Last month, I gave a 1 day workshop @ STEREOLUX (Nantes - 44 - France) about 3D rendering, with advanced buffer techniques.
This knowledge was learned in my past experience, about 10 years in Animation Movies Industry ; we use a lot these render passes to tweak the 3d renders and get the final result.
Here is the Toe file.
On the left : Geometry import / scene setup and 3D render to get buffers
On the center : B2BK custom tools (FastMAT, FastENV, NormMask, PosMask, UVPaint & UVPict)
On the right : One example of the use of these tools, to make the teaser image
Don't hesitate to contact me for further information and/or help.
Bertrand de BECQUE [B2BK]