Processing Wiki

Physics Libraries

Tue, 09 Feb 2010 17:07:47 GMT

http://www.cs.princeton.edu/~traer/physics/
And here's an example of it being used for a cloth sim:
http://www.jrc313.com/processing/cloth/

code.google.com, "toxilibs":
http://code.google.com/p/toxiclibs/

MSAFluid
http://memo.tv/msafluid_for_processing
http://memo.tv/files/memotv/msafluid_for_processing/index.html

PPHys2D
http://pphys2d.jmcouillard.com/

Daniel Shiffman has been working on integrating Box2d into Processing:
http://www.box2d.org/
http://www.shiffman.net/teaching/nature/box2d-processing/
http://code.google.com/p/pbox2d/

Processing Links

Thu, 10 Dec 2009 16:45:00 GMT

Official:

Java-specific: (Processing is built on Java)
Official:

The Java Tutorials
- Sun's Java page on OOP
New to Java Programming Center
Java 2 Platform, Standard Edition, v 1.4.2 API Specification (Java classes for use in Processing)

Other:

Beginning Java : online tutorial recommended to me at joegrip.com.

Inspiration:

External Code \ Libraries:

IDE's:

Eclipse : See a tutorial for getting Processing working in Eclipse here.
Obsessing : Author Processing in your browser.
Lily Processing : Visual programming in Processing.

Informative:

Wikipedia
http://whatfettle.com/2008/05/TiddlyProcessing/ & http://tiddlyprocessing-simon.tiddlyspot.com/
- Sites with the ProcessingjsPlugin, allowing for Processing execution in tiddywiki's.

Recomended Books:
Processing Specific:

Processing: A Progamming Handbook for Visual Designers and Artists
- Downloads for this book can be found here
Processing: Creative Coding and Computational Art
- Can download the lessons and example chapters there too.
Learning Processing
- Can download lessons and examples there too.

Java Specific:

The Java Tutorials: A Short Course on the Basics 4th Edition : Based on the tutorials from Suns official site.
Thinking in Java Fourth edition. I was recommended this.
- Thinking in Java Third edition, free online book (but, published in 2002, so I'm not sure how current it is).
Head First Java 2nd Edition. I was recommended this.
On to Java 3rd Edition. I was recommended this.

Similar to Processing:

How can I read data from the web?

Tue, 08 Dec 2009 17:33:00 GMT

The easiest way is with loadStrings
Modified version from the docs, read in a playlist file from the web:

String lines[] = loadStrings("http://somafm.com/groovesalad.pls");
for (int i=0; i < lines.length; i++) {
  println(lines[i]);
}

Prints:

[playlist]
numberofentries=4
File1=http://streamer-ntc-aa02.somafm.com:80/stream/1018
Title1=SomaFM: Groove Salad (#1 128k mp3): A nicely chilled plate of ambient beats and grooves.
Length1=-1
File2=http://streamer-mtc-aa04.somafm.com:80/stream/1018
Title2=SomaFM: Groove Salad (#2 128k mp3): A nicely chilled plate of ambient beats and grooves.
Length2=-1
File3=http://streamer-ntc-aa04.somafm.com:80/stream/1018
Title3=SomaFM: Groove Salad (#3 128k mp3): A nicely chilled plate of ambient beats and grooves.
Length3=-1
File4=http://ice.somafm.com/groovesalad
Title4=SomaFM: Groove Salad (Firewall-friendly 128k mp3) A nicely chilled plate of ambient beats and grooves.
Length4=-1
Version=2

How can I get a list of files from a directory?

Tue, 08 Dec 2009 17:32:00 GMT

Example found in Processing Hacks by 'antiplastik':
http://processing.org/hacks/doku.php?id=hacks:listing-files
Source:

/**
listing-files taken from http://processinghacks.com/hacks:listing-files
@author antiplastik
*/
 
// we'll have a look in the data folder
java.io.File folder = new java.io.File(dataPath(""));
 
// let's set a filter (which returns true if file's extension is .jpg)
java.io.FilenameFilter jpgFilter = new java.io.FilenameFilter() {
  boolean accept(File dir, String name) {
    return name.toLowerCase().endsWith(".jpg");
  }
};
 
// list the files in the data folder, passing the filter as parameter
String[] filenames = folder.list(jpgFilter);
 
// get and display the number of jpg files
println(filenames.length + " jpg files in specified directory");
 
// display the filenames
for (int i = 0; i < filenames.length; i++) println(filenames[i]);

SideBarTabs

Fri, 28 Aug 2009 16:13:00 GMT

WarpCat

Thu, 27 Aug 2009 20:48:00 GMT

Yes, that is me playing Rock Band.
Eric Pavey

Email: - warpcat (at) sbcglobal (dot) net -
Blog - LinkedIn - Flickr - Youtube - MobyGames - RSWarrior

My other Tiddlywiki's:

2009 09 09

Mon, 10 Aug 2009 01:27:00 GMT

On a bit of a hiatus. Basically, I've been learning game authoring in Python via PyGame, and that has taken up most of my brainpower. I'm sure I'll get back to Processing dev at some point.

Blog

Mon, 10 Aug 2009 01:27:00 GMT

The Processing Wiki blog

2009 09 09 - On a break...
2009 04 14 - Added the JAVA & OPENGL Category.
2009 01 12 - Added EXT REFERENCE Category.
2008 06 11 - TiddlyProcessing!
2008 06 10 - Processing tiddlywiki is born!

About Processing Wiki

Thu, 14 May 2009 15:51:00 GMT

These are my online notes while I learn Processing. What is Processing? From the site:

Processing is an open source programming language and environment for people who want to program images, animation, and interactions. It is used by students, artists, designers, researchers, and hobbyists for learning, prototyping, and production. It is created to teach fundamentals of computer programming within a visual context and to serve as a software sketchbook and professional production tool. Processing is an alternative to proprietary software tools in the same domain.

To add to that, Processing is a higher level wrapper around the programming language Java, similar in the way PyGame wrappers Python. The advantage is, while Processing gives you a lot of power, you can still directly access the underlying language as well.

DISCLAIMER

I can't be blamed for anything misrepresented on this page! If it doesn't work, no finger-waving my direction.
If you find something wrong, please tell me. I am trying to correctly learn this stuff.
Since I work on a Windows system, the majority of the command line stuff I call out to is Win-centric. If you're using Lunix\Unix\OSX etc, I can't comment on how well things will work.

MSAFluid

Tue, 12 May 2009 19:57:00 GMT

"This is a library for solving real-time fluid dynamics simulations based on Navier-Stokes equations and Jos Stam's paper on Real-Time Fluid Dynamics for Games. While I wrote the library primarily for processing it has no dependency on processing libraries and the source can be used with any Java application. "
http://memo.tv/msafluid_for_processing
http://memo.tv/files/memotv/msafluid_for_processing/index.html

How can I have a key press trigger an event?

Thu, 23 Apr 2009 03:53:00 GMT

While a sketch is running you can author a function around the keyPressed system variable, that queries which key is pressed, via the key system variable:

void keyPressed()
{
// Note the single quotes ('), not double quotes(")
  if(key == 'a') {
    // do something
  }
}

3D coordinate space

Fri, 17 Apr 2009 04:55:00 GMT

Based on a 2d sketch, x0 & y0 are in the top left corner of the image, with +x (width) going 'right', and +y (height) going 'down'.

In a 3d sketch (using OPENGL or P3D), depth is introduced. X & Y remain the same, but depth, Z is added, also starting at the 'top left corner' with a value of 0. By default, +z comes 'out' of the screen, while -z goes into the screen.

Honestly, this system seems completely backwards to me, coming from DCC software like Maya. In that software, '0' would be the 'origin', with +x going 'left', +y going 'up', +z going 'forward' (thus the term 'z depth'). Perfectly visualized by holding up your right hand, with thumb going left, pointer going up (like making a backwards 'L'), and middle finger going forward.

width and height are constants you can query in your sketch. I often will make one called depth at the root of the sketch, and either update it there, or in the setup() function.

GLGraphics

Wed, 15 Apr 2009 05:27:00 GMT

http://users.design.ucla.edu/~acolubri/processing/glgraphics/home/
"GLGraphics is a library for the Processing programming language that integrates OpenGL textures and GPU-accelerated effects into the Processing API. "

Tread on bugs with Processing v1+:
http://processing.org/discourse/yabb2/YaBB.pl?num=1237493983

OpenGL

Wed, 15 Apr 2009 05:27:00 GMT

Some notes....

Thread:
http://processing.org/discourse/yabb2/YaBB.pl?num=1210936403/6#6
From that thread by sgsrules:

import processing.opengl.*;  
import javax.media.opengl.*; // This is the jogl library you need

PGraphicsOpenGL pgl; // from processing.opengl.*
GL gl;  // from javax.media.opengl.*

void setup(){
  size(600,600,OPENGL);
  hint( ENABLE_OPENGL_4X_SMOOTH); // anti aliasing

  pgl = (PGraphicsOpenGL) g;
  gl = pgl.gl;
}

void draw(){
  background(0);
  // processing code goes here

  pgl.beginGL(); // place before you native gl code
  // gl code does here

  // this translates the different matrices and other stuff so that  
  // you can use gl commands note that most of the processing commands will
  // not work or will behave strangly so don't mix the two.  Gl geometry
  //  will only be lit with gl lights and normals.
  pgl.endGL(); //place after your native gl code, you can place more processing stuff here
}

Docs on /PGraphicsOpenGL
http://dev.processing.org/reference/everything/javadoc/processing/opengl/PGraphicsOpenGL.html

OpenGL blending
From Flight 404:
http://www.flight404.com/blog/?p=71
http://www.flight404.com/blog/?p=72

Processing.org thread:
http://processing.org/discourse/yabb2/YaBB.pl?num=1207671111
Sample sketch:
http://boxofbooze.com/processing/glblend.html
glBlendFunc
http://pyopengl.sourceforge.net/documentation/manual/glBlendFunc.3G.html

More additive blending stuff:
http://processing.org/discourse/yabb2/YaBB.pl?num=1226360818
from pelintra

import processing.opengl.*;
import javax.media.opengl.GL;

PGraphicsOpenGL pgl;
GL gl;

void setup(){
//just put what you would normally put here
}

void draw(){
//here you just add this code:
pgl = (PGraphicsOpenGL)g;
gl = pgl.beginGL(); //getting the GL object used by processing
gl.glEnable(GL.GL_BLEND);  // enabling blend
gl.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE); //defining additive blend
pgl.endGL();

//now everything you draw will be drawn using additive blend
//making glows more glowy! 
}

What types of variables does Processing have?

Wed, 15 Apr 2009 05:24:00 GMT

Variables:

boolean : true or false. 1 or 0
byte : The byte representation of an int, or char, from -128 to 127.
char : A numeric representation for a single character
float : A floating point value.
double : A datatype for floating-point numbers larger than those that can be stored in a float.
int : Number with no decimal.
long : Datatype for large integers (bigger than int if you need it).
color : Datatype for storing color values.

More advanced variables, or classes that act like variables:

String : A sequence of text. It's capitalized (because it's a class), has associated methods.
PFont : Font data type, filled by loadFont, and setup with textFont. See my notes here: Text and fonts
PImage : Image data type, filled by loadImage, and setup with image. Has methods
PVector : New to Processing 1.0.
Array : Most variables can be made into an array, see Info on arrays
ArrayList : A dynamically resizable Array
HashMap : Also known as 'dictionaries' in other languages, it stores a collection of objects, each referenced by a key.
Any Object made by a class has it's own variable type.

There are a few more obscure ones. Check the Processing Extended Reference under 'Data'.

2009 04 14

Wed, 15 Apr 2009 04:05:00 GMT

Added the JAVA category. Since Processing is based on Java, any Java language specific stuff I'll add here.
Added the OPENGL category. I'm learning more about it... so might as well make a section.

Depth of field

Wed, 15 Apr 2009 04:04:00 GMT

Notes and whatnot...

http://screamyguy.net/DepthOfField/index.htm
http://screamyguy.net/dandelion/index.htm

MainMenu

Wed, 15 Apr 2009 04:04:00 GMT

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Comparable

Wed, 15 Apr 2009 04:01:00 GMT

I often see classes in Processing that implement 'Comparable':

class MyObj implements Comparable {
  // stuff...
}

Official notes on the Java object:
http://java.sun.com/j2se/1.4.2/docs/api/java/lang/Comparable.html
Notes from the doc:

This interface imposes a total ordering on the objects of each class that implements it. This ordering is referred to as the class's natural ordering, and the class's compareTo method is referred to as its natural comparison method.

Lists (and arrays) of objects that implement this interface can be sorted automatically by Collections.sort (and Arrays.sort). Objects that implement this interface can be used as keys in a sorted map or elements in a sorted set, without the need to specify a comparator.

Notes from Processing hacks:
http://processing.org/hacks/hacks:comparable

sprites

Wed, 08 Apr 2009 05:40:00 GMT

Some links dealing with the code behind having sprites face a camera:
http://processing.org/discourse/yabb2/YaBB.pl?num=1212648257
http://nehe.gamedev.net/data/articles/article.asp?article=19
Example sketch online:
http://www.seltar.org/projects/particle3D/v2/