Incoherent ray tracing on GPU

Abstract

Tracing secondary rays, such as reflection, refraction and shadow rays, can often be the most costly step in a modern real-time ray tracer. In this paper, we propose a new approach to ray tracing on GPU. Our approach is especially efficient for incoherent rays. Combined with the common packets ray tracing, we propose a different data-parallel approach to ray tracing on GPU, in which individual ray intersect with k different nodes/triangles in the same operation. Besides, we add some additional information in the construction of acceleration structure, and propose a new approach to travel the acceleration structure. Our acceleration structure needn't collapse, so it could be built very efficiently, which is promising for dynamic scenes. Despite this approach is slower for primary rays, but demonstrate that it performs better than those techniques as soon as incoherent rays are considered. © 2010 ACADEMY PUBLISHER.