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Photon Beam Diffusion: A Hybrid Monte Carlo Method for Subsurface ScatteringRalf Habel, Per H. Christensen, Wojciech JaroszJune 2013We present photon beam diffusion, an efficient numerical method for accurately rendering translucent materials. Our approach interprets incident light as a continuous beam of photons inside the material. Numerically integrating diffusion from such extended sources has long been assumed computationally prohibitive, leading to the ubiquitous single-depth dipole approximation and the recent analytic sum-of-Gaussians approach employed ... more Paper (PDF) Additional materials: [PBD_matlab_v1.03.zip], [supplemental-theory.pdf]Published in Computer Graphics Forum (Proceedings of the Eurographics Symposium on Rendering 2013), volume 32, number 4. Eurographics / Blackwell Publishers, June 2013. (Zaragoza, Spain, June 19-21.). Equation 13 amended July 2013. | |

The Path to Path-Traced MoviesPer H. Christensen, Wojciech JaroszOctober 2016Path tracing is one of several techniques to render photorealistic images by simulating the physics of light propagation within a scene. The roots of path tracing are outside of computer graphics, in the Monte Carlo simulations developed for neutron transport. A great strength of path tracing is that it is conceptually, mathematically, and often-times algorithmically ... more Paper (PDF) Appeared as: Foundation and Trends in Computer Graphics and Vision, volume 10, number 2, pages 103-175. | |

Orthogonal Array Sampling for Monte Carlo RenderingWojciech Jarosz, Afnan Enayet, Andrew Kensler, Charlie Kilpatrick, Per ChristensenJuly 2019We generalize N-rooks, jittered, and (correlated) multi-jittered sampling to higher dimensions by importing and improving upon a class of techniques called orthogonal arrays from the statistics literature. Renderers typically combine or "pad" a collection of lower-dimensional (e.g. 2D and 1D) stratified patterns to form higher-dimensional samples for integration. ... more Paper (PDF) Additional materials: [images.tar.xz], [supplemental.pdf] |