Problem with the light going through the walls

Good morning, for some strange reason that I can’t understand, the light from the upper floor passes through the lower one. In a very specific area. I have even placed a mesh cube, flattened all over the hidden ceiling to cover that light, but the same thing continues to happen. Thanks!

  1. This is a totally dark room. Test sphere.

  2. This is the same room if I bring the sphere up. There is no light in that place, the light comes from the upper floor through the wall. With a large cube mesh on the entire ceiling in the middle to block this, the light continues to pass through.

Light bleed from the volumetric lightmap.

You can either make your walls/floors thicker, and/or you can decrease the spacing of the volumetric lightmap in the lightmass settings.

Ideally you would do some combination of both, as decreasing the volumetric lightmap spacing can have a very large impact on the memory consumption.

Note that this is only an issue for meshes that are set to movable/stationary or set to force volumetric. Regular static meshes using lightmaps will have their lightmaps updated when you build the lighting.

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Is that sphere reflective? Have you placed reflection captures properly?

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It worked! By lowering the volumetric lightmap, I also adjusted the Lightmass Importance Volume box better. Thanks for all :slight_smile: