It's tweaked for my PIII-700 where I get 50 FPS. It could probably be made
many times faster however by optimizing specifically for power-of-2 grid sizes
(especially the FFT computation). Right mouse click pops up a menu.
The particular screen-shot above shows a swirling texture with vorticity
visualization enabled, where vorticity is simply the curl of the velocity
field. Clockwise circulation is represented by red and counterclockwise by
blue. This was made on a 100x100 grid with a 512x512 texture, although the
demo uses a hard-coded 64x64 grid with very low resolution textures. A couple
of even higher quality screen-shots can be found here:
http://matrix.netsoc.tcd.ie/~the_one/wallpaper_scifi.jpg
and here: http://matrix.netsoc.tcd.ie/~the_one/wallpaper_paint.jpg
If anyone has any questions to post, I'll be happy to answer them...