I did a little research. The original author just wrote a normal perl script, then used a module that obfuscates in a special way to create the pictures.
The original perl was (I believe) this:
They site has a whitespace implementation as well, but I didn't think cutting-n-pasting it here would really do any good.
There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors