GPU Accelerated Tandem Traversal of Blocked Bounding Volume Hierarchy Collision Detection for Multibody Dynamics

Abstract

The performance bottleneck of physics based animation is often the collision detection. It is well known by practitioners that the collision detection may consume more than half of the simulation time. In this work, we will introduce a novel approach for collision detection using bounding volume hierarchies. Our approach makes it possible to perform non-convex object versus non-convex object collision on the GPU, using tandem traversals of bounding volume hierarchies. Prior work only supports single traversals on GPUs. We introduce a blocked hierarchy data structure, using imaginary nodes and a simultaneous descend in the tandem traversal. The data structure design and traversal are highly specialized for exploiting the parallel threads in the NVIDIA GPUs. As proof-of-concept we demonstrate a GPU implementation for a multibody dynamics simulation, showing an approximate speedup factor of up to 8 compared to a CPU implementation.