Cornell University Program of Computer Graphics
Galerkin radiosity: A higher order solution method for global illumination.Harold R. Zatz.
In James T. Kajiya, editor, SIGGRAPH 93 Conference Proceedings, Computer Graphics Proceedings, Annual Conference Series, pages 213--220. ACM SIGGRAPH, ACM Press, August 1993.
This paper presents an alternative radiosity formulation using piecewise smooth radiance functions that incorporates curved surfaces directly. Using the Galerkin integral equation technique as a mathematical foundation, surface radiance functions are approximated by polynomials. This model eliminates the need for a posteriori rendering interpolation, and allows the direct use of non-planar parametric surfaces. Convergence problems due to singularities in the radiosity kernel are analyzed and rectified, and sources of approximation error are examined. The incorporation of a shadow masking technique vastly reduces the need for meshing and associated storage space-accurate radiosity calculations can often be made with no meshing. The technique is demonstrated on traditional radiosity scenes, as well as environments with untessellated curved surfaces.
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