Performance Comparison of Bounding Volume Hierarchies and Kd‐Trees for GPU Ray Tracing

We present a performance comparison of bounding volume hierarchies and kd-trees for ray tracing on many-core architectures (GPUs). The comparison is focused on rendering times and traversal characteristics on the GPU using data structures that were optimized for very high performance of tracing rays. To achieve low rendering times, we extensively examine the constants used in termination criteria for the two data structures. We show that for a contemporary GPU architecture (NVIDIA Kepler) bounding volume hierarchies have higher ray tracing performance than kd-trees for simple and moderately complex scenes. On the other hand, kd-trees have higher performance for complex scenes, in particular for those with high depth complexity. Finally, we analyse the causes of the performance discrepancies using the profiling characteristics of the ray tracing kernels.