Publikation
Revisiting Controlled Mixture Sampling for Rendering Applications
Qingqin Hua; Pascal Grittmann; Philipp Slusallek
In: ACM Transactions on Graphics (TOG), Vol. 42, Page 13, Online, 2023.
Zusammenfassung
Monte Carlo rendering makes heavy use of mixture sampling and multiple
importance sampling (MIS). Previous work has shown that control variates
can be used to make such mixtures more efficient and more robust. However,
the existing approaches failed to yield practical applications, chiefly because
their underlying theory is based on the unrealistic assumption that a single
mixture is optimized for a single integral. This is in stark contrast with
rendering reality, where millions of integrals are computed—one per pixel—
and each is infinitely recursive. We adapt and extend the theory introduced
by previous work to tackle the challenges of real-world rendering applications. We achieve robust mixture sampling and (approximately) optimal MIS
weighting for common applications such as light selection, BSDF sampling,
and path guiding