Estimating Local Beckmann Roughness for Complex BSDFs

Nicolas Holzschuch 1 Anton Kaplanyan 2 Johannes Hanika 3, 4 Carsten Dachsbacher 4
1 MAVERICK - Models and Algorithms for Visualization and Rendering
Inria Grenoble - Rhône-Alpes, LJK - Laboratoire Jean Kuntzmann, INPG - Institut National Polytechnique de Grenoble
Abstract : Many light transport related techniques require an analysis of the blur width of light scattering at a path vertex, for instance a Beck-mann roughness. Such use cases are for instance analysis of expected variance (and potential biased countermeasures in production rendering), radiance caching or directionally dependent virtual point light sources, or determination of step sizes in the path space Metropolis light transport framework: recent advanced mutation strategies for Metropolis Light Transport [Veach 1997], such as Manifold Exploration [Jakob 2013] and Half Vector Space Light Transport [Kaplanyan et al. 2014] employ local curvature of the BSDFs (such as an average Beckmann roughness) at all interactions along the path in order to determine an optimal mutation step size. A single average Beckmann roughness, however, can be a bad fit for complex measured materials (such as [Matusik et al. 2003]) and, moreover, such curvature is completely undefined for layered materials as it depends on the active scattering layer. We propose a robust estimation of local curvature for BSDFs of any complexity by using local Beckmann approximations, taking into account additional factors such as both incident and outgoing direction.
Document type :
Conference papers
Complete list of metadatas

Cited literature [6 references]  Display  Hide  Download


https://hal.inria.fr/hal-01312227
Contributor : Nicolas Holzschuch <>
Submitted on : Wednesday, May 4, 2016 - 11:12:00 PM
Last modification on : Monday, February 18, 2019 - 11:54:13 AM
Long-term archiving on : Tuesday, November 15, 2016 - 8:32:30 PM

Files

talk_abstract.pdf
Files produced by the author(s)

Identifiers

Collections

Citation

Nicolas Holzschuch, Anton Kaplanyan, Johannes Hanika, Carsten Dachsbacher. Estimating Local Beckmann Roughness for Complex BSDFs. ACM Siggraph talks, Jul 2016, Anaheim, CA, United States. ⟨10.1145/2897839.2927416⟩. ⟨hal-01312227⟩

Share

Metrics

Record views

1316

Files downloads

567