Systems and methods for robust sampling for real-time relighting of objects in natural lighting environments

摘要

The present invention is directed to a enhanced Precomputed Radiance Transfer (PRT) system employing an algorithm to compute a PRT signal over a surface mesh and subdividing facets of the mesh to increase the number of surface vertices such that the spatial variation of the transfer signal is resolved sufficiently everywhere on the surface. The method of this system ensures that radiance transfer shading produces colors of sufficient accuracy all over the surface. In certain embodiments, transfer is computed only at surface vertices, although this does result in a certain amount of acceptable aliasing and blurring of surface lighting detail in regions where the tessellation is too coarse. Furthermore, the method comprises a spatial and density sampling techniques that measures the transfer signal to a desirable appropriate resolution while minimizing aliasing. Once computed, the signal is represented as compactly as possible to minimize storage and runtime computation requirements.