ReSTIR

Area ReSTIR: Resampling for Real-Time Defocus and Antialiasing

Recent advancements in spatiotemporal reservoir resampling (ReSTIR) leverage sample reuse from neighbors to efficiently evaluate the path integral. Like rasterization, ReSTIR methods implicitly assume a pinhole camera and evaluate the light arriving …

Decorrelating ReSTIR Samplers via MCMC Mutations

Monte Carlo rendering algorithms often utilize correlations between pixels to improve efficiency and enhance image quality. For real-time applications in particular, repeated reservoir resampling offers a powerful framework to reuse samples both …

Amortizing Samples in Physics-Based Inverse Rendering using ReSTIR

Recently, great progress has been made in physics-based differentiable rendering. Existing differentiable rendering techniques typically focus on static scenes, but during inverse rendering---a key application for differentiable rendering---the scene …

Conditional Resampled Importance Sampling and ReSTIR

Recent work on generalized resampled importance sampling (GRIS) enables importance-sampled Monte Carlo integration with random variable weights replacing the usual division by probability density. This enables very flexible spatiotemporal sample …

A Gentle Introduction to ReSTIR: Path Reuse in Real-time

A course gently introducing the basics of Monte Carlo integration, resampling, RIS, ReSTIR, and rendering applications of ReSTIR.

Generalized Resampled Importance Sampling: Foundations of ReSTIR

As scenes become ever more complex and real-time applications embrace ray tracing, path sampling algorithms that maximize quality at low sample counts become vital. Recent resampling algorithms building on Talbot et al.’s [2005] resampled importance …

Fast Volume Rendering with Spatiotemporal Reservoir Resampling

Volume rendering under complex, dynamic lighting is challenging, especially if targeting real-time. To address this challenge, we extend a recent direct illumination sampling technique, spatiotemporal reservoir resampling, to multi-dimensional path …

Rendering Many Lights with Grid-Based Reservoirs

Efficient rendering of scenes with many lights is a longstanding problem in graphics. Sampling a light to shade from the pool of all lights, e.g., using next event estimation, is a nontrivial task. Sampling must be computationally efficient, must …

Rearchitecting Spatiotemporal Resampling for Production

Recent work by Bitterli et al. introduced a real-time, many-light algorithm for rendering dynamic direct illumination from millions of lights by iteratively applying resampled importance sampling using weighted reservoir sampling. While enabling new …

ReSTIR GI: Path Resampling for Real-Time Path Tracing

Even with the advent of hardware-accelerated ray tracing in modern GPUs, only a small number of rays can be traced at each pixel in real-time applications. This presents a significant challenge for path tracing, even when augmented with state-of-the …