Stochastic Ray Tracing Using SIMD Processor Arrays

Abstract

Stochastic ray tracing is one of the most elegant methods for anti-aliasing and for generating such phenomena as soft shadows, fuzzy reflections, depth of field, and motion blur, which are difficult to accomplish with the conventional ray-tracing algorithm. Unfortunately, it makes use of stochastic sampling, which requires more than one sample for each pixel. One possible way to speed up ray tracing is to explore the inherent parallelism of the algorithm. In the past few years, the major focus of parallel ray-tracing research has been on the use of MIMD architectures. Although SIMD architectures may be ideal for ray tracing simple scenes, they have been thought unsuitable for ray tracing complex scenes. However, by using scene coherence, we have found that stochastic ray tracing using SIMD processor arrays can be as efficient as most of the existing MIMD ray-tracing algorithms and more cost effective.