Excellent demo! I was looking at the code and wondering what sv was. It was worth running to the end.
Anyway, I run into the header issue when I tried to compile it with tcc. I alway compile you code and run using tcc.
I notice the diterh code is different this time and will try to figure it out.
I was thinking about making a fractal demo with your code...
Also, when I saw the speckle demo, I remember when I was going to school one of my classmates made a random dot stereogram http://en.wikipedia.org/wiki/Random_dot_stereogram