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GhostAce

Vertex program texture fetch

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Hi, I have GeForce FX6600 PCIE. I have written a simple vertex shader that fetches height value from heightmap and translates vertex by that value along it's normal. My problem is that it's terribly slow. I get 20 fps with just a few vertices (25 actually). I've tried different texture sizes and installed latest drivers but fps stays the same. Is such low fps normal for FX6600, and what can I do to improve it? What gfx card is able to fetch texture in vertex programs in a reasonable speed? thx

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What sort of texture are you using?



GeForce 6 cards only support vertex textures in hardware for textures that are single 32 bit float or 4 channel (RGBA) 32 bit floats. i.e.:



GL_LUMINANCE_FLOAT32_ATI and GL_RGBA_FLOAT32_ATI for OpenGL.



D3DFMT_R32F and D3DFMT_A32B32G32R32F for D3D.



See Using Vertex Textures



If you are not using one of those formats, it is probably dropping back to software rendering.



dave j

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Quote:
Original post by dave j
What sort of texture are you using?
GeForce 6 cards only support vertex textures in hardware for textures that are single 32 bit float or 4 channel (RGBA) 32 bit floats. i.e.:
GL_LUMINANCE_FLOAT32_ATI and GL_RGBA_FLOAT32_ATI for OpenGL.
D3DFMT_R32F and D3DFMT_A32B32G32R32F for D3D.
See Using Vertex Textures
If you are not using one of those formats, it is probably dropping back to software rendering.
dave j


What?! Why? That's about as ridiculous as not having pre-PS stencil testing!


Edit: That's weird, two < br>'s were added for each new line...

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