Zoet,T., Bikker,J.
Abstract:
In ray tracing, a large fraction of rendering time consists of traversal of the acceleration structure. Most methods that aim to accelerate this process do so by skipping nodes high in the tree. We propose offsetting ray origins just before starting traversal. This allows rays to be moved out of nodes deep in the tree, avoiding the scattered, cache-unfriendly memory access associated with these rarely visited nodes. We do this using a precomputed set of hemispheres placed on the geometry surface which are guaranteed not to contain any geometry, thus allowing rays starting inside a hemisphere to be moved to the hemisphere"s boundary.