> 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.

OK so my FX7900 wasn't that much faster (37 million per second), despite the 
specs indicating about 5x the pixel throughput.  The speed bottleneck is 
obviously somewhere else in this code then, probably in the texture lookup 
in the vertex shader, I guess that isn't very optimised yet.  If I had a 
DX10 card I could use a geometry shader to cut the number of texture lookups 
and vertex shader calls by a factor of 4, that would definitely speed things 
up significantly.

> 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.

Using a single core of an Intel E6400 I get 11 million iterations per second 
(C++, but with no graphics).

Also it took me like 5 minutes to write the CPU code from scratch, but 
several hours to get the GPU code working correctly!

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