Radiance caching for efficient global illumination computation.

Jaroslav Krivánek; Pascal Gautron; Sumanta Pattanaik; Kadi Bouatouch

doi:10.1109/tvcg.2005.83

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Radiance caching for efficient global illumination computation.

Jaroslav Krivánek·Pascal Gautron·Sumanta Pattanaik·Kadi Bouatouch

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Abstract

In this paper, we present a ray tracing-based method for accelerated global illumination computation in scenes with low-frequency glossy BRDFs. The method is based on sparse sampling, caching, and interpolating radiance on glossy surfaces. In particular, we extend the irradiance caching scheme proposed by Ward et al. to cache and interpolate directional incoming radiance instead of irradiance. The incoming radiance at a point is represented by a vector of coefficients with respect to a hemispherical or spherical basis. The surfaces suitable for interpolation are selected automatically according to the roughness of their BRDF. We also propose a novel method for computing translational radiance gradient at a point.

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Algorithms Computer Graphics Image Enhancement Image Interpretation, Computer-Assisted Imaging, Three-Dimensional Information Storage and Retrieval Lighting Evaluation Study Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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Jaroslav Krivánek, Pascal Gautron, Sumanta Pattanaik, Kadi Bouatouch. Radiance caching for efficient global illumination computation.. https://doi.org/10.1109/tvcg.2005.83

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