Occlusion Textures for Plausible Soft Shadows *

This paper presents a new approach to compute plausible soft shadows for complex dynamic scenes and rectangular light sources. We estimate the occlusion at each point of the scene using prefiltered occlusion textures, which dynamically approximate the scene geometry. The algorithm is fast and its performance independent of the light's size. Being image‐based, it is mostly independent of the scene complexity and type. No a priori information is needed, and there is no caster/receiver separation. This makes the method appealing and easy to use.

[1]  Mika Hirvikorpi,et al.  Approximate Soft Shadows win an Image‐Space Flood‐Fill Algorithm , 2004, Comput. Graph. Forum.

[2]  Michael Wimmer,et al.  Queried virtual shadow maps , 2007, SI3D.

[3]  Lance Williams,et al.  Casting curved shadows on curved surfaces , 1978, SIGGRAPH.

[4]  Anselmo Lastra,et al.  Fast Summed‐Area Table Generation and its Applications , 2005, Comput. Graph. Forum.

[5]  Peter Shirley,et al.  Single Sample Soft Shadows , 2008 .

[6]  Frédo Durand,et al.  A frequency analysis of light transport , 2005, SIGGRAPH '05.

[7]  Charles D. Hansen,et al.  Penumbra Maps: Approximate Soft Shadows in Real-Time , 2003, Rendering Techniques.

[8]  Dinesh Manocha,et al.  Warping and partitioning for low error shadow maps , 2006, EGSR '06.

[9]  Artis Gravir,et al.  N-Buffers for efcient depth map query , 2005 .

[10]  François X. Sillion,et al.  A Survey of Real‐time Soft Shadows Algorithms , 2003, Comput. Graph. Forum.

[11]  Tomas Akenine-Möller,et al.  An optimized soft shadow volume algorithm with real-time performance , 2003, HWWS '03.

[12]  Hujun Bao,et al.  Real-time voxelization for complex polygonal models , 2004, 12th Pacific Conference on Computer Graphics and Applications, 2004. PG 2004. Proceedings..

[13]  Andrew Lauritzen,et al.  Variance shadow maps , 2006, I3D '06.

[14]  Hans-Peter Seidel,et al.  Hardware-accelerated rendering of antialiased shadows with shadow maps , 2001, Proceedings. Computer Graphics International 2001.

[15]  Franklin C. Crow,et al.  Shadow algorithms for computer graphics , 1977, SIGGRAPH.

[16]  B Keating,et al.  Shadow penumbras by depth-dependent filtering , 1999, SIGGRAPH 1999.

[17]  Pierre Poulin,et al.  A survey of shadow algorithms , 1990, IEEE Computer Graphics and Applications.

[18]  László Szirmay-Kalos,et al.  Real-time Soft Shadows with Shadow Accumulation , 2006, Eurographics.

[19]  Jürgen Döllner,et al.  Real-Time Soft Shadows Using a Single Light Sample , 2003, WSCG.

[20]  Tomas Akenine-Möller,et al.  A geometry-based soft shadow volume algorithm using graphics hardware , 2003 .

[21]  Elmar Eisemann,et al.  Visibility Sampling on GPU and Applications , 2007, Comput. Graph. Forum.

[22]  Elmar Eisemann,et al.  Plausible Image Based Soft Shadows Using Occlusion Textures , 2006, 2006 19th Brazilian Symposium on Computer Graphics and Image Processing.

[23]  Cláudio T. Silva,et al.  Real-time soft shadows with cone culling , 2006, SIGGRAPH '06.

[24]  Kun Zhou,et al.  Precomputed shadow fields for dynamic scenes , 2005, ACM Trans. Graph..

[25]  Loïc Barthe,et al.  Real-time soft shadow mapping by backprojection , 2006, EGSR '06.

[26]  Tomas Akenine-Möller,et al.  Approximate Soft Shadows on Arbitrary Surfaces using Penumbra Wedges , 2002, Rendering Techniques.

[27]  Marc Stamminger,et al.  Bitmask Soft Shadows , 2007, Comput. Graph. Forum.

[28]  François X. Sillion,et al.  Fast calculation of soft shadow textures using convolution , 1998, SIGGRAPH.

[29]  Franklin C. Crow,et al.  Summed-area tables for texture mapping , 1984, SIGGRAPH.

[30]  David Salesin,et al.  Rendering antialiased shadows with depth maps , 1987, SIGGRAPH.

[31]  Xavier Décoret.  N‐Buffers for efficient depth map query , 2005, Comput. Graph. Forum.

[32]  Elmar Eisemann,et al.  Fast scene voxelization and applications , 2006, I3D '06.

[33]  Lance Williams,et al.  Pyramidal parametrics , 1983, SIGGRAPH.

[34]  Hans-Peter Seidel,et al.  Single Sample Soft Shadows Using Depth Maps , 2002, Graphics Interface.

[35]  Frédo Durand,et al.  Rendering Fake Soft Shadows with Smoothies , 2003, Rendering Techniques.

[36]  Laurent Moll,et al.  Efficient image-based methods for rendering soft shadows , 2000, SIGGRAPH.

[37]  Pierre Poulin,et al.  Soft shadows from extended light sources with penumbra deep shadow maps , 2005, Graphics Interface.

[38]  Charles D. Hansen,et al.  Soft Shadow Maps: Efficient Sampling of Light Source Visibility , 2006, Comput. Graph. Forum.

[39]  Dinesh Manocha,et al.  CC shadow volumes , 2004, SIGGRAPH '04.