Hierarchical BSSRDF Evaluation Our new hierarchical evaluation technique is fast and it integrates seamlessly with traditional global illumination techniques such as photon mapping used in this Cornell box image. Note the light bleeding through the translucent box.

Abstract

This paper introduces an efficient two-pass rendering technique for translucent materials. We decouple the computation of irradiance at the surface from the evaluation of scattering inside the material. This is done by splitting the evaluation into two passes, where the first pass consists of computing the irradiance at selected points on the surface. The second pass uses a rapid hierarchical integration technique to evaluate a diffusion approximation based on the irradiance samples. This approach is substantially faster than previous methods for rendering translucent materials, and it has the advantage that it integrates seamlessly with both scanline rendering and global illumination methods. We show several images and animations from our implementation that demonstrate that the approach is both fast and robust, making it suitable for rendering translucent materials in production.

Reference:
Henrik Wann Jensen and Juan Buhler:
"A Rapid Hierarchical Rendering Technique for Translucent Materials".
Proceedings of SIGGRAPH'2002

fast_bssrdf.pdf (1.0MB)