hide
Free keywords:
-
Abstract:
Visibility computations are the most time-consuming part of global
illumination algorithms. The cost is amplified by the fact that
quite often identical or similar information is recomputed multiple
times. In particular this is the case when multiple images of the
same scene are to be generated under varying lighting conditions
and/or viewpoints. But even for a single image with static
illumination, the computations could be accelerated by reusing
visibility information for many different light paths.
In this report we describe a general method of precomputing, storing,
and reusing visibility information for light transport in a number
of different types of scenes. In particular, we consider general
parametric surfaces, triangle meshes without a global
parameterization, and participating media.
We also reorder the light transport in such a way that the
visibility information is accessed in structured memory access
patterns. This yields a method that is well suited for SIMD-style
parallelization of the light transport, and can efficiently be
implemented both in software and using graphics hardware. We finally
demonstrate applications of the method to highly efficient
precomputation of BRDFs, bidirectional texture functions, light
fields, as well as near-interactive volume lighting.
