Not even a book?
Your best bet is sifting through the source of some old school demo. Might not be the best structured code but gives ideas about clipping etc. The best of class parallel rendering systems that rival or give hardware renderers a good fight is the half-space, grid or tile-based (threaded), a la Nick Capens pixel drawers (don't know what to call them really as they don't do scan line rasterisation, really a bastard version of ray casting). I think his system was bought up by some VCs and later commercialised?
PS - (speculative) His web history has been wiped clean not to give too many hints about the tech behind. I guess due to the patenting or other issues.
PS2 - I might be right after all :-) http://transgaming.com/swiftshader
Edited by spinningcube, Today, 11:20 AM.