Why?? Well, our group uses Blender quite a bit, and Blender uses Python as its scripting language. More generally, Python is quite popular within our scientific community.

Jython, a Python implementation using the JVM, has been surprisingly successful, having most of what we like about CPython. And its Java integration made it a natural for Processing. This presentation is a good overview.

Processing is more than a graphics library, it has a delightful IDE which makes Java much easier, especially for the Java novice. The IDE has great tools such as a web-page builder with the project as an applet. It also can build an application version for Mac, Windows and Linux.

One difficulty we faced however, was that we wanted to commit to fairly complicated models that would benefit from Java 1.5 (Processing uses an earlier version) and an IDE familiar to Java programmers. We also are interested in interfacing Java to other languages such as Groovy, Python/Jython, Ruby/JRuby, and even JavaScript/Rhino.

So I decided to experiment with Processing, using Eclipse and Java 1.5. To do this, I made two models: RandBoxes, which is really simple .. just showing 1000 boxes and randomly jiggling them each step. The second model, RoadGrid, is more complicated: it draws a rectangular road grid and has “cars” (rectangles) moving along the roads. At each intersection, the cars randomly chose a new road segment.