Shaft Culling for Efficient Ray-Cast Radiosity
In radiosity algorithms, much time is spent computing visibility between two surfaces. One approach to approximating this visibility is to use ray casting methods. A new algorithm is presented which takes advantage of object coherency when using ray casting for radiosity. An efficient method is presented to form a volume between the emitter and receiver, and then generate a candidate list of items partially or wholly within the volume. Using this list, ray casting is performed to determine the amount of visibility between surfaces. Statistics are presented showing the decrease in overall computation time compared to a traditional ray casting technique.
KeywordsCandidate List Reference Item Bound Volume Hierarchy IEEE Computer Graphic Light Buffer
Unable to display preview. Download preview PDF.
- Arvo, J. (1990) in: Glassner, A.S. (ed) Graphics Gems, Academic Press, London, 335–339, “A Simple Method for Box-Sphere Intersection Testing.”Google Scholar
- Marks, J., Walsh, R., Christensen, J. & Friedell, M. (1990) Proceedings of Graphics Interface’ 90, Canadian Information Processing Society, Toronto, Ontario, 17–30, “Image and Intervisibility Coherence in Rendering.”Google Scholar
- Salesin, D. & Stolfi, J. (1989) Proceedings of the PLXIM’ 89 Conference, Hermes Editions, Paris, France, 451–466, “The ZZ-Buffer: a Simple and Efficient Rendering Algorithm with Reliable Antialiasing.”Google Scholar