HLBVH: Hierarchical LBVH Construction for Real-Time Ray Tracing
"HLBVH: Hierarchical LBVH Construction for Real-Time Ray Tracing"
Jacopo Pantaleoni (NVIDIA), David Luebke (NVIDIA), in High Performance Graphics 2010, June 2010
|Research Area:||Ray Tracing|
|Author(s):||Jacopo Pantaleoni (NVIDIA), David Luebke (NVIDIA)|
We present HLBVH and SAH-optimized HLBVH, two high performance BVH construction algorithms targeting real-time ray tracing of dynamic geometry. HLBVH provides a novel hierarchical formulation of the LBVH algorithm [Lauterbach et al 2009] and SAH-optimized HLBVH uses a new combination of HLBVH and the greedy surface area heuristic algorithm. These algorithms minimize work and memory bandwidth usage by extracting and exploiting coarse-grained spatial coherence already available in the input meshes. As such, they are well-suited for sorting dynamic geometry, in which the mesh to be sorted at a given time step can be defined as a transformation of a mesh that has been already sorted at the previous time step. Our algorithms always perform full resorting, unlike previous approaches based on refitting. As a result they remain efficient even during chaotic and discontinuous transformations, such as fracture or explosion.