ABSTRACT
This paper presents a scalable, adaptive algorithm for direct illumination in scenes with many area light sources. Instead of presampling light sources into massive point lights like previous multilight algorithms, the algorithm builds a tree structure for all area lights using agglomerative hierarchical clustering algorithm and evaluates direct illumination by a collection of tree nodes. Each node represents a light cluster and its output radiance is computed using two estimation methods. For each pixel point, a node set is found adaptively through tree traversal guided by error estimation and overall radiance variation. As the algorithm works on area lights directly, the error incurred by converting area lights to point lights is avoided. The experimental results show that our algorithm can generate images with higher fidelity and is more efficient compared with existing point light based multi-light algorithms.
- Arvo, J. 1994. The irradiance jacobian for partially occluded polyhedral sources. In SIGGRAPH '94: Proceedings of the 21st annual conference on Computer graphics and interactive techniques, ACM, New York, NY, USA, 343--350. Google ScholarDigital Library
- Arvo, J. 2004. Approximate soft shadows win an image-space flood-fill algorithm. Computer Graphics Forum 23, 9, 271--279.Google ScholarCross Ref
- Donikian, M., Walter, B., Bala, K., Fernandez, S., and Greenberg, D. P. 2006. Accurate direct illumination using iterative adaptive sampling. IEEE Transactions on Visualization and Computer Graphics 12, 353--364. Google ScholarDigital Library
- Guennebaud, G., Barthe, L., and Paulin, M. 2006. Realtime soft shadow mapping by backprojection. In In Eurographics Symposium on Rendering, 227--234. Google ScholarDigital Library
- Hašan, M., Pellacini, F., and Bala, K. 2007. Matrix row-column sampling for the many-light problem. ACM Trans. Graph. 26, 3, 26. Google ScholarDigital Library
- Paquette, E., Poulin, P., and Drettakis, G. 1998. A light hierarchy for fast rendering of scenes with many lights. Computer Graphics Forum 17, 3, 63--74.Google ScholarCross Ref
- Shirley, P., Wang, C., and Zimmerman, K. 1996. Monte carlo techniques for direct lighting calculations. ACM Trans. Graph. 15, 1, 1--36. Google ScholarDigital Library
- Snyder, J. 1996. Area light sources for real-time graphics. Technical Report, MSR-TR-96-11.Google Scholar
- Walter, B., Fernandez, S., Arbree, A., Bala, K., Donikian, M., and Greenberg, D. P. 2005. Lightcuts: a scalable approach to illumination. In SIGGRAPH '05: ACM SIGGRAPH 2005 Papers, ACM, New York, NY, USA, 1098--1107. Google ScholarDigital Library
- Walter, B., Arbree, A., Bala, K., and Greenberg, D. P. 2006. Multidimensional lightcuts. In SIGGRAPH '06: ACM SIGGRAPH 2006 Papers, ACM, New York, NY, USA, 1081--1088. Google ScholarDigital Library
- Wang, R., Wang, R., Zhou, K., Pan, M., and Bao, H. 2009. An efficient gpu-based approach for interactive global illumination. In SIGGRAPH '09: ACM SIGGRAPH 2009 papers, ACM, New York, NY, USA, 1--8. Google ScholarDigital Library
- Ward, G. 1991. Adaptive shadow testing for ray tracing. In Proceedings of the Second Eurographics Workshop on Rendering.Google Scholar
- Zaninetti, J. 1999. An adaptive method for area light sources and daylight in ray tracing. Computer Graphics Forum 18, 12, 139--150.Google ScholarCross Ref
Index Terms
- Direct illumination for many area lights
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