Efficient Hardware Acceleration of Robust Volumetric Light Transport Simulation

Abstract Efficiently simulating the full range of light effects in arbitrary input scenes that contain participating media is a difficult task. Unified points, beams and paths (UPBP) an algorithm capable capturing wide effects, by combining bidirectional path tracing (BPT) photon density estimation (PDE) with multiple importance sampling (MIS). A computationally expensive task UPBP MIS weight computation, performed each time formed. We derive efficient to compute weights for UPBP, which improves over previous work eliminating need iterate vertices. achieve this maintaining recursive quantities as subpaths are generated, from subpath can be computed. In way, computed only using data cached at two vertices ends subpaths. Furthermore, costly part PDE search nearby points beams. Previous has shown spatial structure mapping implemented hardware‐accelerated bounding volume hierarchy NVIDIA's RTX GPUs. show same technique applied different types volumetric compare performance these structures state art. Finally, our new we fully implement on GPU we, best knowledge, first do so.