Weighted Multipass Methods for Global Illumination
Frank Suykens, Yves Willems · Computer Graphics Forum · 1999
In multipass rendering, care has to be taken to include all light transport only once in the final solution. Therefore the different methods in current multipass configurations handle a perfectly disjunct part of the light transport. In this paper a Monte Carlo variance reduction technique is presented that probabilistically weights overlapping transport between different methods. A good heuristic for the weights is derived so that strengths of the respective methods are retained. The technique is applied to a combination of radiosity and bidirectional path tracing and significant improvement is obtained over the non‐weighted combination. This method promises to be a very useful extension to other multipass algorithms as well.