Manifold Next Event Estimation

• Published in: Computer graphics forum Vol. 34; no. 4; pp. 87 - 97
• Main Authors: Hanika, Johannes, Droske, Marc, Fascione, Luca
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.07.2015
• Subjects: Categories and Subject Descriptors (according to ACM CCS); Caustics; Computer graphics; Computer simulation; Construction; I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism-Raytracing; Importance sampling; Manifolds; Monte Carlo methods; Monte Carlo simulation; Sampling; Studies; Weight reduction; United States > US
• ISSN: 0167-7055; 1467-8659
• DOI: 10.1111/cgf.12681

We present manifold next event estimation (MNEE), a specialised technique for Monte Carlo light transport simulation to render refractive caustics by connecting surfaces to light sources (next event estimation) across transmissive interfaces. We employ correlated sampling by means of a perturbation strategy to explore all half vectors in the case of rough transmission while remaining outside of the context of Markov chain Monte Carlo, improving temporal stability. MNEE builds on differential geometry and manifold walks. It is very lightweight in its memory requirements, as it does not use light caching methods such as photon maps or importance sampling records. The method integrates seamlessly with existing Monte Carlo estimators via multiple importance sampling.