Wow, the cross-fades really sell it. I never even tried to do anything like that; my genetic programs were for a kind-of-weird stack machine as the easiest thing to do. https://github.com/darius/tusdl/blob/master/evo.c

Slightly related to the starting topic of learned exploits: op_hwb_color() producing most of the colors seems to have suffered from some undefined or implementation-defined behavior -- I couldn't reproduce old pictures when I came back to this many years later. Yet that one misbehavior deserves a lot of the credit for whatever aesthetic value turned up. C'est encore la vie.