We present a method for determining a posteriori bounds and estimates for local and total errors in radiosity solutions. The ability to obtain bounds and estimates for the total error is crucial for reliably judging the acceptability of a solution. Realistic estimates of the local error improve the efficiency of adaptive radiosity algorithms, such as hierarchical radiosity, by indicating where adaptive refinement is necessary. First, we describe a hierarchical radiosity algorithm that computes conservative lower and upper bounds on the exact radiosity function, as well as on the approximate solution. These bounds account for the propagation of errors due to interreflections, and provide a conservative upper bound on the error. We also describe a non-conservative version of the same algorithm that is capable of computing tighter bounds, from which more realistic error estimates can be obtained. Finally, we derive an expression for the effect of a particular interaction on the total error. This yields a new error-driven refinement strategy for hierarchical radiosity, which is shown to be superior to brightness-weighted refinement.
|Original language||American English|
|Title of host publication||Proceedings of the 21st Annual Conference on Computer Graphics and Interactive Techniques, SIGGRAPH 1994|
|Publisher||Association for Computing Machinery, Inc|
|Number of pages||8|
|ISBN (Electronic)||0897916670, 9780897916677|
|State||Published - 24 Jul 1994|
|Event||21st Annual Conference on Computer Graphics and Interactive Techniques, SIGGRAPH 1994 - Orlando, United States|
Duration: 24 Jul 1994 → 29 Jul 1994
|Name||Proceedings of the 21st Annual Conference on Computer Graphics and Interactive Techniques, SIGGRAPH 1994|
|Conference||21st Annual Conference on Computer Graphics and Interactive Techniques, SIGGRAPH 1994|
|Period||24/07/94 → 29/07/94|
Bibliographical noteFunding Information:
Special thanks go to Jim Arvo: without his encouragement and advice this paper would not have been written. We would also like to thank Richard Lobb and Charlie Van Loan for helpful discussions and for reviewing the manuscript. The comments provided by the anonymous reviewers have helped greatly to improve this paper. This work was supported by the NSF grant, “Interactive Computer Graphics Input and Display Techniques” (CCR-8617880), by the NSF/DARPA Science and Technology Center for Computer Graphics and Scientific Visualization (ASC-8920219), and by generous donations of equipment from Hewlett-Packard.
© ACM 1994.
- A posteriori error bounds and estimates
- Adaptive refinement
- Global illumination
- Hierarchical radiosity