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An Illumination Model for a Skin Layer Bounded by Rough Surfaces

  • Jos Stam
Part of the Eurographics book series (EUROGRAPH)

Abstract

In this paper we present a novel illumination model that takes into account multiple anisotropic scattering in a layer bounded by two rough surfaces. We compute the model by a discrete-ordinate solution of the equation of radiative transfer. This approach is orders of magnitude faster than a Monte Carlo simulation and does not suffer from any noisy artifacts. By fitting low order splines to our results we are able to build analytical shaders. This is highly desirable since animators typically want to texture map the parameters of such a shader for higher realism. We apply our model to the important problem of rendering human skin. Our model does not seem to have appeared before in the optics literature. Most previous models did not handle rough surfaces at the skin’s boundary. Also we introduce a simple analytical bidirectional transmittance distribution function (BTDF) for an isotropic rough surface by generalizing the Cook-Torrance model.

Keywords

Radiative Transfer Phase Function Skin Layer Global Illumination Cosine Series 
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

  • Jos Stam
    • 1
  1. 1.Alias | wavefrontSeattleUSA

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