I recently needed to create some patterns to use in a series of logos. We wanted the logos to be based on a generative pattern so we could create as many as we wanted to, with a large amount of variation. I thought about using Processing but wasn't sure how useful the vector output would be. I'd still like to know. But I thought I might need a high quality vector graphic to send to print as well as web, so I thought it would be a good opportunity to try scripting Adobe Illustrator.
The whole Adobe Creative Suite has the ability to be scripted, using either JavaScript, AppleScript or VBScript. The applications use an object model which should be easy to pick up for anyone familiar with web browsers' Document Object Model, and there is extensive documentation available on Adobe's website. So, writing JavaScript gives you extensive access to Illustrator's features, and it's quite quick too. There are some incomprehensible shortcomings, some of which I detail in the code's comments, but as a first experiment at trying this I think it went quite well.
Example output here: http://paulcarvill.github.com/GenerativePatternsWithIllustrator/
You'll see from the code that I was learning as I went, hence the proliferation of CONSTANTS I created every time I came up with a new setting which needed to be configured.
Have a play and let me know what you think.
This is for Illustrator as found in Adobe Creative Suite 5 (version 15.1.0). It probably won't work in earlier versions.