Accelerating spatial data structures in ray tracing through precomputed line space visibility

Abstract

We propose an efficient approach to precompute and reuse visibility information based on existing spatial data structures by using a precomputed data structure: the line space. This data structure provides an additional skip condition by checking whether the subnodes in a hierarchical spatial data structures need to check for intersection with the ray. We evaluate this method on different test scenes and show that it is able to achieve a remarkable speed-up by using this skip condition. Furthermore we describe algorithms for fast set-up and traversal in detail and discuss important strategies for this approach.