> OK, so for anybody who knows about such things... Would it be feasible to 
> render an Iterated Function System image using a GPU? And would it be any 
> faster than using the CPU?

See attached image. That spike in the right CPU chart was where I started 
the program.

I'm using the standard fern algorithm that's on the wikipedia page about 
IFS.

Speed: 23.2 million iterations per second (512x512 points in parallel per 
frame at 88 fps)

This is on an nVidia FX1700, if I get time I'll try it on my FX7900 tonight, 
should be significantly faster.

I don't know how this compares to how fast a CPU would be, if I get time 
later I will try out the same on the CPU for comparison.

The hardest bit was actually getting a good random number generator inside 
the pixel shader.  What I ended up doing was to generate a big texture full 
of random numbers at the start of the code, then in the pixel shader it 
generates an xy coord based on a number of things and looks up the value in 
the random texture at that position.  Seems to work well, because believe 
me, if your random number generator is just a little bit wonky, the fern 
doesn't look very nice at all!

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