Issue No. 02 - April-June (2003 vol. 9)
Joe Kniss , IEEE Computer Society
Simon Premoze , IEEE Computer Society
Charles Hansen , IEEE Computer Society
Peter Shirley , IEEE Computer Society
Allen McPherson , IEEE Computer Society
<p><b>Abstract</b>—Direct volume rendering is a commonly used technique in visualization applications. Many of these applications require sophisticated shading models to capture subtle lighting effects and characteristics of volumetric data and materials. For many volumes, homogeneous regions pose problems for typical gradient-based surface shading. Many common objects and natural phenomena exhibit visual quality that cannot be captured using simple lighting models or cannot be solved at interactive rates using more sophisticated methods. We present a simple yet effective interactive shading model which captures volumetric light attenuation effects that incorporates volumetric shadows, an approximation to phase functions, an approximation to forward scattering, and chromatic attenuation that provides the subtle appearance of translucency. We also present a technique for volume displacement or perturbation that allows realistic interactive modeling of high frequency detail for both real and synthetic volumetric data.</p>
Volume rendering, shading model, volume modeling, procedural modeling, fur, clouds, volume perturbation.
P. Shirley, A. McPherson, C. Hansen, S. Premoze and J. Kniss, "A Model for Volume Lighting and Modeling," in IEEE Transactions on Visualization & Computer Graphics, vol. 9, no. , pp. 150-162, 2003.