Hey,
I’m new to developing Mental Ray shaders and have been looking for a way to implement Precomputed Radiance Transfer/Spherical Harmonic lighting inside of Mental Ray & Maya.
It’s very similar to lightmapping. I basically need to be able to sample the hemisphere around each vertex, and project that onto the SH functions, and then export the co-efficients back into Maya as per vertex custom attributes.
I’m stuck at the part on how/where to extend Mental Ray so that I can run this sampling function. The other parts I have figured out.
I’ve scoured the Maya documentation but I can’t seem to make any headway (especially about the part in returning data back from mental ray)