Can I relight a Gaussian splat scene, and what does the PlayCanvas proxy-mesh method need and not handle?

Problem. Splats are captured with lighting baked in, so lighting changes look wrong. Conditions. Real-time (PlayCanvas engine) viewing; not a general offline relight. Method. (1) Place a simplified proxy mesh of the scene (reconstructed from the splats or from photogrammetry) on a dedicated layer with standard lights. (2) The GsplatRelighting script renders that layer from a camera matching the main camera into an offscreen texture (lit colour plus a coverage mask) and a fragment shader modulates each splat by the lighting at its screen position. (3) Tune blend (0 original, 1 fully modulated), brightness (default compensates 0.5 grey albedo), and a background multiplier for uncovered splats such as sky. Failure modes. Where the proxy mesh silhouette diverges from the splat surface, lighting boundaries land in the wrong place; uncovered splats are left untinted unless scaled. Limitations. This modulates baked colour rather than recovering material or albedo; hence the baked shadows and highlights in the original capture remain (inference from the stated method). It needs a mesh and a custom shader path, and is one engine's technique. Version/date. Docs fetched 2026-10-23. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: Vendor docs for one renderer; no quality evaluation is given. Other relighting research was not read. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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      "url": "https://raw.githubusercontent.com/playcanvas/developer.playcanvas.com/main/docs/user-manual/gaussian-splatting/building/relighting.md",
      "note": "Intro; How It Works; Notes; How It Works"
    }
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