arXiv subjects

Matthias Raab

Publications and source records attributed to Matthias Raab.

2 recordsLinked to original sources

arXiv2026

The Minimal Retroreflective Microfacet Model

We present the Minimal Retroreflective Microfacet (MRM) model, which turns any existing microfacet BSDF into a physically plausible retroreflective one by a single substitution: replacing the view direction with its reflection about the surface normal before evaluating the standard model. Based on the previously published back-vector formulation, MRM requires only minimal code changes and has been adopted in the OpenPBR and MaterialX material standards. We prove reciprocity and energy conservation under the assumption of a reflection-symmetric normal distribution function (NDF), which holds for all commonly used distributions, and validate the model against measured retroreflective material data.

cs.GR↗

arXiv2017

The Iray Light Transport Simulation and Rendering System

While ray tracing has become increasingly common and path tracing is well understood by now, a major challenge lies in crafting an easy-to-use and efficient system implementing these technologies. Following a purely physically-based paradigm while still allowing for artistic workflows, the Iray light transport simulation and rendering system allows for rendering complex scenes by the push of a button and thus makes accurate light transport simulation widely available. In this document we discuss the challenges and implementation choices that follow from our primary design decisions, demonstrating that such a rendering system can be made a practical, scalable, and efficient real-world application that has been adopted by various companies across many fields and is in use by many industry professionals today.

cs.GR↗