Physically-based rendering

A Free-Space Diffraction BSDF

Free-space diffractions are an optical phenomenon where light appears to "bend" around the geometric edges and corners of scene objects. In this paper we present an efficient method to simulate such effects. We derive an edge-based formulation of …

Path tracing in Production: The Path of Water

Microfacet theory for non-uniform heightfields

We propose new methods for combining NDFs in microfacet theory, enabling a wider range of surface statistics. The new BSDFs that follow allow for independent adjustment of appearance at grazing angles, and can't be represented by linear blends of …

Random-Access Neural Compression of Material Textures

The continuous advancement of photorealism in rendering is accompanied by a growth in texture data and, consequently, increasing storage and memory demands. To address this issue, we propose a novel neural compression technique specifically designed …

Physically Based Rendering: From Theory to Implementation, 4th Ed.

A Position-Free Path Integral for Homogeneous Slabs and Multiple Scattering on Smith Microfacets

We consider the problem of multiple scattering on Smith microfacets. This problem is equivalent to computing volumetric light transport in a homogeneous slab. Although the symmetry of the slab allows for significant simplification, fully analytic …

Practical Aspects of Spectral Data in Digital Content Production

Real-Time Path Tracing and Beyond

Real-time graphics is on the cusp of a historic transition to path tracing. With recent advances in hardware ray tracing, systems research, stochastic light sampling, and denoising, we show that complex light transport effects can be path traced in …

Unbiased and consistent rendering using biased estimators

We introduce a general framework for transforming biased estimators into unbiased and consistent estimators for the same quantity. We show how several existing unbiased and consistent estimation strategies in rendering are special cases of this …

Research Advances Toward Real-Time Path Tracing

Real-time graphics is on the cusp of a historic transition to path tracing, one of the largest breakthroughs for real-time graphics in many years. Path tracing is the most accurate way of rendering but is also computationally intensive due to the …