scott wrote:

> Yes, and yes it would be much faster.  Sometimes you need to think a bit 
> before implementing such a thing though...
> 
> I would run several points through the IFS in parallel.  Say, 2^16 
> points. Create two 256x256 textures of floats, one to hold the X 
> coordinates and one to hold the Y coordinates of all your points.
> 
> Then write two pixel shaders, one to calculate the new X coordinate, and 
> one to create the new Y coordinate.
> 
> Then, for each pass, set the current X and Y textures and inputs, and 
> render to the newX texture.  Render again to the newY texture with the 
> other pixel shader.
> 
> Now, here comes the clever bit.  After you've generated the new XY 
> textures, you now run a *vertex* shader with 2^16 quads.  THe vertex 
> shader looks up the XY values from the texture for each quad and 
> translates the quad to that position.  You can then just use a fairly 
> normal pixel shader to increment the pixel value on the screen, or some 
> off-screen texture.
> 
> It should run pretty fast, and don't forget you're doing 64k points in 
> parallel so it should outrun the CPU by a huge factor.

Uuhhh... any chance of some code? :-}

(Also... what's a vertex shader?)

Would it be possible to do all this using just, say, OpenGL? So far the 
approaches I've considered would all require CUDA, which obviously works 
*only* for certain GPUs.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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