Cost prediction for ray shooting in octrees

The ray shooting problem arises in many different contexts and is a bottleneck of ray tracing in computer graphics. Unfortunately, theoretical solutions to the problem are not very practical, while practical methods offer few provable guarantees on performance. Attempting to combine practicality with theoretical soundness, we show how to provably measure the average performance of any ray-shooting method based on traversing a bounded-degree spatial decomposition, where the average is taken to mean the expectation over a uniform ray distribution. An approximation yields a simple, easy-to-compute cost predictor that estimates the average performance of ray shooting without running the actual algorithm. We experimentally show that this predictor provides an accurate estimate of the efficiency of executing ray-shooting queries in octree-induced decompositions, irrespective of whether or not the bounded-degree requirement is enforced, and of the criteria used to construct the octrees. We s...

• Type: Journal
• Year: 2006
• Where: COMGEO
• Authors: Boris Aronov, Hervé Brönnimann, Allen Y. Chang, Yi-Jen Chiang
• Keywords: Applied Computing, Average Performance, COMGEO 2006, NSF CAREER Grant, Ray Distributions