Opacity Shadow Maps

  • Tae-Yong Kim
  • Ulrich Neumann
Part of the Eurographics book series (EUROGRAPH)


Opacity shadow maps approximate light transmittance inside a complex volume with a set of planar opacity maps. A volume made of standard primitives (points, lines, and polygons) is sliced and rendered with graphics hardware to each opacity map that stores alpha values instead of traditionally used depth values. The alpha values are sampled in the maps enclosing each primitive point and interpolated for shadow computation. The algorithm is memory efficient and extensively exploits existing graphics hardware. The method is suited for generation of self-shadows in discontinuous volumes with explicit geometry, such as foliage, fur, and hairs. Continuous volumes such as clouds and smoke may also benefit from the approach.


Transmittance Function Graphic Hardware Depth Buffer Discontinuous Volume Volumetric Object 
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 2001

Authors and Affiliations

  • Tae-Yong Kim
    • 1
  • Ulrich Neumann
    • 1
  1. 1.Computer Graphics and Immersive Technology Laboratory, Integrated Media Systems CenterUniversity of Southern CaliforniaUSA

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