47da8dcbca
This patch puts threads that render the same pixel closer together, as opposed to threads that render the same sample. Thus threads within a warp are more coherent in memory access and control flow, leading to performance improvements. Example benchmarks on a Quadro RTX4000 (WDDM) on Windows 10: Koro: 4:23 -> 3:46 BMW: 1:18 -> 1:25 Barbershop Interior: 17:52 -> 14:55 Classroom: 4:37 -> 3:45 Performance differences on OpenCL/AMD were hit and miss, some scenes became faster, others lost significantly. Therefore, this is kept as CUDA only change for now.