HdRestir 4 — Renderer Performance Metrics
Render time alone does not explain whether an estimator is improving. A faster frame may trace fewer useful paths; a cleaner image may simply spend more rays. HdRestir therefore measures work, noise, error, and time together.
This chapter defines the instrumentation used throughout the project: samples, rays, variance, RMSE against independent references, hierarchical timing, and time-to-quality comparisons that remain meaningful across CPU, GPU, Path Tracer, and ReSTIR pipelines.
