Environment Mapping for Efficient Sampling of the Diffuse Interreflection
Environment mapping is a technique to compute specular reflections for a glossy object. Originally proposed as a cheap alternative for ray tracing, the method is well suited to be incorporated in a hybrid rendering algorithm. In this paper environment mapping is introduced to reduce the amount of computations involved in tracing secondary rays. During rendering, instead of tracing the secondary rays all through the scene, values are taken from the maps for the rays that would otherwise hit distant objects. This way the quality of the image is retained while providing a cheap alternative to stochastic brute force sampling methods. An additional advantage is that due to the local representation of the entire 3D scene in a map, parallelising this algorithm should result in a good speed-up and high efficiency.
KeywordsCoherence Lution Indigo Aliasing
Unable to display preview. Download preview PDF.
- Greene, N.: Environment mapping and other applications of world projections, IEEE Computer Graphics and Applications (1986) 21–29.Google Scholar
- Hall, H.: Hybrid Techniques for Rapid Image Synthesis, course notes, SIGGRAPH ’86: Image Rendering Tricks, (1986).Google Scholar
- Kok, A. J. F., Jansen, F. W.: Source selection for the direct lighting computation in global illumination, in Proceedings Eurographics Workshop on Rendering, Barcelona, Spain (1991).Google Scholar
- Kok, A. J. F.: Grouping of patches in progressive radiosity, in M. Cohen, C. Puech, F. Sillion, eds, Fourth Eurographics Workshop on Rendering, Paris, France, 221–231 (1993).Google Scholar
- Miller, G. S., Hoffman, C. R.: Illumination and Reflection Maps: Simulated Objects in Simulated and Real Environments, SIGGRAPH’84: Advanced Computer Graphics Animation Seminar Notes, (1984)Google Scholar
- Rushmeier, H. E.: Realistic Image Synthesis for Scenes with Radiatively Participating Media, PhD thesis (1988).Google Scholar
- Rushmeier, H: E., Patterson, C., Veerasamy, A.: Geometric Simplification for Indirect Illumination Calculations, Graphics Interface’93, 227–236 (1993).Google Scholar
- Shirley, P.: A Ray Tracing Method for Illumination Calculation in Diffuse Specular Scenes, Graphics Interface’90, 205–212 (1990).Google Scholar
- Shirley, P.: Physically Based Lighting Calculations for Computer Graphics, PhD thesis, Urbana-Champaign (1991).Google Scholar
- Sillion, F., Puech, C.: A general two-pass method integrating specular and diffuse reflection, ACM Computer graphics (1989), SIGGRAPH’89.Google Scholar
- Wallace, J. R., Cohen, M. F., Greenberg, D. P.: A two-pass solution to the rendering equation: A synthesis of ray tracing and radiosity methods, ACM Computer Graphics 21(4), 311–320, (1987), SIGGRAPH ’87.Google Scholar