3D Texture Mapping in hardware

Hi,

I know how to make use of “glTexImage3D” and the texture matrix to implement volume rendering. I draw a bunch of quads back-to-front and assign texture coordinates to them. Now I apply all my modeling transformation to the Texture matrix stack (not modelview matrix stack). This gives me the volume rendering effect.

Now I want to know how it is implmented behind the OpenGL’s magic curtain (API) ?

Any reference dcumentation, online links would be appreciated. Thank you!

Everything you need to know should be in the spec. Download and read the OpenGL 2.0 spec or earlier (don’t think it has changed for glTexImage3D since 1.1 or 1.2 if at all). The spec is used by hardware companies (and some software like MESA) to implement OpenGL. Tells you everything you need to know though each company/organization probably has different implementations with same/similar results.