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http://dx.doi.org/10.7583/JKGS.2020.20.3.65

Soft Shadow with integral Filtering  

Zhang, Bo (Dept. of Media, Soongsil University)
Oh, KyoungSu (Dept. of Media, Soongsil University)
Publication Information
Journal of Korea Game Society / v.20, no.3, 2020 , pp. 65-74 More about this Journal
Abstract
In the shadow map method, if the shadow map is magnified, the shadow has a jagged silhouette. Herein, we propose a soft shadow method that filters reshaped silhouettes analytically. First, the shadow silhouette is reshaped through sub-texel edge detection, which is based on linear or quadratic curve models. Second, an integral shadow filtering algorithm is used to accurately obtain the average shadow intensity from a definite integral estimation. The implementation demonstrates that our solution can effectively eliminate jagged aliasing and efficiently generate soft shadows.
Keywords
Shadow mapping; Soft shadow; Magnification; Sub-pixel edge detection; Real-time rendering;
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1 Lance Williams, "Casting curved shadows on curved surfaces", SIGGRAPH '78: Proceedings of the 5th annual conference on Computer graphics and interactive techniques, pp270-274, 1978.
2 Thomas Annen, Tom Mertens, Philippe Bekaert, Hans-Peter Seidel, and Jan Kautz. "Convolution shadow maps", EGSR'07: Proceedings of the 18th Eurographics conference on Rendering Techniques, pp51-60, 2007.
3 Thomas Annen, Tom Mertens, Hans-Peter Seidel, Eddy Flerackers, Jan Kautz, "Exponential shadow maps", GI '08: Proceedings of Graphics Interface, pp155-161, 2008.
4 William Donnelly, Andrew Lauritzen, "Variance shadow maps", I3D '06: Proceedings of the 2006 symposium on Interactive 3D graphics and games, pp161-165, 2006.
5 Andrew Lauritzen, "Summed-Area Variance Shadow Maps", In GPU Gems 3, pp157-182, 2008.
6 Christoph Peters, Reinhard Klein, "Moment shadow mapping", i3D '15: Proceedings of the 19th Symposium on Interactive 3D Graphics and Games, pp7-14, 2015.
7 Agustin Trujillo-Pino, Karl Krissian, Miguel AlemaN-Flores, Daniel Santana-CedreS, "Accurate subpixel edge location based on partial area effect", Image and Vision Computing, pp72-90, 2013.   DOI
8 Irwin Sobel, G. Feldman, "A $3{\times}3$ isotropic gradient operator for image processing", A Talk at the Stanford Artificial Project, pp271-272, 1968.
9 William T. Reeves, David H. Salesin, Robert L. Cook, "Rendering antialiased shadows with depth maps", SIGGRAPH '87: Proceedings of the 14th annual conference on Computer graphics and interactive techniques, Vol. 21, No. 4, pp283-291, 1987.
10 Randima Fernando, "Percentage-Closer Soft Shadows", SIGGRAPH '05: ACM SIGGRAPH 2005 Sketches, 2005.
11 Vladimir Bondarev, "Shadow map silhouette revectorization", I3D '14: Proceedings of the 18th meeting of the ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games, 2014.
12 Macedo M. C. F., Apolinario Jr. A. L., Aguero K. A., "Revectorization-based soft shadow mapping", Computer Graphics Forum, 2019