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View Full Version : how make bump mapping with open gl ?



airseb
09-22-2003, 08:27 AM
with what open gl functions i can do it ?
thanks.

jwatte
09-22-2003, 08:37 AM
You have the texture matrix per texture unit.

You have the DOT3 function for the TexEnv.

Easiest is to put object space normal map into a texture, light direction into a texture environment color, and set the combine function to DOT3. Then modulate with diffuse color in the next stage.

Also, with ARB_fragment_program, you just write whatever bump sampling and per-pixel lighting function you want, so there the API doesn't get in the way at all; it's all up to you.

V-man
09-22-2003, 08:40 AM
There are many ways (tex_combiner, reg_combiner, ...) but it basically involves a DOT product calculation per fragment.

Why not download a demo from ati or nvidia?

airseb
09-22-2003, 08:42 AM
ok thanks guys ! i'll study your proposals :-)