Adaptive Numerical Cumulative Distribution Functions for Efficient Importance Sampling [article]

Jason Lawrence, Szymon Rusinkiewicz, Ravi Ramamoorthi
2005 Symposium on Rendering  
As image-based surface reflectance and illumination gain wider use in physically-based rendering systems, it is becoming more critical to provide representations that allow sampling light paths according to the distribution of energy in these high-dimensional measured functions. In this paper, we apply algorithms traditionally used for curve approximation to reduce the size of a multidimensional tabulated Cumulative Distribution Function (CDF) by one to three orders of magnitude without
more » ... sing its fidelity. These adaptive representations enable new algorithms for sampling environment maps according to the local orientation of the surface and for multiple importance sampling of image-based lighting and measured BRDFs.
doi:10.2312/egwr/egsr05/011-020 fatcat:q3ecxpgtzrhmrdt2cw6dwl36fi