Interactive Particle Visualization Using Advanced Illumination Models

by
Christiaan Paul Gribble

Advised by
Steve Parker

Particle methods are commonly used to simulate complex phenomena in many scientific domains. Thousands or even millions of particles are required to model a system accurately, resulting in very large, very complex datasets. Effective visualization of this data requires communicating subtle changes in three-dimensional structure as the simulation evolves, as well as allowing easier navigation and exploration of the data through interactivity. Typical interactive visualization systems employ only local illumination models to render these datasets. We submit that advanced illumination models, such as ambient occlusion and global illumination, can help viewers understand complex spatial relationships and three-dimensional structure. The method we describe overcomes the computational limitations of these models by removing the illumination calculation from the interactive rendering pipeline using a preprocessing phase. In the our method, the illumination across each particle is sampled and compressed in a manageable set of textures. These textures are then mapped to the particles during interactive rendering. We show that this approach enables interactive visualization of large particle datasets with global illumination cues such as indirect illumination.