restirDirect

The render feature that runs resampled direct lighting.

Four compute passes in afterLighting (orders 80-83) and a composite at 84: candidates and temporal reuse over a cell grid, spatial reuse between cells, per-pixel shading of the source each cell settled on, then a cell-aware average of that light onto the frame.

It starts and stops with the source registry in @builtin::systems.restirLighting.restirLighting, which is also where the settings live.