GI resolution under DLSS: checkerboard tracing or half resolution instead of every pixel #979

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opened 2026-10-23 18:07:41 +00:00 by sky_line · 0 comments

sky_line commented

2026-10-23 18:07:41 +00:00

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RenderVKDlssFullResSignals forces GI to the full render resolution under DLSS, so every pixel traces (883k rays at 720p).

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RenderVKGITraceEvery 2 (checkerboard): half the fresh rays and hit shading. About -4 to -5 ms. GI stays raw-routed to Ray Reconstruction, with slightly noisier, laggier input.
GI scale 0.5: about -9 ms. Without RenderVKDlssRawSignals bit 32, GI falls back to our denoiser plus upsample (+~0.5 ms), and edges on thin geometry get noisier (the reason full-res was made automatic). With bit 32, RR gets 2x2-correlated noise.

Decision needed on the default. Suggested first try: the checkerboard.

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). `RenderVKDlssFullResSignals` forces GI to the full render resolution under DLSS, so every pixel traces (883k rays at 720p). ## Options - **`RenderVKGITraceEvery 2` (checkerboard):** half the fresh rays and hit shading. About -4 to -5 ms. GI stays raw-routed to Ray Reconstruction, with slightly noisier, laggier input. - **GI scale 0.5:** about -9 ms. Without `RenderVKDlssRawSignals` bit 32, GI falls back to our denoiser plus upsample (+~0.5 ms), and edges on thin geometry get noisier (the reason full-res was made automatic). With bit 32, RR gets 2x2-correlated noise. Decision needed on the default. Suggested first try: the checkerboard.

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2026-10-23 18:07:41 +00:00

sky_line added this to the Slipstream project

2026-10-23 18:07:41 +00:00

sky_line self-assigned this

2026-10-26 02:58:24 +00:00