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Shadows and Soft Shadows with Participating Media Using Splatting
April-June 2003 (vol. 9 no. 2)
pp. 139-149
Roger Crawfis, IEEE Computer Society

Abstract—This paper describes an efficient algorithm to model the light attenuation due to a participating media with low albedo. Here, we consider the light attenuation along a ray, as well as the light attenuation emanating from a surface. The light attenuation is modeled using a splatting volume renderer for both the viewer and the light source. During the rendering, a 2D shadow buffer accumulates the light attenuation. We first summarize the basic shadow algorithm using splatting [30]. Then, an extension of the basic shadow algorithm for projective textured light sources is described. The main part of this paper is an analytic soft shadow algorithm based on convolution techniques. We describe and discuss the soft shadow algorithm, and generate soft shadows, including umbra and penumbra, for extended light sources.

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Index Terms:
Volume rendering, splatting, shadows, soft shadows, participating media, illumination.
Caixia Zhang, Roger Crawfis, "Shadows and Soft Shadows with Participating Media Using Splatting," IEEE Transactions on Visualization and Computer Graphics, vol. 9, no. 2, pp. 139-149, April-June 2003, doi:10.1109/TVCG.2003.10006
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