Lightmaps
Lightmaps add precomputed surface illumination to luma.gl materials. They are useful for static indirect lighting whose cost has already been paid by an offline bake. They use authored UVs and texture data rather than computing light transport at runtime.
Example​
The authored Lightmapped Cornell Box demonstrates the existing material path. The example's Attributions tab identifies its source; the importer preserves the source material and UV data.
Material parameters​
lightmapIntensity is a nonnegative multiplier with a default of 1. The linear RGB lightmap
is supplied through pbr_lightmapSampler. Set HAS_LIGHTMAP: true on the compatible model and
set lightmapMapEnabled: true, and provide lightmapUVSet and lightmapUVTransform. A material factor alone does not bind a texture.
The lightmap supplies precomputed illumination; it does not create dynamic shadows or update when lights or geometry move. Keep the bake's lighting assumptions consistent with additional scene lights to avoid counting the same illumination twice.
See texture coordinates and transforms, environment lighting, and glTF lightmap conversion for source mapping and support limits.