Lecturer: Tobias Zimmer 
Credits: 6 [[ECTS]], 4 [[SWS]] 
Date: Friday, 13:30 – 16:45 
Venue: [[Marienstraße 7b]], Raum 102

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==Description==
Waiting at traffic lights, shopping online, finding a new partner, baking a cake - noticed or unnoticed, everyone is in contact with algorithms each day.

In the class Algorithmic Art we will focus on graphical algorithms and generative art, to learn how to think like a machine. The programming language Processing offers artists and designers the chance to go beyond predefined and often limiting software and allows them to create their very own tools for 2D or 3D graphics production, interactive installations, data manipulation and more. With a simplified syntax, Processing takes down high entry barriers that are usually associated with programming languages. Simple visual results are possible with just a few lines of code, with an open end to more complex output and rule systems.

We will orient ourselves to the pioneering work of early computer artists (”Algorists”) like Vera Molnar, Manfred Mohr or Frieder Nake and use a pen-plotter (self built in class or a ready-made one) to materialize the algorithms we develop in homeworks or in class. Treated topics and programming basics include: 2D shapes and geometry, variables, arrays, loops, randomness, noise, interaction, animation, functions, object orientation, working with data (image, sound, text),...

Further topics depending on interest:webcam interaction, openCV, working with libraries and API’s, 3D graphics, communication (OSC), projection mapping,…

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==Introductory Algorithm==
[[File:intro_algorithm_600x600.gif|Introductory Algorithm]]

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==Working with the Plotter==
* [[/HP 7475A/]]

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==Student Works ==
* [[/Tobias Zimmer/]]
* [[/Christopher Heiden/]]
* [[/Baiyao Lin/]]
* [[/Ozan Akkoyun/]]
* [[/Grayson Daniel Bailey/]]
* [[/Leon Billerbeck/]]
* [[/Manuel Hartmann/]]
* [[/Yasmin Mukino/]]
* [[/Hilde Karin Braunschweig/]]
* [[/Joel Schäfer/]]
* [[/Lorenz Gunreben/]]
* [[/Lucia Schmidt/]]
* [[/Michael Wilde/]]
* [[/F a b i a n K r z i c h/]]
* [[/Jonas Obertüfer/]]

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==Resources==
'''Processing'''
*[https://processing.org/reference/ Processing Reference]
*[https://processing.org/examples/ Processing Examples] you can also conveniently find these in the Processing IDE)
*Processing Cheatsheet [https://cdn.sparkfun.com/assets/6/3/f/e/3/Processing_Cheatsheet_Update.pdf] [https://www.cs.bham.ac.uk/~cxp291/ri/processing_cheat_sheet_english.pdf]
* 25 Life Saving Tips for Processing [https://amnonp5.wordpress.com/2012/01/28/25-life-saving-tips-for-processing/] [https://forum.processing.org/one/topic/25-life-saving-tips-for-processing-blogpost.html]
 
'''Relevant Texts'''
*[http://www.verostko.com/algorist.html The Algorists, ''Roman Versotko'']
*Ten theses about software art, ''Florian Cramer'' [http://cramer.pleintekst.nl/essays/10_thesen_zur_softwarekunst/10_theses_about_software_art.html english], [https://www.netzliteratur.net/cramer/thesen_softwarekunst.html german]
*Do it, ''Hans Ulrich Obrist'' (you can find the book in the library)
*[http://www.charlesgmiller.com/teaching/177/DOIT.pdf Art by instruction and the pre-history of do it, ''Bruce Altshuler'']
 
'''Early Computer Artists'''
*[http://dam.org/artists/phase-one Digital Art Museum]
*[http://dada.compart-bremen.de/ Compart Bremen]
 

'''Other artists working with code'''
*[http://reas.com/ Casey Reas]
*[https://img.inconvergent.net/plot/ Anders Hoff]
*tbc...

 
'''Inspirations'''
*[https://www.openprocessing.org/ Open Processing]
*[https://processing.org/exhibition/ Processing Exhibition]
*[https://www.creativeapplications.net/ Creative Applications]
*[http://prostheticknowledge.tumblr.com/ Prosthetic Knowledge]

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==Treated Topics==

'''12.10.18'''
* Sol LeWitt | [https://massmoca.org/sol-lewitt/ Wall Drawings]
* Casey Reas | [http://reas.com/notation/ Notation]

 '''19.10.18'''
*[https://en.wikipedia.org/wiki/Concrete_art Concrete Art Manifesto]
*''2D Geometry''

 '''26.10.18'''
*''Variables''
*''Iteration / Animation''
*''For Loops''
*''Nested For Loops''

 '''02.11.18''' 
'''Art without author!? / Artists working with randomness'''
*Jackson Pollock
*Gerhard Richter | [https://www.gerhard-richter.com/de/art/paintings/abstracts/colour-charts-12 Colour Charts] | [https://www.gerhard-richter.com/en/art/paintings/abstracts/colour-charts-12/4096-colours-6089/?&referer=search&title=4096&keyword=4096 4096 Colors]
*Henri Michaux | [https://www.google.de/search?q=henri+michaux+mescaline+drawings&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiV5tbI8cHeAhWPPFAKHW82DTYQ_AUIDigB&biw=1097&bih=554 Mescaline Drawings] 
*John Cage | [https://www.youtube.com/watch?v=B_8-B2rNw7s Music of Changes] | [https://www.youtube.com/watch?v=zvUoHxdZs4o&feature=youtu.be&t=148 I Ching (1)] | [https://www.youtube.com/watch?v=uyjOnqzjqpc I Ching (2)]
 
*RAND Corporation | [https://www.youtube.com/watch?v=bvLD54GnOTk 1.000.000 Million Random Digits]
*Global Consciousness Project - Meaningful Correlations in Random Data | [http://noosphere.princeton.edu/ Website]
*Studio Nand | [https://nand.io/projects/known-unknowns The Known Unknowns]

*''translate()''
*''scale()''
*''rotate()''
*''random()''
*''Arrays''

 '''09.11.18'''
* Anastasis Germanidis | [http://agermanidis.com/#randomly-generated-social-interactions Randomly Generated Social Interactions]

*''noise()'' – 1D, 2D
*''sin(), cos()'' – adressing points in a circular coordinate system
*''map()''

 '''16.11.18''' 
'''Drawing Machines by...'''
*[https://www.youtube.com/watch?v=cf7woGFW-Tc Jean Tuingely]
*[http://www.timknowles.co.uk Tim Knowles]
*[http://www.dwbowen.com David Bowen]
*[http://olafureliasson.net/archive/artwork/WEK108599/connecting-cross-country-with-a-line#slideshow Olafur Eliasson]
*[http://www.smigla-bobinski.com/english/works/ADA/index.html Karina Smigla-Bobinski]
*[http://sougwen.com Sougwen Chung]
*[https://www.nature.com/articles/464681b Die Helmholtz Kurven] | [https://aphelis.net/etienne-jules-marey-myograph/ Improved Myograph / Frog Drawing Machine]
 
*Getting started with the Plotter (HP7475A)
*''HPGL library''

 '''23.11.18'''
*Classes (balloons and particles reacting to two dimensional noise)
*''ArrayList''

 '''30.11.18'''
*''PImage''
*''get(x,y), get(x,y,w,h), brightness(), saturation(), red(), green(), blue()''

 '''07.12.18'''

 '''14.12.18'''

 '''21.12.18'''

 '''11.01.18'''

 '''18.01.18'''

 '''25.01.18'''

 '''01.02.18'''

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==Future Topics==

* PVector
* Export svg files
* ''noise()'' – 3D
* Working with images
* Working with sound
* Working with text
* Working with the webcam
* 3D
* OSC
* Recursion
* L-Systems

[[Category:WS18]]

2018-11-19T13:51:15Z

Tobiaszimmer: /* How to use the HPGLGraphics library in a Processing sketch? */

=='''Working with the HP 7475A'''==
==='''General'''===
The plotter is placed in room 204, in the shelf behind the projection screen. Take it out, place it on a desk and connect the serial adapter to your computer. Please do not forget to return it to the shelf when you are done! You have to bring your own pens and paper. Expect that some trial and error is involved when working with the HP7475A, until you achieve perfect results.

==='''Working Times'''===
If you want to work with the plotter, first check if the room is currently unoccupied. If you want to be sure that no one else is working with the plotter, make sure to send a message to the whole class, with the date and time that you intend to use the plotter (Email, Telegram, WhatsApp!?) 
[https://www.uni-weimar.de/qisserver/rds?state=wplan&act=Raum&pool=Raum&show=plan&P.subc=plan&raum.rgid=2847 Class Schedule in M7 Room 204]

==='''Paper Setup'''===
The HP7475A either takes A4 or A3 paper. The thickness of the paper is very flexible.

==='''Pen Setup'''===
To use your own pens with the plotter, you can simply extend your pen’s diameter, by wrapping some paper around it. This way it will fit the pen mount of the plotter. A better way would be to 3D print adaptors, that exactly fit the original HP pen measurements. Unless you have a pen that mimmicks the original HP pen shape, avoid the HPGL commands SP; SP1; SP2; SP3; SP4; SP5; SP6; as they attempt to change the pen. 
[https://softsolder.com/2015/04/21/hp-7475a-plotter-oem-pen-body-model/ Original HP pen measurements and openSCAD code]

==='''Serial Connection'''===
You need to find out the COM port, as which the USB/Serial adaptor was registered in your computer. In Windows, you can find out in the Device Manager, in Mac OS, I don’t know yet.

==='''HPGL'''===
The plotter only understands HPGL (Hewlett Packard Graphics Language). You can try the “HP7475A_live_input” sketch, to test some HPGL commands. You can find documentation about that language here: 
[https://www.isoplotec.co.jp/HPGL/eHPGL.htm Simple but incomplete reference] 
[https://archive.org/details/HP7475AInterfacingandProgrammingManual Full original reference (PDF)] 
[https://archive.org/stream/HP7475AInterfacingandProgrammingManual/HP7475AInterfacingandProgrammingManual_djvu.txt Full original reference (txt)] 

Fortunately, there is a HPGL library for Processing, which can convert your sketches to HPGL files.

Another approach is to export a .svg file with Processing and to convert it to .hpgl with InkScape. (The files produced by inkscape are not compatible with my “HP7475A_feed_hpgl_file_01” sketch yet). InkScape also has the option to directly send graphics to the plotter, but I had no good experience with that. It also needs original HP Pens (or 3d printed adaptors), as it sends SP; commands, which let the plotter attempt to change the pen, before beginning to draw.

==='''How to install the HPGL library in Processing:'''===
Sketch → Import Library… → Add Library… → search for: HPGLGraphics → Install → restart Processing

You can now open the examples of the library (File → Examples → Contributed Libraries → HPGLGraphics → …). Try the examples and adapt the code for your own sketches.

==='''How to use the HPGLGraphics library in a Processing sketch?'''===

import hpglgraphics.*;
HPGLGraphics hpgl;

void setup(){
size(1104, 772); // 1616 x 1104 for A3(!?)
Hpgl = (HPGLGraphics) createGraphics(width, height, HPGLGraphics.HPGL);
hpgl.setPaperSize("A4"); //either A4 or A3
hpgl.setPath("yourFileName.hpgl"); //file will appear in sketch folder
noLoop();
}

void draw(){
beginRecord(hpgl);
// your code here (the graphics you want to export as hpgl file)
endRecord();
}

void mousePressed(){
redraw();
}

==='''How to send a HPGL file to the plotter?'''===
Use the “HP7475A_feed_hpgl_file_01” or “HP7475A_feed_hpgl_file_02” sketches, which are almost the same (only the buffer handling works differently). Both do not work perfect yet for each case, but almost. For very detailed graphics (for example the “noise.hpgl” file), version 02 works better. Instructions how to use the programs are in the comments

GMU:Algorithmic Art/HP 7475A

2018-11-19T13:51:00Z

Tobiaszimmer: /* How to use the HPGLGraphics library in a Processing sketch? */

=='''Working with the HP 7475A'''==
==='''General'''===
The plotter is placed in room 204, in the shelf behind the projection screen. Take it out, place it on a desk and connect the serial adapter to your computer. Please do not forget to return it to the shelf when you are done! You have to bring your own pens and paper. Expect that some trial and error is involved when working with the HP7475A, until you achieve perfect results.

==='''Working Times'''===
If you want to work with the plotter, first check if the room is currently unoccupied. If you want to be sure that no one else is working with the plotter, make sure to send a message to the whole class, with the date and time that you intend to use the plotter (Email, Telegram, WhatsApp!?) 
[https://www.uni-weimar.de/qisserver/rds?state=wplan&act=Raum&pool=Raum&show=plan&P.subc=plan&raum.rgid=2847 Class Schedule in M7 Room 204]

==='''Paper Setup'''===
The HP7475A either takes A4 or A3 paper. The thickness of the paper is very flexible.

==='''Pen Setup'''===
To use your own pens with the plotter, you can simply extend your pen’s diameter, by wrapping some paper around it. This way it will fit the pen mount of the plotter. A better way would be to 3D print adaptors, that exactly fit the original HP pen measurements. Unless you have a pen that mimmicks the original HP pen shape, avoid the HPGL commands SP; SP1; SP2; SP3; SP4; SP5; SP6; as they attempt to change the pen. 
[https://softsolder.com/2015/04/21/hp-7475a-plotter-oem-pen-body-model/ Original HP pen measurements and openSCAD code]

==='''Serial Connection'''===
You need to find out the COM port, as which the USB/Serial adaptor was registered in your computer. In Windows, you can find out in the Device Manager, in Mac OS, I don’t know yet.

==='''HPGL'''===
The plotter only understands HPGL (Hewlett Packard Graphics Language). You can try the “HP7475A_live_input” sketch, to test some HPGL commands. You can find documentation about that language here: 
[https://www.isoplotec.co.jp/HPGL/eHPGL.htm Simple but incomplete reference] 
[https://archive.org/details/HP7475AInterfacingandProgrammingManual Full original reference (PDF)] 
[https://archive.org/stream/HP7475AInterfacingandProgrammingManual/HP7475AInterfacingandProgrammingManual_djvu.txt Full original reference (txt)] 

Fortunately, there is a HPGL library for Processing, which can convert your sketches to HPGL files.

Another approach is to export a .svg file with Processing and to convert it to .hpgl with InkScape. (The files produced by inkscape are not compatible with my “HP7475A_feed_hpgl_file_01” sketch yet). InkScape also has the option to directly send graphics to the plotter, but I had no good experience with that. It also needs original HP Pens (or 3d printed adaptors), as it sends SP; commands, which let the plotter attempt to change the pen, before beginning to draw.

==='''How to install the HPGL library in Processing:'''===
Sketch → Import Library… → Add Library… → search for: HPGLGraphics → Install → restart Processing

You can now open the examples of the library (File → Examples → Contributed Libraries → HPGLGraphics → …). Try the examples and adapt the code for your own sketches.

==='''How to use the HPGLGraphics library in a Processing sketch?'''===

import hpglgraphics.*;
HPGLGraphics hpgl;

void setup(){
size(1104, 772); // 1616 x 1104 for A3(!?)
Hpgl = (HPGLGraphics) createGraphics(width, height, HPGLGraphics.HPGL);
hpgl.setPaperSize("A4"); //either A4 or A3
hpgl.setPath("yourFileName.hpgl"); //file will appear in sketch folder
noLoop();
}

void draw(){
beginRecord(hpgl);
// your code here (the graphics you wnat to export as hpgl file)
endRecord();
}

void mousePressed(){
redraw();
}

==='''How to send a HPGL file to the plotter?'''===
Use the “HP7475A_feed_hpgl_file_01” or “HP7475A_feed_hpgl_file_02” sketches, which are almost the same (only the buffer handling works differently). Both do not work perfect yet for each case, but almost. For very detailed graphics (for example the “noise.hpgl” file), version 02 works better. Instructions how to use the programs are in the comments