Anti-aliased Hemicubes for Performance Improvements in Radiosity Solutions

Abstract

Several important and fascinating aspects of realistic images are captured by the radiosity method. In this paper we use an alternate form of the classical hemicube that reduces aliasing problems inherent in the original method without giving up the computational advantages of the hemicube. Unlike other methods, we explicitly consider the e ect of the relative order of partial visibility in a hemicube cell when recording form factors. This enables us to compute form factors accurately (even) in progressive re nement radiosity with adaptive substructuring. Our empirical results with progressive re nement radiosity show superior mesh density where ne details are required, (such as in soft shadows), as well as in areas that produce singularities (such as when inter element distances tend to zero). Our method is contrasted with hierarchical radiosity which uses raycasting for form factor and visibility computations. On a low end Intel Linux platform, and for a comparable image quality, our method takes substantially less time.