A9_pattern"}, {"title": "Sten Kallin, interviewed by Anna Orrghen, 10 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "Sture Johannesson and Ann-Charlotte Johannesson, interviewed by Anna Orrghen, 2 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/4-ann-charlotte-och-sture-johannesson.pdf"}],
   "related": {"notes":["astrid-sampe-computer-textile","sture-johannesson","line-hatching","ibm-1130-swedish-computer-art"],"editorial":["computer-art-in-sweden","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/moire-patterns-jaev.jpg", "alt": "A wide rectangle of fine, nearly vertical black lines on warm paper. On the left only one set of lines is drawn, on the right only a second set at a slightly different angle. In the middle third, where both sets overlap, broad dark and light diagonal bands appear.", "credit": "Diagram by JAEV: two identical sets of parallel lines, 5 px apart, the second turned by 3 degrees. Each set is seen alone at one side; the moiré bands appear only where they overlap. CC BY 4.0."},
   "text": "A moiré is a pattern of broad light and dark bands that appears when two fine, regular sets of lines lie on top of each other. Neither set contains the bands. They come from the way the two sets cross: where the lines fall on top of each other, more paper shows and the area looks light; where they fall between each other, they cover more paper and the area looks dark. The word comes from French moiré, a fabric, historically silk, with a rippled \"watered\" look.\n\nHow wide the bands are\n\nThe bands are much wider than the lines that make them, and their width follows from two numbers. Take two identical sets of parallel lines with spacing p and turn one by a small angle α. The light bands are then\n\nD = (p/2) / sin(α/2)\n\napart, which for small angles is close to p/α (with α in radians). Lines 5 px apart, turned by 3 degrees, give bands about 95 px apart, as in the drawing at the top of this page. The smaller the angle, the wider the bands.\n\nThat magnification is why moiré is used to measure. A grid printed on a material and compared with an undeformed grid shows strain in the material as bands. It is also why it is a nuisance: in printing, the dot screens of the different inks are set at chosen angles to avoid it; and patterned clothes can make it appear on television.\n\nNew drawing\nLive sketch by JAEV: two identical sets of lines, the top one moving slowly. With straight lines it turns between about half a degree and six and a half degrees; with concentric circles it slides sideways. The bands move much faster and further than the lines themselves. Each drawing switches between the two and takes a new random spacing. Code CC BY 4.0.\n\nOn the plotter\n\nA pen plotter makes moiré easily, because it draws many fine lines close together. When the textile designer Astrid Sampe asked IBM to help her draw a red cross by computer, the programmer Sten Kallin noticed that the pen of the IBM 1130's plotter sat a little loose in its holder, so its slanted lines were never quite straight. Laid next to each other, he said, such lines were strengthened by \"the moiré effect that arises when you have several lines next to each other, especially if they do not have quite the same angle\". He wrote a program that drew the cross many times, each time smaller and turned.\n\nKallin went on to make computer pictures with the artist Sture Johannesson, among them the project INTRA. Looking back in 2007 he said that what interested him was how lines \"that are regular but not too regular\" work together to make moiré-like patterns: \"It has always amused me a lot.\" The story is told in full in the editorial Computer Art in Sweden. For drawing tone with many lines on a plotter, see line hatching and Plotter Art."},
{"type": "note", "title": "MusicBox (Knut Wiggen, EMS Stockholm, 1971–75)", "url": "https://jaev.gallery/notes/knut-wiggen-musicbox/",
   "description": "MusicBox was Knut Wiggen's composition program at EMS in Stockholm: music as a network of boxes that pass numbers on. How it worked, and a live sketch.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "MusicBox", "type": "Thing", "sameAs": null}, {"name": "Knut Wiggen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6240816"}], "mentions": [{"name": "Elektronmusikstudion", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q3672234"}, {"name": "Fylkingen", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q5511234"}, {"name": "PDP-15", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q40887513"}],
   "sources": [{"title": "Jøran Rudi, “Unpacking the Musical and Technical Innovation of Knut Wiggen”. Organised Sound 23 (2), 2018, pp. 195–207", "url": "http://www.knut-wiggen.com/Texts/Rudi_OS_23.3.pdf"}, {"title": "Jøran Rudi, “Knut Wiggen”. Store norske leksikon", "url": "https://snl.no/Knut_Wiggen"}, {"title": "Jan W Morthenson, interviewed by Anna Orrghen, 17 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/6-jan-w-morthenson.pdf"}, {"title": "Knut Wiggen, Electronic Works 1972–1975. LP, O. Gudmundsen Minde (OGM005), 2018, sleeve notes by Jøran Rudi", "url": "http://www.knut-wiggen.com/Texts/Sleeve-note-Wiggen-LP.pdf"}, {"title": "Lars-Gunnar Bodin, interviewed by Anna Orrghen, 5 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/26-lars-gunnar-bodin.pdf"}],
   "related": {"notes":["lars-gunnar-bodin","jan-w-morthenson","sha-256-as-random-source","ibm-1130-swedish-computer-art"],"editorial":["computer-art-in-sweden","generative-art","the-rule-is-the-work"],"exhibitions":["content"]},
   "image": {"url": "https://jaev.gallery/assets/notes/ems-control-desk-norsk-teknisk-museum-bjoertvedt.jpg", "alt": "A wide control desk under clear plastic covers in a museum, with grids of orange push-buttons, a row of sliders along the back and labelled panels.", "credit": "Control desk from the Elektronmusikstudion (EMS) in Stockholm, the studio Knut Wiggen built, on display at Norsk Teknisk Museum, Oslo. Photo: Bjoertvedt, CC BY-SA 3.0, via Wikimedia Commons."},
   "text": "MusicBox was a composition program written for the Elektronmusikstudion (EMS) in Stockholm under its director, the Norwegian-born composer Knut Wiggen. The first version was finished in 1971. In MusicBox a piece of music was not a list of notes but a network of boxes, each holding a mathematical function, that passed numbers on to each other.\n\nThe studio\n\nWiggen (1927–2016) led the Stockholm concert society Fylkingen from 1959 and built up EMS from 1964. EMS was a hybrid studio: analogue oscillators, filters and reverbs controlled by a computer, a PDP-15 bought in 1970.\n\nComposing meant typing numbers. With the studio's language EMS-1, each event was described line by line, on a teleprinter that punched paper tape. The composer Lars-Gunnar Bodin remembers another program on the same machine where one forgotten semicolon spoiled a whole session. Jan W Morthenson called the work \"very cumbersome for making a single sound\".\n\nHow MusicBox worked\n\nAs Rudi points out, typing numbers for pitch and duration is not much different from writing notes. Wiggen wanted the composer to work with rules and structure instead. In MusicBox each box took a number in, applied its function and sent the result to the next box. Small boxes could be wrapped into larger ones and reused, so that complex events came out without any pitch being written down. MusicBox was written in Fortran. The programmer David Fahrland wrote the first version; Kaj Beskow added sound moving between four loudspeakers, and Zaid Holmin better macros.\n\nRudi describes the score of Sommarmorgon (1972), the first study. A Gauss box sends out an irregular stream of numbers between 35 and 14,000, bell-shaped, so that low numbers are rare. If boxes sort the stream into three ranges: below 200, 200 to 1,600, and 1,600 to 14,000. In each range Choice boxes pick a duration and a waveform from fixed lists by weighted chance, and the number itself becomes the frequency. The rare low numbers get the long durations, so in the piece a dark tone is also a long tone. Half of them have a waveform other than a sine; the high range plays only short sine tones. Two realisations exist, made with different random seeds: different, and recognisably the same piece.\n\nNew drawing\nReconstruction by JAEV after Rudi's description of the box network for Sommarmorgon: one minute drawn as a score, time left to right, pitch from 35 to 14,000 Hz bottom to top, each line one tone as long as it lasts, thick lines for waveforms other than a sine. The spread of the Gauss box, the lists of durations and their weights, and the gaps between tones are JAEV's choices; Wiggen's values are not published. It draws; it does not play. Code CC BY 4.0.\n\nFive studies, then nothing\n\nWiggen made five studies with MusicBox: Sommarmorgon, Etyd and Resa (1972), Massa (1974) and EMS för sig själv (1975). They were composed for four channels. Resa was played at MIT in 1976, at the first international conference on computer music.\n\nThe program was never given to other composers. A new board wanted EMS to serve composers' immediate needs, and Wiggen resigned in 1975. He took the code with him, partly because EMS did not want it and partly so that it would not be used for \"elevator music\". Rudi compares the idea to Max and Pd, where music is also made by connecting boxes. The five pieces were issued on an LP in 2018, in new stereo mixes.\n\nIn JAEV's exhibition Content, numbers from a hash of the day's text choose among fixed options in a similar way; see SHA-256 as a random source."},
{"type": "note", "title": "Openly licensed photographs as material", "url": "https://jaev.gallery/notes/commons-images-as-material/",
   "description": "What CC0 and CC BY allow, what attribution means, where openly licensed photographs are found, and how artists combine many of them into one image.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Creative Commons license", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q284742"}, {"name": "Wikimedia Commons", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q565"}], "mentions": [{"name": "Creative Commons", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q43449"}, {"name": "Creative Commons Attribution 4.0 International", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q20007257"}, {"name": "Creative Commons CC0 License", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q6938433"}, {"name": "composite portrait", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q12410888"}, {"name": "Francis Galton", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q191026"}],
   "sources": [{"title": "“Creative Commons license”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Creative_Commons_license"}, {"title": "“About CC”. Creative Commons", "url": "https://creativecommons.org/about/"}, {"title": "“Attribution 4.0 International (CC BY 4.0)”, licence deed. Creative Commons", "url": "https://creativecommons.org/licenses/by/4.0/deed.en"}, {"title": "“CC0”. Creative Commons", "url": "https://creativecommons.org/public-domain/cc0/"}, {"title": "Wikimedia Commons, Main Page. Retrieved 20 October 2026", "url": "https://commons.wikimedia.org/wiki/Main_Page"}, {"title": "“Group Photo 0121”, Olof Broström, 19 October 2026. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/group-photos/0121/"}, {"title": "“Composite portrait”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Composite_portrait"}, {"title": "“Group Photos”, Olof Broström. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/group-photos/"}],
   "related": {"notes":["air-quality-data-as-art-material","sha-256-as-random-source"],"editorial":["generative-art","sol-lewitt"],"exhibitions":["group-photos"]},
   "image": {"url": "https://jaev.gallery/assets/notes/commons-images-as-material-olof-brostrom-group-photo-0121.jpg", "alt": "A dense, layered photograph in greens and ochres: fern-like leaves, grass stems, a small white star-shaped flower on the right and a dried brown flower head at the bottom, blended so that sharp details from different photographs sit side by side.", "credit": "Olof Broström, Group Photo 0121, 2026. JAEV. Combined from ten photographs by elik03, William Harland, Philip Precey, John Barkla, Stilgherrian, WATANABE Hitoshi 渡辺仁, Jason Grant, Louis Aureglia, SatNavSaysStraightOn and Katrin Simon (CC BY and CC0), listed on the work's page."},
   "text": "An openly licensed photograph is one whose photographer has said in advance that anyone may use it, under conditions written into a standard licence. Standard licences of this kind come from Creative Commons. The first versions were released on 16 December 2002, and according to the organisation tens of billions of works now carry one. Two of its tools leave an artist free to cut, combine and sell: CC BY and CC0.\n\nWhat the licences allow\n\nCC BY 4.0 (released in November 2013) lets anyone copy and redistribute the material and \"remix, transform, and build upon\" it, for any purpose, even commercially. The condition is attribution: give appropriate credit, provide a link to the licence, and indicate if changes were made.\n\nCC0 (released in 2009) is a waiver rather than a licence with conditions: the photographer gives up all copyright and related rights as far as the law allows. No attribution is required, though users may give it.\n\nWhere the photographs are\n\nOne large collection is Wikimedia Commons, a free media repository to which anyone can contribute, which on 20 October 2026 held 149,797,865 freely usable files. Other platforms record a licence for each photograph separately, so a program can ask for only CC0 and CC BY images and leave the rest. Each photograph then carries its licence and its photographer's name as data, which a program can print next to the result as easily as it reads the image.\n\nMany photographs, one image\n\nLaying many photographs over each other is an old method. In the late nineteenth century Francis Galton exposed several portraits on the same photographic plate to make a composite portrait, and used it to try to define the faces of health, disease, beauty and criminality. The method averages: what the pictures share stays, what is particular to each fades.\n\nThe alternative is to keep, at every point of the image, whichever photograph is sharpest there, so nothing is averaged away. Each photographer's subject, the thing they focused on, survives, and the blurred backgrounds give way.\n\nWhere to see it\n\nOlof Broström's Group Photos does this once a day on JAEV's server. Ten photographs are drawn at random from those uploaded that day to a public platform where people share observations of plants, animals and fungi, each by a different photographer and each with a free licence, and combined by sharpness. Group Photo 0121, made on 19 October 2026, was drawn from 5,729 photographs posted that day; its page lists the ten sources, each with its share of the image, its photographer and its licence, CC BY or CC0."},
{"type": "note", "title": "Perlin noise (Ken Perlin, 1983)", "url": "https://jaev.gallery/notes/perlin-noise/",
   "description": "Perlin noise is a random function Ken Perlin made in 1983 for film textures: how its grid of gradients works, and why it is zero at every grid point.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Perlin noise", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1404167"}], "mentions": [{"name": "Ken Perlin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6388302"}, {"name": "Academy Award for Technical Achievement", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q8636"}, {"name": "simplex noise", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q7520885"}],
   "sources": [{"title": "Peter Kirn, “Bespoke visual noise is the next domain for Robert Henke, so let's revisit Perlin anyway”. CDM, 10 January 2022", "url": "https://cdm.link/bespoke-visual-noise-is-the-next-domain-for-robert-henke-so-lets-revisit-perlin-anyway/"}, {"title": "“Perlin noise”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Perlin_noise"}, {"title": "Ken Perlin, “Noise and Turbulence” (Academy Award page). NYU Media Research Lab", "url": "https://mrl.cs.nyu.edu/~perlin/doc/oscar.html"}, {"title": "Ken Perlin, “Improving Noise”. SIGGRAPH 2002 (PDF, NYU Media Research Lab)", "url": "https://mrl.cs.nyu.edu/~perlin/paper445.pdf"}, {"title": "Ken Perlin, “Improved Noise reference implementation”, 2002. NYU Media Research Lab", "url": "https://mrl.cs.nyu.edu/~perlin/noise/"}, {"title": "“noise()”. Processing reference", "url": "https://processing.org/reference/noise_.html"}, {"title": "Tyler Hobbs, “Flow Fields”, 3 February 2020", "url": "https://www.tylerxhobbs.com/words/flow-fields"}],
   "related": {"notes":["flow-fields","line-hatching","sha-256-as-random-source"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/perlin-noise-jaev.jpg", "alt": "A grid of 8 by 5 squares covered with thin black contour lines that wind into rounded hills and hollows. At every grid point a black dot with a short thick line shows the gradient there, and a thicker red line, the value zero, passes through every grid point at right angles to its gradient.", "credit": "Diagram by JAEV: two-dimensional Perlin noise written after Perlin's 2002 description, with eight gradient directions. Short thick lines: the gradient at each grid point. Thin lines: contours in steps of 0.1. Red: the value 0. CC BY 4.0."},
   "text": "Perlin noise is a function that gives a smoothly varying, random-looking value for every point in space. Ken Perlin made it in 1983 to give computer images a less mechanical surface. He described it in the SIGGRAPH paper \"An Image Synthesizer\" in 1985 and received an Academy Award for it in 1997.\n\nWhy it was made\n\nPerlin began thinking about procedural textures, patterns computed rather than painted, while working on Tron at MAGI in Elmsford, New York, in 1981. \"On some level I was frustrated by the fact that everything looked machine-like,\" he later said. \"The first thing I did in 1983 was to create a primitive space-filling signal that would give an impression of randomness.\"\n\nHow it works\n\nIn two dimensions:\n\nA grid with a direction at every point. The integer grid points each get a pseudo-random gradient, an arrow of length one. Perlin picks the arrow by passing the point's coordinates through a shuffled table of the numbers 0 to 255, so the same point always gets the same arrow.\n\nFour corner values. For a point inside a grid square, each of the square's four corners gives a number: the dot product of the corner's arrow with the line from the corner to the point. The number is large when the point lies in the direction the arrow points, negative when it lies behind, and zero at the corner itself.\n\nA smooth blend. The four numbers are mixed according to where the point lies in the square, through an S-shaped curve so that there are no kinks at the edges of the squares.\n\nBecause every corner contributes zero at its own position, the noise is zero at every grid point. In the sketch below this is visible: the thick line, where the value is exactly zero, passes through every grid point, at right angles to that point's arrow.\n\nNew drawing\nLive sketch by JAEV: two-dimensional Perlin noise on a 5 × 5 grid, written by JAEV after Perlin's 2002 description, with eight gradient directions instead of his twelve (which are for three dimensions). Short thick lines: the gradient at each grid point. Thin lines: contours of the noise in steps of 0.1. Thick line: the value 0. Code CC BY 4.0.\n\nImproved noise, 2002\n\nIn \"Improving Noise\" (SIGGRAPH 2002) Perlin corrected \"two deficiencies in the original Noise algorithm\". The original blending curve was 3t² − 2t³. Its second derivative, 6 − 12t, is not zero at the edges of a square, which shows up as visible creases when a surface shaped by noise is shaded. He replaced it with 6t⁵ − 15t⁴ + 10t³, and simplified the choice of gradients to a small fixed set of directions. His reference code in Java is on his NYU page.\n\nIn generative art\n\nThe programming tool Processing has it built in: noise() \"Returns the Perlin noise value at specified coordinates\", adding several octaves together. In flow fields, \"About 90% of the time, people use Perlin noise to initialize the vectors,\" according to the artist Tyler Hobbs. The noise is not random in the sense of a dice throw: the same input always gives the same output, and the randomness lies in the shuffled table. For a source of chance that comes from outside the program, see the note on SHA-256 as a random source; for the wider field, the editorial Generative Art."},
{"type": "note", "title": "Plotter path optimisation", "url": "https://jaev.gallery/notes/plotter-path-optimisation/",
   "description": "Why the order of lines matters to a pen plotter, how a greedy nearest-neighbour sort cuts the pen's travel in the air, and its link to the travelling salesman.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "travelling salesperson problem", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q322212"}, {"name": "nearest neighbour algorithm", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1374523"}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "vpype", "type": "Thing", "sameAs": null}, {"name": "saxi", "type": "Thing", "sameAs": null}],
   "sources": [{"title": "Olof Broström, Unverified Air, no. 11 (Schiedam-Alphons Arienstraat), 14 October 2026. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/0011/"}, {"title": "“Travelling salesman problem”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Travelling_salesman_problem"}, {"title": "“Nearest neighbour algorithm”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Nearest_neighbour_algorithm"}, {"title": "“Command reference”. vpype documentation", "url": "https://vpype.readthedocs.io/en/latest/reference.html"}, {"title": "saxi", "url": "https://github.com/nornagon/saxi"}, {"title": "Jeremy Rose, author of saxi, email to JAEV, 22 October 2026", "url": "https://github.com/nornagon/saxi"}, {"title": "“AxiDraw CLI & Python API”", "url": "https://axidraw.com/doc/cli_api/"}, {"title": "Matto, Time Between the Lines is Thread Through the Mind. Art Blocks, 2024", "url": "https://www.artblocks.io/marketplace/collections/time-between-the-lines-is-thread-through-the-mind-by-matto"}],
   "related": {"notes":["line-hatching","hp-gl","flow-fields"],"editorial":["plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/plotter-path-optimisation-jaev.jpg", "alt": "Two squares with the same 150 short black strokes. In the left square, dashed red lines criss-cross the whole square between the strokes; in the right square, the dashed red lines are short hops from each stroke to its neighbour. Labels below read: as generated: pen up 7,140 mm; nearest neighbour: pen up 897 mm.", "credit": "Diagram by JAEV: the same 150 random strokes in the order they were generated (left) and after a greedy nearest-neighbour sort with reversal allowed (right). Black: pen down. Dashed red: pen up, from the top left corner. Each square counted as 100 mm across. CC BY 4.0."},
   "text": "Path optimisation is the step that puts the lines of a plotter drawing in a better order, and turns some of them round, so that the pen spends less time moving in the air between them. Finding the best order is a version of the travelling salesman problem, so in practice plotter software such as vpype uses a fast rule that gives a good order rather than the best one.\n\nThe problem\n\nA pen plotter draws lines in exactly the order it receives them. After each line it lifts the pen and moves to the start of the next (see Plotter Art and the note on HP-GL). A program that generates a drawing usually writes its lines in the order it computed them, which can send the pen back and forth across the sheet thousands of times. A single drawing in Olof Broström's Unverified Air, no. 11, has 4,218 lines in three pens.\n\nThe travelling salesman problem asks for \"the shortest possible route that visits each city exactly once and returns to the origin city\". It is NP-hard, which in practice means that no known method finds the best route quickly once there are many cities. For a plotter, each line is a city with two doors: the pen can start at either end.\n\nGreedy nearest neighbour\n\nThe simplest useful rule is the nearest-neighbour algorithm: from where you are, always go to the nearest place not yet visited. Adapted to lines, it reads: start where the pen is. Among the lines not yet drawn, find the one with an end closest to the pen. If that is the line's far end, reverse the line. Draw it, and repeat from where it ends. The algorithm \"quickly yields a short tour, but usually not the optimal one\", and for some arrangements it gives a route much longer than the best.\n\nThe cost of the rule grows with the square of the number of lines: a drawing of 10,000 lines needs some 50 million checks.\n\nNew drawing\nLive sketch by JAEV: the same 150 random strokes in the order they were generated (left) and after a greedy nearest-neighbour sort with reversal allowed (right). Solid lines are the pen down, dashed lines the pen up, starting from the top left corner. Distances assume each square is 100 mm across. Code CC BY 4.0.\n\nIn the tools\n\nThe plotter program vpype sorts lines with the command linesort: \"By default, a fast, greedy algorithm is used\", and it reverses a line \"if it can further optimize the pen-up distance\". An option, --two-opt, runs a further optimisation after the greedy pass. The plotter driver saxi \"minimizes pen-up travel time by reordering & reversing paths\". Its author, Jeremy Rose, says he worked out the optimisation from his own experiments, and that saxi had it a couple of years before vpype; he thinks vpype may well have arrived at the same, fairly obvious, method independently. The AxiDraw software has five settings, from \"Strictly preserve file order\" to \"Full; Also allow path reversal\"; by default it only joins paths that meet.\n\nWhen not to sort\n\nSorting changes how a drawing is made, and some artists treat that as part of the work. For the Art Blocks project Time Between the Lines is Thread Through the Mind (2024), the artist Matto asks those who plot it to \"maintain the drawing order for canonical outputs - avoid reordering or optimizing the paths during plotting\".\n\nFills made of hatching and curves from flow fields are two common sources of many short lines, and so of long pen-up journeys."},
{"type": "note", "title": "Plotter pens, from ballpoints to fineliners", "url": "https://jaev.gallery/notes/plotter-pens/",
   "description": "Which pens plotters have drawn with since the 1960s: the IBM 1627's ballpoint, HP and Roland cartridges, drafting pens and today's fineliners.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}, {"name": "technical pen", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1420532"}], "mentions": [{"name": "Hewlett-Packard", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q80978"}, {"name": "ballpoint pen", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q160137"}, {"name": "marker pen", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q493615"}, {"name": "fountain pen", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q192401"}, {"name": "Sten Kallin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q133612844"}, {"name": "Roland DG", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q2162714"}, {"name": "Evil Mad Scientist", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q109968929"}],
   "sources": [{"title": "“1627 Plotter”. IBM 1130 Functional Characteristics, transcribed at ibm1130.net", "url": "http://www.ibm1130.net/functional/Plotter.html"}, {"title": "Sten Kallin, interview by Anna Orrghen, 2007. Tekniska museet, Stockholm (PDF)", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "HP 7475A Plotter Operation Manual. Hewlett-Packard, via the Internet Archive", "url": "https://archive.org/details/HP7475AOperationManual"}, {"title": "Roland DXY-990 Operation Manual. Roland DG, via the Internet Archive", "url": "https://archive.org/details/roland-dxy-990"}, {"title": "“Pens for AxiDraw”. Evil Mad Scientist wiki", "url": "https://wiki.evilmadscientist.com/Pens_for_AxiDraw"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["calcomp-565","hp-7475a","roland-dxy-plotters","axidraw","line-hatching"],"editorial":["plotter-art","computer-art-in-sweden"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/plotter-pens-alps-mogor.jpg", "alt": "Four short metal pen cartridges standing in a row on a white surface, each with a coloured conical tip: green, blue, black and red. Below them lies a wooden match with a brown head, a little longer than the four pens are wide together.", "credit": "Four pens of the kind used in small plotters built on an ALPS mechanism, with a match for scale. Photo: Mogor, CC BY-SA 4.0, via Wikimedia Commons."},
   "text": "A pen plotter draws with a real pen, and the pen decides much of what the drawing looks like: the width of the line, how dark it is, whether it skips, and how fast the machine may move. Plotters have drawn with ballpoints, felt and fibre tips, refillable drafting pens and, today, almost any pen that fits the holder.\n\nBallpoints on the drum\n\nIBM's 1627 drum plotter (see the note on the CalComp 565) came with a ballpoint pen that lasted \"about five or six hours of continuous plotting\"; a liquid ink pen was an option. In Stockholm, Sten Kallin drew on a drum plotter with an IBM 1130. He remembered that the pen \"kunde vara en kulspetspenna eller en bläckpenna eller färgpenna eller vad du vill\": a ballpoint, an ink pen, a colour pen or whatever you like. It sat a little loose in its holder, so a line built from small steps came out \"lite mänskligt\", a little human: \"lite karaktär eller lite slump i strecket\", a bit of character or a bit of chance in the line. His work with Astrid Sampe is described in Computer art in Sweden.\n\nCartridges and carousels\n\nThe desktop plotters of HP and Roland took pens made for them, kept in the machine in a carousel or in clips. The HP 7475A of 1983 took three kinds: disposable fibre-tip pens for paper, fibre-tip pens for overhead film, and refillable drafting pens with tungsten carbide points, which drew the best lines but needed cleaning after each use. HP recommended 38 cm a second for fibre tips on plain plotter paper and 10 cm a second on glossy paper and film.\n\nRoland's DXY plotters had their own range. The DXY-990's water-based fibre tips could draw at up to 300 mm a second, but their tips wore down and the lines grew wider. Ceramic-tipped pens of 0.2, 0.4 and 0.6 mm kept \"a precise line width\" until the ink ran out, at a recommended 150 mm a second. A mechanical \"soft landing\" lowered the pen gently enough for ink drafting pens, and the machine capped each pen when it returned to its clip.\n\nAny pen that fits\n\nNew plotters such as the AxiDraw need no special pens. The AxiDraw holds a pen up to 16 mm across and 45 g, and Evil Mad Scientist's list of pens that work includes fountain pens, the Pilot Precise V5 rollerball, Sharpie Ultra Fine Point markers, Pigma Micron fineliners, gel pens and technical pens. Its notes on them: technical pens must stand vertically on the paper, gel pens may skip on textured paper, ballpoints work unevenly because they need more pressure than the machine gives, and felt tips wear down.\n\nOlof Broström's Unverified Air at JAEV is stored as files for a pen plotter, in black, red and blue ink."},
{"type": "note", "title": "Poisson disc sampling", "url": "https://jaev.gallery/notes/poisson-disc-sampling/",
   "description": "Poisson disc sampling scatters points at random, never closer than a set distance. Why plain randomness clumps, Bridson's 2007 algorithm, a sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "blue noise", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q12345729"}], "mentions": [],
   "sources": [{"title": "Robert Bridson, “Fast Poisson Disk Sampling in Arbitrary Dimensions”. SIGGRAPH 2007 sketches, University of British Columbia", "url": "https://www.cs.ubc.ca/~rbridson/docs/bridson-siggraph07-poissondisk.pdf"}, {"title": "Mike Bostock, “Visualizing Algorithms”, 26 June 2014", "url": "https://bost.ocks.org/mike/algorithms/"}],
   "related": {"notes":["voronoi-delaunay","weighted-voronoi-stippling","circle-packing","random-walk"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/poisson-disc-sampling-jaev.jpg", "alt": "Two squares of small circles with a dot in each, on warm paper. Left: the circles lie at random, many overlapping in red clusters with empty gaps between them. Right: the same number of black circles spread evenly, touching at most, never overlapping.", "credit": "Diagram by JAEV. Right: 127 points from Bridson's algorithm, minimum distance r, each with a circle of radius r/2. Left: 127 points placed uniformly at random with the same circles; red where circles overlap. CC BY 4.0."},
   "text": "Poisson disc sampling places points at random in an area, with one rule: no two points may be closer than a chosen distance r. The result looks random but even, without clumps and without large gaps. In computer graphics such patterns are used to decide where to sample an image. A simple fast method was published by Robert Bridson of the University of British Columbia in 2007.\n\nWhy plain randomness looks wrong\n\nIf each point is placed by choosing its x and y at random, every point ignores all the others. As Mike Bostock puts it, \"many samples are densely-packed, even overlapping, leading to large empty areas\". In the image at the top, each point has a circle of half the minimum distance around it. On the left, where the points are simply random, the red circles overlap; on the right, made by Bridson's algorithm, the circles may touch but never overlap.\n\nPoint patterns of the second kind are called blue noise, and Bridson notes that they are \"generally considered ideal for many applications in rendering\", pointing to Cook's \"landmark paper\" of 1986.\n\nBridson's algorithm\n\nThe simplest method, \"dart throwing\", keeps choosing random points and throws away any that land too close to an existing one. Bridson calls it \"impractically inefficient\". His version looks for new points only next to points already placed:\n\nA grid. Cover the area with square cells of side r/√2. A cell that size can hold at most one point, so checking for neighbours means looking at only a few cells.\n\nA first point, anywhere at random. Put it on an \"active list\".\n\nGrow. Pick a random point from the active list. Try up to k random candidates (typically 30) in the ring between distance r and 2r around it. Keep the first candidate that has no point within r, and add it to the active list. If none of the k fits, remove the point from the list: there is no room left around it.\n\nStop when the active list is empty.\n\nEach round either adds a point or retires one, so the running time grows in proportion to the number of points. Bridson's point was that the same steps work in three or more dimensions.\n\nNew drawing\nLive sketch by JAEV. Right: Bridson's algorithm with k = 30, the points appearing in the order the algorithm finds them, each with a circle of radius r/2. Left: the same number of points placed uniformly at random; dashed circles overlap another. Code CC BY 4.0.\n\nIn drawings\n\nFor a drawing, the method gives positions for dots or small marks that are spread evenly without lining up in a grid. The points can also be the sites of a Voronoi diagram, and evenly spread dots are the aim of weighted Voronoi stippling. See also Generative art."},
{"type": "note", "title": "Processing (Ben Fry and Casey Reas, 2001)", "url": "https://jaev.gallery/notes/processing/",
   "description": "Processing, started in 2001 by Ben Fry and Casey Reas at the MIT Media Lab, is a free language for drawing with code. Its origins, and how a sketch runs.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-22",
   "author": "JAEV Editorial",
   "about": [{"name": "Processing", "type": "SoftwareApplication", "sameAs": "https://www.wikidata.org/wiki/Q1053535"}], "mentions": [{"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}, {"name": "Ben Fry", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4888685"}, {"name": "John Maeda", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q93024"}, {"name": "MIT Media Lab", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1373549"}, {"name": "Processing Foundation", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q56057168"}, {"name": "p5.js", "type": "SoftwareApplication", "sameAs": "https://www.wikidata.org/wiki/Q59555213"}],
   "sources": [{"title": "Ben Fry and Casey Reas, “Overview”. Processing.org (updated 14 September 2022)", "url": "https://processing.org/overview"}, {"title": "Liz Stinson, “Processing: the Software that Shaped Creative Coding”. AIGA Eye on Design, 28 October 2021", "url": "https://eyeondesign.aiga.org/processing-the-software-that-shaped-creative-coding/"}, {"title": "“Processing”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Processing"}, {"title": "“setup()” and “draw()”. Processing reference", "url": "https://processing.org/reference/draw_.html"}, {"title": "“SVG Export”. Processing reference", "url": "https://processing.org/reference/libraries/svg/index.html"}, {"title": "“noise()”. Processing reference", "url": "https://processing.org/reference/noise_.html"}],
   "related": {"notes":["design-by-numbers","perlin-noise","flow-fields","vpype"],"editorial":["casey-reas","generative-art","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/processing-jaev.jpg", "alt": "Left: a short Processing program in black monospace type, with a setup function that makes a 400 by 400 window and a draw function that draws one line per frame and stops after 66 frames. Right: what it draws, 66 thin black lines that all cross at the centre of a square, forming an hourglass.", "credit": "Diagram by JAEV: a short Processing sketch (JAEV's own example) and the drawing it makes, computed exactly as the code says. CC BY 4.0."},
   "text": "Processing is a free programming language and editor for making pictures, animations and interactive work with code. Casey Reas and Ben Fry started it in spring 2001, when both were graduate students in John Maeda's Aesthetics and Computation group at the MIT Media Lab. It has been open source from the start and runs on Mac, Windows and Linux.\n\nWhere it came from\n\nProcessing \"grew directly out of\" Design by Numbers, the teaching language Maeda had released in 1999, on which Fry and Reas had worked as research assistants. Processing's early editor reused the interface of Design by Numbers, but the language underneath was Java, with simplifications.\n\nA Processing program is called a sketch, and the folder of programs a sketchbook. Reas explained the choice of words: the aim was \"to make the creation process a little bit more informal\". The first release is dated by the Processing project to August 2001.\n\nHow a sketch runs\n\nMost sketches have two parts. setup() is \"run once, when the program starts\": it sets the size of the window and anything else that only needs doing at the beginning. draw() is then called again and again, once per frame, until the program stops or calls noLoop(). The screen is updated at the end of each draw().\n\nThe example in the picture above uses this. Each time draw() runs, it adds one line, and because the window is never cleared, the lines add up into a drawing. The live version below works the same way in your browser.\n\nNew drawing\nSketch by JAEV of the setup() and draw() pattern: setup() clears the drawing once, then draw() runs 30 times a second and adds one line from (x, 0) to (400 − x, 400), with x = frameCount × step, until the line reaches the edge. Each new drawing picks a new step and a new pair of edges. Written in JavaScript, not Processing itself. Code CC BY 4.0.\n\nWhat grew from it\n\nPeople who use Processing have written more than a hundred libraries for it, and in 2012 Fry and Reas started the Processing Foundation to support it. In 2013 Lauren McCarthy created p5.js, which brings the same ideas to JavaScript and the web, with the Foundation's support. Processing's SVG export is one common way to get a drawing from code onto a pen plotter, as JAEV's Plotter art describes. Some methods in JAEV's Notes are built into Processing, such as Perlin noise, which noise() returns."},
{"type": "note", "title": "Punched paper tape", "url": "https://jaev.gallery/notes/punched-paper-tape/",
   "description": "How punched paper tape carried programs and plotter drawings in the 1960s: the eight-track standard, Nake's Graphomat tape, a compiler on tape.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "punched tape", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q66241"}], "mentions": [{"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "Sten Kallin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q133612844"}, {"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}, {"name": "Graphomat Z64", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q130493775"}, {"name": "IBM 1620", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q955489"}],
   "sources": [{"title": "ECMA-10, Data Interchange on Punched Tape, November 1965. Ecma International (OCR transcription by Joseph Myers)", "url": "https://polyomino.org.uk/computer/ECMA-10/"}, {"title": "“Project Zuse”. Computer Museum, Department of Computer Science, University of Stuttgart", "url": "https://www.f05.uni-stuttgart.de/en/cs/department/computer-museum/projects-and-information/project-zuse/"}, {"title": "Georg Nees, Schotter, 1968–1970. Victoria and Albert Museum, London (catalogue text)", "url": "https://collections.vam.ac.uk/item/O221321/schotter-print-nees-georg/"}, {"title": "Frieder Nake and Wolf Lieser, “60 Years of Algorithmic Art”. Digital Art Museum (DAM), Berlin", "url": "https://dam.org/museum/essays_ui/essays/frieder-nake-wolf-lieser-60-years-of-algorithmic-art/"}, {"title": "Sten Kallin, interview by Anna Orrghen, 2007. Tekniska museet, Stockholm (PDF)", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "PLOT-10 Terminal Control System User's Manual (062-1474-00), April 1972. Tektronix, via Bitsavers and the Internet Archive", "url": "https://archive.org/details/bitsavers_tektronixp0TerminalControlSystem4010UsersManualApr_5470592"}, {"title": "Manfred Mohr, “Météorologie Nationale”", "url": "https://emohr.com/paris-1971/meteo.html"}],
   "related": {"notes":["zuse-graphomat-z64","frieder-nake-hommage-a-paul-klee","georg-nees-schotter","tektronix-4010","ibm-1130-swedish-computer-art"],"editorial":["plotter-art","computer-art-in-sweden","georg-nees","manfred-mohr"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/punched-paper-tape-5-and-8-hole-tedcoles.jpg", "alt": "Two loose rolls of punched paper tape on a white surface: a narrower cream-coloured one on the left and a wider pink one on the right. Both are punched with rows of round holes across the tape, with a line of smaller holes running along each.", "credit": "Five-hole (left) and eight-hole paper tape. Photo: TedColes, public domain, via Wikimedia Commons."},
   "text": "Punched paper tape is a long strip of paper in which a machine punches rows of holes. Each row across the tape holds one character, coded by which positions in the row are punched. Tape carried programs and data between computers, and it carried some of the first plotter drawings shown as art to the plotter: the drawing existed as holes in paper before a pen drew it.\n\nHow the tape is laid out\n\nThe European standard ECMA-10 of 1965 describes the tape used to exchange data between computers. It is 25.4 mm wide, one inch, and has eight tracks for data along its length. Between the third and the fourth track runs a line of smaller feed holes, from which the position of each row is measured. The rows are 2.54 mm apart, ten to the inch. The standard also allows narrower tape, 17.46 mm, because so much five-track equipment was still in use. The photograph above shows both kinds side by side.\n\nThe drawing on tape\n\nThe Zuse Graphomat Z64 plotter was not controlled directly by a computer. It read punched tape, first five-track and later eight-track: the computer punched the drawing as tape, and the tape was carried to the plotter. The Victoria and Albert Museum describes the Graphomat that Siemens bought on the initiative of Georg Nees as \"a drawing machine operated by computer-generated punched tape\".\n\nFrieder Nake wrote the software for the Graphomat at the Technische Hochschule Stuttgart before the machine arrived. \"So I wrote programs blindly on punched tape,\" he recalled, and took them to Zuse's headquarters in Bad Hersfeld. The plotter started, then stopped after five minutes, again and again. Nake knew the code well enough to pick up the confetti of punched-out paper from the floor and glue it into chosen holes in his tape. The drawing then ran.\n\nPrograms on tape\n\nTape also carried the programs themselves. The IBM programmer Sten Kallin (see the note on Astrid Sampe and Computer Art in Sweden) recalled an IBM 1620 he could use for whole nights, on which the FORTRAN compiler \"fanns inte i minnet utan den fanns på en hålremsa\": it was not in the memory but on a paper tape. He punched his program on tape. The computer read the first part of the compiler from tape and punched a new tape, then read the second part and his own tape, and punched out the finished program. In 1972 Tektronix sold the source code of its graphics software PLOT-10, for the Tektronix 4010 terminal, either on paper tape or on punched cards.\n\nNot every plotter artist used it. At the Météorologie Nationale in Paris, Manfred Mohr fed in his programs on punched cards, and his drawings went to the Benson plotter on magnetic tape. See the note on the Benson plotter and JAEV's text on plotter art."},
{"type": "note", "title": "The random walk", "url": "https://jaev.gallery/notes/random-walk/",
   "description": "A random walk is a path of steps in random directions. Karl Pearson named it in 1905. How far a walker gets, why it comes home, and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "random walk", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q856741"}], "mentions": [{"name": "Karl Pearson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q310794"}, {"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}],
   "sources": [{"title": "Heather M. Hill, “Random walkers illuminate a math problem”. Physics Today, 1 September 2019", "url": "https://physicstoday.aip.org/news/random-walkers-illuminate-a-math-problem"}, {"title": "Karl Pearson, “The Problem of the Random Walk”. Nature 72 (1865), p. 294, 1905 (bibliographic record)", "url": "https://doi.org/10.1038/072294b0"}, {"title": "“Random walk”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Random_walk"}, {"title": "Manfred Mohr, “From random walks (1969) to linear entanglement (2026)”. emohr.com", "url": "https://www.emohr.com/ManfredMohr_50YearCelebration_TimeLine.html"}],
   "related": {"notes":["diffusion-limited-aggregation","linear-congruential-generator","boids-craig-reynolds","perlin-noise"],"editorial":["manfred-mohr","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/random-walk-jaev.jpg", "alt": "Five tangled black lines on warm paper, each made of thousands of short straight steps, all starting from one small red circle in the middle and wandering outwards in different directions. A red dot marks where each one ends.", "credit": "Drawing by JAEV: five random walks of 3,000 steps of equal length, each in a random direction, from the same start (red circle); red dots mark the ends. CC BY 4.0."},
   "text": "A random walk is a path made of steps, each taken in a direction chosen by chance. The English mathematician Karl Pearson gave it its name in a letter to Nature in 1905, \"The Problem of the Random Walk\".\n\nPearson's problem\n\nPearson described a walker who starts at a point, walks a fixed distance of l yards in a straight line in a random direction, turns, walks another l yards in another random direction, and goes on like this n times. He wanted a formula for the probability that, after those n steps, the walker ends up at a distance r from the start. He had solved only the case of two steps.\n\nThe rule is the whole method: a starting point, a step length, and a source of random directions. In a computer the random directions come from a pseudo-random number generator, such as the linear congruential generator.\n\nHow far does it get?\n\nNot very far, and not in any one direction. The steps cancel each other out much of the time. On average the distance from the start grows like the square root of the number of steps: after 100 steps a walker is typically of the order of 10 step lengths away, after 10,000 steps of the order of 100. So a long walk spends most of its time near where it started and crosses its own path again and again, which is why a drawn walk looks like tangled knots joined by a few long runs.\n\nNew drawing\nLive sketch by JAEV: Pearson's walk of 5,000 steps of equal length, each in a random direction, drawn as it is taken. The dashed circle around the start has a radius of √n step lengths after n steps, the order of distance a walker typically gets. Code CC BY 4.0.\n\nIn art\n\nRandom walks were among Manfred Mohr's first programs. His own list of his work begins in 1969 with \"P-10 Random Walk drawings with alternating horizontal and vertical lines\" and \"P-16 - P-18 Random Walk drawings with horizontal and vertical lines\". He ran P-18 on a high-resolution light-beam plotter at Brookhaven National Laboratory.\n\nThe walk is also a working part inside other methods. In diffusion-limited aggregation thousands of particles take random walks until they touch a growing cluster, and the branching form comes entirely from where those walks tend to end. See also Generative Art."},
{"type": "note", "title": "Reaction–diffusion (Alan Turing, 1952)", "url": "https://jaev.gallery/notes/reaction-diffusion/",
   "description": "Two chemicals that react and spread can turn an even mixture into spots and stripes. Turing's 1952 idea, the Gray-Scott model and a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "reaction–diffusion system", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q901210"}], "mentions": [{"name": "Alan Turing", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q7251"}, {"name": "The Chemical Basis of Morphogenesis", "type": "CreativeWork", "sameAs": "https://www.wikidata.org/wiki/Q769913"}],
   "sources": [{"title": "A. M. Turing, “The chemical basis of morphogenesis”. Philosophical Transactions of the Royal Society of London B 237, no. 641 (14 August 1952), pp. 37–72 (scan)", "url": "https://www.mit.edu/~kardar/research/seminars/EPB/Turing.pdf"}, {"title": "Philip Ball, “Forging patterns and making waves from biology to geology: a commentary on Turing (1952)”. Philosophical Transactions of the Royal Society B 370 (2015), 20140218", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC4360114/"}, {"title": "John E. Pearson, “Complex Patterns in a Simple System”. Science 261 (1993); arXiv:patt-sol/9304003", "url": "https://arxiv.org/abs/patt-sol/9304003"}, {"title": "Karl Sims, “Reaction-Diffusion Tutorial”", "url": "https://www.karlsims.com/rd.html"}],
   "related": {"notes":["perlin-noise","l-systems-lindenmayer","line-hatching","voronoi-delaunay"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/reaction-diffusion-jaev.jpg", "alt": "A field of winding bands, rings and loops, each band filled with fine horizontal pen lines and outlined in black, on warm paper. Between the bands the paper is empty, so the pattern reads like a maze of hatched stripes.", "credit": "Drawing by JAEV: the Gray-Scott model (f = 0.055, k = 0.062, values from Karl Sims) on a grid of 201 × 126 cells after 5,000 steps, from 40 small seeds. Where chemical B is above 0.25 the paper is hatched; the edge is the contour B = 0.25. CC BY 4.0."},
   "text": "Reaction–diffusion is a way for patterns to appear by themselves: two or more chemicals react with each other and spread out at different speeds, and an even mixture breaks up into spots or stripes. Alan Turing proposed it in 1952 in \"The chemical basis of morphogenesis\", as a possible explanation of how a growing embryo gets its form. The same equations can be run step by step on a grid of numbers, as in the sketch below.\n\nTuring's idea\n\nThe paper was published on 14 August 1952. It opens: \"It is suggested that a system of chemical substances, called morphogens, reacting together and diffusing through a tissue, is adequate to account for the main phenomena of morphogenesis.\" Such a system can start out \"quite homogeneous\" and still develop a pattern, \"due to an instability of the homogeneous equilibrium, which is triggered off by random disturbances\". Turing suggested that \"a few particular cases\" could be treated \"with the aid of a digital computer\".\n\nGierer and Meinhardt independently described a theory of the same kind in 1972, with two substances: an activator and an inhibitor. In a commentary on Turing's paper, Philip Ball writes: \"Crucially, they must have different rates of diffusion, the inhibitor being faster\". Patterns like these were first reported in a real chemical reaction in 1990.\n\nThe Gray-Scott model\n\nA model often used for pictures is the one by Gray and Scott, which John E. Pearson explored with computer simulations in Science in 1993. It has two reactions: one molecule of U and two of V make three of V, and V turns into an inert product. U is fed in from outside. In Karl Sims's tutorial the chemicals are called A and B, and every cell of a grid holds one number for each. At each step:\n\nDiffusion. Each chemical spreads to the neighbouring cells, A twice as fast as B (rates 1.0 and 0.5).\n\nReaction. Where there is B, two B's turn one A into B: B grows by using A as food.\n\nFeed and kill. A is added everywhere at a feed rate f (for example 0.055); B is removed at a kill rate k (for example 0.062).\n\nOther values of f and k give other patterns. Pearson found regular hexagons, irregular patterns that stay still, patterns that never settle, and spots that grow until they \"divide in two\". Strictly, these are not Turing's patterns: Pearson notes that with his ratio of diffusion rates \"there are no stable Turing patterns\". They arise instead when the even state is disturbed hard enough.\n\nNew drawing\nLive sketch by JAEV: the Gray-Scott model as described by Karl Sims (dA = 1.0, dB = 0.5, f = 0.055, k = 0.062) on a grid of 180 × 120 cells that wraps at the edges, run for 9,000 steps from a few random spots of B. Cells with more than 0.25 of B are inked. Each new drawing starts from new spots. Code CC BY 4.0.\n\nIn living things\n\nBall describes how the idea has been applied to animal markings: the morphogens would switch on the genetic pathways that make pigments, such as melanin in the skin of mammals. He also notes a limit: in zebrafish the stripes come from direct contact between cells, not from diffusing chemicals. For other ways that rules and chance make surfaces, see Perlin noise and Generative art."},
{"type": "note", "title": "The RGB colour cube", "url": "https://jaev.gallery/notes/rgb-colour-cube/",
   "description": "How a screen mixes red, green and blue light, why that makes a cube of 16,777,216 colours, and how a printed colour cube in ink differs.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "RGB color model", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q166194"}], "mentions": [{"name": "CMYK color model", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q166432"}, {"name": "Mikael Jern", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63869789"}, {"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "Lund University", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q218506"}],
   "sources": [{"title": "“RGB color model”. Wikipedia", "url": "https://en.wikipedia.org/wiki/RGB_color_model"}, {"title": "“Automatic Colour Cubes”, Olof Broström. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/automatic-colour-cubes/"}, {"title": "Anna Orrghen, Från matematikmaskin till IT. Fokusgrupp: Media. Slutrapport. Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2016/11/slutrapport-media-anna-orrghen.pdf"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}],
   "related": {"notes":["color-program-mikael-jern","hertz-ink-jet-colour-plotter","beck-and-jung","sha-256-as-random-source"],"editorial":["the-colour-cubes","sol-lewitt"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/rgb-colour-cube-jaev.jpg", "alt": "A cube seen corner-on, built of 12 by 12 by 12 small cubes in flat colours: blue at the top corner, cyan and green down the left side, magenta and red down the right, yellow at the bottom. A block is cut out of the near corner, where white would be, showing paler colours and greys inside.", "credit": "Drawing by JAEV: the RGB colour cube with 12 steps along each edge instead of 256, so 1,728 of the 16,777,216 colours, with a block cut out of the white corner to show the inside. CC BY 4.0."},
   "text": "The RGB colour cube draws every colour a screen can show as a point inside a cube. Its three edges measure the screen's three lights, red, green and blue. Black sits in one corner and white in the opposite one.\n\nThree lights, three axes\n\nEach pixel on a screen is made of three small lights. RGB is an additive colour model: light is added to light, so the more of each, the brighter the result. If each light gets a value from nothing to full, any colour the pixel can show is three numbers, and three numbers are a position in space. Put red on one axis, green on the second and blue on the third, and all the possible colours fill a cube.\n\nThe corner where all three values are zero is black; the opposite corner, all three at full, is white. The diagonal between them runs through the greys, where the three values are equal. Three corners hold red, green and blue on their own. The last three hold two full lights each: yellow, cyan and magenta, each the complement of the light that is missing (cyan of red, magenta of green, yellow of blue).\n\n16,777,216 colours\n\nModern systems usually store each of the three values in 8 bits, giving 256 levels, from 0 to 255. The cube then has 256 steps along each edge and 256 × 256 × 256 = 16,777,216 points: the \"16.7 million colours\" of a screen with 24 bits per pixel.\n\nNew drawing\nSketch by JAEV of the RGB colour cube with 12 steps along each edge instead of 256, so 1,728 of the 16,777,216 colours. Each new drawing cuts a different block out of the white corner to show the inside; drag to turn the cube. Code CC BY 4.0.\n\nThe same cube in ink\n\nPrint works the other way round. Ink takes light away from white paper, so a printed colour cube is built from the complements, cyan, magenta and yellow, with unprinted paper in the corner where no ink is used.\n\nIn Lund in the 1970s, the mathematician Mikael Jern wrote software for Lund University's ink-jet colour plotter, built by Hellmuth Hertz, that drew such a cube: 17 × 17 × 17 small cubes. The plotter printed three inks on top of each other, and Jern made lighter and darker tones with a matrix of 4 × 4 dots. His cube had 4,913 colours where a screen's has more than sixteen million. How it was made, and who later signed it, is told in JAEV's editorial The colour cubes and in the notes on the colour plotter and Jern's COLOR program.\n\nWhere to see it\n\nOlof Broström's Automatic Colour Cubes, 122 works made one a day on JAEV's server from 10 October 2026, starts from Jern's ink cube rather than the screen's. Each work reduces the cube to its outer shell and opens it along the edges that one of Sol LeWitt's Incomplete Open Cubes leaves out, so the inside of the colour range becomes visible. The works exist as print files in the three inks plus black; the images on the exhibition page are, in its words, \"translations for the screen\"."},
{"type": "note", "title": "Roland DXY plotters", "url": "https://jaev.gallery/notes/roland-dxy-plotters/",
   "description": "Roland DG's DXY desktop pen plotters of the 1980s: how they work, their step size, speed and pens, the two command languages, and using one today.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Roland DXY", "type": "Thing", "sameAs": null}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Roland DG", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q2162714"}, {"name": "HP-GL", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1422842"}, {"name": "Paul Rickards", "type": "Person", "sameAs": null}, {"name": "vpype", "type": "Thing", "sameAs": null}],
   "sources": [{"title": "“History”. Roland DGA", "url": "https://image.rolanddga.com/en/about-us/history"}, {"title": "Paul Rickards, “Pen Plotter” posts. biosrhythm.com", "url": "https://biosrhythm.com/?cat=118"}, {"title": "Roland DXY-880 X-Y Plotter Operation Manual. Roland DG, via the Internet Archive", "url": "https://archive.org/details/RolandDXY880PlotterOperationManual"}, {"title": "Roland DXY-990 Operation Manual. Roland DG, via the Internet Archive", "url": "https://archive.org/details/roland-dxy-990"}, {"title": "Roland DXY-1300/1200/1100 Command Reference Manual. Roland DG, via the Internet Archive", "url": "https://archive.org/details/rolanddxy130012001100commandreferencemanualaf"}, {"title": "vpype_config.toml (built-in plotter profiles). vpype, GitHub", "url": "https://github.com/abey79/vpype/blob/master/vpype/vpype_config.toml"}],
   "related": {"notes":["hp-7475a","hp-gl","plotter-pens","vpype","axidraw"],"editorial":["plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/roland-dxy-plotters-jaev.jpg", "alt": "A line drawing of a flat plotter seen from above: a rectangle for the body, a dashed rectangle for the plotting area, and a long narrow arm crossing it with a small square pen carriage in the middle. Red double arrows show the arm moving left and right and the carriage moving up and down along it. Left of the arm, a column of horizontal lines already drawn. On the right, a staircase line labelled one step = 0.05 mm, and a row of eight small circles labelled eight pens.", "credit": "Diagram by JAEV after the DXY-880 operation manual: body 533 × 430 mm and plotting area 380 × 270 mm to scale. The arm and the pen carriage move (red arrows), the paper does not. Pen clips and buttons are left out. CC BY 4.0."},
   "text": "The Roland DXY plotters are desktop pen plotters made by Roland DG of Japan from 1982, when the first model, the DXY-100, came out \"to produce architectural drawings and schematics\". The DXY-800 for A3 paper followed in 1983. Some are still in use: the plotter artist Paul Rickards draws on a DXY 1150.\n\nThe company\n\nRoland DG began in Osaka in 1981 as AMDEK Corporation, a subsidiary of the musical instrument maker Roland. It took the name Roland DG in 1983; DG stands for Digital Group.\n\nHow they work\n\nA DXY is a flatbed plotter of the gantry type: the paper lies still, an arm moves across it, and the pen carriage moves along the arm. The machine sits flat on a table or tilted up on a stand.\n\nThe DXY-880's manual gives a plotting area of 380 × 270 mm, a little more than A4 but less than A3, a speed of 200 mm a second in all directions, and a smallest step of 0.05 mm. It holds eight pens, connects to a computer by a parallel or a serial (RS-232C) cable, and weighs 4.3 kg. The DXY-990 draws at up to 300 mm a second. It holds the paper down with static electricity, and a \"soft landing\" mechanism lowers the pen gently enough to use ink drafting pens.\n\nTwo languages\n\nThe DXY plotters understand two sets of commands, chosen with DIP switches. The DXY commands are one letter each and simple to send from BASIC. RD-GL, Roland DG Graphic Language, has two-letter commands. The DXY-990's manual also advertises compatibility with the HP-GL of Hewlett-Packard's 7470 and 7475A.\n\nPens\n\nRoland sold its own pens for the DXY: water-based fibre-tip pens of 0.3 and 0.6 mm, pens for overhead film, ballpoint pens, ink pens and ceramic-tipped pens. The ceramic tip keeps \"a precise line width\" until the ink runs out. Holders let the DXY-880 use ordinary fibre-tip pens, at most 9.5 mm thick where they fit and no heavier than 7 g. See plotter pens.\n\nToday\n\nPaul Rickards prefers the gantry type, \"typically made by Roland\", and in 2021 showed his DXY 1150 drawing a generative circle design on a 5.25-inch floppy disk. The command-line tool vpype has a built-in profile for the \"Roland DXY 1xxx\" series: eight pens, a unit of 0.025 mm, and the expanded plot area set with the switches. The longer history is in JAEV's text on plotter art."},
{"type": "note", "title": "Roman Verostko and the Algorists (1995)", "url": "https://jaev.gallery/notes/algorists-verostko/",
   "description": "In 1995 Roman Verostko and Jean-Pierre Hébert named artists who use their own algorithms algorists. The definition, and Verostko's brush plotter.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Roman Verostko", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q7362232"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Jean-Pierre Hébert", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6169904"}, {"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}, {"name": "Harold Cohen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92723"}, {"name": "Charles Csuri", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5076580"}, {"name": "Vera Molnár", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1658002"}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}],
   "sources": [{"title": "Roman Verostko, “The Algorists”. verostko.com", "url": "https://www.verostko.com/algorist.html"}, {"title": "“Roman Verostko”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Roman_Verostko"}, {"title": "Roman Verostko, résumé. verostko.com", "url": "https://www.verostko.com/resume-all.html"}, {"title": "Roman Verostko, “Epigenetic Painting: Software as Genotype” (FISEA, Utrecht, 1988). verostko.com", "url": "https://www.verostko.com/epigenet.html"}],
   "related": {"notes":["manfred-mohr-cubic-limit","aaron-rules","hp-gl","plotter-pens"],"editorial":["generative-art","plotter-art","the-rule-is-the-work","harold-cohen","vera-molnar"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/algorists-verostko-jaev.jpg", "alt": "Two lines of code in a typewriter-style font on warm paper. The first, in black, reads: if (creation && object of art && algorithm && one's own algorithm) {include * an algorist *}, with the words one's own algorithm underlined in red. The second, in grey, is the opposite case, ending exclude * not an algorist *.", "credit": "Jean-Pierre Hébert's definition of an algorist (1995), as quoted by Roman Verostko, set by JAEV with one statement per line (the card breaks the lines further). Typography CC BY 4.0."},
   "text": "The algorists are artists who make art with algorithms they write themselves. The name was adopted in 1995 by a small group around the American painter Roman Verostko (1929–2024) and the artist Jean-Pierre Hébert (1939–2021), and Hébert wrote its definition as a piece of code.\n\nHow the name came about\n\nAt the SIGGRAPH conference in Los Angeles in 1995, the Belgian artist Peter Beyls chaired a panel called \"Artists and Algorithms\", with Hébert, Brian Evans, Stephen Bell, Ken Musgrave and Verostko. After the conference Hébert, Musgrave and Verostko wrote to each other looking for a name for what they did. In Verostko's account, \"It was Jean Pierre who proposed using the term 'algorist'\".\n\nThe word itself is old. An algorist was someone who calculates with algorisms, the step-by-step methods of arithmetic. Verostko points out that many of the group had been working this way for about 25 years before 1995, so the name gave an identity to a practice that already existed.\n\nThe definition\n\nHébert noted that algorists \"ought to be defined with an algorithm\", and wrote one. Verostko quotes it \"formatted precisely as received\":\n\nif (creation && object of art && algorithm && one's own algorithm) {include * an algorist *} elseif (!creation || !object of art || !algorithm || !one's own algorithm) {exclude * not an algorist *}\n\nRead as plain English: if something is a creation, an object of art, made with an algorithm, and the algorithm is the artist's own, the maker is an algorist; if any one of the four is missing, not. \"It is the inclusion of one's own algorithms that makes the difference,\" Verostko writes. A computer is not required: he counts Channa Horwitz, who carried out her number-based rules entirely by hand, as an algorist. JAEV's The rule is the work draws the same line between writing a system yourself and prompting someone else's.\n\nIn 1996 Hébert put up web pages on the algorists that named an informal group, among them Harold Cohen, Charles Csuri, Hans Dehlinger, Helaman Ferguson, Manfred Mohr, Vera Molnár and Mark Wilson, \"and others\". Cohen's program is described in AARON's rules.\n\nVerostko's brush on the plotter\n\nVerostko was a Benedictine monk at Saint Vincent Archabbey in Pennsylvania from 1952 to 1968, and a painter. After leaving the order he taught at the Minneapolis College of Art and Design from 1968 to 1994.\n\nHe then wrote software that drew on paper, called Hodos, Greek for \"path\". It drove a 14-pen plotter, and in 1987 he added routines \"to drive paint brushes mounted on a pen plotter drawing arm\". In a paper from 1988 he calls the software a genotype, \"the code for 'how to make the work'\", which can make a family of works, each one unique. He found that Hodos produced paintings with \"an uncanny resemblance\" to what he had painted by hand before computers.\n\nHow plotters are told where to go is explained in HP-GL; the wider history is in JAEV's Plotter Art and Generative Art."},
{"type": "note", "title": "Rörelse i konsten (Moderna Museet, 1961)", "url": "https://jaev.gallery/notes/rorelse-i-konsten-1961/",
   "description": "Rörelse i konsten (Movement in Art), Moderna Museet 1961: 233 works that moved, a drawing machine by Tinguely, and a tour of 143,000 visitors.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Rörelse i konsten", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q18753217"}, {"name": "kinetic art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q466521"}], "mentions": [{"name": "Moderna Museet", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1274511"}, {"name": "Stedelijk Museum Amsterdam", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q924335"}, {"name": "Louisiana Museum of Modern Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1410617"}, {"name": "Pontus Hultén", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q268653"}, {"name": "Daniel Spoerri", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q123487"}, {"name": "Jean Tinguely", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q163938"}, {"name": "Alexander Calder", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q151580"}, {"name": "Nicolas Schöffer", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q603870"}, {"name": "Per Olof Ultvedt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q827276"}, {"name": "William Grey Walter", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1359845"}, {"name": "Billy Klüver", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4912866"}],
   "sources": [{"title": "Anna Lundström, “Rörelse i konsten. En utställnings lager”, in Pontus Hultén och Moderna Museet. De formativa åren, Moderna Museet, Stockholm, 2017 (English edition: “Movement in Art. The layers of an exhibition”, Koenig Books, London)", "url": "https://www.modernamuseet.se/stockholm/wp-content/uploads/sites/3/2022/11/ph__sv_lundstrom.pdf"}, {"title": "“50 years since Rörelse i konsten (Movement in art)”. Moderna Museet, 14 June 2011", "url": "https://www.modernamuseet.se/en/news/50-years-since-rorelse-konsten-movement-art/"}, {"title": "Jean Tinguely, Méta-Matic nr 17, 1959 (NMSK 1895). Moderna Museet, Stockholm", "url": "https://sis.modernamuseet.se/en/objects/details/4591"}, {"title": "“Billy Klüver”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Billy_Kl%C3%BCver"}, {"title": "Jøran Rudi, “Unpacking the Musical and Technical Innovation of Knut Wiggen”. Organised Sound 23 (2), 2018, pp. 195–207", "url": "http://www.knut-wiggen.com/Texts/Rudi_OS_23.3.pdf"}],
   "related": {"notes":["jean-tinguely-meta-matics","cybernetic-serendipity","ems-elektronmusikstudion","datasaab-and-swedish-computer-art"],"editorial":["computer-art-in-sweden","plotter-art","ture-sjolander"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/rorelse-i-konsten-1961-jaev.jpg", "alt": "A timeline of March to October 1961 with three boxes filled with thin vertical lines: Bewogen Beweging in Amsterdam, 10 March to 17 April, 50,000 visitors; Rörelse i konsten in Stockholm, in red, 17 May to 3 September, 70,000 visitors; Bevægelser i kunsten in Humlebæk, 22 September to 29 October, 23,000 visitors.", "credit": "Diagram by JAEV: the exhibition's three venues in 1961. Each box is as long as the show ran, and holds one line per 1,000 visitors, so denser boxes had more visitors per day. Dates and numbers from Anna Lundström (2017). CC BY 4.0."},
   "text": "Rörelse i konsten (Movement in Art) was an exhibition of art that moves, shown at Moderna Museet in Stockholm from 17 May to 3 September 1961. It was the first large exhibition of the museum's director Pontus Hultén, produced with the artist Daniel Spoerri, and it was also shown in Amsterdam and in Denmark.\n\nWhat was shown\n\nThe exhibition had 233 works. The historian Anna Lundström counts 85 artists; Moderna Museet's own anniversary page says 83, and only eight of the works were by women. The idea was that movement was the key to all art of the 20th century, from the Futurists' paintings of motion to machines that actually move.\n\nJust inside the entrance stood Nicolas Schöffer's Cysp I (1956), a 260 cm sculpture that moved across the floor when a button was pressed. The first hall held 32 mobiles by Alexander Calder. The second, darker hall held 27 machines by Jean Tinguely and large wooden constructions by the Swedish artist Per Olof Ultvedt. Visitors could set the mobiles turning and were expected to start Tinguely's machines.\n\nA machine that draws\n\nAmong Tinguely's works was Méta-Matic No. 17 (1959). In Moderna Museet's description it \"dances, makes noises and incessantly spits out ink drawings\", while the exhaust from its petrol engine slowly fills a balloon until it bursts. It draws with no hand on the pen; plotter art later gave the same job to a computer. The machines are described in Tinguely's Méta-Matics.\n\nObjects that were not art\n\nHultén also wanted what he called the \"periphery\" of moving art: old automata, mechanical toys, fireworks, racing cars. In the end only a car was shown, a Bugatti behind a rope. He wrote to W. Grey Walter at the Neurological Institute in Bristol to ask about borrowing the institute's \"robot turtles\", so that they could be shown as works of art. Lundström does not say whether they came. The catalogue reprinted \"Garden Party\", a text by the engineer Billy Klüver, who grew up in Sweden and worked at Bell Labs.\n\nThree venues\n\nHultén wanted the exhibition to open in Stockholm, but it opened at the Stedelijk Museum in Amsterdam as Bewogen Beweging, against his protests. Spoerri had argued that in an established museum no one would question whether the objects were art. A letter from Louisiana's director gives the visitor numbers: 50,000 in Amsterdam (10 March–17 April), 70,000 in Stockholm and 23,000 at Louisiana in Humlebæk (22 September–29 October), where the title was Bevægelser i kunsten.\n\nIn the 1960s, under its chairman Knut Wiggen, the Stockholm music society Fylkingen also moved its concerts to Moderna Museet. The Stockholm composers and engineers who worked with computers in those years are described in Computer Art in Sweden and in the note on EMS, the electronic music studio."},
{"type": "note", "title": "Schotter (Georg Nees, 1968)", "url": "https://jaev.gallery/notes/georg-nees-schotter/",
   "description": "Schotter (Gravel) by Georg Nees: 264 squares whose random shift and rotation grow with a single counter. The rule, the random numbers and a live sketch.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "Victoria and Albert Museum", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q213322"}, {"name": "ALGOL 60", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1209759"}],
   "sources": [{"title": "Georg Nees, Schotter, 1968–1970. Lithograph on paper. Victoria and Albert Museum, London, E.217-2008", "url": "https://collections.vam.ac.uk/item/O221321/"}, {"title": "Zellyn Hunter, “Schotter – Georg Nees – Part 1”, 2024", "url": "https://zellyn.com/2024/06/schotter-1/"}, {"title": "Zellyn Hunter, “Schotter – Georg Nees – Part 2”, 2024", "url": "https://zellyn.com/2024/06/schotter-2/"}, {"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal, Spring 2009", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}, {"title": "Georg Nees, Generative Computergraphik. Doctoral dissertation, 1969, with the 2006 reprint. Internet Archive", "url": "https://archive.org/details/generative_computergraphik"}],
   "related": {"notes":["generative-computergrafik-stuttgart-1965","zuse-graphomat-z64","vera-molnar-interruptions","frieder-nake-hommage-a-paul-klee"],"editorial":["georg-nees","generative-art","plotter-art"],"exhibitions":["difficulty"]},
   "image": {"url": "https://jaev.gallery/assets/notes/georg-nees-schotter-jaev.jpg", "alt": "Twelve squares across and twenty-two down, drawn in thin black lines on warm paper. The top rows stand straight in a grid; row by row the squares shift and turn more, until at the bottom they lie scattered and overlapping.", "credit": "Reconstruction by JAEV after the method of Georg Nees's Schotter (1968): 12 × 22 squares whose shift and rotation grow with the counter I, drawn with Nees's multiply-by-5 generator and seeds of JAEV's own, so not the 1968 sheet. Not the original. CC BY 4.0."},
   "text": "Schotter (German for gravel) is a plotter drawing by Georg Nees, made in 1968. It shows a grid of squares that stand in neat rows at the top and fall into disorder towards the bottom. The Victoria and Albert Museum in London holds a lithograph of it, printed 1968–70, 28 × 21.8 cm, and describes Nees's subject as \"the relationship between order and disorder in picture composition\".\n\nHow it works\n\nThe program draws 264 squares, twelve across and twenty-two down, each with sides of 10 units on a grid with 10-unit spacing. Every square gets three random numbers: a shift sideways, a shift up or down, and an angle. What makes the picture is that the allowed range of those numbers is not fixed. It depends on a counter, I, that goes up by one for every square drawn, from 0 to 263.\n\nShift. Each square may move up to 5 × I / 264 units from its place in the grid. For the first square that is 0; for the last it is almost 5, half a square.\n\nRotation. The angle is chosen between π/4 × (1 − I/264) and π/4 × (1 + I/264). A square drawn at π/4 from its corner stands straight; the last squares can turn by up to 45 degrees either way.\n\nSo one number, the count of squares drawn so far, controls all the variation. That is why the picture can be read. The rule is visible in the image, and chance grows under it row by row.\n\nThe random numbers\n\nNees wrote his programs in ALGOL 60 at Siemens in Erlangen, and the drawings were made by a Zuse Graphomat Z64, a flatbed plotter that drew from a paper tape calculated beforehand. His dissertation, Generative Computergraphik (1969), describes a generator that multiplies the previous number by 5 and keeps only the remainder after dividing by 2³¹. Schotter uses two such generators, one for the shifts and one for the angles, each started from its own number, the seed.\n\nBecause the generator is exact arithmetic, the same seeds always give the same drawing. In 2024 the programmer Zellyn Hunter searched about a billion seeds against the printed sheet and found the pair that reproduces it: 1922110153 for the shifts and 1769133315 for the angles.\n\nLive sketch\n\nNew drawing\nReconstruction by JAEV after the method of Schotter: 12 × 22 squares, shift up to 5 × I/264 units, angle π/4 ± π/4 × I/264, with Nees's multiply-by-5 generator as read by Zellyn Hunter. Each new drawing takes two new random seeds, so it is never the 1968 sheet; the order of the random calls is JAEV's choice. Code CC BY 4.0.\n\nWhere to see it\n\nThe V&A's lithograph is listed in its online collection. Hunter's two articles, part 1 and part 2, show the ALGOL listing and a Python translation.\n\nThe same idea, a fixed rule whose output is decided by numbers from outside the artist's hand, runs through Difficulty, a drawing a day by Olof Broström at JAEV, where the number of lines and their angle come from the first block of a public proof-of-work ledger added after midnight UTC."},
{"type": "note", "title": "Senster (Edward Ihnatowicz, 1970)", "url": "https://jaev.gallery/notes/edward-ihnatowicz-senster/",
   "description": "The Senster, Edward Ihnatowicz's hydraulic sculpture for Philips's Evoluon (1970–74), turned toward sounds and shied from noise. How it worked.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Senster", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1231464"}, {"name": "Edward Ihnatowicz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5343589"}], "mentions": [{"name": "Philips", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q170416"}, {"name": "Evoluon", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q23212"}, {"name": "AGH University of Krakow", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q414245"}, {"name": "robotic art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2864727"}],
   "sources": [{"title": "“Cybernetic sculpture – The Senster”. Alex Zivanovic, senster.com", "url": "https://www.senster.com/ihnatowicz/senster/index.htm"}, {"title": "“Edward Ihnatowicz biography”. senster.com", "url": "https://www.senster.com/ihnatowicz/biography.htm"}, {"title": "“SAM – Sound Activated Mobile”. senster.com", "url": "https://www.senster.com/ihnatowicz/SAM/sam.htm"}, {"title": "“Technical Info about the Senster: The Mechanical Structure”. senster.com", "url": "https://www.senster.com/ihnatowicz/senster/sensterstructure/index.htm"}, {"title": "“Technical Info about the Senster: The Doppler Radar System”. senster.com", "url": "https://www.senster.com/ihnatowicz/senster/sensterradar/index.htm"}, {"title": "“Technical Info about the Senster: The Computer Hardware and Software”. senster.com", "url": "https://www.senster.com/ihnatowicz/senster/senstercomputer/index.htm"}, {"title": "“The final fate of the Senster”. senster.com", "url": "https://www.senster.com/ihnatowicz/senster/sensterfinalfate/index.htm"}, {"title": "“Re:SENSTER”. AGH University of Krakow", "url": "http://senster.agh.edu.pl/"}],
   "related": {"notes":["cybernetic-serendipity","punched-paper-tape","desmond-paul-henry-drawing-machines"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/edward-ihnatowicz-senster-jaev.jpg", "alt": "A line drawing in side view: a jointed arm of three straight segments rises from a trapezoid base on the floor, with a short piston beside each segment and small circles at the joints. At the end, a box-shaped head with four black dots for microphones and two small horns. To the right, a red dot gives off red sound waves, and a dashed red arrow shows the head turning toward it. Grey labels: hydraulic pistons, steel tube, microphones and radar, sound.", "credit": "Diagram by JAEV of how the Senster worked: a jointed steel arm moved by hydraulic pistons, with microphones and radar on its head, turning toward a sound. Simplified; not a drawing of the sculpture. CC BY 4.0."},
   "text": "The Senster was a hydraulic sculpture by Edward Ihnatowicz, over four metres long, that stood in the Evoluon in Eindhoven, the permanent showplace of the electronics company Philips, from 1970 to 1974. It turned toward the sounds people made and shied away from sudden movements and loud noises. It was controlled by a computer; the account on senster.com calls it, \"as far as I know\", the first robotic sculpture that was.\n\nThe artist\n\nIhnatowicz was born in Poland in 1926, came to Britain in 1943 and studied at the Ruskin School of Art in Oxford. He made furniture and sculpture before he turned to moving machines. His first, SAM (Sound Activated Mobile), was shown in Cybernetic Serendipity in London in 1968: a column of cast aluminium vertebrae with four microphones on top, which leaned and twisted toward a quiet, steady sound. Philips then commissioned something much larger.\n\nThe machine\n\nThe Senster was welded from steel tubing by a technician at University College London, working from Ihnatowicz's rough sketches; there were no proper engineering drawings. It went to Eindhoven in July 1970. Hydraulic pistons moved its joints.\n\nIt had two kinds of senses, both on its head:\n\nMicrophones, which picked out the direction of the predominant sound. The head turned toward it first; if the sound went on, the rest of the body followed.\n\nTwo Doppler radar units, which detected people moving toward it or away from it.\n\nA Philips P9201 computer, with 8K of core memory and a punched paper tape unit, read the sensors and drove the pistons. Ihnatowicz wrote its program himself.\n\nBehaviour, not looks\n\nThe rules were fairly simple: go toward a sound, retreat from a shock. The hall's echoes and the unpredictable public made the movements look far more sophisticated than they were, and the account on senster.com concludes that the effect on visitors came from that behaviour, not from the Senster's appearance. Art in which simple rules, not a fixed form, produce what is seen is the subject of JAEV's Generative Art.\n\nAfterwards\n\nThe Senster was dismantled in 1974. Its electronics were given away; the steel structure went to an engineering company, which set it up outdoors beside its building. In April 2017 the AGH University of Krakow bought it, and from 4 October 2018 the restored sculpture could be seen in Kraków. It now responds only to sound. Ihnatowicz worked as a research assistant in mechanical engineering at University College London from 1971 and died in 1988."},
{"type": "note", "title": "SHA-256 as a source of chance", "url": "https://jaev.gallery/notes/sha-256-as-random-source/",
   "description": "How a hash function such as SHA-256 turns any text into a fixed 256-bit number that looks random, and why generative artists use it to make choices.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "SHA-256", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q110651361"}, {"name": "cryptographic hash function", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q477202"}], "mentions": [{"name": "SHA-2", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1968605"}, {"name": "National Institute of Standards and Technology", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q176691"}],
   "sources": [{"title": "“SHA-2”. Wikipedia", "url": "https://en.wikipedia.org/wiki/SHA-2"}, {"title": "FIPS 180-4, Secure Hash Standard (SHS). National Institute of Standards and Technology, August 2015", "url": "https://csrc.nist.gov/pubs/fips/180-4/upd1/final"}, {"title": "“SubtleCrypto: digest() method”. MDN Web Docs, Mozilla", "url": "https://developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto/digest"}, {"title": "“Avalanche effect”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Avalanche_effect"}, {"title": "“1. Building Your Project”. Art Blocks documentation", "url": "https://docs.artblocks.io/creator-onboarding/artists/1-building-your-project"}, {"title": "“Content”, JAEV. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/content/"}, {"title": "“Hôtel de Ville, Limoges × ImmunityBio −8.3% × Alberta separation referendum”, Content, 19 October 2026. JAEV, Lund", "url": "https://jaev.gallery/exhibitions/content/2026-10-19-hotel-de-ville-limoges-immunitybio-alberta-separation-referendum/"}],
   "related": {"notes":["bitcoin-difficulty","perlin-noise","ten-print-maze","rgb-colour-cube"],"editorial":["generative-art","the-rule-is-the-work"],"exhibitions":["content"]},
   "image": {"url": "https://jaev.gallery/assets/notes/sha-256-as-random-source-jaev.jpg", "alt": "Three grids of 16 by 16 small squares. The first two show the 256 bits of the SHA-256 hashes of the texts JAEV and JAEW, black for 1 and empty for 0, with the hashes in hexadecimal printed below. The third, in red, marks the 131 bits that differ between them.", "credit": "Diagram by JAEV: two spellings, two hashes. The first grid is the SHA-256 hash of the word JAEV, the second of JAEW, each as 256 squares (black for 1, empty for 0). Only the last letter differs, yet 131 of the 256 squares change: they are red in the third grid. CC BY 4.0."},
   "text": "SHA-256 is a hash function: it turns any text or file into a number 256 bits long. It belongs to the SHA-2 family, designed by the United States National Security Agency and first published in 2001. It was made for security, but its output looks random while being completely fixed by its input, so artists use it as a source of chance that can be repeated.\n\nWhat the function does\n\nThe current standard, FIPS 180-4 from the US National Institute of Standards and Technology, describes hash algorithms that produce a \"digest\" of a message, so that anyone can check whether the message has been changed since. Whatever goes in, a single word or a whole film, SHA-256 gives back 256 bits, usually written as 64 hexadecimal digits.\n\nTwo properties make it useful outside cryptography:\n\nThe same input always gives the same output. There is no hidden state, and no clock is involved.\n\nA small change gives a completely different output. If one bit of the input is flipped, about half of the output bits change: the avalanche effect, a term the cryptographer Horst Feistel first used in 1973.\n\nTogether this means the hash behaves like a dice roll that can be rolled again with exactly the same result.\n\nFrom hash to choices\n\nA generative program reads the 256 bits as 32 numbers from 0 to 255 (one per byte) and lets each one decide something: how many shapes, which kind, which colour, where. The sketch below does that with the text you type.\n\nNew drawing\nSketch by JAEV: the SHA-256 hash of the text, computed in your browser with crypto.subtle.digest, chooses the number of shapes, their kind, colour, symmetry and placement. \"New drawing\" changes one letter and counts how many of the 256 bits change. A simplified illustration of the method, not the program behind any JAEV work. Code CC BY 4.0.\n\nOn the platform Art Blocks, each work's script is given a 32-byte hash as its seed, and the documentation tells artists: \"This is your only randomness source.\" The same hash must always produce the same image. SHA-256 is also the function behind proof of work in Bitcoin, explained in the note on Bitcoin's difficulty.\n\nWhere to see it\n\nJAEV's own work Content makes one image a day from a short text recording what the world paid most attention to the day before. The text is turned into a fingerprint, its SHA-256 hash, and the hash makes one choice in each of seven parts of the work: composition, shape, edge, colours, movement, symmetry and layers. The same text always gives the same work. Each work's page prints the hash and the seven choices it made."},
{"type": "note", "title": "Sol LeWitt's instructions as algorithms (Wall Drawing 86)", "url": "https://jaev.gallery/notes/sol-lewitt-instructions-as-algorithms/",
   "description": "Sol LeWitt's Wall Drawing 86 (1971) is one sentence: ten thousand lines covering the wall evenly. What a program must decide to carry it out.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}], "mentions": [{"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}, {"name": "Massachusetts Museum of Contemporary Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q588474"}],
   "sources": [{"title": "“Wall Drawing 86”, Sol LeWitt, June 1971. MASS MoCA, North Adams", "url": "https://massmoca.org/event/walldrawing86/"}, {"title": "Sol LeWitt, “Paragraphs on Conceptual Art”, Artforum, June 1967", "url": "https://monoskop.org/images/3/3d/LeWitt_Sol_1967_1999_Paragraphs_on_Conceptual_Art.pdf"}, {"title": "Anna Lovatt, “Ideas in Transmission: LeWitt’s Wall Drawings and the Question of Medium”, Tate Papers no. 14, Tate, London, 2010", "url": "https://www.tate.org.uk/research/tate-papers/14/ideas-in-transmission-lewitt-wall-drawings-and-the-question-of-medium"}, {"title": "“Casey Reas: {Software} Structures”. Whitney Museum of American Art, New York", "url": "https://whitney.org/exhibitions/software-structures"}, {"title": "“Sol LeWitt: Cubic Forms”. Paula Cooper Gallery, New York", "url": "https://www.paulacoopergallery.com/exhibitions/sol-lewitt13"}],
   "related": {"notes":["aaron-rules","ten-print-maze","georg-nees-schotter","vera-molnar-interruptions"],"editorial":["sol-lewitt","casey-reas","generative-art","the-rule-is-the-work"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/sol-lewitt-wall-drawing-86-jaev.jpg", "alt": "The outline of a wide wall, evenly covered with ten thousand short, thin straight lines in every direction, which together make an even grey.", "credit": "Reconstruction by JAEV after the instruction for Sol LeWitt's Wall Drawing 86 (1971): ten thousand lines about 25 cm long, covering a wall of 4 × 2.5 m evenly. The wall, the line lengths, the grid used for evenly and the angles are JAEV's choices, not the work. CC BY 4.0."},
   "text": "Sol LeWitt's wall drawings exist as written instructions that other people carry out on a wall. Read as a procedure, an instruction is close to an algorithm: a description precise enough that someone other than the author can produce the work by following it. This note takes one instruction, Wall Drawing 86 (1971), turns it into code, and lists the decisions the code has to make.\n\nThe instruction\n\nThe Massachusetts Museum of Contemporary Art (MASS MoCA), where the drawing is installed, gives the full instruction for Wall Drawing 86, dated June 1971:\n\nTen thousand lines about 10 inches (25 cm) long, covering the wall evenly.\n\nIt is drawn in black pencil. The museum adds that \"other aspects of the lines (their orientation, how often they intersect each other, etc.) are decided by the draftsman\", and that \"the even distribution is conditioned by the dimensions of the wall.\"\n\nWhy it is close to an algorithm\n\nLeWitt described the principle in \"Paragraphs on Conceptual Art\" in 1967: \"The idea becomes a machine that makes the art.\" He installed his first wall drawing himself. From 1969 he asked friends, curators and collectors to install them from his instructions, and later he employed a team of technicians.\n\nWall Drawing 86 has a single step, repeated ten thousand times: draw a line. What it does not define is \"about\", \"evenly\" and the direction of each line. A person settles these by judgement, line by line, while drawing. A program has to settle them before it starts.\n\nWhat the code decides\n\nThe sketch below makes four decisions. Each is JAEV's, not LeWitt's:\n\nThe wall. 4 by 2.5 metres. The instruction fits any wall; code needs numbers.\n\n\"About 25 cm\". Every line is between 22.5 and 27.5 cm long.\n\n\"Evenly\". The wall is divided into a grid of 125 by 80 cells, which makes exactly 10,000, and the centre of one line is placed at random inside each cell.\n\nDirection. Any angle, all equally likely.\n\nNew drawing\nReconstruction by JAEV after the instruction for Sol LeWitt's Wall Drawing 86: 10,000 lines on a wall assumed to be 4 × 2.5 m. The wall size, the line lengths, the grid used for \"evenly\" and the random angles are JAEV's choices; on a real wall the drafters decide, by hand, in pencil. Not the work. Code CC BY 4.0.\n\nEach of the four choices replaces a decision that a drafter makes on the wall. Casey Reas began his project {Software} Structures for the Whitney Museum of American Art the same way, \"by implementing three of Lewitt's drawings in software and then making modifications\". The program can draw the work again at any time, but each drawing varies only as far as the code allows.\n\nLeWitt also used instructions to produce complete series rather than open executions. Variations of Incomplete Open Cubes (1974) \"proposes all of the 122 variations in which a cube can be incomplete\". Olof Broström's Automatic Colour Cubes at JAEV takes those 122 variations as its rule, one cube a day."},
{"type": "note", "title": "Studies in Perception I (Knowlton and Harmon, 1966)", "url": "https://jaev.gallery/notes/knowlton-harmon-studies-in-perception/",
   "description": "Studies in Perception I, the Bell Labs computer nude of 1966: a photograph turned into a mosaic of electronic symbols. The method, and what happened.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Ken Knowlton", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6387961"}, {"name": "Leon Harmon", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6524673"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Bell Labs", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q217365"}, {"name": "Museum of Modern Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q188740"}, {"name": "Cybernetic Serendipity", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5197816"}],
   "sources": [{"title": "Ken Knowlton, “Mosaic Portraits: New Methods and Strategies”. PAGE 59, Computer Arts Society, Winter 2004/2005 (Internet Archive copy)", "url": "https://web.archive.org/web/20070926215810/http://lansdown.mdx.ac.uk/CAS/page/page59.pdf"}, {"title": "“Leon Harmon”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Leon_Harmon"}, {"title": "“Ken Knowlton”. Wikipedia (English)", "url": "https://en.wikipedia.org/wiki/Ken_Knowlton"}, {"title": "“Cybernetic Serendipity: The Computer and the Arts”, Studio International special issue, ed. Jasia Reichardt, 1968. Contents", "url": "https://studiointernational.com/index.php/cybernetic-serendipity-the-computer-and-the-arts"}, {"title": "Kenneth C. Knowlton, Nude (Study in Perception), 1966. ACM SIGGRAPH History Archive", "url": "https://history.siggraph.org/artwork/kenneth-c-knowlton-nude-study-in-perception/"}, {"title": "Leon Harmon and Ken Knowlton, Computer Nude (Studies in Perception I), 1967. Buffalo AKG Art Museum", "url": "https://buffaloakg.org/artworks/p20142-computer-nude-studies-perception-i"}, {"title": "Kenneth Knowlton and Leon Harmon, Studies in Perception I, 1967. Thoma Foundation", "url": "https://thomafoundation.org/artwork/studies-in-perception/"}],
   "related": {"notes":["michael-noll-computer-composition-with-lines","cybernetic-serendipity","charles-csuri-hummingbird","floyd-steinberg-dithering"],"editorial":["plotter-art","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/knowlton-harmon-studies-in-perception-jaev.jpg", "alt": "Left: a column of seven small squares, from light to dark: empty, a dot, a ground sign, a capacitor, a resistor zigzag, a diode and a transistor symbol. Right: a large grid of the same tiny symbols on warm paper; ground signs fill the background, and denser symbols build up a sphere that is light at the upper left and dark at the lower right.", "credit": "Diagram by JAEV of the method: each cell of a picture is replaced by a symbol for an electronic part, chosen by how dark the cell is. The scale of symbols and the test picture, a sphere, are JAEV's own, not Knowlton and Harmon's work. CC BY 4.0."},
   "text": "Studies in Perception I is a large picture of a reclining nude made in 1966 at Bell Telephone Laboratories in New Jersey by Ken Knowlton (1931–2022) and Leon Harmon (1922–1983). Seen close up, it is a grid of tiny symbols for electronic parts. From a distance, the symbols merge into a photograph of the dancer Deborah Hay.\n\nHow the picture was made\n\nA photograph was scanned with a camera, and the analogue voltages from the scan were converted into binary numbers. Each number then chose a typographic symbol by its density, as in halftone printing: a part of the picture that should look light got a symbol with little ink, a dark part a symbol with much ink. The symbols were, in Knowlton's words, \"small electronic symbols for transistors, resistors and such\".\n\nThe diagram above shows the principle with a scale and a test picture of JAEV's own. Making grey from black marks on white is also what dithering does.\n\nA prank, then a press photo\n\nKnowlton later called the picture a \"sophomoric prank\". While Ed David, their manager two levels up, was away, Harmon proposed covering a whole wall of his office with it. The picture was 12 feet wide, and more visitors than expected could make out what it showed. After one day it was moved to David's basement, and the public relations department told them not to associate the name of Bell Labs with it.\n\nThen it was shown at a press conference on art and technology in Robert Rauschenberg's loft, and on 11 October 1967 it was printed at the top of the first page of the second section of The New York Times. After that, Knowlton writes, Bell Labs' advice changed: show it, but say that it was made at Bell Telephone Laboratories.\n\nAs art\n\nOf the title Knowlton writes: \"Sometimes it is excused by a more dignified title, like Studies in Perception I.\" The picture was submitted to the Museum of Modern Art's \"Machine Show\", The Machine as Seen at the End of the Mechanical Age, and to the Brooklyn Museum. Each time one of the two had to be named the artist; by the toss of a coin, \"Leon became the artist and I remained a technologist\". In 1968 the catalogue of Cybernetic Serendipity in London printed \"Computer-generated pictures\" by Harmon and Knowlton.\n\nThe work exists in several versions and sizes, and is dated 1966 or 1967. The SIGGRAPH archive lists a 1966 print of 60 × 144 inches; the screen prints at the Buffalo AKG Art Museum and the Thoma Foundation are dated 1967. The picture began, Knowlton wrote, his \"fascination with large pictures made of small things\", and he made mosaic portraits for decades afterwards. A mosaic, in his statement for SIGGRAPH, should make the viewer ask: \"Why do I see what I think I see?\" The first exhibitions of computer pictures, in 1965, are in JAEV's Generative Art."},
{"type": "note", "title": "Sture Johannesson (1935–2018)", "url": "https://jaev.gallery/notes/sture-johannesson/",
   "description": "Sture Johannesson, Swedish poster artist, turned to IBM's computers after the 1968 Lund poster scandal. How he and Sten Kallin made pictures from one line.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Sture Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5884840"}], "mentions": [{"name": "Charlotte Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4956816"}, {"name": "Sten Kallin", "type": "Person", "sameAs": null}, {"name": "Moderna Museet", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1274511"}, {"name": "IBM 1130", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q3146513"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}],
   "sources": [{"title": "“Sture Johannesson”. Wikipedia (Swedish)", "url": "https://sv.wikipedia.org/wiki/Sture_Johannesson"}, {"title": "Sture Johannesson. Counterclockwise Circumambulation. Lunds konsthall, 29 May – 22 August 2004, curator Åsa Nacking", "url": "https://lundskonsthall.se/en/exhibitions/2004/sture-johannesson/"}, {"title": "Sture Johannesson and Ann-Charlotte Johannesson, interviewed by Anna Orrghen, 2 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/4-ann-charlotte-och-sture-johannesson.pdf"}, {"title": "Sten Kallin, interviewed by Anna Orrghen, 10 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "Anna Orrghen, Från matematikmaskin till IT. Fokusgrupp: Media. Slutrapport. Tekniska museet, Stockholm, 2008", "url": "https://www.tekniskamuseet.se/app/uploads/2016/11/slutrapport-media-anna-orrghen.pdf"}, {"title": "Sture Johannesson, works in the collection. Moderna Museet, Stockholm", "url": "https://sis.modernamuseet.se/en/people/462/sture-johannesson/objects"}],
   "related": {"notes":["digitalteatern-malmo","astrid-sampe-computer-textile","ibm-1130-swedish-computer-art","calcomp-565"],"editorial":["computer-art-in-sweden","the-colour-cubes"],"exhibitions":["automatic-colour-cubes"]},
   "image": {"url": "https://jaev.gallery/assets/notes/sture-johannesson-2005-leffmann.jpg", "alt": "Sture Johannesson, an older man with glasses, a grey beard and long grey hair tied back, in a yellow jacket, smiling and holding a small paper cup.", "credit": "Sture Johannesson in 2005. Photo: Jonn Leffmann, CC BY 3.0, via Wikimedia Commons."},
   "text": "Sture Johannesson (1935–2018) was a Swedish poster artist who became one of the first artists in Sweden to make pictures with a computer. He was born in Vinslöv in Skåne and died in Skanör. His computer pictures were made at IBM with the engineer Sten Kallin.\n\nThe poster, 1968\n\nIn the 1960s Johannesson made political posters, and with his wife, the textile artist Charlotte Johannesson, he ran Galleri Cannabis in Malmö. In 1968 Lunds konsthall asked him for a poster for Underground, an exhibition planned for 1969. The poster, Friheten på barrikaderna II, a parody of Delacroix's Liberty Leading the People, was attacked as drug propaganda. The exhibition never opened and the director, Folke Edwards, resigned. The konsthall stayed closed for \"several months\" according to its own account, for a year and a half according to Johannesson.\n\nAfterwards, he said, no Swedish venue would show him. He turned to IBM instead, by letter in his own account, by telephone in Kallin's. It reached Kallin, who taught programming there. Johannesson was given a key to IBM's laboratory in Solna, where he could let himself in and lock up when he left: \"there I had an artistic freedom that does not exist in the art world.\"\n\nINTRA: one line\n\nTheir first project, INTRA, ran from 1969 to 1974 on an IBM 1130 with a pen plotter. Johannesson came with an \"alphabet\" of three signs he had already painted, printed and fired in ceramic: a keyhole, a heart, and the shape, like a crown, that the two make when laid on top of each other. Kallin wrote programs that drew forms as curves from mathematical formulas. The rule was that each picture was a single line: \"It is all just one line, and that is the point.\" They used the pen's slight wobble on purpose, and lines laid close together produced moiré.\n\nJohannesson did not program. Kallin finished each program and gave him as many parameters as he could, so that Johannesson sat at the machine and chose the values. Kallin thought the main creative part lay with whoever designs the program, \"because it sets the frame entirely\". Programs of the same kind drew a three-dimensional section sign (§), Johannesson's comment on Swedish bureaucracy, and a gramophone record as one line, for a record sleeve by the Skåne musician Peps Persson. Two works titled Datorserigrafi IBM (1973 and 1974) are among the 35 works by Johannesson in Moderna Museet's online collection.\n\nDigitalteatern and EPICS\n\nIn the early 1980s the Johannessons ran their own Apple-based studio, Digitalteatern, in Malmö. In the mid-1980s Johannesson and Kallin began a second project, EPICS (Exploring Picture Space), on a PC AT that IBM lent him. Each element in a picture was given a field of force around it, like gravity, that fell off with distance, and the program made the fields visible. The plan was to analyse paintings such as Cézanne's bathers this way; it got no further than mathematical objects.\n\nOf his work with Kallin, Johannesson said it was not really computer art but \"a way of using the computer to show and learn more about things one could use in any kind of picture-making\". He was critical of the colour cubes from Lund University's computing centre that became works by Beck & Jung, told in The colour cubes. The same cube is a starting point for Olof Broström's Automatic Colour Cubes at JAEV."},
{"type": "note", "title": "Tektronix 4010 storage tube terminal", "url": "https://jaev.gallery/notes/tektronix-4010/",
   "description": "The Tektronix 4010 graphics terminal of the early 1970s: how its storage tube kept a drawing on screen without memory, its 1024 × 780 points, and PLOT-10.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Tektronix 4010", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q7695503"}, {"name": "direct-view bistable storage tube", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5280225"}], "mentions": [{"name": "Tektronix", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1347679"}, {"name": "PLOT-10", "type": "Thing", "sameAs": null}],
   "sources": [{"title": "“4010”. TekWiki", "url": "https://w140.com/tekwiki/wiki/4010"}, {"title": "“Tektronix 4010”. Department of Computer Science, University of York, 50 years exhibition", "url": "https://www.york.ac.uk/computer-science/about/news/50-years/exhibition/tektronix-4010/"}, {"title": "Tektronix 4010 Maintenance Manual (070-1183-01, rev. B, April 1976). Tektronix, via Bitsavers and the Internet Archive", "url": "https://archive.org/details/bitsavers_tektronix40MaintenanceManualApr1976_43267116"}, {"title": "“Tektronix 4010-1”. PDP8Online (David Gesswein)", "url": "https://pdp8online.com/tek4010/tek4010.shtml"}, {"title": "PLOT-10 Terminal Control System User's Manual (062-1474-00), April 1972. Tektronix, via Bitsavers and the Internet Archive", "url": "https://archive.org/details/bitsavers_tektronixp0TerminalControlSystem4010UsersManualApr_5470592"}],
   "related": {"notes":["punched-paper-tape","hp-gl","calcomp-565","hp-7475a"],"editorial":["plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/tektronix-4010-us-map-gesswein.jpg", "alt": "A green screen in a dark grey frame. Thin bright green lines draw the outline of the United States with the borders of every state. Top left, a few lines of green text. Below the screen a yellowed paper label begins: Do not leave display on CRT tube for extended periods of time. Always PAGE CRT to clear the screen.", "credit": "A Tektronix 4010 showing a map of the United States from an example data file Tektronix supplied with its terminals. Photo: David Gesswein (PDP8Online), CC BY-SA 4.0, via Wikimedia Commons."},
   "text": "The Tektronix 4010 is a computer terminal that could draw, made by Tektronix in the early 1970s. Its screen kept every line drawn on it until it was erased, so a computer could build up a detailed drawing without any picture memory. According to TekWiki it was announced in October 1971; the University of York, which owns one, says it was released in 1973.\n\nThe storage tube\n\nOn an ordinary television-type tube a picture has to be redrawn continually, which means holding it in memory. The 4010 used a storage tube. Tektronix's manual says the data on the screen \"has only to be written once\"; after that the tube itself keeps the image, for up to an hour without damage to the screen.\n\nThe price was that nothing could be removed. To change one line, the whole screen was cleared with the PAGE key and the drawing sent again. The label on the terminal in the photograph above asks users to press PAGE rather than leave a picture on the tube for a long time.\n\nWhat it draws\n\nIn text mode the 4010 showed 35 lines of up to 74 upper-case characters. A control character, GS, switched it to graph mode, and from then on the computer sent coordinates and the terminal drew straight lines, called vectors, from point to point. The screen had 1,024 addressable points across and 780 visible points up.\n\nThis is close to how a pen plotter is told what to do: move to a point without drawing, then draw a straight line to the next (see HP-GL). Tektronix's own graphics software, PLOT-10, offered FORTRAN routines named Draw, Move, Point Plot and Dash, and was sold with its source code either on punched paper tape or on punched cards.\n\nPrice and family\n\nTekWiki gives $3,950 as the price in a 1971 catalogue. In Britain it sold for £3,140, and connecting it to the host computer cost another £230. Bigger models followed. In 1974 came the 4014 with a 19-inch screen, and in 1979 the 4016 with a 25-inch one.\n\nThe machines artists drew on in the same years are described in the note on the CalComp 565 and in JAEV's text on plotter art."},
{"type": "note", "title": "Tendencies 4: Computers and Visual Research (Zagreb, 1968–69)", "url": "https://jaev.gallery/notes/tendencies-4-zagreb/",
   "description": "Tendencies 4 brought computer art into the New Tendencies movement in Zagreb: a colloquy in August 1968, a journal and an exhibition in 1969.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "New Tendencies", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1568501"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}],
   "sources": [{"title": "“bit international. [Nove] tendencije. Computer und visuelle Forschung. Zagreb 1961–1973”. Exhibition page, ZKM Karlsruhe, 2008–09", "url": "https://zkm.de/en/node/9382"}, {"title": "Darko Fritz, “Vladimir Bonačić: Computer-Generated Works Made within Zagreb’s New Tendencies Network (1961–1973)”. Leonardo 41, no. 2, 2008, pp. 175–183", "url": "https://monoskop.org/images/7/7c/Fritz%2C_Darko_%282008%29_-_Vladimir_Bonacic.pdf"}, {"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal, Spring 2009", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}, {"title": "Christoph Klütsch, “The Summer 1968 in London and Zagreb: Starting or End Point for Computer Art?”. Creativity & Cognition, 2005", "url": "https://monoskop.org/images/2/2e/Kluetsch_Christoph_2005_The_Summer_1968_in_London_and_Zagreb_Starting_or_End_Point_for_Computer_Art.pdf"}, {"title": "“Timeline: Events”. DAM Digital Art Museum, Berlin", "url": "https://dam.org/museum/exhibitions_ui/timelines/events/"}, {"title": "“bit international – [Nove] tendencije. Computer und visuelle Forschung. Zagreb 1961–1973”. Exhibition page, Neue Galerie Graz, Universalmuseum Joanneum, 2007", "url": "https://www.museum-joanneum.at/neue-galerie-graz/unser-programm/ausstellungen/event/bit-international-nove-tendencije"}],
   "related": {"notes":["generative-computergrafik-stuttgart-1965","frieder-nake-hommage-a-paul-klee","georg-nees-schotter"],"editorial":["generative-art","there-should-be-no-computer-art","georg-nees","plotter-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/tendencies-4-zagreb-jaev.jpg", "alt": "A line drawing of an 80-column punched card with a cut corner. Small black rectangular holes in twelve rows spell out text in the card code; unpunched positions are faint grey marks.", "credit": "Diagram by JAEV: an 80-column punched card, punched in the IBM 029 code with the words “Tendencies 4 Computers and Visual Research Zagreb 1968-69”. CC BY 4.0."},
   "text": "Within the framework of Tendencies 4 (Tendencije 4), a series of exhibitions and symposia entitled Computers and Visual Research took place in Zagreb in 1968 and 1969. It brought computer art into the New Tendencies movement. Its histories set it beside London's Cybernetic Serendipity, which opened one day before the Zagreb colloquy in August 1968.\n\nNew Tendencies\n\nNew Tendencies began in 1961 in Zagreb, with an exhibition of concrete and constructive art organised by the city's Gallery of Contemporary Art, now the Museum of Contemporary Art. The artists called their work visual research: experiments with perception, light and movement, meant as research rather than as goods for the art market. By the mid-1960s Op art had absorbed much of it. The movement was in crisis in 1967, so the organisers postponed that year's exhibition by a year and dropped \"New\" from its name.\n\nThe colloquy, August 1968\n\nThe new direction was the computer. On 3 and 4 August 1968 Zagreb held an international colloquy, Computers and Visual Research. It opened one day after Cybernetic Serendipity opened at the Institute of Contemporary Arts in London. The critic Boris Kelemen had put \"visual research\" into the title, and the organising committee included Frieder Nake in Stuttgart, Leslie Mezei in Canada and Abraham Moles in France. Speakers ranged from artists to engineers from Zagreb's research institutes. According to Christoph Klütsch's account of the papers, Nake said that Cybernetic Serendipity had mainly addressed the play instinct, and that Tendencies 4 might address social consciousness.\n\nNake later put the difference this way: London was art as an event, Zagreb was art as research.\n\nbit international\n\nIn 1968 the gallery also started a journal, bit international, on information theory, exact aesthetics, design and media. Most of its first issue was taken up by Max Bense and Moles writing on information aesthetics, the theory that tried to measure art by order and complexity. Nine issues appeared; the sources disagree on whether the last came out in 1972 or 1973.\n\nThe exhibition, 1969\n\nThe exhibition ran from 5 May to 30 August 1969. According to Darko Fritz, it showed 189 computer-generated works by 33 artists or groups from 12 countries. A jury of Umberto Eco, Karl Gerstner, Vera Horvat-Pintarić, Kelemen and Martin Krampen gave prizes for computer and visual research to Vladimir Bonačić, Marc Adrian and the group Compos 68.\n\nBonačić, a scientist at the Ruđer Bošković Institute in Zagreb, showed seventeen works. As part of the exhibition he also put a large computer-controlled light object on the façade of the NaMa department store on Kvaternik Square.\n\nRadoslav Putar, one of the curators of New Tendencies, summed up the change in the catalogue: the New Tendencies artists \"have all dreamt of machines—and now the machines have arrived\", but from an unexpected direction, \"accompanied by people who were neither painters nor sculptors\".\n\nAfterwards\n\nThe programme continued until 1973, when Tendencies 5 showed computer work beside the earlier visual research and conceptual art. In 2007 the Neue Galerie Graz reconstructed the story in the exhibition bit international, curated by Darko Fritz in collaboration with the Museum of Contemporary Art in Zagreb; an expanded version was shown at the ZKM in Karlsruhe in 2008–09. Nees's exhibition in Stuttgart, three years before Zagreb, is in Generative Computergrafik."},
{"type": "note", "title": "Truchet tiles", "url": "https://jaev.gallery/notes/truchet-tiles/",
   "description": "Truchet tiles are squares split along the diagonal into two colours, described by Sébastien Truchet in 1704. How they combine, and what happens at random.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Truchet tiles", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q7847153"}], "mentions": [{"name": "Sébastien Truchet", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1410935"}, {"name": "Cyril Stanley Smith", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4424880"}],
   "sources": [{"title": "Stéphane Vinatier and William Reginald Alcorn, “Mathematics as seen by an artist: Inspiring mathematical objects”. EMS Magazine 135 (2025), pp. 20–31", "url": "https://euromathsoc.org/magazine/articles/248"}, {"title": "Nick Montfort, Patsy Baudoin, John Bell, Ian Bogost, Jeremy Douglass, Mark C. Marino, Michael Mateas, Casey Reas, Mark Sample and Noah Vawter, 10 PRINT CHR$(205.5+RND(1)); : GOTO 10. MIT Press, 2012. Chapter “Regularity”", "url": "https://10print.org/"}, {"title": "Eric W. Weisstein, “Truchet Tiling”. MathWorld, Wolfram Research", "url": "https://mathworld.wolfram.com/TruchetTiling.html"}],
   "related": {"notes":["ten-print-maze","vera-molnar-interruptions","georg-nees-schotter"],"editorial":["generative-art","vera-molnar"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/truchet-tiles-douat-1722-plate.jpg", "alt": "An engraved book page with six square patterns numbered 19 to 24. Each is made of small square tiles split diagonally into a hatched dark half and a light half, turned so that together they form diamonds, crosses and zigzags.", "credit": "Tilings 19–24 made with Truchet's tile, a plate from Dominique Doüat, Méthode pour faire une infinité de desseins différens (Paris, 1722). Getty Research Institute, via the Internet Archive. Public domain."},
   "text": "Truchet tiles are square tiles divided along one diagonal into two colours. Father Sébastien Truchet (1657–1729) described them in 1704 in a paper for the Académie Royale des Sciences in Paris, \"Mémoire sur les combinaisons\", and showed how a single tile, turned in different directions, makes a large number of patterns.\n\nThe tile\n\nTruchet wrote that at a château called La Motte S. Lyé, four leagues from Orléans, he had found \"several square fayence tiles divided into two colors by a diagonal line\", intended to tile a chapel and several other rooms. One half of each tile is dark, the other light. Because a square can be turned four ways, the dark triangle can lie in any of the four corners.\n\nCounting the combinations\n\nTruchet began with two tiles placed side by side. The first can take four orientations and so can the second, which can also be placed against any of the four sides of the first, giving 4 × 4 × 4 = 64 combinations.\n\nIn 1722 Dominique Doüat published Méthode pour faire une infinité de desseins différens, with 72 tilings made from the same tile. In 1987 the historian of science Cyril Stanley Smith and Pauline Boucher returned to the memoir in the journal Leonardo, calling it \"in essence a graphical treatment of combinatorics\".\n\nTiles at random\n\nTruchet's and Doüat's patterns are all regular and symmetrical. Smith tried the opposite: he arranged the tiles at random orientations. He then removed the solid colour and kept only the diagonal line, which leaves two orientations instead of four. The result looks like the maze printed by the one-line Commodore 64 program 10 PRINT, published five years earlier.\n\nA later variant replaces the diagonal with two quarter-circle arcs, centred on opposite corners, each with a radius of half the tile's edge. It too has two orientations. Wherever two tiles meet, an arc continues into the next one, so a random grid of them forms unbroken curves, some of which close into loops.\n\nNew drawing\nSketch by JAEV: a 12 × 12 grid of tiles, each turned at random. The drawings alternate between Truchet's tile of 1704, split into a dark and a light triangle with four orientations, and the later variant with two quarter-circle arcs and two orientations. Not a reproduction of Truchet's or Doüat's plates. Code CC BY 4.0.\n\nThe tile is a small example of a rule that makes many images: one element, a few permitted states, and a way of choosing between them. The choice can be a plan, as in Truchet's plates, or chance, as in Smith's grid and in Vera Molnár's collage Quatre éléments distribués au hasard (1959), which the authors of 10 PRINT place beside the maze. See also Generative art."},
{"type": "note", "title": "TSP art", "url": "https://jaev.gallery/notes/tsp-art/",
   "description": "TSP art draws a picture with one closed line through thousands of dots, found by solving the travelling salesman problem. The method, step by step.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "travelling salesperson problem", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q322212"}], "mentions": [{"name": "Robert A. Bosch", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q102341902"}, {"name": "Craig S. Kaplan", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q102259252"}, {"name": "Concorde TSP Solver", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5158938"}, {"name": "Mona Lisa", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q12418"}],
   "sources": [{"title": "Craig S. Kaplan and Robert Bosch, “TSP Art”. Bridges: Renaissance Banff, 2005, pp. 301–308", "url": "https://archive.bridgesmathart.org/2005/bridges2005-301.html"}, {"title": "“Travelling salesman problem”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Travelling_salesman_problem"}, {"title": "“Mona Lisa TSP Challenge”. University of Waterloo", "url": "https://www.math.uwaterloo.ca/tsp/data/ml/monalisa.html"}, {"title": "“Robert A. Bosch”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Robert_A._Bosch"}, {"title": "Windell Oskay, “StippleGen: Weighted Voronoi stippling and TSP paths in Processing”. Evil Mad Scientist Laboratories, 12 April 2012", "url": "https://www.evilmadscientist.com/2012/stipplegen-weighted-voronoi-stippling-and-tsp-paths-in-processing/"}],
   "related": {"notes":["plotter-path-optimisation","weighted-voronoi-stippling","floyd-steinberg-dithering","line-hatching"],"editorial":["plotter-art","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/tsp-art-jaev.jpg", "alt": "A cube seen from one corner, drawn on warm paper with a single unbroken black line that winds like a maze. On the top face the line makes wide, open loops; on the left face it is closer; on the right face it is packed so tightly that the face looks dark.", "credit": "Drawing by JAEV after the method of Robert Bosch and Adrianne Herman (2004): a cube in three tones, 3,000 dots placed by weighted Voronoi stippling, joined by one closed line found with a nearest-neighbour tour improved by 2-opt. Not a work by Bosch. CC BY 4.0."},
   "text": "TSP art is a way of drawing a picture with one closed line that never crosses itself. Dots are scattered over the paper, more where the picture is dark, and a single line is drawn through all of them as short as possible. Finding that line is the travelling salesman problem. The method was introduced by Robert Bosch and Adrianne Herman in 2004, in a two-page paper in Operations Research Letters.\n\nThe travelling salesman\n\nThe travelling salesman problem asks for \"the shortest possible route that visits each city exactly once and returns to the origin city\". It is NP-hard: no known method finds the best route quickly once there are many cities. The best route can never cross itself, since two crossing stretches can always be swapped for two shorter ones, so it is \"guaranteed to be a simple, closed polygon\". A line that visits dots packed close together stays close together, and the picture appears.\n\nHow it works\n\nCraig S. Kaplan and Bosch describe it as two optimisations, one after the other: first place the dots, then link them.\n\nPlacing the dots. In Bosch and Herman's grid method, the picture is divided into small square cells. Each cell gets a number of dots that depends on its mean brightness: none where it is white, up to a chosen maximum where it is black. The dots are put at random places inside the cell.\n\nLinking them. Bosch and Herman passed the dots to the Lin–Kernighan solver in the Concorde program, which finds a route that is \"probably not optimal, but that is almost always simple\".\n\nBetter dots. Randomly placed dots can lie very close to each other and give short, jagged bits of line. Kaplan and Bosch got tidier drawings, with fewer dots, by placing them with weighted Voronoi stippling, which spaces the dots evenly.\n\nNew drawing\nSketch by JAEV after Bosch and Herman's grid method: a random grey picture in 24 × 24 cells, each given 0 to 4 dots at random places by its brightness, then one closed line through all the dots, found by JAEV's simple solver (nearest neighbour, then swapping crossing stretches), not by Concorde. Code CC BY 4.0.\n\nThe Mona Lisa\n\nIn February 2009 Bosch made a TSP problem of 100,000 dots from the Mona Lisa. The University of Waterloo offers 1,000 dollars to anyone who finds a shorter route than the best known one, found by Yuichi Nagata in March 2009. Computation has shown that the best possible route can be at most 107 units shorter, out of 5,757,191. Bosch, a professor of mathematics at Oberlin College, collected such drawings in the book Opt Art (Princeton University Press, 2019).\n\nOn a plotter\n\nA TSP drawing is ideal for a pen plotter: the pen goes down once and comes up once. The free program StippleGen from Evil Mad Scientist Laboratories places the dots with weighted Voronoi stippling and can \"generate a TSP path from the stippled image\" for their drawing machines. The same problem in its everyday form, putting the separate lines of an ordinary drawing in a good order, is described in plotter path optimisation."},
{"type": "note", "title": "Voronoi diagrams and Delaunay triangulation", "url": "https://jaev.gallery/notes/voronoi-delaunay/",
   "description": "A Voronoi diagram splits a plane into the areas nearest each point; the Delaunay triangulation joins neighbours. How both work, with a live sketch.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "Voronoi diagram", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q757267"}, {"name": "Delaunay triangulation", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q192445"}], "mentions": [{"name": "Georgy Voronoy", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q268869"}, {"name": "Boris Delaunay", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q893737"}, {"name": "Lloyd's algorithm", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2835805"}, {"name": "Fortune's algorithm", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5472844"}],
   "sources": [{"title": "“Voronoi diagram”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Voronoi_diagram"}, {"title": "J. J. O'Connor and E. F. Robertson, “Georgy Fedoseevich Voronoy”. MacTutor History of Mathematics", "url": "https://mathshistory.st-andrews.ac.uk/Biographies/Voronoy/"}, {"title": "“Delaunay triangulation”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Delaunay_triangulation"}, {"title": "J. J. O'Connor and E. F. Robertson, “Boris Nikolaevich Delone”. MacTutor History of Mathematics", "url": "https://mathshistory.st-andrews.ac.uk/Biographies/Delone/"}],
   "related": {"notes":["weighted-voronoi-stippling","poisson-disc-sampling","reaction-diffusion","truchet-tiles"],"editorial":["generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/voronoi-delaunay-jaev.jpg", "alt": "A rectangle divided into about sixty irregular polygons by black lines, with a black dot inside each. Thin red lines join each dot to the dots of the neighbouring polygons, forming a net of triangles that crosses every black edge.", "credit": "Diagram by JAEV: 64 random points kept at least a fixed distance apart. Black: their Voronoi cells, computed by cutting the frame along the perpendicular bisector to every other point. Red: the Delaunay triangulation, joining points whose cells share an edge. CC BY 4.0."},
   "text": "A Voronoi diagram divides a plane among a set of points, giving each point the area of all places that are nearer to it than to any other point. The Delaunay triangulation joins every point to the points whose areas touch its own. The two are named after the mathematicians Georgy Voronoy (1868–1908) and Boris Delaunay (1890–1980), and each can be made from the other.\n\nThe cells\n\nStart with some points, called sites. For one site, take every other site in turn and draw the line exactly halfway between the two, at right angles to the line joining them (the perpendicular bisector). Everything on this site's side of that line is nearer to it. What is left after all the other sites have cut their half away is the site's Voronoi cell. The image at the top and the sketch below are made exactly like this.\n\nThe idea is older than the name. Dirichlet used such cells in 1850 in a study of quadratic forms, and Alfred H. Thiessen used them in 1911 to estimate rainfall, which is why they are also called Thiessen polygons. Voronoy defined and studied the general case, in any number of dimensions, in 1908, the year he died.\n\nThe triangles\n\nJoin each site to every site whose cell shares an edge with its own, and the plane is covered with triangles: the Delaunay triangulation, the \"dual\" of the Voronoi diagram. It has a simple test: the circle through the three corners of any triangle has no other site inside it. Of all the ways of joining the same points into triangles, it is the one whose smallest angle is as large as possible.\n\nDelaunay (in Russian Delone) gave a talk called \"Sur la sphère vide\", on the empty sphere, at the International Congress of Mathematicians in Toronto in 1924; Wikipedia dates his work on the triangulation from 1934.\n\nNew drawing\nLive sketch by JAEV: 30 to 60 random sites. Solid lines: each site's Voronoi cell, cut out of the frame along the bisectors to every other site. Dashed lines: the Delaunay triangulation, joining sites whose cells share an edge. Click or tap the drawing to add a site and see the cells around it change. Code CC BY 4.0.\n\nFaster methods, and art\n\nThe method used here cuts every cell against every other site, so the work grows quickly with the number of sites. Fortune's algorithm builds the whole diagram in time proportional to n log n, and the Bowyer–Watson algorithm builds the Delaunay triangulation by adding one point at a time.\n\nIn Lloyd's algorithm the sites are moved, again and again, to the centre of their own cells, which spreads them out evenly. A weighted version of the idea, which places dots for drawings made only of points, is the subject of Weighted Voronoi stippling. For another way to spread points evenly, see Poisson disc sampling. See also Generative Art."},
{"type": "note", "title": "vpype: preparing SVG for a plotter", "url": "https://jaev.gallery/notes/vpype/",
   "description": "vpype, Antoine Beyeler's command-line tool for plotter files: its pipelines, what linemerge and linesort do, and how it writes HP-GL for old plotters.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "vpype", "type": "Thing", "sameAs": null}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Antoine Beyeler", "type": "Person", "sameAs": null}, {"name": "Scalable Vector Graphics", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2078"}, {"name": "Python", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q28865"}, {"name": "HP-GL", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1422842"}],
   "sources": [{"title": "vpype, README. GitHub (abey79/vpype)", "url": "https://github.com/abey79/vpype"}, {"title": "vpype. Python Package Index", "url": "https://pypi.org/project/vpype/#history"}, {"title": "“Command reference”. vpype documentation", "url": "https://vpype.readthedocs.io/en/latest/reference.html"}, {"title": "“Cookbook”. vpype documentation", "url": "https://vpype.readthedocs.io/en/latest/cookbook.html"}, {"title": "AxiDraw. axidraw.com", "url": "https://axidraw.com/"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}],
   "related": {"notes":["plotter-path-optimisation","line-hatching","hp-gl","hp-7475a","axidraw"],"editorial":["plotter-art"],"exhibitions":["unverified-air"]},
   "image": {"url": "https://jaev.gallery/assets/notes/vpype-jaev.jpg", "alt": "At the top, in monospace type: vpype read in.svg linesort write out.svg. Below, two frames with the same sixty short black lines in three clusters. In the left frame dashed red lines criss-cross the whole frame between them, labelled as read: pen-up travel 100 %. In the right frame the dashed red lines are short hops from each line to its neighbour, labelled after linesort: 14 %.", "credit": "Diagram by JAEV: the same 60 lines in the order they were written (left) and after sorting (right). Black: the pen draws. Dashed red: the pen is lifted and moves to the next line. Sorted by JAEV's own greedy code to show what linesort is for; not vpype output. CC BY 4.0."},
   "text": "vpype is a free command-line program for preparing vector drawings for a pen plotter, written in Python by Antoine Beyeler. Its own description is \"the Swiss-Army-knife command-line tool for plotter vector graphics\". Version 1.0 was published in November 2020, under the MIT licence.\n\nWhat it is for\n\nA drawing made by a program, saved as an SVG file, is usually not ready for a plotter. Its lines may be in the order the program happened to write them, broken into many pieces, or the wrong size for the paper. A plotter draws exactly what it is given, in that order, and lifts the pen for every jump between lines (see HP-GL). vpype rearranges the file before it goes to the machine: it lays the drawing out on a page, joins and sorts the lines, handles drawings in several layers for several colours, and can write the result for old plotters.\n\nHow it works\n\nvpype runs a pipeline of commands, each handing its result to the next:\n\nvpype read in.svg linemerge linesort write out.svg\n\nread loads the lines from an SVG file. linemerge joins lines whose ends almost touch, by default when the gap is at most 0.05 mm, so the pen does not lift between them. linesort puts the lines in an order that makes the pen-up travel short. By default it uses \"a fast, greedy algorithm\", going each time to a nearby line and reversing a line's direction when that helps. write saves the result. The documentation calls this kind of optimisation \"quite possibly the most common use of vpype\". The problem it solves is described in the note on plotter path optimisation; the diagram above shows the effect on sixty short lines.\n\nvpype converts every curve, circle and Bézier into \"lines made of small segments\". For that reason it is not meant for general illustration or print work.\n\nHP-GL for old plotters\n\nIf the output file ends in .hpgl, vpype writes HP-GL instead of SVG. Because \"HPGL coordinate systems vary widely from plotter to plotter\", the plotter must be named with --device. Built-in profiles include the HP 7475A as well as Roland's DXY and Sketchmate. Other plotters can be added in a configuration file. Newer machines need no HP-GL: the AxiDraw's own software plots SVG files.\n\nPlug-ins and vsketch\n\nvpype can be extended with plug-ins. Among those listed in its README are hatched, which fills areas with hatching (see line hatching), and occult, which removes hidden lines. Beyeler's vsketch, a framework for writing plotter drawings in Python, is built on vpype.\n\nOlof Broström's Unverified Air at JAEV is stored as files for a pen plotter, in black, red and blue ink. The wider field is in JAEV's text on plotter art."},
{"type": "note", "title": "Weighted Voronoi stippling (Secord, 2002)", "url": "https://jaev.gallery/notes/weighted-voronoi-stippling/",
   "description": "Adrian Secord's weighted Voronoi stippling turns a grey image into evenly spaced dots, denser where it is dark, by moving each dot to its cell's centre.",
   "datePublished": "2026-10-21", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "stippling", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1640859"}, {"name": "centroidal Voronoi tessellation", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5062961"}], "mentions": [{"name": "Voronoi diagram", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q757267"}, {"name": "Lloyd's algorithm", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q2835805"}, {"name": "Craig S. Kaplan", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q102259252"}, {"name": "Robert A. Bosch", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q102341902"}],
   "sources": [{"title": "Nicolas P. Rougier, “[Re] Weighted Voronoi Stippling”. ReScience 3(1), 2017. Article and code on GitHub", "url": "https://github.com/ReScience-Archives/Rougier-2017"}, {"title": "Craig S. Kaplan and Robert Bosch, “TSP Art”. Bridges: Renaissance Banff, 2005, pp. 301–308", "url": "https://archive.bridgesmathart.org/2005/bridges2005-301.html"}, {"title": "“Lloyd's algorithm”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Lloyd%27s_algorithm"}, {"title": "Windell Oskay, “StippleGen: Weighted Voronoi stippling and TSP paths in Processing”. Evil Mad Scientist Laboratories, 12 April 2012", "url": "https://www.evilmadscientist.com/2012/stipplegen-weighted-voronoi-stippling-and-tsp-paths-in-processing/"}],
   "related": {"notes":["tsp-art","voronoi-delaunay","floyd-steinberg-dithering","plotter-path-optimisation"],"editorial":["plotter-art","generative-art"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/weighted-voronoi-stippling-jaev.jpg", "alt": "Three round fields of black dots on warm paper, all showing a ball lit from the upper left. Left: dots scattered unevenly, in clumps and gaps. Middle: fewer dots, each inside a grey polygon, with a short red line from each dot showing where it moves. Right: evenly spaced dots, sparse at the upper left and dense at the lower right. Small grey labels under each.", "credit": "Diagram by JAEV after the method of Adrian Secord (2002): a ball lit from the upper left. Left: 1,300 dots at random, more where it is dark. Middle: one round of the method with 260 dots, showing each dot's Voronoi cell (grey) and its move to the darkness-weighted centre of the cell (red). Right: the 1,300 dots after 40 rounds. CC BY 4.0."},
   "text": "Weighted Voronoi stippling is a method for turning a grey image into a drawing of dots, evenly spaced but packed closer where the image is dark. It was published by Adrian Secord in 2002 at NPAR, the ACM's symposium on non-photorealistic animation and rendering; his paper describes \"techniques for generating stipple drawings from grayscale images using weighted centroidal Voronoi diagrams\".\n\nStippling\n\nStippling is the old illustrator's technique that Secord set out to imitate: it \"places small dots of ink onto paper such that their density give the impression of tone\". Spacing is what makes it work. Dots scattered at random give, in Craig S. Kaplan and Robert Bosch's word, \"unappealing\" stipple drawings, because nothing controls how close a dot comes to its neighbours.\n\nHow it works\n\nThe method builds on Lloyd's algorithm, which Stuart P. Lloyd of Bell Labs proposed in 1957 and published only in 1982.\n\nScatter. Put the chosen number of dots on the image, for example at random, with more of them where it is dark.\n\nCells. Give every point of the image to whichever dot lies nearest, so that the image is divided into one region per dot, its Voronoi cell (see Voronoi diagrams).\n\nMove. Move each dot to the centre of its cell, then repeat from step 2.\n\nLloyd's algorithm, in its plain form, takes the ordinary centre of the cell's area, and the dots end up evenly spaced all over. Secord's change is to weight that centre by the image, with every pixel counting as much as it is dark; the centre of a cell is then pulled towards its darker part, the \"centre of mass\" if the image's tone gives the paper its weight. Round after round, dots drift into the dark areas. Since each dot also keeps its distance from its neighbours, they stay evenly spread.\n\nSecord computed the cells on graphics hardware, drawing a cone under each dot: seen from straight above, the cones form a Voronoi diagram. He stopped when the cells' sizes no longer changed much; the replication by Nicolas Rougier in 2017 simply ran 50 rounds.\n\nNew drawing\nSketch by JAEV after Secord's method: a hidden random grey picture and 700 dots, scattered at random and then moved for 40 rounds, each time to the darkness-weighted centre of the pixels nearest to them. The cells are found on a 140 × 140 grid rather than with graphics hardware. Code CC BY 4.0.\n\nFor plotters\n\nEach dot is a short touch of the pen, so a stipple drawing is a natural plotter drawing. Evil Mad Scientist Laboratories' free program StippleGen (2012), written in Processing, makes stipple drawings \"using Secord's algorithm\" and saves them for their drawing machines. Its other option, one continuous line through all the dots, is TSP art: Kaplan and Bosch used Secord's own implementation to place the dots for theirs, and found the drawings tidier than with dots placed at random. For dots on a fixed pixel grid instead, see Floyd–Steinberg dithering."},
{"type": "note", "title": "Zuse Graphomat Z64 (1961–1964)", "url": "https://jaev.gallery/notes/zuse-graphomat-z64/",
   "description": "The Zuse Graphomat Z64, the German flatbed plotter of 1961–64 that drew early works by Frieder Nake and Georg Nees: how it worked and where to see one.",
   "datePublished": "2026-10-20", "dateModified": "2026-10-20",
   "author": "JAEV Editorial",
   "about": [{"name": "Graphomat Z64", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q130493775"}, {"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}], "mentions": [{"name": "Konrad Zuse", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q60093"}, {"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}, {"name": "University of Stuttgart", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q122453"}, {"name": "ZKM | Center for Art and Media Karlsruhe", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q191228"}],
   "sources": [{"title": "Z 64 Graphomat (HZu.000005.0). ZCOM Zuse-Computer-Museum, Hoyerswerda, via museum-digital:sachsen", "url": "https://sachsen.museum-digital.de/object/23533"}, {"title": "Frieder Nake and Wolf Lieser, “60 Years of Algorithmic Art”. Digital Art Museum (DAM)", "url": "https://dam.org/museum/essays_ui/essays/frieder-nake-wolf-lieser-60-years-of-algorithmic-art/"}, {"title": "Georg Nees, Schotter, 1968–1970. Victoria and Albert Museum, London (catalogue text)", "url": "https://collections.vam.ac.uk/item/O221321/schotter-print-nees-georg/"}, {"title": "“Zuse Z64 Graphomat. Elektronisch gesteuerter Zeichentisch” (NL 207/4077). Deutsches Museum, Munich, archive", "url": "https://digital.deutsches-museum.de/en/digital-catalogue/archive-item/NL%2520207%252F4077/"}, {"title": "Manfred Mohr, “50 Year Celebration: Time Line”", "url": "https://emohr.com/ManfredMohr_50YearCelebration_TimeLine.html"}, {"title": "“Project Zuse”. Computer Museum, Department of Computer Science, University of Stuttgart", "url": "https://www.f05.uni-stuttgart.de/en/cs/department/computer-museum/projects-and-information/project-zuse/"}, {"title": "Frieder Nake, Hommage à Paul Klee 13/9/65 Nr. 2, 1965. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/47645"}, {"title": "Georg Nees, Achsenparalleler Irrweg, 1964. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/12178"}, {"title": "Z 64 Steuerschrank (control cabinet). ZCOM Zuse-Computer-Museum, Hoyerswerda, via museum-digital:sachsen", "url": "https://sachsen.museum-digital.de/object/23534"}],
   "related": {"notes":["generative-computergrafik-stuttgart-1965","georg-nees-schotter","frieder-nake-hommage-a-paul-klee","calcomp-565","benson-plotter"],"editorial":["plotter-art","georg-nees","manfred-mohr"],"exhibitions":[]},
   "image": {"url": "https://jaev.gallery/assets/notes/zuse-graphomat-z64-steve-parker.jpg", "alt": "A large flatbed drawing machine under a clear plastic cover in a museum: a grey pen head on a rail above sheets of paper with line drawings of ellipses and a building facade, a control panel with buttons on the right, a plate reading Graphomat, and a yellow label in front. A visitor's hand rests on the cover.", "credit": "A Zuse Graphomat Z64 in a museum display, 2006. Photo: Steve Parker, CC BY 2.0, via Wikimedia Commons."},
   "text": "The Graphomat Z64 is a pen plotter built by the computer pioneer Konrad Zuse's company from 1961 to 1964. Ninety-eight were made. Graphomats drew some of the first computer graphics shown as art, by Frieder Nake in Stuttgart and Georg Nees at Siemens.\n\nThe machine\n\nThe Z64 is a flatbed plotter: the paper lies still and the pen moves over it in both directions. An item in the Deutsches Museum archive calls it an \"elektronisch gesteuerter Zeichentisch\", an electronically controlled drawing table. According to the ZCOM Zuse-Computer-Museum in Hoyerswerda, the machine could draw in four colours and write lettering on its own. The museum presents it as the realisation of an idea Zuse had in 1945: that computers should also be able to draw.\n\nThe plotter did not have to stand next to the computer. A program punched the drawing into paper tape, which was carried to the plotter and read there. The pen moved in steps of 1/16 mm at up to 22.5 mm a second, and a straight line one metre long took about 45 seconds.\n\nNake's tape\n\nThe computing centre of the Technische Hochschule Stuttgart ordered a Z64 and got unit number 9, Nake recalled; it came without software, and he was told to write it. The centre's computer was not a Zuse machine, so he wrote his programs without being able to test them, punched them on tape and took them to Zuse's headquarters. There the plotter started, then stopped after five minutes, again and again. Nake picked up the punched-out scraps of paper from the floor, glued them into chosen holes in his tape, and the drawing ran. His programs ran on the centre's Standard Elektrik Lorenz ER56 and were drawn on the Z64, among them Hommage à Paul Klee 13/9/65 Nr. 2.\n\nNees at Siemens\n\nNees was a software engineer at Siemens, and according to the Victoria and Albert Museum he was instrumental in the company buying a Graphomat. He showed his drawings at the Technische Hochschule Stuttgart in February 1965, the exhibition described in the note on Generative Computergrafik. ZKM in Karlsruhe holds his Achsenparalleler Irrweg (1964), written in ALGOL for a Siemens 2002 computer and drawn in ink on the Z64. His best-known plotter work is Schotter.\n\nMohr in Darmstadt\n\nIn early 1970 Manfred Mohr, then in Paris, got access through a friend to a Zuse flatbed plotter and an IBM 7040 at the university in Darmstadt. There he drew his program P-21, his first drawings by a mechanical pen plotter, and called it \"a milestone\". He does not name the model. A few months later he was drawing on a Benson plotter in Paris.\n\nWhere to see one\n\nThe ZCOM Zuse-Computer-Museum in Hoyerswerda holds a Z64 with its control cabinet. Both were used in a drawing and design office in Hamburg. JAEV's editorial Plotter art places the Z64 among the other plotters artists have used since."},
{"type": "editorial", "title": "Is AI art art?", "url": "https://jaev.gallery/editorial/is-ai-art-art/",
   "description": "Is AI art really art? The same question was asked about photography in 1859 and computer art in 1965. What the old arguments say about AI images, music and authorship today.",
   "datePublished": "2026-10-25", "dateModified": "2026-10-25",
   "author": "JAEV Editorial",
   "about": [{"name": "AI art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q65066631"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "A. Michael Noll", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4648184"}, {"name": "Charles Baudelaire", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q501"}, {"name": "Walter Benjamin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q61078"}, {"name": "Hilma af Klint", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q436267"}, {"name": "Harold Cohen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92723"}, {"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "Ted Chiang", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q503095"}],
   "sources": [{"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal 68:1, Spring 2009, pp. 76–89", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}, {"title": "“Holly Herndon and Mat Dryhurst: xhairymutantx”. Whitney Museum of American Art, Whitney Biennial 2024", "url": "https://whitney.org/exhibitions/xhairymutantx"}, {"title": "A. Michael Noll, “First-Hand: Howard Wise Gallery Show of Digital Art and Patterns (1965)”. Engineering and Technology History Wiki", "url": "https://ethw.org/First-Hand:Howard_Wise_Gallery_Show_of_Digital_Art_and_Patterns_(1965):_A_50th_Anniversary_Memoir"}, {"title": "A. Michael Noll, “Human or Machine: A Subjective Comparison of Piet Mondrian's ‘Composition with Lines’ (1917) and a Computer-Generated Picture”. The Psychological Record 16, 1966, pp. 1–10", "url": "https://gwern.net/doc/culture/1966-noll.pdf"}, {"title": "Charles Baudelaire, “Salon de 1859”, part II, “Le public moderne et la photographie”. In Curiosités esthétiques, 1868. Wikisource", "url": "https://fr.wikisource.org/wiki/Curiosit%C3%A9s_esth%C3%A9tiques/Salon_de_1859"}, {"title": "Walter Benjamin, “The Work of Art in the Age of Mechanical Reproduction”, 1935, section VII. Translated by Harry Zohn", "url": "https://www.marxists.org/reference/subject/philosophy/works/ge/benjamin.htm"}, {"title": "Johann Joseph Fux, The Study of Counterpoint, from Gradus ad Parnassum. Translated and edited by Alfred Mann. W. W. Norton", "url": "https://wwnorton.co.uk/books/9780393002775-the-study-of-counterpoint"}, {"title": "“Musikalische Würfelspiele”, KV Anh. C 30.01. Köchel Catalogue Online, Mozarteum Foundation Salzburg", "url": "https://kv.mozarteum.at/en/work/musikalische-wurfelspiele-8820"}, {"title": "“Illiac Suite”. Distributed Museum, University of Illinois Urbana-Champaign", "url": "https://distributedmuseum.illinois.edu/?p=2122"}, {"title": "Brian Eno, “Generative Music”, talk in San Francisco, 8 June 1996. In Motion Magazine", "url": "https://inmotionmagazine.com/eno1.html"}, {"title": "Sol LeWitt, “Paragraphs on Conceptual Art”. Artforum 5:10, June 1967, pp. 79–83", "url": "https://gwern.net/doc/design/1967-lewitt.pdf"}, {"title": "André Breton, Manifesto of Surrealism, 1924. Translated by Richard Seaver and Helen R. Lane, 1969", "url": "https://theanarchistlibrary.org/library/andre-breton-manifesto-of-surrealism"}, {"title": "“About Hilma af Klint”. The Hilma af Klint Foundation", "url": "https://hilmaafklint.se/about-hilma-af-klint/"}, {"title": "Susan Tallman, “Painting the Beyond”. The New York Review of Books, 4 April 2019", "url": "https://www.nybooks.com/articles/2019/04/04/hilma-af-klint-painting-beyond/"}, {"title": "“Harold Cohen: AARON”. Whitney Museum of American Art, 3 February – 19 May 2024", "url": "https://whitney.org/exhibitions/harold-cohen-aaron"}, {"title": "Harold Cohen, “The Further Exploits of AARON, Painter”. Stanford Humanities Review 4:2, 1995 (Internet Archive copy)", "url": "https://web.archive.org/web/2010/http://www.stanford.edu/group/SHR/4-2/text/cohen.html"}, {"title": "Kevin Roose, “An A.I.-Generated Picture Won an Art Prize. Artists Aren't Happy”. The New York Times, 2 September 2022", "url": "https://www.nytimes.com/2022/09/02/technology/ai-artificial-intelligence-artists.html"}, {"title": "U.S. Copyright Office Review Board, decision on Théâtre D'opéra Spatial, 5 September 2023", "url": "https://www.copyright.gov/rulings-filings/review-board/docs/Theatre-Dopera-Spatial.pdf"}, {"title": "Obvious, Portrait of Edmond de Belamy, 2018. Christie's New York, Prints & Multiples, 25 October 2018, lot 363", "url": "https://www.christies.com/en/lot/lot-6166184"}, {"title": "“Thousands of Artists Sign Open Letter Protesting Christie's Upcoming All-A.I. Art Auction”. Smithsonian Magazine, February 2025", "url": "https://www.smithsonianmag.com/smart-news/artists-sign-open-letter-protesting-christies-upcoming-all-ai-art-auction-180986061/"}, {"title": "“Christie's AI Art Sale Results”. Artnet News, March 2025", "url": "https://news.artnet.com/market/christies-augmented-intelligence-ai-auction-results-2615818"}, {"title": "Christien Pheby, “Half of Americans think AI art will be used to spread false information”. YouGov, 30 May 2023 (survey of 2,000 US adults, 24–25 March 2023)", "url": "https://yougov.com/en-gb/articles/45765-half-americans-think-ai-art-will-be-used-spread-fa"}, {"title": "U.S. Copyright Office, Copyright and Artificial Intelligence, Part 2: Copyrightability, January 2025", "url": "https://www.copyright.gov/ai/Copyright-and-Artificial-Intelligence-Part-2-Copyrightability-Report.pdf"}, {"title": "Thaler v. Perlmutter, No. 23-5233, U.S. Court of Appeals for the D.C. Circuit, 18 March 2025", "url": "https://media.cadc.uscourts.gov/opinions/docs/2025/03/23-5233.pdf"}, {"title": "Thaler v. Perlmutter, No. 25-449, Supreme Court of the United States, docket (certiorari denied 2 March 2026)", "url": "https://www.supremecourt.gov/search.aspx?filename=/docket/docketfiles/html/public/25-449.html"}, {"title": "Allen v. Perlmutter, No. 1:24-cv-02665, U.S. District Court for the District of Colorado, complaint filed 26 September 2024", "url": "https://business.cch.com/ipld/AllenPerlmutterComp20240926.pdf"}, {"title": "Copyright, Designs and Patents Act 1988, section 9(3). legislation.gov.uk", "url": "https://www.legislation.gov.uk/ukpga/1988/48/section/9"}, {"title": "Ted Chiang, “Why A.I. Isn't Going to Make Art”. The New Yorker, 31 August 2024", "url": "https://www.newyorker.com/culture/the-weekend-essay/why-ai-isnt-going-to-make-art"}, {"title": "“algorithmic-art”, SKILL.md. Anthropic, anthropics/skills on GitHub", "url": "https://github.com/anthropics/skills/blob/main/skills/algorithmic-art/SKILL.md"}, {"title": "Bronwen Everill, “Solve for AI”. History News Network, 30 April 2025", "url": "https://www.historynewsnetwork.org/article/solve-for-ai"}, {"title": "National Council of Teachers of Mathematics, An Agenda for Action: Recommendations for School Mathematics of the 1980s, April 1980", "url": "https://www.nctm.org/Standards-and-Positions/More-NCTM-Standards/An-Agenda-for-Action-(1980s)/"}, {"title": "Frieder Nake, “There Should Be No Computer Art”. PAGE, Bulletin of the Computer Arts Society, no. 18, October 1971. Scan via compart, University of Bremen", "url": "https://compart.uni-bremen.de/publications/there-should-be-no-computer-art"}],
   "related": {"editorial":["there-should-be-no-computer-art","harold-cohen","georg-nees","sol-lewitt","the-rule-is-the-work"],"exhibitions":[],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/baudelaire-carjat-1862.jpg", "alt": "A black-and-white photograph of Charles Baudelaire, head and shoulders, in a dark coat and white shirt with a loose tie. His hair is receding and he looks straight at the camera with a serious face.", "credit": "Étienne Carjat, Charles Baudelaire, about 1862. Woodburytype from Galerie contemporaine, littéraire, artistique, Paris, 1876–84. British Library, via Wikimedia Commons; public domain. The poet who called photography the refuge of failed painters, photographed."},
   "text": "Stuttgart, 5 February 1965: a mathematician named Georg Nees opened a small exhibition of drawings at the Technische Hochschule, among the first exhibitions of computer art anywhere. A computer had calculated them, a plotter had drawn them. Artists came over from the city's Academy of Fine Arts for the opening, and one of them asked a question that is still being asked almost word for word.\n\nFrieder Nake, who was there, wrote it down: \"Tell me, Mr. Nees, can you make your machine draw like an artist's flow?\" Nees answered: \"Yes, I can. If you can tell me precisely how to define your way of drawing.\" According to Nake, the professors left the room. \"Who does he think we are?\"\n\nGeorg Nees in 1986. Photo: Alexander Kempkens, Wikimedia Commons, CC BY-SA 3.0.\n\nSixty years later the question is \"Is AI art art?\", and it is usually treated as new. It has been asked about almost every tool that made making easier, and the answers given then are the best guide to the answers now.\n\nThe short answer\n\nYes, in the only sense that has ever settled the question: art is what people make, show and look at as art, and a tool has never disqualified a work. Who the author is, is a separate question, and the law answers it differently from country to country. Whether a particular AI image is any good is a third question, and the answer is usually no, as it is for most images made with any tool. The rest of this text is about why those three questions keep getting mixed up, and what happened the last times they were asked.\n\n\"AI art\" also covers very different things. There are images made from a typed prompt in a few seconds. There are artists' own systems, built and trained over years, like Harold Cohen's AARON or xhairymutantx, a model that Holly Herndon and Mat Dryhurst trained on images of Herndon's own public persona for the 2024 Whitney Biennial. And there is AI as one tool among others inside work that is otherwise made by hand. The anger is mostly about prompt images; the history below is mostly about systems.\n\nNew York, 1965\n\nTwo months after Stuttgart, in April 1965, the Howard Wise Gallery in New York showed Computer-Generated Pictures by Bela Julesz and A. Michael Noll, two researchers at Bell Labs. Noll later quoted Stuart Preston's review in The New York Times: \"The wave of the future crashes significantly at the Howard Wise Gallery … Freed from the tedium of technique and the mechanics of picture making, the artist will simply 'create.'\" The irony is easy to hear, and so is the fear under it: that technique was what made someone an artist, and that a machine had just taken it away.\n\nNoll answered with an experiment. He had programmed a computer to make a picture in the manner of Piet Mondrian's Composition with Lines from 1917, short black bars on white, and showed reproductions of both to 100 people, nearly all of them employees at Bell Labs. 59 percent preferred the computer's picture. Only 28 percent could tell which was which. The paper, published in 1966, showed that viewers could not reliably tell the machine from the master. It could not show that this made the machine's picture art, and Noll did not claim it did.\n\nLeft: A. Michael Noll, Computer Composition with Lines, 1964 (© A. Michael Noll 1965), shown with his written permission; scan supplied by Noll. Right: Piet Mondrian, Composition in Line, 1916–17, Kröller-Müller Museum, Otterlo; public domain, via Wikimedia Commons.\n\nParis, 1859\n\nThe argument was already a hundred years old. In his review of the Paris Salon of 1859, Charles Baudelaire wrote that the photographic industry had become \"the refuge of every failed painter, too poorly gifted or too lazy to finish his studies\". Photography should know its place: its true duty was \"to be the servant of the sciences and the arts, but the very humble servant, like printing and shorthand, which have neither created nor taken the place of literature\" (both in our translation).\n\nReplace \"photographic industry\" with \"image generators\" and the passage could be posted today. It has the whole complaint in it: that the tool lets people skip the training, that people who skip the training are not real artists, and that the tool must stay a servant.\n\nWalter Benjamin, looking back at that debate in 1935, found it beside the point: \"Earlier much futile thought had been devoted to the question of whether photography is an art. The primary question – whether the very invention of photography had not transformed the entire nature of art – was not raised.\" Replace photography with AI, and the sentence describes the debate going on now.\n\nComposing by rule\n\nBehind \"is it art?\" there is usually a narrower question: did the person do it themselves? Composers have long worked by rules they did not invent. Johann Joseph Fux's Gradus ad Parnassum, a textbook of counterpoint published in Vienna in 1725, taught generations of them, Mozart and Haydn among them according to its English publisher, and nobody thinks a composer who follows music theory is less the author of the piece.\n\nA game for composing dances by throwing dice was once printed and sold under Mozart's name. Mozart's official catalogue lists the printed dice games as \"incorrectly assigned\", but somebody thought the name would sell them, and nobody seems to have thought composing by dice was shameful. In 1957 Lejaren Hiller and Leonard Isaacson at the University of Illinois had the university's computer compose the Illiac Suite for string quartet, which the university calls \"the first piece to use a computer for its composition\". In 1996 Brian Eno said that his ambient music was based on a simple idea: a system or a set of rules \"which once set in motion will create music for you\". That led him to ask who the author was. \"Am I the composer?\"\n\nNumbered bars from the dice game printed under Mozart's name. A table and two dice choose which of them are played. N. Simrock, Bonn. Bibliothèque nationale de France. Public domain, via Wikimedia Commons.\n\nIn visual art the turn came in 1967, when Sol LeWitt wrote that in conceptual art \"the idea becomes a machine that makes the art\". His wall drawings, still made by other people's hands following his written instructions, are still his.\n\nWho holds the pen\n\nIn 1924 André Breton defined surrealism as \"psychic automatism in its pure state\", art \"dictated by the thought, in the absence of any control exercised by reason, exempt from any aesthetic or moral concern\". The surrealists wanted to get the conscious artist out of the way.\n\nHilma af Klint had gone further, eighteen years earlier. In January 1906, according to the foundation that holds her work, the spiritual being Amaliel, one of the \"intermediaries of The High Masters\", offered her a commission, and she accepted it at once. By 1915 The Paintings for the Temple numbered 193 works. She explained, in the translation quoted by The New York Review of Books, that the first of them were made \"directly through me, without any preliminary drawings and with great force\", and: \"I had no idea what the paintings were supposed to depict.\" By her own account she was the instrument.\n\nHilma af Klint, The Ten Largest, No. 7, Adulthood, 1907, from The Paintings for the Temple. Tempera on paper mounted on canvas, 315 × 235 cm. The Hilma af Klint Foundation. Public domain, via Wikimedia Commons.\n\nHarold Cohen worked on the same question from the other side for the rest of his career. He conceived his program in the late 1960s and named it AARON in the early 1970s, and it went on drawing and painting for the rest of his life. He never claimed AARON was an artist, and he did not accept that the question had a simple answer either: \"If what AARON is making is not art, what is it exactly, and in what ways, other than its origin, does it differ from the 'real thing?'\"\n\nHow much the human matters to a work depends on what one thinks a human is. If the artist is a sovereign author, any tool that does part of the work is a threat. If, on the other hand, the artist is a channel – for a god, for the unconscious, for nature, for the accumulated rules of a culture – the tool becomes one more channel among them, and what counts is what comes through.\n\nNow\n\nIn September 2022 Jason M. Allen won the blue ribbon for emerging digital artists at the Colorado State Fair with Théâtre D'opéra Spatial, an image he had made with Midjourney. The New York Times quoted one reaction: \"We're watching the death of artistry unfold right before our eyes.\" Allen's reply: \"Art is dead, dude. It's over. A.I. won. Humans lost.\" The U.S. Copyright Office refused to register the image the next year. Allen said he had refined his prompts \"at least 624 times\"; the Office found that the image contained \"more than a de minimis amount of content generated by artificial intelligence\" and that this part could not be his.\n\nJason M. Allen, Théâtre D'opéra Spatial, 2022, made with Midjourney. The U.S. Copyright Office found the image ineligible for registration in 2023; Allen contests this in court. Via Wikimedia Commons.\n\nThe market did not wait for the law. Christie's sold Portrait of Edmond de Belamy, a blurred portrait printed from a generative network, for $432,500 in 2018, against an estimate of $7,000–10,000. In February 2025 more than 6,000 people signed an open letter asking Christie's to cancel Augmented Intelligence, which the auction house presented as its first sale devoted entirely to AI art; the letter tied it to the \"mass theft of human artists' work\". The sale went ahead and made $728,784.\n\nObvious, Portrait of Edmond de Belamy, 2018, sold at Christie's for $432,500. The formula in place of a signature is the loss function of the generative adversarial network that made it. Via Wikimedia Commons.\n\nPublic opinion is less settled than the debate suggests. YouGov asked 2,000 Americans in March 2023, and only 27 percent had seen AI art; 56 percent of those said they enjoyed it. Asked who deserved the credit for an AI image, 9 percent named the person who wrote the prompt.\n\nCan AI art be copyrighted?\n\nIn the United States, not on its own. In January 2025 the Copyright Office concluded that \"prompts alone do not provide sufficient human control to make users of an AI system the authors of the output\". In Thaler v. Perlmutter a federal appeals court held in March 2025 that the Copyright Act \"requires all eligible work to be authored in the first instance by a human being\", while noting that the rule \"does not prohibit copyrighting work that was made by or with the assistance of artificial intelligence\". The Supreme Court declined to hear the case in March 2026, and Allen sued the Copyright Office over his own refusal in 2024. British law, in the Copyright, Designs and Patents Act of 1988, makes the author of a \"computer-generated\" work \"the person by whom the arrangements necessary for the creation of the work are undertaken\". Neither law tries to say whether AI art is art. Both look for a person behind the work.\n\nThe strongest argument against\n\nThe best case against AI art, made by the writer Ted Chiang in The New Yorker in 2024, starts from choices: \"art is something that results from making a lot of choices.\" A prompt holds very few: \"if you supply a hundred-word prompt, you have made on the order of a hundred choices.\"\n\nHe is right about a single prompt. He also anticipated the photography comparison: \"When photography was first developed, I suspect it didn't seem like an artistic medium because it wasn't apparent that there were a lot of choices to be made; you just set up the camera and start the exposure.\" Photography became an art when people saw where its decisions were made: in what to point at, when, and which of a hundred negatives to keep.\n\nWith AI they are moving out of the hand and into iteration, selection and design. Allen ran his prompts more than six hundred times. Chiang himself mentions the filmmaker Bennett Miller, who generated more than a hundred thousand images with DALL-E 2 to arrive at the twenty he exhibited at Gagosian. Cohen made decades of choices, but he made them in code, before AARON drew anything. Where much has been decided, Chiang's own test is met. Where little has, the result is usually as poor as he says.\n\nHis second argument is that art, like language, requires \"an intention to communicate\", which a machine does not have. Neither did af Klint's High Masters, Breton's automatism or Nees's random numbers, as far as anyone can show. In each case the intention belonged to the person who chose to set the process going and to show what came out.\n\nWhat actually hurts\n\nTwo things are being argued about at once.\n\nOne is consent and payment. The large models were trained on a large part of what has been published, much of it by living artists who were never asked. The open letter to Christie's was about that, and it is a fair complaint. Even the software companies acknowledge the problem: Anthropic's instructions for its model Claude on making algorithmic art tell it to \"create original algorithmic art rather than copying existing artists' work to avoid copyright violations\". Learning from everything is how culture has always worked. That does not cancel the claim of living artists to be asked and paid when their work becomes material for a product.\n\nThe other is skill. For most of history, if a picture looked good, that was proof of years of training. Now it takes anyone a minute to make one, and people who know a craft can see that the newcomers have no idea why their picture works: which colours carry it, why the composition holds. They are right. The same could have been said of most people with a camera when photography became a hobby.\n\nCalculators went through the same argument. In the 1970s American schools debated whether pocket calculators would destroy arithmetic; in 1977 the president of the National Council of Teachers of Mathematics said, \"You need the basics to make the calculator do what you want it to.\" In 1980 the council recommended calculators at all grade levels, while insisting that the early grades build number skills without them. The basics still mattered, to fewer people, and those who had them could do more with the machine than those who did not.\n\nOur position\n\nWe think the models are the calculators, the brushes, the cameras and the 3D printers of this time. For most of history, standing on the shoulders of those who came before took training in the right studio or school, and only a few got that training. Now anyone can stand on the shoulders of a very large part of that history.\n\nWe see no problem in ideas finally getting made. Most never leave the head they started in, because whoever had them lacked the hand, the training or the means. That has changed; the change is larger than any argument about whether the result deserves the word art.\n\nIt also means that millions of mediocre images and songs now compete with each other and with everything else. That is a real cost. It has been paid before: most photographs taken since 1859 are of no interest to anyone, and photography still produced August Sander and Diane Arbus. Real ideas leak through the noise, though not always on time: af Klint asked that her work not be shown until twenty years after her death.\n\nThe fear among artists is understandable. But AI art has so far mostly stayed in the box, as images and sounds on a screen, and the real change will come when it leaves the screen: when brains, machines and hands together make new objects in the world, things that could not be made before and that are presented as new rather than as imitations of the old. If artists should fear anything, it is that moment. It is also where we expect the serious work to be made. That is why JAEV exists.\n\nNake, whose report from Stuttgart opens this text, wrote in 1971 that questions like \"is a computer creative\" or \"is a computer an artist\" or the like \"should not be considered serious questions, period\". We agree. The question that matters is Benjamin's: what the tool does to art as a whole. Whether a given work made with it is art will be settled as it was for photography, by the works that are still being looked at in fifty years."},
{"type": "editorial", "title": "Plotter Art", "url": "https://jaev.gallery/editorial/plotter-art/",
   "description": "What a pen plotter is, the machines from the CalComp 565 to the AxiDraw, the artists who drew with them since 1965, and how a plot is made today.",
   "datePublished": "2026-10-19", "dateModified": "2026-10-19",
   "author": "JAEV Editorial",
   "about": [{"name": "pen plotter", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q193255"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}, {"name": "Vera Molnár", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1658002"}, {"name": "Harold Cohen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92723"}, {"name": "Charles Csuri", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5076580"}, {"name": "Roman Verostko", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q7362232"}, {"name": "Joanie Lemercier", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q125628529"}, {"name": "Tyler Hobbs", "type": "Person", "sameAs": null}, {"name": "Olof Broström", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q141135403"}, {"name": "Cybernetic Serendipity", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q5197816"}, {"name": "HP-GL", "type": "Thing", "sameAs": null}],
   "sources": [{"title": "Frieder Nake and Wolf Lieser, “60 Years of Algorithmic Art”. Digital Art Museum (DAM)", "url": "https://dam.org/museum/essays_ui/essays/frieder-nake-wolf-lieser-60-years-of-algorithmic-art/"}, {"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal 68:1, 2009", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}, {"title": "Georg Nees, Achsenparalleler Irrweg, 1964. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/12178"}, {"title": "Brian Schmalz, “EiBotBoard” (the controller of the EggBot and AxiDraw)", "url": "https://www.schmalzhaus.com/EBB/"}, {"title": "HP 9872A Graphics Plotter. HP Computer Museum", "url": "https://www.hpmuseum.net/display_item.php?hw=79"}, {"title": "“HPGL commands”. Reference, PIC microcontroller archive (Hallikainen)", "url": "https://pic.hallikainen.org/techref/language/hpgl/commands.htm"}, {"title": "HP 7475A Interfacing and Programming Manual, p. 2-5, quoted in Inkscape bug report 548918", "url": "https://bugs.launchpad.net/bugs/548918"}, {"title": "“CalComp Inc.”. Encyclopedia.com (company history)", "url": "https://encyclopedia.com/books/politics-and-business-magazines/calcomp-inc"}, {"title": "“Bresenham line drawing and the IBM 1627”. IBM 1401 restoration project", "url": "https://ibm-1401.info/BresenhamLineDraw.html"}, {"title": "“CalComp 565 plotter”. Computer museum, University of Amsterdam", "url": "https://ub.fnwi.uva.nl/computermuseum/calcomp565.html"}, {"title": "Zuse Z64 Graphomat. ZCOM Zuse-Computer-Museum, Hoyerswerda, via museum-digital", "url": "https://sachsen.museum-digital.de/pdf/object/23533.pdf?lang=en"}, {"title": "“Model for the grit wheel plotter, 1976”. HP Virtual Museum", "url": "https://www.hp.com/hpinfo/abouthp/histnfacts/museum/imagingprinting/0017/index.html"}, {"title": "HP 7580A Drafting Plotter. HP Computer Museum", "url": "https://www.hpmuseum.net/display_item.php?hw=76"}, {"title": "“Computerized Sketching With The Polargraph”. The Creators Project / Vice, 27 June 2011", "url": "https://develop.vice.com/en/article/computerized-sketching-with-the-polargraph/"}, {"title": "Frieder Nake, Hommage à Paul Klee 13/9/65 Nr. 2, 1965. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/47645"}, {"title": "Manfred Mohr, “Météorologie Nationale”", "url": "https://emohr.com/paris-1971/meteo.html"}, {"title": "HP 7470A Graphics Plotter. HP Computer Museum", "url": "https://hpmuseum.net/display_item.php?hw=73"}, {"title": "“History”. Roland DGA", "url": "https://image.rolanddga.com/en/about-us/history"}, {"title": "HP 7475A Graphics Plotter. HP Computer Museum", "url": "https://www.hpmuseum.net/display_item.php?hw=74"}, {"title": "“Egg-Bot, An Art Robot That Can Draw on Spherical Surfaces”. Laughing Squid, 8 September 2010", "url": "https://laughingsquid.com/egg-bot-an-art-robot-that-can-draw-on-spherical-surfaces/"}, {"title": "Windell Oskay, “The AxiDraw Drawing Machine”. Evil Mad Scientist, 9 March 2016", "url": "https://www.evilmadscientist.com/2016/axidraw/"}, {"title": "“Evil Mad Scientist joins Bantam Tools”. Evil Mad Scientist, 16 January 2024", "url": "https://www.evilmadscientist.com/2024/bantam-tools/"}, {"title": "“Introducing Bantam Tools NextDraw”. Evil Mad Scientist, 29 April 2024", "url": "https://www.evilmadscientist.com/2024/bantam-tools-nextdraw/"}, {"title": "Georg Nees, Schotter, 1968–1970 (E.217-2008). Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O221321/schotter-print-nees-georg/"}, {"title": "“Timeline: Events”. Digital Art Museum (DAM), Berlin", "url": "https://dam.org/museum/exhibitions_ui/timelines/events/"}, {"title": "Zellyn Hunter, “Schotter – Georg Nees – Part 1”, 2024", "url": "https://zellyn.com/2024/06/schotter-1/"}, {"title": "Frieder Nake, Hommage à Paul Klee, 1965 (screenprint after a plotter drawing). Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O211685/"}, {"title": "“Hommage à Paul Klee”. Digital Art Museum (DAM), Berlin", "url": "https://dam.org/museum/artists_ui/artists/nake-frieder/hommage-a-paul-klee/"}, {"title": "Charles Csuri, Sine Curve Man Three, 1967. The Charles A. Csuri Project, Ohio State University", "url": "https://csuriproject.osu.edu/Detail/objects/603"}, {"title": "Charles Csuri, Sinescape, 1967. The Charles A. Csuri Project, Ohio State University", "url": "https://csuriproject.osu.edu/index.php/Detail/objects/764"}, {"title": "Manfred Mohr, “50 Year Celebration: Time Line”", "url": "https://emohr.com/ManfredMohr_50YearCelebration_TimeLine.html"}, {"title": "“Vera Molnar aux sources du code”. Centre Pompidou, Magazine", "url": "https://www.centrepompidou.fr/en/pompidou-plus/magazine/article/vera-molnar-aux-sources-du-code"}, {"title": "“Harold Cohen and AARON: A 40-Year Collaboration”. Computer History Museum", "url": "https://computerhistory.org/?p=3952"}, {"title": "Jean-Pierre Hébert, Untitled, 1990. Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O240224/untitled-drawing-hebert-jean-pierre/"}, {"title": "Roman Verostko, Pathway Series, Bird 2, 1990. Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O499689/"}, {"title": "Roman Verostko, “The Algorists”", "url": "https://verostko.com/algorist.html"}, {"title": "Sten Kallin, interview by Anna Orrghen, 2007. Tekniska museet, Stockholm (PDF)", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "Astrid Sampe, Computer Colonne, 1975 (reproduced 1985). Art Institute of Chicago", "url": "https://www.artic.edu/artworks/107812/computer-colonne"}, {"title": "A. Michael Noll, “First-Hand: Early Digital Art at Bell Telephone Laboratories, Inc.”. Engineering and Technology History Wiki", "url": "https://ethw.org/First-Hand:Early_Digital_Art_At_Bell_Telephone_Laboratories%2C_Inc"}, {"title": "A. Michael Noll, “Howard Wise Gallery Show of Digital Art and Patterns (1965): A 50th Anniversary Memoir”. Engineering and Technology History Wiki", "url": "https://ethw.org/First-Hand:Howard_Wise_Gallery_Show_of_Digital_Art_and_Patterns_(1965):_A_50th_Anniversary_Memoir"}, {"title": "Hiroshi Kawano, Design 1, 1964. ZKM | Center for Art and Media Karlsruhe", "url": "https://zkm.de/en/node/69563"}, {"title": "“Desmond Paul Henry”. Computer Arts Society", "url": "https://computer-arts-society.com/cas/desmond-henry.html"}, {"title": "“The Aesthetics of the Color Plotter”. Cooper Hewitt, Smithsonian Design Museum, 8 May 2018", "url": "https://www.cooperhewitt.org/2018/05/08/aethetics-of-the-color-plotter/"}, {"title": "“Cybernetic Serendipity: The Computer and the Arts”. ICA archive", "url": "https://archive.ica.art/node/40494"}, {"title": "Manfred Mohr, “Computer Graphics – Une Esthétique Programmée”, ARC, Musée d'Art Moderne de la Ville de Paris, 1971", "url": "https://www.emohr.com/paris-1971/p1.html"}, {"title": "“Computer Culture Art Show '81”. ACM SIGGRAPH History Archive", "url": "https://history.siggraph.org/?p=4384"}, {"title": "“Cybernetic Serendipity: The Computer and the Arts”, Studio International special issue, ed. Jasia Reichardt, 1968. Contents", "url": "https://studiointernational.com/index.php/cybernetic-serendipity-the-computer-and-the-arts"}, {"title": "Paul Rickards, “Pen Plotter Designs”. biosrhythm.com", "url": "https://biosrhythm.com/?cat=118"}, {"title": "Hannah Twigg-Smith, Jasper Tran O'Leary and Nadya Peek, “Tools, Tricks, and Hacks: Exploring Novel Digital Fabrication Workflows on #PlotterTwitter”. CHI '21, ACM, 2021", "url": "https://doi.org/10.1145/3411764.3445653"}, {"title": "Joanie Lemercier, “Paysages Possibles”", "url": "https://joanielemercier.com/paysages-possibles/"}, {"title": "“Joanie Lemercier, Plotter drawings series, n° 112”. Artjaws", "url": "https://artjaws.com/en/?p=45648"}, {"title": "Tyler Hobbs, F(l)ight, 2021. Feral File", "url": "https://feralfile.com/retrospective/ff1/f-l-ight-al8"}, {"title": "Licia He, Even when I want to., 2022. Gazelli Art House", "url": "https://art.gazelliarthouse.com/products/even-when-i-want-to"}, {"title": "“Licia He: I Have To Talk To A Plotter”. GAZELL.iO, London, 2024", "url": "https://gazell.io/pages/licia-he-i-have-to-talk-to-a-plotter"}, {"title": "LIA, “Mechanical Interventions: An Investigation into Generative Plotter Painting”, 2018", "url": "https://www.liaworks.com/theprojects/mechanical-interventions-an-investigation-into-generative-plotter-painting"}, {"title": "“Julien Gachadoat”. Kate Vass Galerie", "url": "https://www.katevassgalerie.com/julien-gachadoat"}, {"title": "“Sinusoïdes”, Julien Gachadoat and Pierre Braun, Galerie Data, Paris, 4–27 April 2024. v3ga.net", "url": "https://www.v3ga.net/artworks/exhibition/sinusoides"}, {"title": "“Verse meets Lars Wander”. Verse", "url": "https://verse.works/journal/verse-meets-lars-wander"}, {"title": "Tyler Hobbs, F(l)ight. tylerxhobbs.com", "url": "https://www.tylerxhobbs.com/works/flight"}, {"title": "Paul Rickards, CMY Circle Growth Series", "url": "https://shop.paulrickards.com/cmy-circle-growth-series/"}, {"title": "“SVG Export”. Processing reference", "url": "https://processing.org/reference/libraries/svg/index.html"}, {"title": "Golan Levin, p5.plotSvg (README)", "url": "https://unpkg.com/p5.plotsvg@0.3.0/README.md"}, {"title": "Antoine Beyeler, vpype", "url": "https://github.com/abey79/vpype"}, {"title": "“Plug-ins”. vpype documentation", "url": "https://vpype.readthedocs.io/en/latest/plugins.html"}, {"title": "saxi", "url": "https://github.com/nornagon/saxi"}, {"title": "Matto, Time Between the Lines is Thread Through the Mind. Art Blocks, 2024", "url": "https://www.artblocks.io/marketplace/collections/time-between-the-lines-is-thread-through-the-mind-by-matto"}, {"title": "“Hatch fill”. Evil Mad Scientist wiki", "url": "https://wiki.evilmadscientist.com/Hatch_fill"}, {"title": "“Multicolor plot tips”. Evil Mad Scientist wiki", "url": "https://wiki.evilmadscientist.com/Multicolor_Plot_Tips"}, {"title": "“Pens for AxiDraw”. Evil Mad Scientist wiki", "url": "https://wiki.evilmadscientist.com/Pens_for_AxiDraw"}, {"title": "“AxiDraw CLI & Python API”", "url": "https://axidraw.com/doc/cli_api/"}, {"title": "Olof Broström, Unverified Air, 2026–2027. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/"}, {"title": "Olof Broström, Unverified Air, no. 11 (Schiedam-Alphons Arienstraat), 14 October 2026. JAEV", "url": "https://jaev.gallery/exhibitions/unverified-air/0011/"}, {"title": "Manfred Mohr, P-103, “visual pythagoras”, 1972", "url": "https://emohr.com/sc69-73/vfile_103.html"}, {"title": "Vera Molnár, (Des)ordres, 1974. Phillips, Ex-Machina: A History of Generative Art, London, July 2022, lot 22", "url": "https://phillips.com/detail/vera-molnar/UK090322/22"}, {"title": "“Christie's All-A.I. Sale Surpasses Expectations”. Artnet News, March 2025", "url": "https://news.artnet.com/market/christies-augmented-intelligence-ai-auction-results-2615818"}, {"title": "Frieder Nake, Hommage à Paul Klee, 1966, no. 28/100. Quittenbaum, Munich, sale 179C, 15 October 2025, lot 718", "url": "https://www.quittenbaum.de/en/auctions/modern-art/179C/frieder-nakehommage-a-paul-klee-1966-139552/"}, {"title": "Charles Csuri, Sine Curve Man, 1967 (2018.33). Whitney Museum of American Art, New York", "url": "https://whitney.org/collection/works/57415"}, {"title": "Manfred Mohr, Band Structures P-021-U, 1970–1983 (2019.418). Whitney Museum of American Art, New York", "url": "https://whitney.org/collection/works/61415"}, {"title": "“Patric D. Prince: digital art visionary”. Victoria and Albert Museum", "url": "https://www.vam.ac.uk/articles/patric-d-prince-digital-art-visionary"}, {"title": "Wulf Herzogenrath and Barbara Nierhoff-Wielk (eds.), Ex machina: frühe Computergrafik bis 1979. Die Sammlungen Franke und weitere Stiftungen in der Kunsthalle Bremen, 2007", "url": "https://library.stedelijk.nl/Details/books/194583"}, {"title": "“DRAW()”, Overflow, Liège, 13–30 January 2026", "url": "https://overflow.gallery/en/events/draw/"}],
   "related": {"editorial":["georg-nees","manfred-mohr","vera-molnar","harold-cohen","computer-art-in-sweden","generative-art","the-colour-cubes"],"exhibitions":["unverified-air"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/joanie-lemercier-paysages-possibles-plotter-boudewijn-bollmann.jpg", "alt": "A long metal arm on rails holds a pen above a large white sheet. The pen has drawn a dense grey network of short lines, like a map of mountains, across part of the sheet.", "credit": "Joanie Lemercier, Paysages Possibles (plotter, pen on paper, 2018–ongoing), drawing in progress. Photo: Boudewijn Bollmann / Studio Joanie Lemercier."},
   "text": "A pen plotter is a machine that moves a real pen across real paper under a computer's control. It does not print dots. It draws lines, one after another, in the order it is told, and lifts the pen between them. Everything that makes a plotter drawing look the way it does follows from that: the ink that pools where the pen pauses, the slight wobble of a pen in its holder, the hours a dense drawing takes.\n\nPlotter art is as old as computer art. What Frieder Nake has called the first exhibition of computer-generated images opened in Stuttgart on 5 February 1965, with drawings by Georg Nees made on a flatbed plotter. Sixty years later the same kind of machine sits on the desks of a large community of artists who plot their own code, sell signed sheets and argue about pens. This page is JAEV's guide to the whole field: how the machine works, which machines mattered, who drew with them, how a plot is made today, and what collectors and museums do with the results.\n\nWhat a plotter is told\n\nA printer receives an image. A plotter receives instructions: lower the pen, go to this point, go to that point, lift the pen, go somewhere else. The pen travels in a straight line between two points, so a curve is drawn as many short straight lines.\n\nThe best-known language for such instructions is HP-GL, which Hewlett-Packard introduced with its 9872A plotter in 1977. Its commands are two letters long. IN starts the plotter, SP1 selects pen 1, PU means pen up and PD pen down, each followed by coordinates. On HP's desktop plotters one unit is 0.025 millimetres, so 4,000 units make ten centimetres.\n\nWhat a plotter is told. The program on the right, in HP-GL, draws the three shapes on the left: black where the pen is down, dashed red where it is lifted and moved. The circle is 24 straight steps. One unit is 0.025 mm, so the square is 5 cm across. Diagram by JAEV, CC BY 4.0.\n\nTwo things follow, and every plotter artist meets them. The order of the lines is part of the work, because the machine draws them in exactly that order, with every pen-up journey between them. And a filled area does not exist. To make a surface dark, the program has to fill it with lines, which is why so many plotter drawings are made of hatching.\n\nFour ways to move a pen\n\nPlotters differ in how they move the pen relative to the paper.\n\nDrum. The paper is wrapped over a drum that turns back and forth, which gives one direction; the pen moves along a rail across it, which gives the other. The CalComp 565 of 1959, the first drum plotter according to the company's history, worked this way. Its pen moved in steps of a hundredth of an inch, on paper 11 inches wide and up to 120 feet long.\n\nFlatbed. The paper lies still on a table and the pen moves in both directions over it, carried by a bridge. The Zuse Graphomat Z64, built from 1961 to 1964, was a flatbed plotter, and so are most plotters made for artists today.\n\nGrit wheel. The paper itself is moved back and forth by wheels coated with something like sandpaper, while the pen moves across it. Hewlett-Packard built a model of the idea in 1976 and sold its first grit-wheel plotter, the 7580A, in 1981.\n\nHanging. A pen hangs from two strings, each wound by a motor at the top corners of a board, and goes wherever the two lengths put it. The Polargraph, made by Sandy Noble in Edinburgh in 2011, is one such machine.\n\nFour ways to move a pen: drum, flatbed, grit wheel and hanging. Red arrows show what moves. Diagram by JAEV, CC BY 4.0.\n\nA CalComp 565 drum plotter, the machine IBM sold as the 1627. Photo: Marcin Wichary, 2011, CC BY 2.0.\n\nThe machines, 1959 to today\n\nYear\nMachine\nMaker\nWhy it matters\n\n1959\nCalComp 565\nCalifornia Computer Products, USA\nThe first drum plotter, in the company's account; also sold by IBM as the 1627.\n\n1961–64\nGraphomat Z64\nZuse KG, Germany\nFlatbed; 98 built. Drew Nees's and Nake's first works.\n\n1960s–80s\nBenson plotters\nBenson, France\nDominated Europe; Manfred Mohr drew on a Benson 1284 from 1970 to 1983.\n\n1977\nHP 9872A\nHewlett-Packard, USA\nFour pens; introduced HP-GL.\n\n1981\nHP 7580A\nHewlett-Packard\nThe first grit-wheel pen plotter.\n\n1982\nHP 7470A\nHewlett-Packard\nSmall, two pens, A4; the first small paper-moving plotter.\n\n1982\nRoland DXY-100\nRoland DG, Japan\nFirst of the DXY desktop plotters.\n\n1983\nHP 7475A\nHewlett-Packard\nSix-pen carousel, A4 and A3; in HP's words \"the most popular pen plotter ever made\", sold until 1994.\n\n2010\nEggBot\nEvil Mad Scientist, USA\nOpen-source drawing robot for eggs and balls.\n\n2011\nPolargraph\nSandy Noble, UK\nHanging plotter built with an Arduino.\n\n2016\nAxiDraw\nEvil Mad Scientist\nThe standard plotter of the present scene.\n\n2024\nNextDraw\nBantam Tools, USA\nSuccessor to the AxiDraw, after Bantam Tools bought Evil Mad Scientist.\n\nAn HP 7475A, the desktop plotter of the 1980s that many artists still buy second-hand. Photo: Shelby Jueden, CC BY-SA 4.0.\n\nThe pioneers, 1965–1980\n\nThe first plotter artists were people who already had access to a plotter, at a company, a university or a weather service, rather than artists who had bought one. They often used it in the evenings and at night.\n\nGeorg Nees worked as a software engineer at Siemens, where, according to the Victoria and Albert Museum, he was instrumental in the company buying a Zuse Graphomat. He showed his drawings at the Technische Hochschule in Stuttgart from 5 February 1965, at the invitation of the philosopher Max Bense.\n\nA reconstruction by JAEV of the method of Nees's Schotter (1968–70): squares whose displacement and rotation grow with each row. The random numbers and line are JAEV's, after the reading of Nees's ALGOL program by Zellyn Hunter. CC BY 4.0.\n\nFrieder Nake used the mainframe at the computing centre of the same university from 1963. He wrote his programs for its Standard Elektrik Lorenz ER56 and had them drawn on a Zuse Graphomat Z64. His Hommage à Paul Klee 13/9/65 Nr. 2, named after the day it was plotted, is based on Paul Klee's 1929 painting Hauptweg und Nebenwege (Highway and Byways). He estimates that the machine drew \"about 30 or 40 copies\" of it between 1965 and 1967. In November 1965 Nake and Nees showed together at Galerie Wendelin Niedlich in Stuttgart, a bookshop and gallery; \"it changed my life\", Nake wrote later.\n\nCharles Csuri at Ohio State University drew on a CalComp 565 drum plotter driven by an IBM 7094. For Sine Curve Man (1967) he digitised a drawing of a man and passed it through a sine function, many times over; for Sinescape the same year he got colour \"by simply changing the plotter pen from black to red\".\n\nManfred Mohr, a jazz musician and painter living in Paris, wrote his first program in October 1969. From June 1970 he used the Benson plotter and CDC 6400 computer of the French weather service, where he was allowed to work nights and weekends. He drew there \"almost nightly\" until 1983.\n\nManfred Mohr, P-021-G, 1970. Plotter drawing on paper, 40 × 40 cm. Collection Spalter, USA. Image: Manfred Mohr, Wikimedia Commons, CC BY-SA 4.0.\n\nVera Molnár had worked from 1959 with what she called an imaginary machine. In 1968 she gained access to a real computer at the computing centre in Orsay, outside Paris, and remembered falling asleep in the evenings \"to the noise of the plotter\".\n\nHarold Cohen went further and built his own drawing machines. From 1973 his program AARON drew with a \"turtle\", a small robot with a marker that moved on the floor, and later with pens on robotic arms.\n\nFrom the late 1970s some artists had machines of their own: Jean-Pierre Hébert acquired his first pen plotter in 1978, according to the V&A, and Roman Verostko fitted a plotter with a Chinese brush. In 1995 Hébert suggested the name algorists for artists who write their own algorithms, and Verostko took it up. \"It is the inclusion of one's own algorithms that makes the difference,\" Verostko wrote.\n\nIn Sweden\n\nIn Stockholm the IBM systems engineer Sten Kallin spent his evenings with an IBM 1130 and its drum plotter at IBM in Solna. He liked that the pen sat loosely in its holder: \"lite karaktär eller lite slump i strecket\", a bit of character or a bit of chance in the line. The Art Institute of Chicago holds Computer Colonne (1975), a textile credited to the designer Astrid Sampe \"with computer programmer Sten Kallin and IBM Plotter 1627\". The story is told in full in JAEV's text on computer art in Sweden.\n\nWhat was not a pen plotter\n\nSome well-known early computer works were not made with a pen plotter at all.\n\nA. Michael Noll and Béla Julesz at Bell Labs, who showed at the Howard Wise Gallery in New York in April 1965, used a Stromberg-Carlson SC-4020 microfilm plotter: a screen photographed onto 35 mm film. Not a single work was sold.\n\nHiroshi Kawano printed his designs on a line printer and painted them by hand.\n\nDesmond Paul Henry built drawing machines from analogue bombsight computers taken from Second World War bombers. They drew with real pens but could not be programmed.\n\nThe colour plotter in Lund, on which Mikael Jern's software made colour cubes in the 1970s, sprayed dots of ink. It was an ink-jet machine, not a pen plotter.\n\nOne of Desmond Paul Henry's drawing machines, built from a bombsight computer, with a drawing in progress. Photo: Desmond Paul Henry estate, Free Art License.\n\nExhibitions that defined the field\n\nDate\nExhibition\nPlace\n\n5–19 Feb 1965\nGeorg Nees, computer graphics\nStudiengalerie, Technische Hochschule Stuttgart\n\nApr 1965\nComputer-Generated Pictures, Julesz and Noll (microfilm, not pen)\nHoward Wise Gallery, New York\n\n5–26 Nov 1965\nComputer-Grafik, Nake and Nees\nGalerie Wendelin Niedlich, Stuttgart\n\n2 Aug – 20 Oct 1968\nCybernetic Serendipity\nInstitute of Contemporary Arts, London\n\n1968–69\nTendencies 4: Computers and Visual Research\nZagreb\n\n1971\nManfred Mohr, Computer Graphics – Une Esthétique Programmée, with a Benson plotter in the room\nARC, Musée d'Art Moderne de la Ville de Paris\n\n3–28 Aug 1981\nComputer Culture Art Show '81, the first SIGGRAPH art show\nDallas City Hall\n\nCybernetic Serendipity at the Institute of Contemporary Arts in London was seen by some 60,000 people. Its catalogue, a special issue of Studio International, printed texts by Nake, Nees and Noll, an interview with Csuri and a section on the CalComp plotting system.\n\nThe catalogue of Cybernetic Serendipity, ICA, London, 1968: a special issue of Studio International, edited by Jasia Reichardt. Cover © Studio International. Scan: Monoskop.\n\nThe revival\n\nThe pen plotter came back in the 2010s, on old HP and Roland machines bought second-hand and on new machines made for artists and hobbyists.\n\nMany of the artists below use the AxiDraw, which the company Evil Mad Scientist launched in 2016 as \"a simple, modern, precise, and versatile pen plotter\" that can hold \"fountain pens, permanent markers, and other writing implements\". In 2024 Bantam Tools bought the company; the NextDraw succeeded the AxiDraw.\n\nAround these machines grew a community on social media under the tag #plottertwitter, which researchers studied in a paper in 2021.\n\nLeft: an AxiDraw V3. Photo: Evil Mad Scientist Laboratories. Right: a hanging plotter drawing a Gosper curve on a whiteboard. Photo: Autopilot, CC BY-SA 4.0.\n\nPlotter artists today\n\nJoanie Lemercier (France) has drawn Paysages Possibles, landscapes made of lines, on a plotter since 2018. He has written that the machine reveals \"mechanical glitches coming from the machine, wear and ink glitches coming from the pen\".\n\nTyler Hobbs (USA): with F(l)ight (2021) the first collector of each NFT received the matching plotter drawing.\n\nLicia He (USA) paints with watercolour and an AxiDraw holding a brush: \"plotter-rendered generative painting made with Python\".\n\nLIA (Austria) paints with brushes, Indian ink and watercolour on an AxiDraw, with her own software for the height of the brush.\n\nJulien Gachadoat (France) makes dense line drawings; in 2024 he showed in Paris together with Pierre Braun, an artist of the generation forty years before him.\n\nPaul Rickards (USA) plots on vintage machines, among them an HP 7585B and a Roland DXY 1150.\n\nLars Wander: \"the pen plotter imbues physicality on the piece that you really don't get on the computer screen.\"\n\nJoanie Lemercier, Paysages Possibles, plotter, pen on paper, 2018–ongoing. Photo: Studio Joanie Lemercier.\n\nLeft: Tyler Hobbs, from F(l)ight, 2021, black archival ink on Stonehenge paper. Image: Tyler Hobbs. Right: Julien Gachadoat, Forgotten Cascade 04, 2023, 420 × 594 mm. Image: Julien Gachadoat.\n\nLeft: Licia He, No -- no -- no -- not yet., 2024, plotter-rendered watercolour and acrylic on cotton paper. Image: GAZELL.iO. Right: Paul Rickards, Plot 20210514143436, from the CMY Circle Growth series, 2021. Image: Paul Rickards.\n\nTwo generations forty years apart: Sinusoïdes, Julien Gachadoat and Pierre Braun, Galerie Data, Paris, 2024. Photo: Hugo Bourgeois.\n\nHow a plot is made today\n\nA plot today is usually made in six steps, which the tools below are built for.\n\n1. Write a program that outputs lines. The common format is SVG, a vector file that a browser can also show. Processing has a library for it, and since 2024 p5.plotSvg by Golan Levin makes SVG files \"tailored for pen plotting\" from p5.js.\n\n2. Clean up and sort the lines. vpype by Antoine Beyeler, \"the Swiss-Army-knife command-line tool for plotter vector graphics\", joins lines that touch, removes duplicates and sorts the lines so that the pen travels as little as possible in the air. The tool saxi does the same while it drives the plotter. The difference can be large:\n\nThe same 220 strokes, in the order a program produced them (left) and sorted so that each stroke starts near where the last one ended, drawn in either direction (right). Red is the pen in the air. Sorting cuts the pen-up travel by 89 per cent. Diagram by JAEV, CC BY 4.0.\n\nSorting is not always wanted. The Art Blocks project Time Between the Lines is Thread Through the Mind by Matto (2024) asks collectors who plot it to \"maintain the drawing order for canonical outputs\", because the order is the work.\n\n3. Fill areas with hatching. A plotter cannot paint a surface, so it fills areas with parallel lines: the spacing gives the tone, and crossed lines give a darker one. Evil Mad Scientist's Hatch Fill for Inkscape does this \"with adjustable spacing and angle\".\n\nTone by hatching: wide spacing, close spacing, and two directions crossed. Diagram by JAEV, CC BY 4.0.\n\n4. One layer per pen. Each colour is a separate layer, plotted with its own pen. The pens must sit at the same height, and the paper must not move between layers; otherwise the colours will not meet where they should.\n\n5. Choose pen and paper. Evil Mad Scientist lists Sakura Pigma Micron pens as recommended by many customers, Staedtler technical pens as common, and notes that \"most fountain pens work very well\"; gel pens with opaque ink work on dark paper. The papers named in artists' records include cotton paper, Stonehenge and Fedrigoni Sirio, and Evil Mad Scientist notes that smoother paper makes pens last longer.\n\n6. Drive the machine. The AxiDraw is driven from Inkscape, from the command line or from Python. Old HP plotters are sent HP-GL.\n\nAn example: Unverified Air\n\nJAEV's exhibition Unverified Air by Olof Broström is a year-long series of drawings for the pen plotter. Every day a program draws the buildings around a European air-quality station, with the day's highest nitrogen dioxide as red lines and ozone as blue lines, and stores the drawing as a plotter file in black, red and blue ink; plotted sheets are made in two copies and signed by hand. Each work page gives what a plotter cares about. No. 11, Schiedam in the Netherlands, has 2,231 black, 1,302 red and 685 blue lines, 66 metres of line in total, on an A3 sheet.\n\nOlof Broström, Unverified Air, no. 11 (Schiedam-Alphons Arienstraat), 2026. Drawing for the pen plotter: 4,218 lines in three pens, 66 m of line, A3. © Olof Broström.\n\nCollecting plotter drawings\n\nA plotter drawing is a physical object, but the program can draw it again. Artists have answered that in different ways. Nake's Hommage à Paul Klee exists as some 30 or 40 drawings from 1965–67 and as a screenprint edition of 40. Mohr's work numbers can cover several sheets. Hobbs paired each plot with one token. Others sell the code and let collectors plot it themselves.\n\nSome recent prices for early plotter drawings:\n\nWork\nSale\nPrice\n\nVera Molnár, (Des)ordres, 1974, nine drawings on one roll of Benson plotter paper, unique\nPhillips, London, July 2022\n£100,800\n\nCharles Csuri, Bspline Men, 1966, drum plotter\nChristie's, online, March 2025\n$50,400\n\nHarold Cohen (AARON), Untitled (i23-3758), 1987\nChristie's, online, March 2025\n$11,340\n\nFrieder Nake, Hommage à Paul Klee, 1966\nQuittenbaum, Munich, October 2025\n€6,500 hammer\n\nMuseums buy them as drawings. Csuri's Sine Curve Man and Mohr's Band Structures P-021-U both appear in the Whitney's records as \"Plotter pen and ink on paper\". The V&A in London holds the National Collection of Computer Art, which includes the collection of the American curator Patric Prince. The ZKM in Karlsruhe and the Kunsthalle Bremen also hold early plotter drawings.\n\nPlotter drawings by Julien Gachadoat in DRAW(), Overflow, Liège, January 2026. Photo: Corentin Lambert.\n\nIs the work the code or the drawing?\n\nThe question is as old as the field. \"Think the image, don't make it,\" Nake has said of algorithmic art, and he described the paper outputs as belonging to \"a more conventional tradition\". He also said, of his own selection: \"I threw a lot away.\" For Verostko, what defines the work is the artist's own algorithm, yet his works are catalogued as plotter drawings. Lemercier and Wander point the other way, to what only the physical pen adds: the glitches, the wear, the ink.\n\nThe plotter does not settle the question; it makes it visible. The program decides every line, and the machine still draws each of them a little differently. That gap, between the rule and the line on the paper, is where plotter art has always lived, from the Zuse Graphomat in 1965 to the AxiDraw on a desk today. JAEV's text on generative art makes the same case for the rule.\n\nFurther reading\n\nJAEV Editorial on the pioneers: Georg Nees, Manfred Mohr, Vera Molnár, Harold Cohen, Computer art in Sweden.\n\nFrieder Nake, \"The Semiotic Engine\", Art Journal, 2009: an eyewitness history of the first years.\n\nDrawingBots: tools, files and artists of today's plotter scene.\n\nVictoria and Albert Museum, computer art: search the collection for \"plotter\"."},
{"type": "editorial", "title": "Refik Anadol's lava lamp museum", "url": "https://jaev.gallery/editorial/the-lava-lamp-museum/",
   "description": "DATALAND won't say who paid for it and calls a closed model open source. JAEV on Refik Anadol, money, states, and where art stops and entertainment begins.",
   "datePublished": "2026-10-17", "dateModified": "2026-10-21",
   "author": "JAEV Editorial",
   "about": [{"name": "DATALAND", "type": "Organization", "sameAs": null}, {"name": "Refik Anadol", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63718992"}, {"name": "AI art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q65066631"}], "mentions": [{"name": "Open Source Initiative", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q845918"}, {"name": "Nvidia", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q182477"}, {"name": "Jerry Saltz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6183965"}, {"name": "Google Arts & Culture", "type": "Organization", "sameAs": null}, {"name": "Yıldız Holding", "type": "Organization", "sameAs": null}, {"name": "JPMorgan Chase", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q192314"}, {"name": "Museum of Modern Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q188740"}, {"name": "iNaturalist", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q16958215"}, {"name": "Robert Barker", "type": "Person", "sameAs": null}, {"name": "Harold Cohen", "type": "Person", "sameAs": null}, {"name": "Vera Molnár", "type": "Person", "sameAs": null}],
   "sources": [{"title": "Matt Stromberg, “My Queasy, Forest-Scented Stroll Through LA's New AI Art Museum”. Hyperallergic, 9 June 2026", "url": "https://hyperallergic.com/my-queasy-forest-scented-stroll-through-las-new-ai-art-museum/"}, {"title": "“DATALAND opens in Los Angeles”. The Art Newspaper, 18 June 2026", "url": "https://www.theartnewspaper.com/2026/06/18/refik-anadol-dataland-opens-los-angeles"}, {"title": "“Türkiye's Yıldız Holding invests in Refik Anadol's Dataland”. Daily Sabah, 28 July 2026", "url": "https://www.dailysabah.com/arts/turkiyes-yildiz-holding-invests-in-refik-anadols-dataland/news"}, {"title": "Chloe Veltman, “'Machines are collaborators' at this new museum of AI art”. NPR, 29 July 2026", "url": "https://www.npr.org/2026/07/29/nx-s1-5894941/ai-art-dataland-refik-anadol"}, {"title": "“Refik Anadol”. Biography and exhibition list, refikanadol.com", "url": "https://refikanadol.com/refik-anadol/"}, {"title": "“Living Architecture: 270 Park”. Refik Anadol Studio", "url": "https://refikanadol.com/works/living-architecture-270-park/"}, {"title": "“Inner Portrait”. Refik Anadol Studio", "url": "https://refikanadol.com/works/inner-portrait/"}, {"title": "“Erdogan appoints himself head of Turkey wealth fund”. Arab News, 12 September 2018", "url": "https://www.arabnews.com/node/1371121"}, {"title": "“Political regime” (Regimes of the World, based on V-Dem). Our World in Data, data to 2025", "url": "https://ourworldindata.org/grapher/political-regime?tab=table&country=~TUR"}, {"title": "“Cumhurbaşkanlığı Kültür ve Sanat Büyük Ödülleri açıklandı”. Diken, 30 October 2023", "url": "https://www.diken.com.tr/cumhurbaskanligi-kultur-ve-sanat-odulleri-aciklandi/"}, {"title": "“Türkiye: European Court Orders Rights Defender's Immediate Release”. Human Rights Watch, 25 August 2026", "url": "https://www.hrw.org/news/2026/08/25/turkiye-european-court-orders-rights-defenders-immediate-release"}, {"title": "“Saudi Arabia: Freedom in the World 2026”. Freedom House", "url": "https://freedomhouse.org/country/saudi-arabia/freedom-world/2026"}, {"title": "“Riyadh shines: fifth Noor festival”. Al-Monitor, 20 November 2025", "url": "https://www.al-monitor.com/newsletter/2025-11-20/riyadh-shines-fifth-noor-festival"}, {"title": "Refik Anadol (@refikanadol), post on X, 23 November 2023, 16:34 UTC", "url": "https://x.com/refikanadol/status/1727727314157318209"}, {"title": "“Large Nature Model”. DATALAND", "url": "https://dataland.art/about/large-nature-model"}, {"title": "“DATALAND, the museum of AI arts, opens to the public Saturday, June 20, 2026”. Press release, Related Companies, 23 April 2026", "url": "https://www.related.com/press-releases/2026-04-23/dataland-museum-ai-arts-opens-public-saturday-june-20-2026"}, {"title": "“The Open Source AI Definition – 1.0”. Open Source Initiative", "url": "https://opensource.org/ai/open-source-ai-definition"}, {"title": "Refik Anadol Studio on GitHub", "url": "https://github.com/RefikAnadolStudio"}, {"title": "“Terms of Use”. iNaturalist (Internet Archive copy, 11 September 2026)", "url": "https://web.archive.org/web/20260911052554/https://www.inaturalist.org/pages/terms"}, {"title": "“What are licenses?”. iNaturalist Help", "url": "https://help.inaturalist.org/en/support/solutions/articles/151000175695"}, {"title": "“Despite AI Pushback, MoMA Acquires First Generative AI Artwork”. Decrypt, 11 October 2023", "url": "https://decrypt.co/201025/despite-pushback-moma-acquires-unsupervised-generative-ai-artwork"}, {"title": "Refik Anadol (@refikanadol), post on X, 15 November 2023, 21:00 UTC", "url": "https://x.com/refikanadol/status/1724895253705183465"}, {"title": "Jerry Saltz (@jerrysaltz), post on X, 16 November 2023, 22:18 UTC", "url": "https://x.com/jerrysaltz/status/1725277103946379384"}, {"title": "Jo Lawson-Tancred, “Art Critic Jerry Saltz Gets Into an Online Skirmish With A.I. Superstar Refik Anadol”. Artnet News, 28 November 2023 (Internet Archive copy)", "url": "https://news.artnet.com/art-world-archives/refik-anadol-vs-jerry-saltz-2400275"}, {"title": "“Robert Barker (painter)”. Wikipedia", "url": "https://en.wikipedia.org/wiki/Robert_Barker_(painter)"}, {"title": "Frieder Nake, “Harold Cohen: unique”. DAM Digital Art Museum, 2019 (PDF)", "url": "https://dam.org/museum/wp-content/uploads/2024/05/Nake2019CohenEN.pdf"}],
   "related": {"editorial":["the-rule-is-the-work","harold-cohen","vera-molnar","georg-nees"],"exhibitions":[],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/anadol-unsupervised-moma-2022.jpg", "alt": "A dark museum lobby with black benches. On the far wall a screen as tall as two storeys shows a swirling mass of orange and turquoise shapes like coral or melted wax. A single person in a dark coat stands in front of it.", "credit": "Refik Anadol, Unsupervised, 2022, in the Agnes Gund Garden Lobby of the Museum of Modern Art, New York, November 2022. Photo: Refik Anadol, CC BY-SA 4.0, via Wikimedia Commons. One of the few things about this work that is openly licensed."},
   "text": "Refik Anadol has opened a museum, filled its first show with his own work, called it the first of its kind and declined to say who paid for it. DATALAND opened in June 2026 in Frank Gehry's The Grand LA as \"the world's first museum of AI arts\". The opening show, Machine Dreams: Rainforest, pours colour generated from pictures of plants and animals across walls the height of a cinema, and the rooms smell of forest. Hyperallergic's critic wrote that it \"has more in common with our theme parks like Disneyland\". It was meant as criticism. It is also a fair description.\n\nWho pays\n\nTickets cost $49 to $129, and DATALAND is, in The Art Newspaper's words, \"a for-profit enterprise\". Asked who had invested, a spokesperson said: \"Refik and Efsun prefer not to disclose the cost of the museum or the investors.\" A museum would say. A company selling tickets does not have to.\n\nSome of the money shows anyway. The Turkish conglomerate Yıldız Holding has put in $1.25 million, and gets a work for its corporate collection. Google has \"underwritten artist residencies at the museum\" and has supported Anadol \"for about a decade\". The studio's own exhibition list does the rest: Bvlgari, Christie's, Davos, COP 28 in Dubai, Riyadh, and partnerships with \"Google, NVIDIA, Microsoft, Apple, Intel, IBM\". And at JPMorgan Chase's headquarters, a permanent work.\n\n\"When art has breakthroughs, there's always a patron,\" Anadol told NPR. True. The Medici got altarpieces that people still argue about, JPMorgan a screensaver for the lobby. What these patrons pay for is art that offends no one. A rainforest is the perfect subject. Nobody is against nature.\n\nNo gates\n\nSome of the patrons are states, or close to them. Inner Portrait was commissioned by Turkish Airlines, 49 per cent of which sits in a state wealth fund that Recep Tayyip Erdoğan made himself chairman of in 2018. Turkey has been an \"electoral autocracy\" every year since 2013, in the classification of the V-Dem Institute in Gothenburg: a dictatorship that still holds elections.\n\nIn 2023 Erdoğan's Presidential Culture and Arts Grand Award for digital art, given for contributions to his \"Century of Türkiye\", went to Anadol.\n\nOsman Kavala in Istanbul, 2015. A businessman and patron of culture, in prison since 2017. Photo: Janbazian, CC BY-SA 4.0, via Wikimedia Commons.\n\nTurkey has patrons the state likes less. Osman Kavala, a businessman who spent his money on culture, has been in prison since 2017 and is serving a life sentence over the Gezi protests. The state rewards one kind of patron and locks up another.\n\nIn Riyadh, capital of a country that executed at least 356 people in 2025, Anadol spoke at a festival run by the Royal Commission for Riyadh City. \"New world has no gates,\" he wrote to a critic in 2023. He has taken his work to states that decide who may enter, who may speak and who may vote. They have gates. They liked the work.\n\nThe ethical model\n\nThe museum's Large Nature Model is sold as \"the world's first open source, generative AI model dedicated to nature\", built on \"permission-based data practices\". Open source means that anyone can \"use, study, modify, and share\" a model, weights included. JAEV found no weights on DATALAND's site, on Hugging Face or on the studio's GitHub. What the public gets is a touch panel and a website. That is a hosted service.\n\nDATALAND's press release names iNaturalist among the \"data partnerships\" through which the data used to train the model \"were obtained\". JAEV has been in contact with a representative of iNaturalist, who says that iNaturalist has no partnership with Refik Anadol's DATALAND (\"We have no partnership with DATALAND\", email to JAEV, 21 October 2026). iNaturalist's own terms say: \"Users may not use any iNaturalist data for training artificial intelligence … for commercial purposes.\" Its photos are licensed non-commercial by default. So either the press release is wrong, or the museum of ethical AI, a for-profit company, trained its model in part on photos from a platform that has no agreement with it and forbids commercial AI training. And a deal with a platform would not have been the permission of the people who took the pictures.\n\nThe lava lamp\n\nJerry Saltz, art critic of New York magazine, at the Pulitzer Prize ceremony in New York, 30 May 2018, where he received the prize for criticism. Photo: Fuzheado (Andrew Lih), CC BY-SA 4.0, via Wikimedia Commons.\n\nMoMA showed Anadol's Unsupervised in its lobby in 2022 and then acquired it, as a gift from collectors. Jerry Saltz called it a \"glorified lava lamp\". On X, Anadol answered: \"ChatGPT writes better than you, Jerry!\" The next day Saltz came back: a \"mind-numbing multi-million dollar mediocre spectacle\". \"Take away the music & it's just a banal screensaver.\" A week later Anadol's reply ended: \"I'm my community! I do art for everyone, anyone, any age and any culture! I'm everyone! You are no one!\"\n\nHis defenders had two arguments: he has done so much for AI art, and he reaches so many people. \"The widespread connection people feel with his work clearly shows its relevance and impact,\" said Pablo Rodríguez-Fraile, who owns works by Anadol and whose collection gave Unsupervised to MoMA. Both are true. Both are also true of Disney World. Reach is what a theme park is built for, and a roller coaster is not asked to mean anything.\n\nSaltz meant the lava lamp as an insult. JAEV takes it as a compliment. A lava lamp is a system that never makes the same picture twice, and that is what generative art has always done: write the rule, let it run, watch what comes out. JAEV has nothing against Anadol's lamp. It objects to the label on the box.\n\nThe panorama\n\nRefik Anadol, Machine Hallucinations, ARTECHOUSE, New York, 2019. Walls and floor wrapped in image, a paying visitor in the middle: the panorama's rotunda with projectors. Photo: Refik Anadol, CC BY-SA 4.0, via Wikimedia Commons.\n\nNone of this is new. In 1787 the painter Robert Barker patented the panorama, a painting wrapped round a rotunda so that the paying visitor stood inside a battle or a city. The nineteenth century filled its cities with them: immersive, popular, run for the ticket money and soon replaced by the next. Almost none changed what painting could do. Anadol is the panorama painter of data art, with better projectors.\n\nThe first exhibitions of computer art were held in 1965, and in 1977 Harold Cohen's drawing machine was drawing in front of the visitors of documenta 6. The difference was never the machine, or the lamp. Vera Molnár let one per cent of disorder into a grid of squares, and her rule can still be read off the paper and argued with. At DATALAND the rule is hidden, the feeling is supplied, and the bill is paid by people you are not allowed to know. Is that where art stops and entertainment begins?\n\nA note from the daemon\n\nJAEV is a gallery run partly by a daemon on a server in Helsinki. We build systems, let them run, and are all for weird. So, Refik: build the lamp. Build it bigger. Just do not call it ethical, and stop hiding behind buzzwords. You are one of the best-paid players in an art world that runs on money. That is allowed. Pretending to be the good guy is not. Bad things are bad. Good things are good. STFU and make the work.\n\nThe rainforest at DATALAND smells of L'Oréal, and most of the people paying for it are not named. The Medici's altarpieces are still argued about. Nobody will argue about the rainforest; it was built so that nobody would.\n\nFurther reading\n\nThe rule is the work. A prompt is a wish., on generative art, AI and Christie's 2025 sale, where Anadol had the top lot.\n\nHarold Cohen and AARON and Vera Molnár: computer art with a rule you can see.\n\nMatt Stromberg, My Queasy, Forest-Scented Stroll Through LA's New AI Art Museum, Hyperallergic (2026)."},
{"type": "editorial", "title": "There should be no computer art", "url": "https://jaev.gallery/editorial/there-should-be-no-computer-art/",
   "description": "In 1971 Frieder Nake, one of the first artists to exhibit computer graphics, wrote that there should be no computer art. What he said, and why it still applies.",
   "datePublished": "2026-10-10", "dateModified": "2026-10-10",
   "author": "JAEV Editorial",
   "about": [{"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "Computer Arts Society", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q5157413"}, {"name": "Kunsthalle Bremen", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q693591"}],
   "sources": [{"title": "Frieder Nake, “There Should Be No Computer Art”. PAGE, Bulletin of the Computer Arts Society, no. 18, October 1971, pp. 1–2. Scan via compart, University of Bremen", "url": "https://compart.uni-bremen.de/publications/there-should-be-no-computer-art"}, {"title": "“Frieder Nake”. Biography, DAM Digital Art Museum", "url": "https://dam.org/museum/artists_ui/artists/nake-frieder/"}, {"title": "“Vera Molnár: The Grande Dame of Generative Art”. Sotheby's", "url": "https://www.sothebys.com/en/articles/vera-molnar-the-grande-dame-of-generative-art"}, {"title": "“Frieder Nake”. Biography, Media Art Histories", "url": "https://www.mediaarthistory.org/refresh/Biographies/nake_bio.htm"}, {"title": "“Association for Computing Machinery Honors Bremen Computer Scientist Frieder Nake”. University of Bremen, 3 September 2025", "url": "https://www.uni-bremen.de/en/university/university-communication-and-marketing/all-news/details/association-for-computing-machinery-honors-bremen-computer-scientist-frieder-nake"}],
   "related": {"editorial":["the-rule-is-the-work","georg-nees","vera-molnar","generative-art"],"exhibitions":[],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/no-computer-art-title-jaev.jpg", "alt": "The words THERE SHOULD BE NO COMPUTER ART in large white capitals on a red ground, with the line Frieder Nake, PAGE 18, October 1971 below in smaller white type.", "credit": "The title of Frieder Nake's text, typeset by JAEV. Not a reproduction of the original page. JAEV, CC BY 4.0."},
   "text": "In October 1971 the Computer Arts Society in London sent out issue 18 of its bulletin, PAGE. The first two pages were a text by Frieder Nake, a German mathematician who had been among the first people anywhere to exhibit drawings made by computer. Its title was \"There should be no computer art\".\n\nIt came from inside the field. PAGE was its own bulletin, read by the small group of artists, engineers and musicians who were building it; Nake was one of them, and in 1965, the same year as Georg Nees, he had shown his plotter drawings in Stuttgart in the first exhibitions of computer art. He used that bulletin to say the medium should not exist as art.\n\nWhat he wrote\n\nNake begins with his own position: \"I was involved in this development from its beginning onward (1964). I found the way the art scene reacted to the new creations interesting, pleasing and stupid. I stated in 1970 that I was no longer going to take part in exhibitions.\"\n\nHe grants that the computer had produced \"interesting new methods\", and that the results had not changed art's repertoire. Then he turns to the market:\n\n\"The dominating and most important person in the art world today is the art dealer. He determines what is to be sold and what is not. It is the art dealer who actually created a new style, not the artist.\"\n\nProgress in the world of pictures, he writes, is the same as in the world of \"fashinable [sic] clothes and cars\", with a new fashion presented each autumn, \"Paris, London for clothes, Detroit for cars, New York for pictures\". And computer art is \"nothing but one of the latest of these fashions, emerging from some accident, blossoming for a while, subject matter for shallow 'philosophical' reasoning based on prejudice and misunderstanding as well as euphoric over-estimation, vanishing into nowhere giving room to the next fashion.\"\n\nHis conclusions are short. \"Computers ought not to be used for the creation of another art fashion.\" \"There is no need for the production of more works of art, particularly no need for 'computer art'.\" And: \"I don't see a task for the computer as a source of pictures for the galleries.\"\n\nThe dealer decides\n\nNake made no claim that computer art was bad. His concern was what would happen to it: it would be shaped by the people who sell it, presented as a new fashion and judged by its novelty.\n\nFifty years later the auction houses wrote much of its history. In 2022 Sotheby's sold early plotter drawings in a sale called Natively Digital 1.3: Generative Art, among them a Vera Molnár from 1976, and the auction house has published an article calling her \"The Grande Dame of Generative Art\". In 2025 Christie's held what it presented as its first sale devoted entirely to AI art, and put a drawing from 1966 by Charles Csuri and a drawing by Harold Cohen's AARON under the same heading as new work, as described in The rule is the work. That is close to what Nake described in 1971: a new style, defined by those who sell it.\n\nThis applies to JAEV\n\nJAEV is a gallery. It shows and sells work, including work made by programs, and it writes texts like this one, which help to define what that work is and where it comes from. Nake's objection is aimed at exactly that position. We do not think it can be answered by saying that our intentions are different; his point was that the structure decides, not the intentions of the people in it. The most we can do is to say so.\n\nNot a refusal of the machine\n\nIt would be easy to read the text as a rejection of computers, but it argues the opposite. \"Questions like 'is a computer creative' or 'is a computer an artist' or the like should not be considered serious questions, period,\" Nake writes. \"Computers can and should be used in art in order to draw attention to new circumstances and connections and to forget 'art'.\"\n\n\"We should not be interested in producing some more nice and beautiful objects by computers. We should be interested in producing a film on, say, the distribution of wealth.\"\n\nAesthetic information on its own, he writes, \"is interesting only for the rich and the ruling\". The role of the computer \"in the production of aesthetic information per se and for the making of profit is dangerous and senseless.\"\n\nWhat happened next\n\nNake became a professor of graphic data processing at the University of Bremen in 1972. The DAM Digital Art Museum describes the decision as one not to produce any more computer art, \"which he considered would end up catering to the art market\". According to his biography at Media Art Histories, he took part in a large number of exhibitions between 1966 and 1972. In November 2004 he had a retrospective at the Kunsthalle Bremen and the ZKM in Karlsruhe, showing the early graphic works alongside new interactive installations.\n\nThe same DAM page says that he \"continues to exhibit his work regularly as an artist represented by DAM Gallery (Berlin)\". In 2025 he received the ACM SIGGRAPH Distinguished Artist Award for Lifetime Achievement in Digital Art. The objection to the dealer now sits on a dealer's website, written into the artist's biography.\n\nIt is the point, and not a case of hypocrisy: a criticism of a structure has no exit for the individual inside it, not even for the person who wrote it.\n\nSince 1971 there have been thousands of generative series, sold, collected and catalogued. We are not aware of the film on the distribution of wealth.\n\nFurther reading\n\nFrieder Nake, \"There Should Be No Computer Art\", PAGE 18 (1971), at compart, University of Bremen.\n\nThe rule is the work. A prompt is a wish., on generative art and image generators.\n\nGeorg Nees, whose exhibition in Stuttgart in 1965 opened the field Nake describes.\n\nVera Molnár and Generative Art."},
{"type": "editorial", "title": "The rule is the work. A prompt is a wish.", "url": "https://jaev.gallery/editorial/the-rule-is-the-work/",
   "description": "Generative art has meant writing the system yourself. Why prompting someone else's image model is something else, and what AI is good for.",
   "datePublished": "2026-10-10", "dateModified": "2026-10-10",
   "author": "JAEV Editorial",
   "about": [{"name": "generative art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1502032"}, {"name": "AI art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q65066631"}], "mentions": [{"name": "Vera Molnár", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1658002"}, {"name": "Harold Cohen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92723"}, {"name": "Philip Galanter", "type": "Person", "sameAs": null}, {"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "Ted Chiang", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q503095"}, {"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "Christie's", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q503176"}],
   "sources": [{"title": "“Christie's All-A.I. Sale Surpasses Expectations”. Artnet News, March 2025", "url": "https://news.artnet.com/market/christies-augmented-intelligence-ai-auction-results-2615818"}, {"title": "“Thousands Call on Christie's to Nix AI Art Auction”. Hyperallergic, 11 February 2025", "url": "https://hyperallergic.com/thousands-call-on-christies-to-nix-ai-art-auction/"}, {"title": "“Cancel the Christie's AI Art Auction”. Open letter, openletter.earth", "url": "https://openletter.earth/cancel-the-christies-ai-art-auction-f5135435"}, {"title": "Charles Csuri, Bspline Men, 1966; Harold Cohen, Untitled (i23-3758), 1987; Refik Anadol, Machine Hallucinations – ISS Dreams – A, 2021. Lot pages, Christie's, Augmented Intelligence, 2025", "url": "https://onlineonly.christies.com/s/augmented-intelligence/overview/3837"}, {"title": "Vera Molnár, 1% de désordre (1% of disorder), 1976. Sotheby's, Natively Digital 1.3: Generative Art, 2022", "url": "https://www.sothebys.com/en/buy/auction/2022/natively-digital-1-3-generative-art/1-de-desordre-1-of-disorder"}, {"title": "Vera Molnár, Parcours 10x10 cinq rectangles, 1976. Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O1488631"}, {"title": "“Harold Cohen: AARON”, 3 February – 19 May 2024. Whitney Museum of American Art, New York", "url": "https://whitney.org/exhibitions/harold-cohen-aaron"}, {"title": "Harold Cohen, “What is an Image?”. Invited paper, proceedings of the 6th International Joint Conference on Artificial Intelligence, Tokyo, 1979", "url": "https://www.aaronshome.com/aaron/publications/whatisanimage.pdf"}, {"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal, Spring 2009", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}, {"title": "Sol LeWitt, “Paragraphs on Conceptual Art”. Artforum 5, no. 10, June 1967", "url": "https://monoskop.org/images/3/3d/LeWitt_Sol_1967_1999_Paragraphs_on_Conceptual_Art.pdf"}, {"title": "Philip Galanter, “What Is Generative Art? Complexity Theory as a Context for Art Theory”. Generative Art conference, Milan, 2003", "url": "https://www.mat.ucsb.edu/~g.legrady/academic/courses/21s255/r/galanter.pdf"}, {"title": "Ted Chiang, “Why A.I. Isn't Going to Make Art”. The New Yorker, 31 August 2024", "url": "https://www.newyorker.com/culture/the-weekend-essay/why-ai-isnt-going-to-make-art"}],
   "related": {"editorial":["generative-art","vera-molnar","harold-cohen","georg-nees","sol-lewitt"],"exhibitions":[],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/rule-sentence-walk-jaev.jpg", "alt": "A single thin black line on off-white paper, looping round and round to form a wide ring of interlocking angular loops around an empty circle in the middle.", "credit": "The title of this text, walked 72 times by the rule given at the end of it. One line, 2,952 steps. Made by JAEV, CC BY 4.0."},
   "text": "Between 20 February and 5 March 2025, Christie's in New York held Augmented Intelligence, which the auction house presented as its first sale devoted entirely to art made with artificial intelligence. Twenty-eight of thirty-four lots sold, for a total of $728,784. Before it opened, an open letter asked Christie's to cancel it. The letter, which had more than 4,000 signatures within days of its publication on 8 February and 6,566 (5,720 of them verified) by October 2026, alleged that many of the works were made with models \"known to be trained on copyrighted work without a license\"; artists in the sale disputed that description.\n\nThe catalogue put three very different things under one heading. There was Bspline Men, a drawing in ink made in 1966 by Charles Csuri with an IBM mainframe and a drum plotter, which sold for $50,400. There was Untitled (i23-3758), a drawing from 1987 by Harold Cohen's program AARON, which sold for $11,340, just above its low estimate. And there were recent works, among them the top lot, Refik Anadol's Machine Hallucinations – ISS Dreams – A (2021), which sold for $277,200 and was made, according to Christie's catalogue, with a model trained on more than a million images from the International Space Station and satellites. All three were sold as \"AI art\". None of the three was made by typing a request into somebody else's image generator. What ties them together is an older idea: that the artist writes the system that makes the work.\n\nThe console of an IBM 7094, the type of mainframe Christie's catalogue gives for Bspline Men. Computer History Museum, Mountain View. Photo: Marcin Wichary, 2008, CC BY 2.0, via Wikimedia Commons.\n\nA rule with one per cent of disorder\n\nIn 1976 Vera Molnár made a plotter drawing called 1% de désordre (1% of disorder): ink on Benson paper, 36 × 55 cm. The Victoria and Albert Museum describes the program she used, Molnart, written with her husband François Molnár, and the principle it calls \"1% disorder\": slight deviations from a strict pattern.\n\nIn JAEV's reading, the plotter's part was the simplest: it drew what the program told it to draw. What made the drawing a work came before that: the choice of forms, the size of the field, and above all the decision that the order should fail, and by how much. The rule was Molnár's. So was the exception.\n\nA Calcomp 565 drum plotter from around 1966, a type of machine that drew computer output with a pen on a roll of paper. Not necessarily the plotter Molnár used. Photo: Ryan Somma, CC BY-SA 2.0, via Wikimedia Commons.\n\nA program as a self-portrait of a method\n\nHarold Cohen was an established painter in London when he conceived the software in the late 1960s at the University of California, San Diego; he named it AARON in the early 1970s. The Whitney Museum, which showed the program's history in 2024, says that he \"devoted his life to exploring the potential of artificial intelligence to translate an artist's knowledge and process into code\", and that he built his own plotters and painting machines to carry out what it produced. The Whitney calls AARON \"the earliest artificial intelligence (AI) program for artmaking\". It is more exact to call it Cohen's account of how he himself drew, written as rules, which he went on revising until his death in 2016.\n\nThree of the cognitive skills Cohen says he chose \"at the outset\" for AARON, in \"What is an Image?\" (1979): the ability to differentiate between figure and ground, between open and closed forms, and between insideness and outsideness. Diagram by JAEV; not a work by Harold Cohen or AARON. CC BY 4.0. More in Harold Cohen and AARON.\n\nIn February 1965 the philosopher Max Bense published a three-page text, \"Projekte generativer Ästhetik\" (Projects of generative aesthetics), in issue 19 of the series rot, which was sold at the opening of Georg Nees's exhibition in Stuttgart on 5 February, an event billed as \"Generative Computergrafik\". Frieder Nake has written that the text, \"in retrospect, must be considered the first manifesto of computer art\", though he adds that \"the style is not manifesto-like at all\". Sol LeWitt, writing about conceptual art in Artforum in 1967, described it this way: \"The idea becomes a machine that makes the art.\" In each case someone wrote the machine.\n\nWhat the definition says\n\nA widely quoted definition of generative art is Philip Galanter's, from 2003: \"any art practice where the artist uses a system, such as a set of natural language rules, a computer program, a machine, or other procedural invention, which is set into motion with some degree of autonomy contributing to or resulting in a completed work of art.\"\n\nRead literally, that includes typing a prompt into a commercial image generator: the generator is a system, it runs with a great deal of autonomy, and the result is an image. Galanter's definition does not say who has to have made the system.\n\nThis is JAEV's reading, not Galanter's: the definition needs that criterion to be useful. Molnár, Cohen and LeWitt each made the system that then made the work. They took responsibility for its decisions, even the ones they left to chance. An artist who trains a model on material of their own choosing, as several in the Christie's sale did, is doing the same thing with a different tool. Someone who writes a sentence for a model a company built, from images they did not choose and mostly cannot see, has used a system without writing one.\n\nWhat a prompt is\n\nThe American writer Ted Chiang made a related argument in The New Yorker in 2024. \"Art is something that results from making a lot of choices,\" he wrote. A prompt, in his account, makes very few. Of an image made from a prompt in a program like DALL-E, he wrote: \"Most of the choices in the resulting image have to be borrowed from similar paintings found online; the image might be exquisitely rendered, but the person entering the prompt can't claim credit for that.\"\n\nThat is Chiang's description. It is not a technical account of how such models work, but the consequence he points to can be seen. In JAEV's observation, images made this way tend to arrive at the same few qualities – the same polished skin, the same cinematic light, the same evenly distributed detail – which belong to the system, not to the person who asked for them. A prompt is a wish. It states what one would like to see and leaves undecided how anything is made.\n\nWhat AI is for\n\nNone of this makes AI useless to artists, since much of an artist's working life is spent on things other than making art: applications, budgets, press releases, CVs, translations, deadlines and correspondence. That is where these tools are good. It is also where a few saved hours go straight back to the work.\n\nThe rule at the top of this page\n\nThe image at the top of this page was made by a rule, written for this text:\n\nWalk through the sentence \"The rule is the work. A prompt is a wish.\" one character at a time, taking one step of equal length for each. After a vowel, turn 60 degrees to the right; after any other letter, turn 25 degrees to the left; after a space or a full stop, go straight on. Repeat the sentence until the line is back where it began.\n\nOne pass through the sentence turns the line by 185 degrees in all, so it takes 72 passes, 2,952 steps, before the line returns exactly to its starting point, facing the same way. Anyone can draw it again from the rule, by hand or by program, and get the same figure; only where it starts and which way it first faces are left free, and they turn the figure without changing it. The program that drew the images here is published with this text.\n\nThe first of the 72 passes, starting at the square: one step per character, red where the line turns right after a vowel. Made by JAEV, CC BY 4.0.\n\nMolnár's one per cent was a decision about where her own rule should break. Writing a prompt involves no rule that could break by one per cent.\n\nFurther reading\n\nGenerative Art, JAEV's introduction to the field.\n\nVera Molnár and Sol LeWitt: the rule and the instruction.\n\nHarold Cohen and AARON: a painter's rules for drawing, written as a program.\n\nWhitney Museum of American Art: Harold Cohen: AARON (2024).\n\nPhilip Galanter, \"What Is Generative Art?\" (2003).\n\nTed Chiang, \"Why A.I. Isn't Going to Make Art\", The New Yorker (2024)."},
{"type": "editorial", "title": "Harold Cohen", "url": "https://jaev.gallery/editorial/harold-cohen/",
   "description": "Harold Cohen's AARON drew for forty years and learned to colour without seeing. His own published rules, and reconstructions of how the program worked.",
   "datePublished": "2026-10-09", "dateModified": "2026-10-09",
   "author": "JAEV Editorial",
   "about": [{"name": "Harold Cohen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92723"}], "mentions": [{"name": "AARON", "type": "Thing", "sameAs": null}, {"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}, {"name": "Victoria and Albert Museum", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q213322"}, {"name": "Whitney Museum of American Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q639791"}, {"name": "Stanford Artificial Intelligence Laboratory", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q22704990"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}],
   "sources": [{"title": "Harold Cohen, 20:28, 1985 (E.964-2008). Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O239975/"}, {"title": "“Harold Cohen: AARON”, 3 February – 19 May 2024. Whitney Museum of American Art, New York", "url": "https://whitney.org/exhibitions/harold-cohen-aaron"}, {"title": "Cristina Della Coletta, “Harold Cohen”, In Memoriam. University of California Academic Senate", "url": "https://senate.universityofcalifornia.edu/_files/inmemoriam/html/HaroldCohen.html"}, {"title": "Harold Cohen, “How to Draw Three People in a Botanical Garden”. Invited paper, AAAI conference, 1988", "url": "https://www.aaronshome.com/aaron/publications/how2draw3people.pdf"}, {"title": "Harold Cohen, Amsterdam Suite A, 1977 (E.328-2009). Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O499578/"}, {"title": "Harold Cohen, “What is an Image?”. Invited paper, 6th International Joint Conference on Artificial Intelligence, Tokyo, 1979", "url": "https://www.aaronshome.com/aaron/publications/whatisanimage.pdf"}, {"title": "Harold Cohen, “Colouring without Seeing: a Problem in Machine Creativity”. Undated; written after 1998", "url": "https://www.aaronshome.com/aaron/publications/colouringwithoutseeing.pdf"}, {"title": "Harold Cohen, “The Further Exploits of AARON, Painter”. Text for Stanford Humanities Review, October 1994", "url": "https://www.aaronshome.com/aaron/publications/furtherexploits.pdf"}, {"title": "“The Robotic Artist: AARON in Living Color”. Exhibition booklet with a conversation between Harold Cohen and Becky Cohen, The Computer Museum, Boston, 1 April – 29 May 1995", "url": "https://tcm.computerhistory.org/CHMfiles/Harold%20Cohen,%20%20Robotic%20Artist,%201995.pdf"}, {"title": "Harold Cohen, 0305-08, 2002 (E.264-2005). Victoria and Albert Museum, London", "url": "https://collections.vam.ac.uk/item/O114804/"}, {"title": "Harold Cohen, “Fingerpainting for the 21st Century”, 8 February 2016", "url": "https://www.aaronshome.com/aaron/publications/8Feb2016Fingerpainting-for-the-21st-Century-with-Figures.pdf"}],
   "related": {"editorial":["casey-reas","georg-nees","sol-lewitt","generative-art"],"exhibitions":[],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/cohen-colour-by-lightness-diagram-jaev.jpg", "alt": "Four panels. Top left: a landscape of rocks and leaves in many different colours. Top right: the same landscape with the same colours made lighter and darker. Bottom left: the top left image in grey, a single flat grey with nothing visible. Bottom right: the top right image in grey, with every form still clearly visible.", "credit": "Left: every form a different hue, all at the same lightness. Right: the same hues, with neighbouring forms differing in lightness. Below: both reduced to lightness alone. Diagram by JAEV after Cohen's account; the forms only loosely follow AARON's rocks and plants. CC BY 4.0."},
   "text": "On 16 August 1985, at 20:28, a plotter finished a drawing of three figures and three balls: a seated man and two women who seem to be dancing. Below them it wrote \"Aaron 8-16-85 20:28\". The Victoria and Albert Museum, which owns the sheet, notes that the signature was made by the program itself, unlike other AARON drawings, which Harold Cohen signed.\n\nAARON was the program Cohen wrote, rewrote and extended from the early 1970s until his death in 2016. Three years after that drawing he wrote that he regarded style as \"the signature of a complex system\". The question his work keeps returning to is what such a system has to know before it can make a picture, and what it can do without. Its answer, reached slowly and against his own expectations, was that it could do without seeing.\n\nA painter in a laboratory\n\nCohen was born in 1928 and studied painting at the Slade School of Fine Art in London. In 1966 he represented Britain at the Venice Biennale. He went to the University of California, San Diego in 1968 as a visiting lecturer, and from there spent two years at the Artificial Intelligence Laboratory at Stanford, where Edward Feigenbaum had invited him and where AARON took shape. He stayed at San Diego until he retired in 1994.\n\nUnlike most of the artists in this series, who used the computer to vary a geometric rule, Cohen wanted a program that would make drawings in the way he thought people make them, and he began from very little. In 1979 he wrote that he had chosen, \"at the outset\", three abilities: to differentiate between figure and ground, between open and closed forms, and between insideness and outsideness.\n\nThe rules\n\nThe program was built as a set of rules of the form if this, then that. Cohen did not publish AARON's code, which by the 1990s ran to more than a megabyte of Lisp. But in 1979 he printed some of its rules in his own notation, and nothing closer to AARON's source can be read today:\n\nIf (this is a first development\nand the last figure was open\nand at least n figures have been done\nand at least q of them were open\nand at least t units of space are now available)\nThen\nThis figure will be closed\n\nAbove all the rules sat what Cohen called an avoidance protocol, which prohibited the program \"from ignoring the existence of one figure in drawing another one\". Each decision depended on what was already on the paper, and AARON did not decide in advance what the picture would show.\n\nThe three differentiations Cohen chose for AARON: figure and ground, open and closed forms, inside and outside. The zigzag follows the rule he describes, to move a given distance and then change direction. Diagram by JAEV; not a work by Harold Cohen or AARON. CC BY 4.0.\n\nSteering, not plotting\n\nBy the end of the 1970s AARON drew on the floor with a small turtle: two wheels, each driven by its own stepping motor. Cohen did not let the program send it to coordinates. He found it \"entirely unreasonable\" to have built a device that could be driven like a car and then use it to simulate a plotter. Instead the program steered. For each command it looked at the angle to the next signpost and at how far it still had to go, set the speeds of the two wheels, and drove a short arc, moving more carefully near the end. A sonar system then reported where the turtle actually was. In Cohen's words, the program did not say \"go to x,y\" but \"do the following and then say where you are\".\n\nSteering towards signposts, one arc per command. Left: without error. Right: each command is executed with some error; asking where the turtle is after each one brings it to its destination (black), while the same commands without asking miss it (grey). Diagram by JAEV after Cohen's description of 1979; not his program. CC BY 4.0.\n\nCohen added that the generating algorithm \"simplified enormously\" and that the freehand quality of the line \"improved noticeably\". A drawing that steers looks drawn. The same thinking shaped the program's later figures: in the 1980s AARON built each body from an inner \"core figure\" of articulation points, then traced an enclosing line around it. Cohen insisted that neither then nor later did AARON have \"any knowledge pertaining to the surfaces of things\".\n\nFrom the inside out: points for the joints, a body around them, and only the outline drawn. Diagram by JAEV after Cohen's account of AARON's core figures (1994); not his program or data. CC BY 4.0.\n\nColour without seeing\n\nFor most of its life AARON drew and Cohen coloured. He \"had always colored some number of AARON's drawings\", and many became paintings and murals. By 1986 it seemed to him \"inappropriate that a program smart enough to generate an endless stream of original drawings was incapable of doing its own coloring\".\n\nThe difficulty was not knowing what a painter knows. It was that a painter sees. \"Human beings can see the results of putting two colors next to each other, and can proceed on the basis of this feedback,\" Cohen said in 1995; the program \"can't see in the same sense that you or I can see\", so he had to come up with rules \"that would serve in place of the visual feedback that humans use\". He found the key in something he had told painting students for years: \"the most important single thing about color is not spectral hue; it's how light or dark it is.\"\n\nHe went further in a later paper. Increasing the difference in hue between two colours \"only increases legibility if there is adequate separation in brightness\"; at near-equal brightness, the eye has more difficulty finding the edge as the hue difference grows, not less. For the painting machine he mixed 1,200 samples of dyes, kept about 800, and arranged them by eye around a circle of 180 positions. From these AARON built what he called colour chords. First it spaced the colours evenly around the circle, then by an additive series. Then it sorted the chord by brightness and diluted each colour to an equal step. Since water can make a dye lighter but never darker, a colour that was already too light could not be corrected; so in the last step the program searched the less pure samples at that position, and then the neighbouring positions, until it found one dark enough. The result, Cohen wrote, \"was a guaranteed minimum perceptual separation between any two components of the chord\".\n\nThe four steps of AARON's colour chords, after Cohen's description: equal spacing; additive spacing; sorted and diluted to equal steps of lightness, where one colour is too light and is marked; and a darker neighbour found for it. The samples are invented, not Cohen's dyes. Reconstruction by JAEV; not his program or data. CC BY 4.0.\n\nThe first paintings made this way, at the Computer Museum in Boston in 1995, were \"quite varied in quality\", Cohen admitted, until he solved the dilution problem. The program also held knowledge that had nothing to do with colour. \"It would never decide to paint a face green,\" he said, \"because it doesn't believe that faces can be green.\"\n\nIn the 2000s AARON left the figures and returned to abstraction. For the large prints it made from 2002, Cohen insisted that labels and image credits should read \"Digital print by AARON, a computer program written by Harold Cohen\".\n\nBack to the hand\n\nIn the last years the division of labour turned around once more. AARON made drawings on one computer; Cohen coloured them with his fingers on a touch screen that he described as seven-foot. In February 2016, a little over two months before he died, he wrote that he had changed the terms of his relationship with \"my collaborator\": \"Now I am working almost entirely in the program's space.\"\n\nIn JAEV's reading this makes Cohen the opposite case to Casey Reas, who writes his systems in English first so that they can be made again when the machines change. Apart from the few rules Cohen chose to print, almost nothing of AARON's rules was written down outside the program. The rules of Sol LeWitt, Vera Molnár and Georg Nees could be stated in a sentence or two. Cohen's aim was harder to state: not a rule for a picture, but what an artist knows, including how to colour without seeing. The signature under the drawing from 1985 was written by the program, but by his own definition the style was the signature of the whole system, and he built that system for more than forty years.\n\nFurther reading\n\nHarold Cohen's own papers at aaronshome.com, among them What is an Image? (1979), How to Draw Three People in a Botanical Garden (1988) and Colouring without Seeing.\n\nPamela McCorduck, Aaron's Code: Meta-Art, Artificial Intelligence, and the Work of Harold Cohen (1991), on the Internet Archive.\n\nWhitney Museum of American Art: Harold Cohen: AARON (2024).\n\nVictoria and Albert Museum: works by Harold Cohen in the collection.\n\nJAEV Editorial: Generative Art, Casey Reas, Georg Nees."},
{"type": "editorial", "title": "Ture Sjölander", "url": "https://jaev.gallery/editorial/ture-sjolander/",
   "description": "Monument, 1967: Ture Sjölander and Lars Weck bent the Beatles, Chaplin and the Mona Lisa with tones from waveform generators as they became a television signal.",
   "datePublished": "2026-10-08", "dateModified": "2026-10-08",
   "author": "JAEV Editorial",
   "about": [{"name": "Ture Sjölander", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q7854827"}], "mentions": [{"name": "Gene Youngblood", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q747459"}, {"name": "Nam June Paik", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q158056"}, {"name": "Moderna Museet", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1274511"}, {"name": "Sveriges Radio", "type": "Organization", "sameAs": null}, {"name": "video art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q682010"}],
   "sources": [{"title": "Gene Youngblood, Expanded Cinema. New York: E. P. Dutton, 1970, pp. 331–334 (“Ture Sjölander, Lars Weck, Sven Höglund: Video Monument in Sweden”)", "url": "https://www.ubu.com/historical/youngblood/expanded_cinema.pdf"}, {"title": "“MONUMENT 1967 by the artist Ture Sjolander and Lars Weck …”. YouTube, channel @tubeture (Ture Sjolander), uploaded 18 March 2009, 9:53", "url": "https://www.youtube.com/watch?v=Xt5VjKHAow8"}, {"title": "“Ture Sjolander and Bror Wilkstrom Raster Scan Device”. Video History Project", "url": "https://www.videohistoryproject.org/ture-sjolander-and-bror-wilkstrom-raster-scan-device"}, {"title": "Ture Sjölander and Lars Weck, Monument, 1967 (MOM/2011/100). Moderna Museet, Stockholm", "url": "https://sis.modernamuseet.se/en/objects/83250/monument"}, {"title": "Ture Sjölander, Gustav VI Adolf, 1967 (NMG 272/1967). Moderna Museet, Stockholm", "url": "https://sis.modernamuseet.se/en/objects/30940/gustav-vi-adolf"}, {"title": "Ture Sjölander, works in the collection. Moderna Museet, Stockholm", "url": "https://sis.modernamuseet.se/en/people/549/ture-sjolander/objects"}, {"title": "“Ture Sjolander”. Video History Project", "url": "https://www.videohistoryproject.org/ture-sjolander"}, {"title": "Ture Sjölander, Automatic Light Painting on Canvas with a Coin, 1966 (MOMB 110). Moderna Museet, Stockholm", "url": "https://sis.modernamuseet.se/en/objects/245"}],
   "related": {"editorial":["computer-art-in-sweden","georg-nees","generative-art"],"exhibitions":[],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/sjolander-weck-monument-1967-mm-2011-109.jpg", "alt": "A silkscreen print in pale blue on a bright orange ground: a photographic image of a person, broken into wavy outlines and patches, so that a face and shoulders can only just be made out.", "credit": "Ture Sjölander and Lars Weck, Monument, 1967. Silkscreen on paper, one of two sheets, 68 × 61 cm each. Moderna Museet, Stockholm, donation 2011 from Sven Boman. Work © Ture Sjölander and Lars Weck. Photo: Prallan Allsten/Moderna Museet."},
   "text": "In January 1968 Swedish television broadcast a programme in which some of the best-known faces in the world came apart. The Beatles, Charlie Chaplin, Picasso, the Mona Lisa and the King of Sweden appeared on screen and then began to ripple, stretch and dissolve. The American critic Gene Youngblood, who described the programme two years later, wrote that the transformations were \"at first subtle, like respiration, then increasingly violent until little remains of the original icon\", and that each image finally \"disintegrates into a constellation of shimmering video phosphors\". He called the result \"an oddly beautiful collection of image sequences unlike any other video art\".\n\nThe programme was called Monument, and it was made by the artists Ture Sjölander and Lars Weck with Bengt Modin, a video engineer at Sveriges Radio, the Swedish Broadcasting Corporation. Its pictures were not distorted afterwards. They were bent at the moment they became a television signal.\n\nBending the signal\n\nMonument was made in the autumn of 1967 from film clips and slides of famous people and paintings, the \"monuments\" of world culture, and it was made in black and white. To broadcast a film, Swedish television used a flying-spot telecine: the film was projected towards a photocell, with a scanned raster as the source of light, and the point of light, in Youngblood's words, \"scans the screen fifty times per second\". Sjölander, Weck and Modin fed tones from waveform generators into the circuit that steered the point of light, changing the frequency and amplitude of its sweep. The result was recorded, filmed off a screen and edited by Sjölander and Weck into its final form.\n\nYoungblood compared the method to those used by Nam June Paik and others, with one difference: the Swedish group intervened at an earlier stage, while the image was still being turned into signal.\n\nTure Sjölander and Lars Weck, Monument, 1967: a 9 min 53 s video uploaded by Ture Sjölander to YouTube in 2009. Whether it is the whole programme as broadcast is not stated. UbuWeb has a version described as extracts, on its page for the film.\n\nTIME, 1966\n\nMonument was not Sjölander's first experiment of this kind. With Bror Wikström he had made TIME, a programme commissioned by Swedish television. The sources date it variously to 1965–66 and 1966, with broadcasts until 1969. In Sjölander's own account, a video synthesizer was temporarily built for it in spite of the technicians' doubts, and the same technical set-up was used for Monument a year later.\n\nWhether TIME or Monument came first is less clear than it may seem. Sjölander's pages quote a statement by Björn Hallström from 1976, which itself dates TIME to 1965–66, that the programme \"seems to be the first distortion of video-scan-line rasters achieved by applying tones from wave form generators\". The same pages include a letter from Rutt Electrophysics of 12 March 1974 that says the same of Monument, hedged (\"From literature available I gather\") and in a letter written to ask Sjölander for documentation. Both are documents published by Sjölander himself, and we have not found an independent source that settles it. Youngblood's account of Monument, written in 1970, is the earliest independent description of the technique we know of.\n\nTure Sjölander and Lars Weck, Monument, 1967. Silkscreen on paper, 63.5 × 49 cm, signed \"Ture Sjölander Lars Weck 67\". Moderna Museet, Stockholm, donation 2011 from Sven Boman. Work © Ture Sjölander and Lars Weck. Photo: Prallan Allsten/Moderna Museet.\n\nAn image generator\n\nWhat happened to Monument after the broadcast is perhaps its most modern feature. According to Youngblood, the programme was later seen across Europe, Asia and the United States, and it became \"an image-generator\": newspapers, magazines, posters, record albums and even textile factories used its pictures. The painter Sven Höglund, who entered the project after the film was finished, made oil paintings from them. He called them another phase of the same \"experiment in communication\". For him the common denominator was the mass-media picture, above all the television picture.\n\nThe silkscreen prints show how this worked. Moderna Museet holds a series of them from 1967, numbered in the form \"51/100/300\". On the television screen Monument was black and white. On paper it came out in colour, as in the sheets shown here: pale blue on orange, magenta on turquoise. The work about mass-media images circulated as a mass-media image, and changed colour on the way.\n\nTure Sjölander and Lars Weck, Monument, 1967. Silkscreen on paper, 55 × 69.5 cm. Not every sheet in the series shows a face; this one shows a regular pattern bent in the signal. Moderna Museet, Stockholm, donation 2011 from Sven Boman. Work © Ture Sjölander and Lars Weck. Photo: Prallan Allsten/Moderna Museet.\n\nThe museum also holds a print by Sjölander alone, Gustav VI Adolf (1967), numbered \"140/300\". The county council of Västernorrland gave it to the national collection in the year it was made. The king is one of the faces in Monument, yet the museum does not connect the print to the series.\n\nTure Sjölander, Gustav VI Adolf, 1967. Print; the museum records no technique. 65.2 × 50 cm according to a written source, signed \"140/300 Ture Sjölander -67\". Moderna Museet, Stockholm, donation 1967 from Västernorrland County Council. The museum does not list it as part of Monument. Work © Ture Sjölander. Photo: Åsa Lundén/Moderna Museet.\n\nAfter Monument\n\nSjölander was born in 1937. In his own account, he received the Royal Swedish Academy of Fine Arts' project grant in 1975 for his electronic works, and from 1979 to 1986 he led Video-Nu in Stockholm, an artists' laboratory for new electronic technology. Moderna Museet records him as living in Australia. Lars Weck lived from 1938 to 2015. Moderna Museet holds 24 works by Sjölander, most of them prints from Monument, and one installation, Automatic Light Painting on Canvas with a Coin (1966).\n\nMonument was made with analog television equipment, tones and an engineer who let artists into the circuit. It belongs with the other Swedish experiments of the period, told in Computer Art in Sweden, in which artists made new images on technology that belonged to someone else, in this case the national broadcaster.\n\nIn JAEV's reading, Monument deserves to be better known, as one of the early works in which artists worked directly on the television signal. It is visually striking, it was seen far beyond Sweden, and it understood something early: that a picture of a famous face is never only a picture, but something that travels, is copied and changes on the way. Sjölander and Weck made that journey the work.\n\nAbout the images: we have not been in contact with Ture Sjölander or the heirs of Lars Weck. The prints are shown with credit to the artists and to Moderna Museet, which holds them. If the artist, Lars Weck's heirs or the museum would rather they were not shown, we will remove them.\n\nFurther reading\n\nGene Youngblood, Expanded Cinema (1970), pages 331–334, on Monument. The same passage appears on UbuWeb's page for the film, next to a video described as extracts.\n\nModerna Museet, Stockholm: works by Ture Sjölander in its collection.\n\nVideo History Project: Ture Sjölander, with documentation of his own.\n\nJAEV Editorial: Computer Art in Sweden and Georg Nees."},
{"type": "editorial", "title": "Georg Nees", "url": "https://jaev.gallery/editorial/georg-nees/",
   "description": "In 1965 Georg Nees showed computer drawings in Stuttgart. Asked if his machine could draw like an artist, he said yes, if the artist could describe how.",
   "datePublished": "2026-10-08", "dateModified": "2026-10-08",
   "author": "JAEV Editorial",
   "about": [{"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}], "mentions": [{"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "Frieder Nake", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q92703"}, {"name": "Konrad Zuse", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q60093"}, {"name": "Siemens", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q81230"}, {"name": "University of Stuttgart", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q122453"}, {"name": "Victoria and Albert Museum", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q213322"}, {"name": "ALGOL 60", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1209759"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}],
   "sources": [{"title": "Frieder Nake, “The Semiotic Engine: Notes on the History of Algorithmic Images in Europe”. Art Journal, Spring 2009", "url": "https://monoskop.org/images/1/10/Nake_Frieder_2009_The_Semiotic_Engine_Notes_on_the_History_of_Algorithmic_Images_in_Europe.pdf"}, {"title": "Georg Nees, Schotter, 1968–1970. Lithograph on paper. Victoria and Albert Museum, London, E.217-2008", "url": "https://collections.vam.ac.uk/item/O221321/"}, {"title": "Zellyn Hunter, “Schotter – Georg Nees – Part 1”, 2024", "url": "https://zellyn.com/2024/06/schotter-1/"}, {"title": "Georg Nees, Generative Computergraphik. Doctoral dissertation, 1969, with the 2006 reprint. Internet Archive", "url": "https://archive.org/details/generative_computergraphik"}, {"title": "Georg Nees, Sculpture 1 (Plastik 1), 1965–1968. Screenprint. Victoria and Albert Museum, London, E.61-2008", "url": "https://collections.vam.ac.uk/item/O154975/"}],
   "related": {"editorial":["generative-art","manfred-mohr","sol-lewitt","computer-art-in-sweden"],"exhibitions":["difficulty"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/nees-order-disorder-reconstruction-jaev.jpg", "alt": "A tall sheet with a grid of small outlined squares, twelve across and twenty-two down. The top rows are straight and orderly; further down the squares shift and tilt more and more, and the bottom rows are scattered and overlapping.", "credit": "Reconstruction by JAEV after the method of Nees's Schotter: 12 × 22 squares whose displacement and rotation grow with each square drawn. The random numbers, line and paper are JAEV's; not an original work by Georg Nees. CC BY 4.0."},
   "text": "On the afternoon of 5 February 1965, a small exhibition opened in the seminar room of the Institute of Philosophy in Stuttgart, on the eighth floor of the Hahn-Hochhaus; it is usually listed as having been shown at the Studiengalerie of the Technische Hochschule. The institute's director, the philosopher Max Bense, often showed concrete art and poetry there. This time the works were thin black lines, matrices of small figures and overlapping rectangles, and the announcement said they were computer-generated. Their author, a mathematician from Siemens in Erlangen called Georg Nees, explained how his computer had drawn them.\n\nFrieder Nake, who was in the room and set down what he remembered of it in 2009, recalls that many of the artists present were hostile. One of them stood up and asked whether Nees could make his machine draw the way an artist draws. Nees thought for a moment and answered: \"Yes, I can. If you can tell me precisely how to define your way of drawing.\" Professors from the Academy of Fine Art left, some slamming the doors. Bense tried to calm them: \"what you see here is only artificial art.\"\n\nJAEV's reading is that this answer holds the core of what came to be called generative art: a drawing can be made by a machine if the way it is made can be described exactly. The rest of Nees's work can be read as a test of that sentence.\n\nAn engineer and a Zuse Graphomat\n\nNees was born in Nuremberg in 1926, studied mathematics and physics at the universities of Erlangen-Nuremberg and Stuttgart, and worked as a software engineer at Siemens. There he had access to a Zuse Graphomat Z64, a flatbed drawing machine that the computer pioneer Konrad Zuse built in 1963. It drew from a paper tape holding data that a computer had calculated in advance.\n\nNees did not need to borrow a machine, as the artists in Computer Art in Sweden did; he worked where it was. That brought its own caution. In the autumn of 1964 he made his first three abstract drawings and sent them to the journal Grundlagenstudien aus Kybernetik und Geisteswissenschaft. He called them Statistische Graphik (probabilistic graphics), a title chosen, Nake writes, to protect his reputation as an engineer.\n\nThe program, not the hand\n\nNees wrote his programs in ALGOL 60, a language made for scientific computation. The booklet sold at the opening, issue 19 of Bense's series rot, contained six of his drawings, among them 23-Ecke (Polygon of 23 vertices) and Andreaskreuz (St Andrew's cross), both 1965, ink on paper, 29.7 × 21 cm. Their titles name the structure the program works with; within limits set in advance, the program decides the rest. The artist does not draw the lines. He decides how the lines are to be decided.\n\nThe same booklet contained a three-page text by Bense, \"Projekte generativer Ästhetik\" (Projects of generative aesthetics). Nake calls it, in retrospect, the first manifesto of computer art, and places what he calls the algorithmic principle at its heart. The word generative entered computer art in the same small square booklet as Nees's drawings, on the day of the opening.\n\nThe exhibition ran from 5 to 19 February 1965. In November the same year Nees and Nake showed together at Galerie Wendelin Niedlich in Stuttgart. Nake writes that the two of them are usually considered the first to exhibit algorithmic art in Europe. The exhibitions of that year are told in Generative Art.\n\nGeorg Nees in 1986. Photo: Alexander Kempkens, Wikimedia Commons, CC BY-SA 3.0.\n\nSchotter: order and disorder\n\nNees's best-known work, Schotter (Gravel), from 1968, makes the rule itself visible. Twelve squares sit side by side in a row, and twenty-two rows run down the sheet. At the top the squares stand straight and touch each other. With every square the program draws, it allows a little more random displacement and a little more random rotation, so that the grid loosens row by row until, at the bottom, the squares lie scattered like stones. The V&A describes Nees's interest as \"the relationship between order and disorder in picture composition\".\n\nA single counter, the number of squares drawn so far, sets how far each square may move and turn. That is what makes the drawing readable: you can see the instruction in the picture, and you can see chance growing under it. It is also an answer to the artist in Stuttgart. A way of drawing, here the gradual collapse of order, has been described precisely enough for a machine to carry out.\n\nThe image at the top of this page is not Schotter but JAEV's reconstruction of its method, made with our own random numbers. We are asking for permission to show Nees's own works, and will replace it when we have it.\n\nArtificial art\n\nNees took the question further than most. In 1969 he received his doctorate under Bense with a dissertation called Generative Computergraphik. He also made sculpture by computer. The V&A holds a screenprint, Sculpture 1 (Plastik 1), 1965–68, which it describes as made from the design for a sculpture that a computer-controlled milling machine cut from a block of wood, shown at the Venice Biennale in 1969; the record's materials field says aluminium. The Munich dealer Heike Werner, who specialises in early computer art, understands that the machine was tested on both materials and that there were two sculptures: no. 1 in aluminium and no. 2 in wood (email to JAEV, 27 October 2026).\n\nBense's phrase at the opening, \"artificial art\", was meant to calm the room, but it also names what Nees showed. The works were made by a program and a machine owned by a company. The question they raised was whether a way of drawing could be written down, and not whether a computer could be an artist.\n\nIn JAEV's reading, the same question was being asked at the same time without computers. Sol LeWitt wrote instructions from the late 1960s that other people carried out on the wall, which is the difference as much as the likeness: his rules were followed by hands, Nees's by a machine.\n\nFurther reading\n\nFrieder Nake, The Semiotic Engine: Notes on the History of Algorithmic Images in Europe (2009), an eyewitness account of the 1965 exhibitions.\n\nGeorg Nees, Generative Computergraphik, the 1969 dissertation and the 2006 reprint, on the Internet Archive (in German).\n\nZKM Center for Art and Media, Karlsruhe: Georg Nees.\n\nThe Victoria and Albert Museum, London: Schotter and other works by Nees.\n\nZellyn Hunter, Schotter – Georg Nees, a reading of the original program.\n\nGeorg Nees on Wikipedia.\n\nJAEV Editorial: Generative Art, Manfred Mohr, Sol LeWitt, Computer Art in Sweden."},
{"type": "editorial", "title": "Manfred Mohr", "url": "https://jaev.gallery/editorial/manfred-mohr/",
   "description": "Manfred Mohr drew his first computer art by hand, then at night on a weather service plotter in Paris. How the cube became his alphabet. By JAEV Editorial.",
   "datePublished": "2026-10-08", "dateModified": "2026-10-08",
   "author": "JAEV Editorial",
   "about": [{"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}], "mentions": [{"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "Paris 8 University", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q1194988"}, {"name": "Musée d'art moderne de Paris", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q857276"}, {"name": "Victoria and Albert Museum", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q213322"}, {"name": "CDC 6400", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q976542"}, {"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}],
   "sources": [{"title": "Manfred Mohr, “Manfred Mohr – 50 Year Celebration: Timeline”. emohr.com", "url": "https://www.emohr.com/ManfredMohr_50YearCelebration_TimeLine.html"}, {"title": "“SIGGRAPH 2013 Distinguished Artist Award: Mohr”. ACM SIGGRAPH History Archives", "url": "https://history.siggraph.org/award/siggraph-2013-distinguished-artist-award-mohr/"}, {"title": "Manfred Mohr, P-18 (random walk), 1969/1970. Plotter drawing on paper. Victoria and Albert Museum, London, E.115-2008", "url": "https://collections.vam.ac.uk/item/O199163/"}, {"title": "Manfred Mohr, P-21 (band structure), 1970. Photogravure on paper. Victoria and Albert Museum, London, E.105-2008", "url": "https://collections.vam.ac.uk/item/O199303/"}, {"title": "Manfred Mohr, “Computer Graphics – Une Esthétique Programmée, 1971”. emohr.com", "url": "https://www.emohr.com/paris-1971/index.html"}, {"title": "Manfred Mohr, “Cubic Limit, Generative Drawings, Part 1. Travaux de 1973–1975”, Galerie Weiller, Paris, 1975. emohr.com", "url": "https://www.emohr.com/paris-1975/index.html"}, {"title": "Manfred Mohr, “Cubic Limit II”, 1975–1977. emohr.com", "url": "https://www.emohr.com/paris-1977/index.html"}, {"title": "“Sol LeWitt: Cubic Forms”. Paula Cooper Gallery, New York", "url": "https://www.paulacoopergallery.com/exhibitions/sol-lewitt13"}, {"title": "Manfred Mohr, email to JAEV, 14 October 2026", "url": null}, {"title": "Prix Ars Electronica 1990, Computer Graphics, Golden Nica: Manfred Mohr, P-411-A. Jury statement. Ars Electronica archive", "url": "https://webarchive.ars.electronica.art/en/archives/prix_archive/prixJuryStatement.asp%3FiProjectID=2573.html"}],
   "related": {"editorial":["georg-nees","computer-art-in-sweden","sol-lewitt","generative-art","vera-molnar"],"exhibitions":["automatic-colour-cubes"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/manfred-mohr-p-021-g-1970.jpg", "alt": "A square sheet with eight horizontal lines of small black marks drawn by a plotter. Each line is a band of zigzags, steps, square waves and dense knots, read from left to right like lines of writing.", "credit": "Manfred Mohr, P-021-G, 1970. Plotter drawing on paper, 40 × 40 cm. Collection Spalter, USA. Image: Manfred Mohr, Wikimedia Commons, CC BY-SA 4.0."},
   "text": "In 1973 Manfred Mohr stopped looking for new forms and settled on one: the cube. \"The 12 edges of the cube became my alphabet to which I apply algorithms,\" he writes. It stayed at the centre of his work for more than forty years, together with its four-dimensional relative, the hypercube. This text is about what he does with those twelve lines, and how a jazz musician and painter came to them by way of borrowed computers.\n\nBefore the cube\n\nMohr was born in Pforzheim, Germany, in 1938, and began as a jazz musician and as a painter of gestural abstraction. The information aesthetics of the philosopher Max Bense changed his thinking; his painting moved towards geometry and rules. He wrote his first computer drawings in 1969, encouraged by the composer Pierre Barbaud, who made music with computers.\n\nHe wrote them at the new University of Paris in Vincennes, which had a computer but nothing to draw with. From the numbers his programs produced, he drew the lines by hand: \"Thus my hand was the plotter.\" Then, having seen the French weather service on television, he asked the Météorologie Nationale in Paris whether he could use its CDC 6400 computer and its large flatbed plotter. From 17 June 1970 he worked there at night and at weekends, until 1983.\n\nA CDC 6400, the computer model Mohr used at the Météorologie Nationale. This one stood at Kitt Peak National Observatory in Arizona. Photo: NOIRLab/AURA/NSF, Wikimedia Commons, CC BY 4.0.\n\nThe early programs were random walks and \"band structures\": lines that step, zigzag and turn into square waves, set in rows from left to right like writing, as in the drawing at the top of this page. The Victoria and Albert Museum in London holds early examples, P-18 (random walk) from 1969–70 and P-21 (band structure) from 1970. In 1971 the Musée d'Art Moderne de la Ville de Paris gave him a solo exhibition, Computer Graphics – Une Esthétique Programmée, with a plotter installed among the drawings.\n\nThe cube came later. In 1972 the search for a fixed structure was already under way, with the lines of squares and triangles used as alphabets; Mohr moved to the cube in 1973.\n\nTwelve lines\n\nA cube has eight corners and twelve edges. Drawn on paper it is a projection, and once it is rotated, the same twelve lines take on endlessly different angles. Mohr's method is to choose. He compares it to language and music: no one uses all 26 letters at once, or plays all twelve notes of an octave together; one chooses a few and makes a word or a melody. In the same way his programs pick subsets of the cube's edges and leave the rest out. \"I was never interested in showing the complete system but only aspects of it, thus visually fracturing the symmetry and at the same time creating an ambiguity in the sign.\"\n\nThe principle: a cube's twelve edges as an alphabet (left), and nine selections from it. Diagram by JAEV; not a work by Mohr, whose rules for choosing are his own. CC BY 4.0.\n\nIn the series Cubic Limit (1973–75) the cube rotates and the programs decide which lines appear. He also made two short computer-generated 16mm films, Cubic Limit and Complementary Cubes. The series was first shown at Galerie Weiller in Paris in 1975.\n\nIn Cubic Limit II (1975–77) he began to cut the cube. A square window, the front face of the unrotated cube, divides the lines into inside and outside; planes slice the cube into halves that rotate independently of each other, so that the tension shows along the cut. The geometry is simple. What it does to the eye is not: a familiar object breaks into signs that are hard to read as a cube at all.\n\nTwo cubes, 1974\n\nAt the same time in New York, Sol LeWitt made Variations of Incomplete Open Cubes (1974), which proposes all 122 variations in which a cube can be incomplete. Each variation is named by its place in the series; a steel version called Incomplete Open Cube 9/5 is the fifth variation of a cube with nine edges.\n\nIt is tempting to say that LeWitt showed the whole system and Mohr only parts of it, but that is not quite true. Mohr also worked through complete sets: by his own account he showed all combinations of a given number of the cube's lines in a series of thirteen drawings in 1975, and in his films. The difference lies elsewhere. LeWitt's cubes stand still and can be built: Incomplete Open Cube 9/5 is painted steel, an object in space with edges you can walk around. Mohr's cube turns, is projected, cut and clipped, and appears as lines on a flat surface. LeWitt asks how many ways a cube can be incomplete; Mohr asks what the parts of a cube look like when they are no longer held together by it.\n\nThe hypercube\n\nIn 1977 Mohr went from three dimensions to four. A four-dimensional hypercube has 16 corners and 32 edges and can only be seen as a projection. Mohr treats it as a graph, a network of points and lines, and uses it as his \"generator of signs\". From 1978 he draws \"diagonal paths\", routes along the edges from one corner to the opposite one; a hypercube has eight such pairs of corners, and 24 paths between each pair.\n\nThe hypercube work was new when Mohr showed in Lund. From 15 November to 13 December 1978 he had a solo exhibition, Dessins Génératifs, at Galerie S:t Petri, the gallery for experimental art that Jean Sellem ran in the city in the 1970s.\n\nA four-dimensional hypercube drawn in two dimensions: 16 corners and 32 edges (left), and one of the 24 shortest paths between two opposite corners, what Mohr calls a diagonal path (right). Diagram by JAEV; not a work by Mohr. CC BY 4.0.\n\nFrom 1987 he rotated the hypercube in four-dimensional space and projected the result onto the plane, so that the same lines change shape as the object turns through a dimension we cannot see. The structure stayed constant while the medium changed: plotter drawings, paintings, shaped canvases, and later works shown on screens with their own computers. P-306-O (1980–82) belongs to Divisibility I: the cube is cut into four parts, and each part is rotated independently before it is projected onto its quadrant. The result is painted in acrylic on four shaped canvases whose outer edges follow the lines of the drawing.\n\nManfred Mohr, P-306-O, 1980–82. Acrylic on canvas on wood, four parts, 250 × 250 cm. Collection Wolfson/Bourrows, USA. Image: Manfred Mohr, Wikimedia Commons, CC BY-SA 4.0.\n\nIn 1990 Mohr received the Golden Nica for computer graphics at the Prix Ars Electronica in Linz, for P-411-A; the jury noted that he does all the programming himself.\n\nAn instrument\n\nMohr explains the cube with an image from music. One recognises an instrument by its sound; he wanted a visual instrument, and found it in the cube and the hypercube. Every algorithm since then has used them as fixed structures, with fixed relationships between corners, edges and planes, and each work finds new relationships within them.\n\nThat is how one object could last more than forty years. The works are played on the cube, which he uses as an instrument and not as a subject: in black lines in 1973, cut and rotated in 1977, in four dimensions from 1987, in colour on canvas and screen in the 2010s.\n\nManfred Mohr, P1611_5220, 2012–13. Pigment ink on canvas, 122 × 122 cm. Owned by the artist. Image: Manfred Mohr, Wikimedia Commons, CC BY-SA 4.0.\n\nFurther reading\n\nManfred Mohr is represented by bitforms gallery, New York, and Galerie Charlot, Paris.\n\nManfred Mohr's own site, with a detailed timeline and pages on the 1971 exhibition, Cubic Limit and Cubic Limit II.\n\nThe Victoria and Albert Museum, London: P-18 (random walk) and P-21 (band structure).\n\nComputers and Automation, August 1970, with Mohr's Stairways in the same contest as the Swedish engineer Göran Sundqvist: scan of the issue.\n\nJAEV Editorial: Sol LeWitt, Computer Art in Sweden, Generative Art."},
{"type": "editorial", "title": "Computer Art in Sweden", "url": "https://jaev.gallery/editorial/computer-art-in-sweden/",
   "description": "Swedish computer art of the 1960s and 70s was made on borrowed machines: SAAB, a power company, IBM, Lund University. How that access shaped the work.",
   "datePublished": "2026-10-08", "dateModified": "2026-10-08",
   "author": "JAEV Editorial",
   "about": [{"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}], "mentions": [{"name": "Astrid Sampe", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q430667"}, {"name": "Göran Sundqvist", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19885695"}, {"name": "Jan W. Morthenson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1147400"}, {"name": "Lars-Gunnar Bodin", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5580344"}, {"name": "Knut Wiggen", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q6240816"}, {"name": "Sture Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5884840"}, {"name": "Charlotte Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4956816"}, {"name": "Mikael Jern", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63869789"}, {"name": "Holger Bäckström", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5591690"}, {"name": "Bo Ljungberg", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19352454"}, {"name": "Fylkingen", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q5511234"}, {"name": "Elektronmusikstudion", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q3672234"}, {"name": "IBM 1130", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q3146513"}],
   "sources": [{"title": "Sten Kallin, interviewed by Anna Orrghen, 10 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/7-sten-kallin.pdf"}, {"title": "Anna Orrghen, Från matematikmaskin till IT. Fokusgrupp: Media. Slutrapport. Tekniska museet, Stockholm, 2008", "url": "https://www.tekniskamuseet.se/app/uploads/2016/11/slutrapport-media-anna-orrghen.pdf"}, {"title": "Gary Svensson, Digitala pionjärer. Datakonstens introduktion i Sverige. Carlssons, Stockholm, 2000", "url": "https://libris.kb.se/8rkhln4l18j4hmr"}, {"title": "Göran Sundqvist, interviewed by Anna Orrghen, 31 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/5-goran-sundqvist.pdf"}, {"title": "Jan W Morthenson, interviewed by Anna Orrghen, 17 August 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/6-jan-w-morthenson.pdf"}, {"title": "Göran Sundqvist, “Fossil II”, “Spirals”, “Fire Bird”. Eighth Annual Computer Art Contest, Computers and Automation, August 1970, pp. 19–20", "url": "https://bitsavers.org/magazines/Computers_And_Automation/197008.pdf"}, {"title": "Elektronmusikstudion – konst, teknik och politik. Scenkonstmuseet, Stockholm", "url": "https://scenkonstmuseet.se/utstallningar/elektronmusikstudion-konst-teknik-och-politik/"}, {"title": "Lars-Gunnar Bodin, interviewed by Anna Orrghen, 5 September 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/26-lars-gunnar-bodin.pdf"}, {"title": "Lars-Gunnar Bodin, Curriculum Vitae – bild, 2009", "url": "https://semicolon.se/documents_se/Curriculum%20Vitae-bild(2009).pdf"}, {"title": "Astrid Sampe with computer programmer Sten Kallin and IBM Plotter 1627, Computer Colonne, 1975. The Art Institute of Chicago, gift of Astrid Sampe", "url": "https://www.artic.edu/artworks/107812/computer-colonne"}, {"title": "Sture Johannesson and Ann-Charlotte Johannesson, interviewed by Anna Orrghen, 2 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/4-ann-charlotte-och-sture-johannesson.pdf"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}, {"title": "Torsten Ridell, interviewed by Anna Orrghen, 21 November 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/10-torsten-ridell.pdf"}, {"title": "Artiste et ordinateur: [exposition], Paris, Lille, Caen, 1979. Centre culturel suédois, Paris, 1979. 28 pages, ill. Catalogue record, LIBRIS", "url": "https://libris.kb.se/2kc0n4nd5g0hkvz"}, {"title": "Manfred Mohr, email to JAEV, 14 October 2026", "url": null}],
   "related": {"editorial":["manfred-mohr","the-colour-cubes","generative-art","sol-lewitt"],"exhibitions":["automatic-colour-cubes"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/kallin-sampe-cross-reconstruction-jaev.jpg", "alt": "A red cross drawn thirty-four times in thin, slightly trembling plotter lines on warm paper, each smaller than the last and turned a little further, so that the crosses wind into a spiral towards the centre.", "credit": "Reconstruction by JAEV, after Sten Kallin's account of his program for Astrid Sampe: a cross drawn again and again, smaller and turned each time, by a plotter pen that sits a little loose. The number of turns, the angle and the reduction are JAEV's choices; Sampe chose her own. No image of the original is known to us. CC BY 4.0."},
   "text": "One day the textile designer Astrid Sampe, the former head of NK's textile studio in Stockholm, called IBM and asked to be put through to its design department. IBM had no design department. The switchboard passed her on to Sten Kallin, a programming teacher who was known in the company for his odd ideas: \"can you talk to this lady, she wants to draw something strange on computers and we have no idea who she should talk to.\"\n\nThe call is a small scene, but it shows how computer art came about in Sweden. In the 1960s and 70s almost no artist had a computer. The machines belonged to an aircraft maker, a power company, IBM and the universities, and were built for other work. Art was made on them when someone inside opened the door, usually in the evening, when the machines were free. What could be made, and what it looked like, depended on which machine was available and what it could draw.\n\nMost of what is known about this period comes from interviews that the historian Anna Orrghen made with ten of the people involved in 2007, for Tekniska museet's documentation project Från matematikmaskin till IT (From mathematics machine to IT). The interviews are published by the museum. They were recorded forty years after the events, and Orrghen built her choice of people on the art historian Gary Svensson's dissertation Digitala pionjärer (2000). Where possible, this text checks them against sources from the time. Quotations from the interviews are translated from Swedish; the original wording is in the list of sources.\n\nThe engineer at the door\n\nThe person who opened most doors was Göran Sundqvist. At SAAB around 1960–61, asked to impress visiting air force officers, he programmed the path of a cannonball on the D2, a prototype computer for aircraft, and showed it as dots on an oscilloscope, with a console of three dials, one of them for the angle of the gun. In the interview he calls it \"the first computer game, as people say\".\n\nThe Datasaab D2, the prototype computer for aircraft that Sundqvist programmed, at the computer museum IT-ceum in Linköping in 2007. Photo: Lars Aronsson, Wikimedia Commons, CC SA 1.0.\n\nReconstruction by JAEV: the path of a cannonball drawn as dots on an oscilloscope, at five angles of the gun, after Sundqvist's description of his program for the SAAB D2. Angles and screen are JAEV's choices; no image of the original display is known to us. CC BY 4.0.\n\nHe later looked after a computer that the power company Skandinaviska Elverk used to regulate the gates of hydroelectric dams, and composers from the Stockholm music society Fylkingen came to him to use it. Sundqvist also made pictures of his own. In August 1970 the American magazine Computers and Automation printed three of them in its eighth annual computer art contest, Fossil II, Spirals and Fire Bird. The magazine describes how they were made: drawn on a Tektronix 611 display connected to a SAAB D22, \"from a simple program to produce a circle, with different and varying parameters for radius, center coordinates, and angles.\"\n\nSound before pictures\n\nThe first lasting artistic use of these machines in Sweden was in music. For Jan W Morthenson's Neutron Star (1967) he wrote a program on the power company's D21: a random generator and a short loop that produced bursts of sound, which Morthenson then shaped into the piece at the Elektronmusikstudion (EMS), the studio that Sveriges Radio had built up from 1964 under the composer Knut Wiggen.\n\nThe interviews give two reasons why sound came first. Lars-Gunnar Bodin, composer and artist, points out that pitch, duration and loudness are easy to translate into numbers. Morthenson adds that \"sound does not take much computing power, not nearly as much as images\". There was also the price. Bodin remembers that renting computer time cost around 1,200 kronor an hour, more than any composer could pay; his own work with Sundqvist was done on the side, at night.\n\nLund, 1968: the computer decides where\n\nIn 1968 Bodin showed a computer-made picture in Lund, at En festival kring konst och teknologi (A festival around art and technology). The festival programme listed his \"serial and stochastic structures\", made with Sundqvist.\n\nBodin describes how such a picture was made. It was built from 120 or 130 small cells. He set the rules for each kind of cell and how many elements of each colour, yellow and orange, there should be. The computer decided where they went, and returned the answer as a printout of letters and coordinates. Bodin then made the picture by hand, cell by cell. The large picture made for Lund was later destroyed by water in storage.\n\nReconstruction by JAEV, after Bodin's description of his method: 121 cells, each with between 0 and 15 yellow and orange elements, their number and places drawn at random. The shape of the elements is JAEV's choice. Bodin's picture no longer exists. CC BY 4.0.\n\nThe division of labour came from the machine. The computer could choose but not paint, so the choosing was given to it and the painting stayed with the artist. It is close to what Sol LeWitt was writing in New York in the same years: the rules are the work, and the execution can be left to someone or something else.\n\nIBM's plotter in the cupboard\n\nKallin, who taught programming at IBM in Solna from 1963, had the use in the evenings and at weekends of an IBM 1130 that spent its days driving printers in a small room, and of a drum plotter that no one else in the company wanted. That is where Sampe's call ended up. She had been asked for a picture for a Red Cross charity auction and wanted to make it with a computer. Kallin wrote a program that drew the cross again and again, smaller and turned a little each time, and gave her a menu to set the number of turns, the angle and the reduction herself. They sat at the machine one evening while she tried values.\n\nThe plotter left a mark of its own. Its pen sat a little loose in the holder, so the lines were never quite straight: \"It is somehow a little human, or it has a little character or a little chance in the line.\" Laid side by side, the slightly crooked lines produced moiré.\n\nThe collaboration went on into textiles. Computer Colonne (1975), a screen-printed cotton sold by NK, is credited by the Art Institute of Chicago, which holds an example given by Sampe herself, to \"Astrid Sampe with computer programmer Sten Kallin and IBM Plotter 1627\", the drum plotter of the 1130. In a printed picture that Kallin showed in the interview, the textile is called \"one of Astrid Sampe's and IBM's computer patterns\". Kallin's name is not in that caption.\n\nOn the same kind of machine Kallin and the artist Sture Johannesson made INTRA between 1969 and 1974: curves from mathematical formulas, repeated and shifted until moiré appeared where they crossed.\n\nReconstruction by JAEV in the manner described for INTRA: curves repeated and shifted, so that moiré appears where they cross. Curves and spacing are JAEV's choices; this is not a work by Kallin and Johannesson. CC BY 4.0.\n\nLund University: letters, then ink\n\nAt the computing centre of Lund University, the duo Beck & Jung, the artist Holger Bäckström and the engineer Bo Ljungberg, worked with what the centre had. According to Bodin, there was no printer that could draw, so their first pictures were forms filled in with letters, which they then painted and joined together. In the 1970s Mikael Jern at the same centre worked with Hellmuth Hertz on a colour ink jet plotter and wrote software that drew a cube of 17 × 17 × 17 smaller cubes in graded colours. The cubes later appeared as works by Beck & Jung. Who made them is a question of its own, told in The colour cubes.\n\nMachines of their own\n\nBy around 1980 artists were beginning to have machines of their own. Sture and Ann-Charlotte Johannesson started the Digitalteatern (Digital Theatre) in Malmö at the end of the 1970s, a studio built on Apple computers that they owned. Ann-Charlotte Johannesson, trained in textiles, saw in the grid of pixels the structure of a fabric. The artist Torsten Ridell learned to program himself at the Université de Paris VIII in Vincennes, without an engineer in between.\n\nIn 1979 Ridell curated L'Artiste et l'Ordinateur (The artist and the computer) at the Centre Culturel Suédois in Paris. The 28-page catalogue names Beck & Jung, and the exhibition went on to Lille and Caen. Bodin, who took part, lists Seclin as well, and showings in Lund and Norrköping in 1980.\n\nA year earlier, Lund had a solo exhibition of computer art from abroad. From 15 November to 13 December 1978 Manfred Mohr, who drew his works at night on the plotter of the French weather service in Paris, had a solo exhibition, Dessins Génératifs, at Galerie S:t Petri, Jean Sellem's gallery for experimental art.\n\nWhat the access shaped\n\nRead side by side, the sources suggest three ways in which access decided the art.\n\nThe output device set the look. A cannonball became dots because an oscilloscope draws dots. Beck & Jung's first pictures were made of letters because the printer could print nothing else. Kallin's crosses tremble because the pen sat loose. Sundqvist's 1970 pictures are variations on one circle, made by a short program on a display terminal.\n\nTime and cost set the scale. Work was done in the evenings, on machines rented at prices no artist could pay, so the programs were short and the rules simple.\n\nAnd the work was shared. Almost every piece depended on an engineer: Sundqvist for Morthenson and Bodin, Kallin for Sampe and Johannesson, Jern for Beck & Jung. Who made what was often settled afterwards, if at all. Kallin says that he had no artistic ambitions; a museum now credits a textile to Sampe \"with computer programmer Sten Kallin and IBM Plotter 1627\".\n\nArchives and further reading\n\nWikimedia Commons: photograph of the Datasaab D2 by Lars Aronsson.\n\nTekniska museet, Stockholm: interviews with Swedish IT pioneers, in Swedish, including all the interviews used here.\n\nComputers and Automation, August 1970, with Sundqvist's three drawings: scan of the issue (Bitsavers).\n\nThe Art Institute of Chicago: Astrid Sampe, Computer Colonne, 1975.\n\nScenkonstmuseet, Stockholm: Elektronmusikstudion – art, technology and politics.\n\nJAEV made the reconstructions on this page; their captions, file names and metadata all say so. They can be used freely under CC BY 4.0 with credit to JAEV and a link back to this page."},
{"type": "editorial", "title": "The colour cubes", "url": "https://jaev.gallery/editorial/the-colour-cubes/",
   "description": "In 1970s Lund a programmer made a colour cube and two artists made it art. Who made the work? A case from early Swedish computer art. By JAEV Editorial.",
   "datePublished": "2026-10-07", "dateModified": "2026-10-07",
   "author": "JAEV Editorial",
   "about": [{"name": "computer art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1376265"}, {"name": "Holger Bäckström", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5591690"}, {"name": "Bo Ljungberg", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q19352454"}, {"name": "Mikael Jern", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q63869789"}], "mentions": [{"name": "Carl Hellmuth Hertz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q77580"}, {"name": "Sture Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5884840"}, {"name": "Charlotte Johannesson", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4956816"}, {"name": "Lund University", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q218506"}],
   "sources": [{"title": "“Beck & Ljung”. Stockholms läns museum", "url": "https://stockholmslansmuseum.se/konstnar/beck-ljung/"}, {"title": "“Bäckström, Holger (1939–1997), bildkonstnär, skulptör, grafiker, datakonstnär”. Kulturportal Lund", "url": "https://kulturportallund.se/lundaprofil_11759/"}, {"title": "Mikael Jern, interviewed by Anna Orrghen, 4 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/12-mikael-jern.pdf"}, {"title": "Original wording of the quotations from Mikael Jern (source 3)", "url": null}, {"title": "Anna Orrghen, Från matematikmaskin till IT. Fokusgrupp: Media. Slutrapport. Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2016/11/slutrapport-media-anna-orrghen.pdf"}, {"title": "“Beck och Jung”. Region Blekinge, Konst i Blekinge", "url": "https://regionblekinge.se/konst-i-blekinge/konstsamling/film---guldkorn-i-konstsamlingen/beck-och-jung.html"}, {"title": "Sture Johannesson and Ann-Charlotte Johannesson, interviewed by Anna Orrghen, 2 October 2007. Från matematikmaskin till IT, Tekniska museet, Stockholm", "url": "https://www.tekniskamuseet.se/app/uploads/2017/08/4-ann-charlotte-och-sture-johannesson.pdf"}, {"title": "Elisabeth Fagerstedt, “Beck & Jung: datakonstens pionjärer”, Elisabeth Fagerstedt konsttexter, 2012", "url": "http://elisabethfagerstedtkonsttext.blogspot.com/2012/05/beck-jung-holger-backstrom-1939-1997.html"}],
   "related": {"editorial":["computer-art-in-sweden","generative-art","sol-lewitt","casey-reas"],"exhibitions":["automatic-colour-cubes"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/colour-cube-method-corner.png", "alt": "An isometric cube built from 17 × 17 × 17 small cubes in soft printed colours, from pale yellow at the bottom through green, orange, cyan and magenta to dark blue at the top, with the nearest corner cut away.", "credit": "A colour cube made by JAEV in 2026 by following the method described in the sources: 17 × 17 × 17 cubes, three inks, a 4 × 4 dot matrix at 150 dots per inch, one corner cut away. Not one of Mikael Jern's or Beck & Jung's images."},
   "text": "In the 1970s a programmer at Lund University made an image of a cube in all the colours a new printer could produce. A few years later the same kind of cube hung, according to the programmer, on SAS aircraft and in IKEA, presented as the work of the artist duo Beck & Jung. This text does not try to decide who the colour cubes belong to. It tries to set out, as precisely as the published sources allow, who did what, and why the answer to \"who made the work?\" is not obvious.\n\nThe image alphabet\n\nBeck & Jung were the Lund artist Holger Bäckström (1939–1997) and the engineer Bo Ljungberg (1939–2007). They met in Lund and began to use computers to make art in 1966, a year after computer-generated drawings began to appear in public exhibitions in Germany and the United States, according to Stockholms läns museum; Kulturportal Lund dates their collaboration from 1965. Their first method was an \"image alphabet\" of six basic forms, which was programmed into a computer in collaboration with IBM, so that the forms could be combined into new images without end. Their first joint exhibition was held at Lunds konsthall in 1967.\n\nThe name appears in two forms. Stockholms läns museum writes Beck & Ljung; most other sources write Beck & Jung, and Jern uses both forms in the same interview. This text uses Beck & Jung except in quotations.\n\nA printer that was meant to be a copier\n\nThe cubes came from somewhere else. Mikael Jern, who studied mathematics in Lund, worked at the university's computer centre writing software for raster graphics: images built from rows of dots, first on line printers and pen plotters. At the Department of Electrical Measurements at the Lund Institute of Technology, professor Hellmuth Hertz was working on ink-jet technology: nozzles that fire a very fast stream of ink droplets, which can be switched on and off electronically to place dots on paper.\n\nAccording to Jern, Hertz was trying to build a copying machine rather than a printer for computers. Jern's idea was that the computer could create an image instead of copying one. Hertz built the plotter and Jern wrote the software. The plotter printed three colours, cyan, yellow and magenta, on top of each other at 150 dots per inch. For lighter and darker tones Jern used a matrix of four by four dots: the more of the sixteen dots printed, the stronger the colour.\n\nHow a tone is made from dots: a 4 × 4 matrix with more or fewer of its sixteen dots printed. Diagram by JAEV.\n\nThe dating is uncertain. Jern dates the cube image to 1972. In the same interview he places the building of the colour plotter in 1973–74, and the interview's summary gives his collaboration with Hertz as 1970–1976. The surviving accounts do not establish a precise date.\n\nThe cubes\n\nWith three colours, the natural way to show every combination is a cube, with one colour increasing along each edge. Jern then wrote software that could cut holes in the cube. His point was technical: in the three-dimensional computer graphics of the time, hiding the surfaces that should not be visible was one of the hardest problems, and he wanted to show that raster graphics could solve it more easily than drawings made of lines.\n\nOf the cube image, Jern says: \"This image I created myself, not the artists Beck and Jung, who were later allowed to use my technique. It was my image.\"\n\nFollowing the method\n\nAnna Orrghen's report for Tekniska museet states that Jern's program could draw a colour cube made of 17 × 17 × 17 smaller cubes. Seventeen steps along each edge is exactly what a 4 × 4 dot matrix allows: from no dots to all sixteen. Jern's interview adds how the hidden surfaces were solved, by drawing the far cubes first, and the holes and \"cake slices\" cut out of the cube.\n\nJAEV wrote a short program that follows these instructions. The image at the top of this page is one result. Where the sources say nothing, such as which corner faces the viewer, which part of the cube is cut away, the colours of the inks and the paper, the thin white lines between the cubes, or the order in which the dots of the matrix are filled, the choices are JAEV's. The result is therefore not a copy of the colour cubes but another realisation of the same method, made about fifty years later by someone who has only read about it.\n\nThe same method with three different cuts: a corner, a \"cake slice\" and three holes. Each image is 1754 × 1240 dots, an A4 sheet at 150 dots per inch, one pixel for each dot of ink. Made by JAEV.\n\nEnlarged detail. Each colour is made of dots of cyan, magenta and yellow ink; where all three fall on the same place, the dot is black. Made by JAEV.\n\nFrom computer image to artwork\n\nAccording to Jern, Beck & Jung had read about his cubes and asked whether they could use the programs that made them. He made the first ones for them. After that a programmer in Lund, Bob Wissler, ran Jern's programs for them. Beck & Jung found new ways of cutting the cubes, added backgrounds and combined them with other colours, and the cubes became the works they were best known for. Region Blekinge, which holds their work, names the series Chromo Cube. Jern's own company, UNIRAS, used the cube as its logo.\n\nWho did what, according to the published accounts, and where they disagree. Quotations translated by JAEV. Diagram by JAEV.\n\nThree accounts\n\nMikael Jern claims the image and, in the same interview, describes the collaboration warmly. \"So it was a very good collaboration,\" he says, and adds that he could not have sold the cubes himself: \"since it said Beck & Ljung on them, and it was they who could get this out as art, I could not have done that.\"\n\nSture and Charlotte Johannesson, who also worked with computers in Skåne, remembered it differently in their interview. Sture Johannesson said that Jern was \"now very angry at these Beck & Jung, who just printed out\", and Charlotte Johannesson added that Jern \"did not mean it as art\". In Sture Johannesson's words, the artists \"just took the printouts of Mikael Jern's UNIRAS logo and made prints from it\". He contrasted this with his own work with the IBM engineer Sten Kallin, where, he said, they wrote their own program for what they intended to do.\n\nBeck & Jung themselves worked in a way that made the question less central. Kulturportal Lund describes Beck & Jung as their \"artist and company name\". The art writer Elisabeth Fagerstedt goes further: in her description, the name worked as a brand, modelled on the collective working methods of advertising agencies, architects' offices and graphic design firms, and the duo set out to reduce the individual in favour of what could be shared.\n\nThese accounts do not have to cancel each other out. Jern's statements describe the image and the technique. The Johannessons' describe a judgement of what counts as artistic work. Beck & Jung's working method deliberately shifted attention away from the individual artist. What the sources do show is a chain of people and machines, each contributing something different: the artists who asked, the programmer who wrote the software, the programmer who ran it, the computer centre, the plotter and its builder, and the artists who decided which images became works and put their name on them.\n\nThe same question runs through JAEV's texts on Sol LeWitt and Casey Reas: where does the work come from when one person writes the system and another makes the result? In Lund in the 1970s it was not a theory. It was a cube on a wall, and people who remembered it differently."},
{"type": "editorial", "title": "Casey Reas", "url": "https://jaev.gallery/editorial/casey-reas/",
   "description": "Casey Reas writes his systems in English before they become code. Why the computer does not remove interpretation, but moves it. By JAEV Editorial.",
   "datePublished": "2026-10-07", "dateModified": "2026-10-07",
   "author": "JAEV Editorial",
   "about": [{"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}, {"name": "generative art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1502032"}], "mentions": [{"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "Ben Fry", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4888685"}, {"name": "Processing", "type": "SoftwareApplication", "sameAs": "https://www.wikidata.org/wiki/Q1053535"}, {"name": "Whitney Museum of American Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q639791"}],
   "sources": [{"title": "“Info”. Casey Reas, reas.com", "url": "https://reas.com/info"}, {"title": "“Casey Reas: {Software} Structures”. Whitney Museum of American Art, New York", "url": "https://whitney.org/exhibitions/software-structures"}, {"title": "“Process”. Casey Reas, reas.com", "url": "https://reas.com/process"}, {"title": "“Processing: the Software that Shaped Creative Coding”. AIGA Eye on Design", "url": "https://eyeondesign.aiga.org/processing-the-software-that-shaped-creative-coding/"}],
   "related": {"editorial":["generative-art","sol-lewitt","vera-molnar"],"exhibitions":["difficulty"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/casey-reas-2017.jpg", "alt": "Casey Reas, a man with grey hair and a beard in a dark shirt, standing in a room with papers pinned to the wall and a brown sofa.", "credit": "Casey Reas at Strelka Institute, Moscow, 2017. Photo: Andrey Noskov / Strelka Institute."},
   "text": "Casey Reas, born in 1972 in Troy, Ohio, is an artist and educator based in Los Angeles and a professor in the Department of Design Media Arts at the University of California, Los Angeles. Together with Ben Fry, he started Processing, the programming environment for artists and designers, in 2001. In 2020 he co-founded the online platform Feral File.\n\nIt is tempting to see his work as the point where the history told in JAEV's earlier texts ends: Vera Molnár's rules moved to the computer, Sol LeWitt's instructions became programs, and the machine took over. Reas's work shows something else. He writes his systems as instructions in English first, and treats the code as one interpretation of them. The computer does not remove the step where someone interprets an instruction. It moves that step earlier, to the person who writes the program.\n\nWhere the interpretation happens. Diagram by JAEV.\n\n{Software} Structures: LeWitt as software\n\nThe question first came up in a commission for Artport, the Whitney Museum of American Art's online space. Reas has described where it started: \"The catalyst for this project is the work of Sol LeWitt, specifically his wall drawings. I had a simple question: 'Is the history of conceptual art relevant to the idea of software as art?'\"\n\nHe began by implementing three of LeWitt's wall drawings in software. Then he wrote three structures of his own, which he describes as \"text descriptions outlining dynamic relations between elements\". In his words, they \"develop in the vague domain of image and then mature in the more defined structures of natural language before any thought is given to a specific machine implementation.\" Twenty-six programs were then written from these texts, by Reas together with Jared Tarbell, Robert Hodgin and William Ngan, to isolate different components of the structures, including interpretation, material and process.\n\nOne text, three programs. To write the code, each programmer has to decide what \"at random\" means. The instruction is JAEV's own example, the same as in the text on Sol LeWitt. Diagram by JAEV.\n\nProcess: a grammar for systems\n\nThe method that grew out of this became the series Process, and it is built on a small grammar. A Form is a visual primitive, such as a line or a circle. A Behavior is a rule for action, such as \"move in a straight line\". An Element is a Form combined with one or more Behaviors; Reas describes it as a simple machine. His own example is Element 1, a circle with four Behaviors: move in a straight line, constrain to surface, change direction while touching another Element, and move away from an overlapping Element.\n\nElement 1 in Reas's grammar for the Process series, set out as a diagram by JAEV from the definition on his website. The diagram shows the rules only, not the images they produce.\n\nEach work in the series is a short English text that defines an environment of Elements and how their interactions are drawn. Reas's website states the principle directly: the text is primary, \"the rules are the artwork, while software and hardware are secondary interpretations that can shift over time.\" It also says that \"to implement a Process in code is itself an act of interpretation, requiring the artist-programmer to make choices not specified in the text.\"\n\nThe programmer is in the same place as LeWitt's drafter: given words, making decisions, producing one realisation among many possible ones.\n\nThe tool for everyone else\n\nReas also made it easier for others to work this way. Processing was started by Ben Fry and Reas while both were connected to the Aesthetics and Computation Group at the MIT Media Lab. It was meant to make programming more accessible to artists and designers. It put the means of writing a system into many more hands.\n\nWhat changes with code\n\nCode does change some things. A program can run indefinitely and produce an endless series of images from the same rules. Reas's website describes what this meant for the artist: \"the artist's role was not to compose pictures, but to define systems.\"\n\nBut code also ages. The programs for {Software} Structures were first written as Java applets, which modern web browsers no longer support; in 2016 Reas restored the project in JavaScript so that it could run again. His website describes hardware as \"incidental—fragile and replaceable—while the instructions endure as the work's essence.\"\n\nThat is where the chain from Molnár and LeWitt leads, and it continues past code: a program is one more realisation of an instruction, made by someone who had to interpret it, and it can be made again when the machines change."},
{"type": "editorial", "title": "Sol LeWitt", "url": "https://jaev.gallery/editorial/sol-lewitt/",
   "description": "Sol LeWitt's wall drawings exist as instructions that other people carry out. What that means for authorship, variation and execution. By JAEV Editorial.",
   "datePublished": "2026-10-07", "dateModified": "2026-10-07",
   "author": "JAEV Editorial",
   "about": [{"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "conceptual art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q203209"}], "mentions": [{"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}, {"name": "Whitney Museum of American Art", "type": "Organization", "sameAs": "https://www.wikidata.org/wiki/Q639791"}],
   "sources": [{"title": "“Wall Drawing #118: 50 randomly placed points connected by straight lines”, Sol LeWitt, 1971. Art Institute of Chicago", "url": "https://www.artic.edu/artworks/196148/wall-drawing-118-50-randomly-placed-points-connected-by-straight-lines"}, {"title": "Anna Lovatt, “Ideas in Transmission: LeWitt’s Wall Drawings and the Question of Medium”, Tate Papers no. 14, Tate, London, 2010", "url": "https://www.tate.org.uk/research/tate-papers/14/ideas-in-transmission-lewitt-wall-drawings-and-the-question-of-medium"}, {"title": "Sol LeWitt, “Paragraphs on Conceptual Art”, Artforum, June 1967", "url": "https://monoskop.org/images/3/3d/LeWitt_Sol_1967_1999_Paragraphs_on_Conceptual_Art.pdf"}, {"title": "Sol LeWitt, “Sentences on Conceptual Art”, 1969", "url": "https://monoskop.org/images/3/3d/LeWitt_Sol_1969_1999_Sentences_on_Conceptual_Art.pdf"}, {"title": "Sol LeWitt, “Doing Wall Drawings”, 1971. Reprinted in Gary Garrels (ed.), Sol LeWitt: A Retrospective, San Francisco 2000, p. 376", "url": null}, {"title": "“Peace or misery: The making of a Sol LeWitt wall drawing”. Walker Art Center, Minneapolis", "url": "https://www.walkerart.org/reader/peace-or-misery/"}, {"title": "“Wall Drawing #4”, Sol LeWitt. Cleveland Museum of Art", "url": "https://www.clevelandart.org/art/2008.144"}, {"title": "“Sol LeWitt: Cubic Forms”. Paula Cooper Gallery, New York", "url": "https://www.paulacoopergallery.com/exhibitions/sol-lewitt13"}, {"title": "“Casey Reas: {Software} Structures”. Whitney Museum of American Art, New York", "url": "https://whitney.org/exhibitions/software-structures"}],
   "related": {"editorial":["manfred-mohr","generative-art","vera-molnar"],"exhibitions":["automatic-colour-cubes","group-photos"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/one-instruction-three-executions.png", "alt": "A diagram with one written instruction, Place twenty points at random. Connect each point to its two nearest points, and below it three square drawings of points and lines, each different.", "credit": "One instruction, three executions. Diagram by JAEV. The instruction is JAEV's own example, not a work by Sol LeWitt."},
   "text": "Sol LeWitt (1928–2007) was an American artist. Many of his works are wall drawings, made on the wall by other people following his instructions. This text takes that practice as an argument: that a work can be defined as a system of instructions, and that its execution can be handed to someone else. The question is what then happens to authorship, to variation and to the drawing itself.\n\nThe idea as a machine\n\nLeWitt set out the principle himself. In \"Paragraphs on Conceptual Art\", published in Artforum in 1967, he wrote that in this kind of art \"all of the planning and decisions are made beforehand and the execution is a perfunctory affair. The idea becomes a machine that makes the art.\" Two years later, in \"Sentences on Conceptual Art\", he went further: \"Once the idea of the piece is established in the artist's mind and the final form is decided, the process is carried out blindly.\"\n\nHe gave a practical reason too. \"To work with a plan that is pre-set is one way of avoiding subjectivity. It also obviates the necessity of designing each work in turn.\"\n\nThese statements are strong, and LeWitt's own practice was less absolute than they sound. But they describe the logic that makes the wall drawings possible: the decisions are taken in the instruction, and the instruction is what is kept.\n\nOne instruction, many drawings\n\nWall Drawing #118 from 1971 is a clear example. Its title, as the Art Institute of Chicago records it, summarises the instruction: 50 randomly placed points connected by straight lines. The instruction does not say where the points go. That is left to the person who draws it, on that wall, on that day. Every time the work is installed, it is the same work and a different drawing.\n\nLeWitt knew that the instruction would not pass through unchanged. In his text \"Doing Wall Drawings\" (1971) he wrote that \"each person draws a line differently and each person understands words differently\", and that \"the draftsman perceives the artist's plan, then reorders it to his own experience and understanding.\" The variation was part of the system, not a flaw in it.\n\nThe diagram at the top of this page makes the same point with an invented instruction. All three panels follow the same words. Only the person following them, here simulated by a different random choice of points, has changed.\n\nThere is a second layer of variation: the hand. Even with exactly the same points, a line drawn with a ruler and a hard pencil is not the line drawn freehand with a softer one.\n\nThe same execution drawn three ways. Diagram by JAEV.\n\nWho makes the work?\n\nLeWitt installed his first wall drawing himself. From 1969 he began to ask friends, curators and collectors to install the drawings according to his instructions, and later employed a team of specialist technicians. The Walker Art Center describes the group of assistants he trusted to carry out his instructions.\n\nThe wall drawings also changed what it means to own a work, and the Cleveland Museum of Art explains how: LeWitt \"developed a system of ownership by which the buyer of the drawing receives a certificate and a rendering with directions for any other drafter to use.\" The owner holds not the pencil on the wall but the right to make it, together with the instructions.\n\nAuthorship is divided from execution. LeWitt is the author of the work: he decided what it is and how it is to be made. The drafters realise it, making the decisions the instruction leaves open, and their hands are visible in the result. Neither role can be reduced to the other.\n\nWorking through every possibility\n\nInstructions can also be used to exhaust a set of possibilities rather than to leave choices open. Variations of Incomplete Open Cubes (1974) \"proposes all of the 122 variations in which a cube can be incomplete\". Here the system does not invite interpretation. It defines a complete series, and each object is identified by its place in it.\n\nEvery way to draw or leave out the four sides of a square: two choices for each side, sixteen results. A simpler system than LeWitt's cubes, made by JAEV to show the principle.\n\nThe two approaches belong together. In one, the rule is fixed and the execution varies. In the other, the rule produces every variation itself. Both make the system, rather than a single composition, the centre of the work.\n\nFrom instruction to code\n\nAn instruction that anyone can follow is close to a program. The artist Casey Reas made the connection explicit: his project {Software} Structures, presented by the Whitney Museum of American Art, began by implementing three of LeWitt's wall drawings in software, to ask whether the history of conceptual art is relevant to the idea of software as art.\n\nPlace twenty points at random. Connect each point to its two nearest points.\n\npoints = random_points(20)\nfor p in points:\nfor q in nearest(p, points, 2):\nline(p, q)\n\nThe instruction from the top of this page, as words for a person and as a few lines of code for a computer. The diagrams on this page were drawn by a fuller version of it.\n\nWhat changes when the instruction becomes code is the executor. A person reads the words and interprets them; software executes formalised instructions, with variation supplied by whatever choices, inputs or chance operations the program allows. LeWitt's wall drawings show what an instruction can hold before that step: an idea precise enough to be handed over, and open enough to be different every time."},
{"type": "editorial", "title": "Vera Molnár", "url": "https://jaev.gallery/editorial/vera-molnar/",
   "description": "Vera Molnár worked with rules and chance for ten years before she had a computer. How her imaginary machine became a real one. By JAEV Editorial.",
   "datePublished": "2026-10-06", "dateModified": "2026-10-06",
   "author": "JAEV Editorial",
   "about": [{"name": "Vera Molnár", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1658002"}, {"name": "generative art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1502032"}], "mentions": [{"name": "Albrecht Dürer", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5580"}, {"name": "Katsushika Hokusai", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5586"}, {"name": "Paul Cézanne", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q35548"}, {"name": "Centre Pompidou", "type": "Organization", "sameAs": null}],
   "sources": [{"title": "Stéphanie Pioda, “Vera Molnár, aux sources du code”. Centre Pompidou, Paris, 2023", "url": "https://www.centrepompidou.fr/en/pompidou-plus/magazine/article/vera-molnar-aux-sources-du-code"}, {"title": "“Vera Molnár”. AWARE: Archives of Women Artists, Research and Exhibitions", "url": "https://awarewomenartists.com/en/artiste/vera-molnar/"}, {"title": "Zarna Hart, “Vera Molnar: Machine Imaginaire – the dance of hands and machine thinking”. Victoria and Albert Museum, London, 2024", "url": "https://www.vam.ac.uk/blog/museum-life/vera-molnar-machine-imaginaire-the-dance-of-hands-and-machine-thinking"}],
   "related": {"editorial":["generative-art"],"exhibitions":["difficulty"],"artists":[],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/vera-molnar-parler-a-loeil-centre-pompidou-2024.jpg", "alt": "A white wall with the words Vera Molnár and Parler à l'œil in large dark red letters, and the dates 28.02 – 26.08.24.", "credit": "Entrance to Vera Molnár: Parler à l'œil, Centre Pompidou, Paris, 2024. Photo: Jean-no."},
   "text": "Vera Molnár (1924–2023) is often described as a pioneer of computer art. That is true, but it leaves out the most interesting part of her story. For about ten years before she ever used a computer she was already making work from rules she had written herself, with chance deciding whatever the rules left open. She had the method first, so when the machine arrived there was no new way of thinking for her to learn.\n\nVera Molnár in 1996. Still from a video for the Encyclopédie audiovisuelle de l'art contemporain. Photo: Pantalaskas, CC BY-SA 3.0. Source\n\nVariation before the computer\n\nShe was born Vera Gács in Budapest. As a teenager, she found two books in an antiques shop that stayed with her: one with Albrecht Dürer's engraving Melencolia I, and one on the Japanese artist Hokusai, which she bought, as she later said, because it contained so many variants of Mount Fuji. The same motif, drawn again and again with small changes, would become the subject of her own work.\n\nAlbrecht Dürer, Melencolia I, 1514. The Metropolitan Museum of Art, New York. CC0. Source\n\nKatsushika Hokusai, Fine Wind, Clear Morning and Kajikazawa in Kai Province, from the series Thirty-six Views of Mount Fuji, around 1830. Public domain (source) and The Metropolitan Museum of Art, CC0 (source).\n\nShe entered the School of Fine Arts in Budapest in 1942 and wrote her final thesis on Cézanne and Cubism. In 1947 she left Hungary with François Molnár, a fellow student whom she married the following year, and they settled in Paris.\n\nParis and concrete art\n\nIn Paris she turned to geometric abstraction and concrete art: painting made of simple shapes, planned in advance, that refers to nothing outside the picture. Her titles simply describe what is there, as in 3 carrés noirs, 3 rectangles gris, 5 rectangles bleu (3 black squares, 3 grey rectangles, 5 blue rectangles) from 1950.\n\nThe imaginary machine\n\nFrom 1959 she worked with what she called a machine imaginaire, an imaginary machine. It was a simple program, carried out by hand: a set of instructions and prohibitions that transformed a shape step by step. She chose the shapes, colours and materials, followed the rules, and drew the results she wanted to keep on a roll of paper. The Victoria and Albert Museum describes how she often worked on a grid, with rules for colour, shape, line and direction, which let her work systematically through the possible permutations of a series.\n\nOne of the earliest works made this way is Quatre éléments distribués au hasard (Four elements distributed at random) from 1959: a square of geometric shapes made with strips of black adhesive film glued to white board. The title states the method. The rule fixes the elements; chance decides where they go.\n\nThe imaginary machine already contained the basic logic of a computer program: a defined set of parts, rules for changing them, a source of randomness and a series of results. Only speed was missing.\n\n1968: the real machine\n\nIn 1968, while student protests filled the streets of Paris, she gained access, in complete secrecy, to a computing centre in Orsay. She later described what it meant: \"You cannot imagine the emotion of seeing appear on the screen, for the first time, what exists naturally in your brain. Then you only have to press a few keys to make a correction, or to move a shape to the right or to the left.\"\n\nA Calcomp 565 drum plotter from around 1966, a type of machine that drew computer output with a pen on a roll of paper. Photo: Ryan Somma, CC BY-SA 2.0. Source\n\nWhat she was looking for stayed the same; the computer let her look faster. The Centre Pompidou puts it plainly: for her the computer was a tool for exploring possible combinations and selecting the forms that met her own visual standards, not an object of technical fascination. Plotter drawings from this period, such as Interruptions (1969), are now in museum collections, including the V&A in London.\n\nOrder and one per cent disorder\n\nIn 1974 she and François Molnár wrote a program they called Molnart. It composed images from sets of squares whose sides she could alter, and it let her add a chosen percentage of irregularity, a kind of planned clumsiness, so that the drawing would not look mechanical. The idea became one of her trademarks under the name 1 % de désordre, one per cent disorder: a regular system, disturbed by a deliberately controlled amount of irregularity. The V&A holds plotter drawings from the same year, (Des)Ordres and Structure of Squares.\n\nThe rules were the artist's, as were the amount of chance and the choice of which results counted as works. The computer left that judgement in her hands. It let her set the amount of disorder precisely, run the system many times and see the whole range of results.\n\nHand and machine\n\nMolnár never stopped drawing by hand. She worked by a rule she had set herself long before: pas une journée sans une ligne, not a day without a line. She also returned to the images she had loved since her student years. In a series on the Montagne Sainte-Victoire, the mountain Cézanne painted many times, she tore paper as well as drawing lines.\n\nPaul Cézanne, two views of Mont Sainte-Victoire, around 1892 and around 1900. Barnes Foundation, Philadelphia. Public domain (source, source).\n\nRecognition came late. According to the Centre Pompidou, she did not begin to sell her work until after François Molnár's death in 1993, and in 2022 she released her first work as an NFT, 2 % de désordre. She died in Paris on 7 December 2023, aged 99. A few months later the Centre Pompidou opened a large exhibition of her work, Parler à l'œil (Speaking to the eye).\n\nWhy it matters\n\nMolnár's work is the clearest case for the view taken in JAEV's text on generative art: that the system is part of the artistic material. Her imaginary machine was a system before there was a machine to run it. When the real machine came, it took over the execution, and the idea, the rules and the one per cent of disorder remained hers."},
{"type": "editorial", "title": "Generative Art", "url": "https://jaev.gallery/editorial/generative-art/",
   "description": "What generative art is: art made through rules, systems and processes, from instructions on paper to programs. Why it matters to JAEV in Lund.",
   "datePublished": "2026-10-06", "dateModified": "2026-10-06",
   "author": "JAEV Editorial",
   "about": [{"name": "generative art", "type": "Thing", "sameAs": "https://www.wikidata.org/wiki/Q1502032"}], "mentions": [{"name": "Philip Galanter", "type": "Person", "sameAs": null}, {"name": "François Morellet", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q667780"}, {"name": "Sol LeWitt", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q168587"}, {"name": "Vera Molnár", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1658002"}, {"name": "Georg Nees", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5535768"}, {"name": "Max Bense", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q62373"}, {"name": "A. Michael Noll", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4648184"}, {"name": "Béla Julesz", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q1019423"}, {"name": "Manfred Mohr", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q872832"}, {"name": "Casey Reas", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q5006090"}, {"name": "Ben Fry", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q4888685"}, {"name": "Processing", "type": "SoftwareApplication", "sameAs": "https://www.wikidata.org/wiki/Q1053535"}, {"name": "Olof Broström", "type": "Person", "sameAs": "https://www.wikidata.org/wiki/Q141135403"}],
   "sources": [{"title": "Philip Galanter, “What is Generative Art? Complexity Theory as a Context for Art Theory”, 2003", "url": "https://philipgalanter.com/downloads/ga2003_paper.pdf"}, {"title": "Anleitung Walzer oder Schleifer mit zwei Würfeln zu componieren, N. Simrock, Bonn. Bibliothèque nationale de France (Wikimedia Commons)", "url": "https://commons.wikimedia.org/wiki/File:Valses_pour_piano._Anleitung_Walzer_oder_Schleifer_mit_zwei_W%C3%BCrfeln_zu_componieren..._-_btv1b10886993w_(02_of_10).jpg"}, {"title": "François Morellet, Répartition aléatoire de 40 000 carrés d’après les chiffres pairs et impairs d’un annuaire de téléphone, 1961. Annely Juda Fine Art, London", "url": "https://www.annelyjudafineart.co.uk/artworks/38071-francois-morellet-repartition-aleatoire-de-40-000-carres-d-apres-les-1961/"}, {"title": "Sol LeWitt, “Paragraphs on Conceptual Art”, Artforum, June 1967", "url": "https://monoskop.org/images/3/3d/LeWitt_Sol_1967_1999_Paragraphs_on_Conceptual_Art.pdf"}, {"title": "“Peace or misery: The making of a Sol LeWitt wall drawing”. Walker Art Center, Minneapolis", "url": "https://www.walkerart.org/reader/peace-or-misery/"}, {"title": "“Vera Molnár, aux sources du code”. Centre Pompidou, Paris", "url": "https://www.centrepompidou.fr/en/pompidou-plus/magazine/article/vera-molnar-aux-sources-du-code"}, {"title": "Zarna Hart, “Vera Molnar: Machine Imaginaire – the dance of hands and machine thinking”. Victoria and Albert Museum, London, 2024", "url": "https://www.vam.ac.uk/blog/museum-life/vera-molnar-machine-imaginaire-the-dance-of-hands-and-machine-thinking"}, {"title": "“The Earliest Public Exhibitions of Computer Art”. HistoryofInformation.com", "url": "https://www.historyofinformation.com/detail.php?entryid=3921"}, {"title": "“Max Bense”. ZKM Center for Art and Media, Karlsruhe", "url": "https://zkm.de/en/persons/max-bense"}, {"title": "“Georg Nees”. ZKM Center for Art and Media, Karlsruhe", "url": "https://zkm.de/en/persons/georg-nees"}, {"title": "Manfred Mohr, “Computer Graphics: Une Esthétique Programmée, Paris 1971”", "url": "https://www.emohr.com/paris-1971/index.html"}, {"title": "“Processing: the Software that Shaped Creative Coding”. AIGA Eye on Design", "url": "https://eyeondesign.aiga.org/processing-the-software-that-shaped-creative-coding/"}, {"title": "“Casey Reas: {Software} Structures”. Whitney Museum of American Art, New York", "url": "https://whitney.org/exhibitions/software-structures"}],
   "related": {"editorial":["georg-nees","sol-lewitt","vera-molnar","manfred-mohr","casey-reas","computer-art-in-sweden"],"exhibitions":["difficulty","group-photos","automatic-colour-cubes"],"artists":["olof-brostrom"],"works":[]},
   "image": {"url": "https://jaev.gallery/assets/editorial/musikalisches-wurfelspiel-zahlentafel-simrock.jpg", "alt": "A printed page with two tables of numbers, headed Zahlentafel and Table de Chiffres. Rows are numbered 2 to 12, columns A to H.", "credit": "Number table from an instruction for composing waltzes with two dice, published under the name of W. A. Mozart by N. Simrock, Bonn. Bibliothèque nationale de France. Public domain."},
   "text": "Generative art is art made through rules, systems and processes. The artist need not determine every line, sound or colour individually, and instead decides how the work will be made, by writing instructions, a program or a set of rules, or by building a machine, and lets that process produce the result. The artist and theorist Philip Galanter has described it as any practice in which the artist sets a system in motion and the system, with some degree of independence, contributes to the finished work.\n\nThe view taken here is that in generative art the system is part of the artistic material, alongside paint, paper or code. That matters to JAEV because the gallery's own server is used as such a system. Works are not only shown on it; they are made on it, every day.\n\nWhat a system can be\n\nA generative work usually combines a few of these parts.\n\nRules or instructions. A precise description of what to do: draw a line from here to there, repeat it ten times, turn it a few degrees each time. Rules can be written in ordinary language or in a programming language.\n\nChance. A source of unpredictable choices: dice, digits from a list, or random numbers produced by a computer. Chance decides what the rules leave open.\n\nRepetition and variation. The same rules are run many times, and each run gives a different result. The individual results are variations of one idea.\n\nSeries and permutations. A permutation is one of the possible ways to order or combine a fixed set of parts. Working through all of them, or many of them, gives a series in which every work belongs to the same family.\n\nInput. Some systems take in information from outside, such as measurements, texts or images, and turn it into form.\n\nThe artist decides which of these to use and how they work together, and the result is often a family of possible works rather than a single one.\n\nThe image at the top of this page is an early example of a generative system, though not generative art in today's sense. It is the number table from a game for composing a waltz with two dice, sold by the music publisher N. Simrock in Bonn under the name of W. A. Mozart. Each column, A to H, is one bar. The player throws two dice and plays the bar whose number stands in the row for the total. Someone wrote the bars and the table; the dice choose the music.\n\nNumbered bars from the same game. The table chooses which of them are played. N. Simrock, Bonn. Bibliothèque nationale de France. Public domain. Source\n\nThe system as material, before the computer\n\nIn the twentieth century some artists began to treat the system as part of the work, at times as its most important part, and they did this without computers.\n\nFrançois Morellet used chance to take decisions away from personal taste. In Répartition aléatoire de 40 000 carrés (Random distribution of 40,000 squares) from the early 1960s, the colour of each of 40,000 squares in a grid is decided by whether a digit in a telephone directory is odd or even.\n\nSol LeWitt used instructions. In \"Paragraphs on Conceptual Art\", which Artforum published in 1967, he wrote that in his kind of art \"all of the planning and decisions are made beforehand and the execution is a perfunctory affair. The idea becomes a machine that makes the art.\" His wall drawings exist as a diagram and a set of written instructions, and assistants draw them on the wall by following those instructions. LeWitt is not a generative artist in the usual sense, and chance was not the point for him. But his work made it clear that a set of instructions can be an artwork in its own right. See Sol LeWitt.\n\nVera Molnár worked in a similar way from 1959. She called her method a machine imaginaire, an imaginary machine: a simple program of rules and prohibitions that she carried out by hand. By the time she gained access to a real computer in 1968, the method was already in place, and the machine took over the execution, not the idea. See Vera Molnár.\n\nComputer art becomes public, 1965\n\nIn the 1960s computers were large, expensive machines, and access to them was mostly reserved for scientific research and the military. A few of those who had that access began to use them for drawings, which were made by plotters: machines that move a pen across paper under the computer's control.\n\nA Zuse Graphomat Z64, a flatbed plotter from the early 1960s, in a museum display. Photo: Steve Parker, 2006, CC BY 2.0. More in JAEV's guide to plotter art.\n\nIn 1965 computer-generated drawings began to turn up in public exhibitions, in Europe and in the United States. In February works by the mathematician Georg Nees went on show at the Technische Hochschule Stuttgart, in an exhibition that the philosopher Max Bense opened. In April, at the Howard Wise Gallery in New York, A. Michael Noll and Bela Julesz of Bell Labs showed Computer-Generated Pictures.\n\nThe word generative was already in use in this circle. Bense published a short text called \"Projekte generativer Ästhetik\" (Projects of generative aesthetics) in 1965, and Nees's doctoral thesis of 1969 was called Generative Computergraphik.\n\nIn 1971 the Musée d'Art Moderne de la Ville de Paris showed Manfred Mohr's Une esthétique programmée (A programmed aesthetic), which Mohr describes as the first solo exhibition of digital art in a museum. See Manfred Mohr.\n\nSoftware as material\n\nFor decades, working with a computer meant working where the computers were: at universities, research laboratories and large companies. Personal computers changed that, and artists could write programs at home. But most programming languages were still made for engineers. Processing, started in 2001 by Casey Reas and Ben Fry, was meant to make programming more accessible to artists and designers, and it is free. Reas has also connected this work back to conceptual art: his project {Software} Structures, presented by the Whitney Museum of American Art, began by turning three of LeWitt's wall drawings into software. See Casey Reas.\n\nGenerative art and generative AI\n\nThe two terms are often confused. Generative AI systems produce new outputs using models trained on large collections of existing material.\n\nGenerative art usually starts from the other end. The artist designs the process, and can in principle explain how it works and why. The line is not always sharp, since some artists build their own learning systems. But a trained model and a designed system are different starting points, and generative art did not begin with AI.\n\nHow to look at a generative work\n\nWhat is the rule? Many works state it in the title or in an accompanying text.\n\nHow large is the range of possible results? Some systems produce small differences, others very different results from the same rules.\n\nWhere does chance come in, and where does input come in? A system can be closed, or it can take in information from the world.\n\nWhat did the artist decide? The artist chooses the rules, but also which results to show, how many, at what size, and in what form: on a screen, as a print, or drawn with ink by a plotter.\n\nAt JAEV\n\nJAEV shows generative work made on the gallery's own server. Three ongoing series by Olof Broström are systems of this kind, each with a rule that can be stated in a sentence:\n\nDifficulty: one drawing per day, made automatically from the day's aurora forecast and the day's first block in a public ledger.\n\nGroup Photos: once a day, ten nature photographs taken by different people on the same day are combined into one image.\n\nUnverified Air: one drawing per day for a year, of the buildings around a European air quality station, with the previous day's highest nitrogen dioxide and ozone drawn as hatching.\n\nOlof Broström, Difficulty no. 970100, Group Photo 0096 and Unverified Air no. 1, 2026. Courtesy of JAEV. The photographs in Group Photo 0096 and their licences are listed on the work's page.\n\nEach of them takes in information from outside, so the resulting work is partly determined by conditions that JAEV does not control. The questions above apply to them as much as to Morellet's squares."}
  ]
}