Parallel radiosity: Evaluation of parallel form factor calculations and a static load balancing algorithm

Abstract

Although the radiosity algorithm can generate photo-realistic images due to global illumination effects, a large amount of form factor calculations are required. This paper describes how to parallelize the radiosity algorithm by subdividing hemispheres into multiple elements and allocating them statically to multiple processors. An enhanced communication procedure is proposed, where partial hemisphere data at each processor is communicated and the complete hemisphere data prepared on all processors. In this procedure, the size of the communication data is independent of the number of elements. In addition, the load balancing efficiency of our static load balancing algorithm is evaluated. On the distributed memory parallel computer AP1000+ which has 64 processors, the speedup is 20.4 ~ 21.8 for benchmark scenes, and 35.0 ~ 40.2 for classroom scenes. The load balancing efficiency is 0.93 ~ 0.96.