yep :) Pre-render steps (building the BVH/KDTree, caching transformed geometry, caching textures and building mipmaps) can take 2 hours before the rendering ev

yep :) Pre-render steps (building the BVH/KDTree, caching transformed geometry, caching textures and building mipmaps) can take 2 hours before the rendering even starts :) And this is on a machine with 32 i7 cores and 96 GB of RAM. There's a reason SPI and Weta (and the other CG/VFX companies, although those two have the biggest) have huge renderfarms...