GI hits: skip point-shadow rays for lights that contribute little #983

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opened 2026-10-23 18:07:42 +00:00 by sky_line · 1 comment

sky_line commented

2026-10-23 18:07:42 +00:00

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Point shadows at GI hits (K=1) cost up to about 0.66 shadow rays per pixel. Skip the ray when the light's share of the hit's total is small (e.g. under 10%). About 0.3-0.7 ms, with bounded error. Small effort.

From the 2026-10-23 GI performance pass. Baseline: RTX 5090, 4K, DLSS Ultra Performance (1280x720 render), GI at full render resolution, GI 3 + cache, ReSTIR DI 3, emissive on: GPU 30.9 ms/frame (GPU-bound), async deferred lighting 20.1 ms, `c_gi_trace` 12.7 ms (883k rays/frame). Point shadows at GI hits (K=1) cost up to about 0.66 shadow rays per pixel. Skip the ray when the light's share of the hit's total is small (e.g. under 10%). About 0.3-0.7 ms, with bounded error. Small effort.

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sky_line added this to the Slipstream project

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sky_line referenced this issue

2026-10-25 03:19:37 +00:00

[Epic] Shared ray-traced visibility pass (ray queue) for shadows, GI, reflections and lit shaders #1039

sky_line commented

2026-10-25 03:19:37 +00:00