High-Fidelity Radiosity Rendering at Interactive Rates
Existing radiosity rendering algorithms achieve interactivity or high fidelity, but not both. Most radiosity renderers optimize interactivity by converting to a polygonal representation and Gouraud interpolating shading samples, thus sacrificing visual fidelity. A few renderers achieve improved fidelity by performing a per-pixel irradiance “gather” operation, much as in ray-tracing. This approach does not achieve interactive frame rates on existing hardware.
This paper bridges the gap, by describing a data structure and algorithm which enable interactive, high-fidelity rendering of radiosity solutions. Our algorithm “factors” the radiosity rendering computation into two components: an offline phase, in which a per-surface representation of irradiance is constructed; and an online phase, in which this representation is rapidly queried, in parallel, to produce a radiosity value at each pixel. The key components of the offline phase are a heuristic discontinuity ranking algorithm, which identifies the strongest discontinuities, and a hybrid quadtree-mesh data structure which prevents combinatorial interactions between most discontinuities. The online phase involves a novel use of perspective-correct texture-mapping hardware to produce nonlinear, analytic shading effects.
KeywordsComputer Graphic Graphic Hardware Global Illumination Online Phase Offline Phase
Unable to display preview. Download preview PDF.
- Akeley, K. RealityEngine Graphics. Computer Graphics (Proc. Siggraph’ 93) (1993), 109–116.Google Scholar
- Arvo, J. The Irradiance Jacobian for Partially Occluded Polyhedral Sources. In Proceedings of SIGGRAPH ’94 (Orlando, Florida, July 24–29, 1994) (July 1994), A. Glassner, Ed., Computer Graphics Proceedings, Annual Conference Series, ACM SIGGRAPH, ACM Press, pp. 343–350. ISBN 0-89791-667-0.Google Scholar
- Drettakis, G., and Fiume, E. A Fast Shadow Algorithm for Area Light Sources Using Backprojection. In Proceedings of SIGGRAPH ’94 (Orlando, Florida, July 24-29, 1994) (July 1994), A. Glassner, Ed., Computer Graphics Proceedings, Annual Conference Series, ACM SIGGRAPH, ACM Press, pp. 223–230. ISBN 0-89791-667-0.Google Scholar
- Fuchs, H., Poulton, J., Eyles, J., Greer, T., Goldfeather, J., Ellsworth, D., Molnar, S., Turk, G., Tebbs, B., and Israel, L. Pixel-Planes 5: A Heterogeneous Multiprocessor Graphics System Using Processor-Enhanced Memories. Computer Graphics (Proc. Siggraph ’89) 23, 3 (1989), 79–88.CrossRefGoogle Scholar
- Garlick, B., Baum, D. R., and Winget, J. M. Interactive Viewing of Large Geometric Databases Using Multiprocessor Graphics Workstations. Siggraph ’90 Course Notes (Parallel Algorithms and Architectures for 3D Image Generation) (1990).Google Scholar
- Gortler, S., Schroder, P., Cohen, M., and Hanrahan, P. Wavelet radiosity. Computer Graphics (Proc. Siggraph ’93) (August 1993), 221–230.Google Scholar
- Haines, E., and Wallace, J. Shaft Culling for Efficient Ray-Traced Radiosity. In Proc. 2nd Eurographics Workshop on Rendering (May 1991).Google Scholar
- Hanrahan, P., and Haeberli, P. E. Direct WYSIWYG Painting and Texturing on 3D Shapes. In Computer Graphics (SIGGRAPH ’90 Proceedings) (Aug. 1990), F. Baskett, Ed., vol. 24, pp. 215–223.Google Scholar
- Heckbert, P. Discontinuity Meshing for Radiosity. Third Eurographics Workshop on Rendering (May 1992), 203–226.Google Scholar
- Holzschuch, N., and Sillion, F. Accurate Computation of the Radiosity Gradient for Constant and Linear Emitters. In Rendering Techniques ’95 (Proceedings of the Sixth Eurographics Workshop on Rendering) (New York, 1995), P. M. Hanrahan and W. Purgathofer, Eds., Springer-Verlag, pp. 186–195.Google Scholar
- Lischinski, D. Incremental Delaunay Triangulation. In Graphics Gems IV, P. Heckbert, Ed. AP Professional, 1994, pp. 47–59.Google Scholar
- Lischinski, D., Tampieri, F., and Greenberg, D. P. Combining Hierarchical Radiosity and Discontinuity Meshing. Computer Graphics (Proc. Siggraph ’93) 27 (1993).Google Scholar
- Neider, J., Davis, T., and Woo, M. OpenGL Programming Guide. Addison-Wesley, 1993.Google Scholar
- Salesin, D., Lischinski, D., and Derose, T. Reconstructing Illumination Functions with Selected Discontinuities. In Proc. 3rd Eurographics Workshop on Rendering (May 1992), pp. 99–112.Google Scholar
- Sillion, F. X., and Puech, C. A General Two-Pass Method Integrating Specular and Diffuse Reflection. In Computer Graphics (SIGGRAPH ’89 Proceedings) (July 1989), J. Lane, Ed., vol. 23, pp. 335–344.Google Scholar
- Smits, B., Arvo, J., and Greenberg, D. A Clustering Algorithm for Radiosity in Complex Environments. Computer Graphics (Proc. Siggraph ’94) 28 (1994).Google Scholar
- Teller, S., and Hanrahan, P. Global Visibility Algorithms for Illumination Computations. Computer Graphics (Proc. Siggraph ’93) 27 (1993), 239–246.Google Scholar
- Ward, G. J., and Heckbert, P. Irradiance Gradients. Third Eurographics Workshop on Rendering (May 1992), 85–98.Google Scholar