LUMEN, why inside a closed room I can even see lighting instead that darkness?

I’ve create a room with 4 walls , floor and ceiling, room is completely closed but I still see lighting, why?

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any suggestion?

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I have the same problem but only if I have two closed rooms that are connected through a doorway and I look inside the other room.
Sorry that I couldn’t help directly.

Thin walls+Distancefields dont play well together

I had a similar problem and it turned out my floor was too large (it was a huge rescaled cube) and wasn’t being added to the global distance field, so there was a huge hole in the ground where light was coming in.

You should also ensure that if you are using exponential height fog, that you have enabled volumetric fog, as fog cannot be shadowed unless it is volumetric.

With Lumen you should not use a simple plane (even with 2-sided mat) or box with tiny width (less then ~10 cm) as a walls cos this will lead to light leaking

Left wall from cube with enough width:

Left wall from cube with tiny width:

Left wall from plane with 2-sided mat:



I’m using cubes with right thickness but the problem is stills on

Volumetric fog is on and not shadowed. Sure this may affec lighting inside a cube? I’m working on Skylight, postprocess and directlight but nothing

Do you have a “Generate mesh distance fields” option enabled in Project settings? Lumen relies on this one heavily.
Also you can go to Show → Visualize → Lumen Scene to confirm that there are anything for Lumen to work with

Yes I double check everything, both Lumen and distance field.
The problem disappears if I turn OFF the skylight but, it doesn’t make any sense. So there is a bad relationship between skylight and lumen but it shouldn’t be!