Matrix Transforms for converting BumpNormals(World) to bumpNormals(Cam).

[sean_willis]

Hello!
I would like to save some disk space when rendering. I'm looking at eliminating some AOV outputs to make them procedurally generated from a known camera and pre-existing world pass.

Converting from World Normals to camera is trivial when said camera is orthographic and only needs the rotation matrix from the viewing camera's world orientation. But perspective cameras seem to be doing something differently.
Is there a known mapping that will convert between spaces in given an input camera and World P and N passes in Nuke? (We have VRay for Nuke too)

If not I'll need to jump down the homogeneous clip coordinates rabbit hole to rebuild the internal perspective projection mapping.

I have already eliminated the facing ratio "Fresnel" pass by using the world normals.

Thanks for reading,
-Sean