Forward Shadow Mapping

  • Hansong Zhang
Part of the Eurographics book series (EUROGRAPH)


Forward shadow mapping is a new approach to real-time shadow generation. The traditional shadow map algorithm maps the pixels in the eye’s view backward into the depth buffers of light sources (i.e. shadow maps), which is similiar to and often implemented as an extension to texture mapping. Our algorithm reverses this process by using 3-D image warping techniques to transform shadow map pixels forward into the eye’s view to directly indicate which pixels are lit; it does not interfere with normal texture mapping and easily supports antialiased shadow edges and projective textures. Access to shadow maps and projective textures is in pixel-sequential order. This algorithm has advantages when speed of texture mapping becomes the performance bottleneck, which is often the case in visual simulation and game applications.


Computer Graphic Texture Mapping Depth Buffer Soft Shadow Destination Image 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Wien 1998

Authors and Affiliations

  • Hansong Zhang
    • 1
  1. 1.Department of Computer ScienceUniversity of North CarolinaChapel HillUSA

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