Below are several Reaction Diffusion System apps which help to understand the parameters at play on the famous algorithm developed by Alan Turing (1912-1954).
The first one is programmed in Java: http://cgjennings.ca/toybox/turingmorph/
The source code is available for you to tweak in a java app, you can use the Eclipse IDE (integrated development environment) to program in Java and test the results: http://cgjennings.ca/toybox/turingmorph/TuringMorph.java
The second one is programmed using Processing which is a language based on Java: http://www.openprocessing.org/sketch/15905
To download and try Processing go to Processing.org you can download the interface for free and access the forum for help.
A 3D processing app and pavillion design was done by BioThing (Alisa Andrasek and Jose Sanchez) based on the same Turing patterns: http://www.biothing.org/?p=449 Biothing also held a workshop with the DRL studio based on 3D reaction diffusion patterns: