Is it after the modelview transform (eye-space) and before the projection transform? Or is it after both the modelview and projection transformations (clip-space)?
I ask because I've created my own implementation of the OpenGL lighting model in clip-space and I am not always getting identical results versus my reference ATI implementation. I would like to know whether some of these bugs are because I'm in the wrong coordinate-space .
My hope is that it can be performed in clip-space, so that I can perform primitive assembly and trivial clipping rejection first such that I only calculate the lighting at vertices belonging to primitives visible on the screen.
Thanks,
-Toasty
I ask because I've created my own implementation of the OpenGL lighting model in clip-space and I am not always getting identical results versus my reference ATI implementation. I would like to know whether some of these bugs are because I'm in the wrong coordinate-space .
My hope is that it can be performed in clip-space, so that I can perform primitive assembly and trivial clipping rejection first such that I only calculate the lighting at vertices belonging to primitives visible on the screen.
Thanks,
-Toasty