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Skylight issue

Hi !

I hope you can help me, I have a problem with my skylight… It “illuminates” two meshes in my scene and I don’t know why. I tried to switch the skylight between static and stationnary, I checked if I had some holes in my wall/ceiling/ground, I checked the lightmap and I checked my mesh. Nothing. And the strangest is that I have the same mesh in another places in my scene and they’re not affected by this problem.

Some screenshots to understand the problem:

Screen 1
Screen 2
Screen 3

Thank you !

This resembles a problem I got when I had forgotten to create lightmap UVs for the meshes. Do they have lightmap UVs?

Yes, they have lightmap UVs and they’re good. I have no problem with this same mesh in another place in the scene… I built the light in production mode and now, it looks like there is a spotlight on my doors…

http://image.noelshack.com/fichiers/2016/29/1469000871-highresscreenshot00003.png

Could also be reflection probes causing that I suppose, they should be large enough to encompass the entire door. But without seeing the scene it could be other random factors.

We checked the reflection probes and apparently, that’s not the problem…

Some screens:

http://image.noelshack.com/fichiers/2016/29/1469002718-highresscreenshot00004.png

http://image.noelshack.com/fichiers/2016/29/1469002718-highresscreenshot00006.png

http://image.noelshack.com/fichiers/2016/29/1469002717-highresscreenshot00005.png

http://image.noelshack.com/fichiers/2016/29/1469002732-skylight.jpg

http://image.noelshack.com/fichiers/2016/29/1469002732-uvs2.jpg

are the doors set to movable? b/c I think its light cache, or how unreal lights movable objects with light baked caches. Check Show>Visualize>VolumeLightSamples

Hi daveSchoneveld, thank you for the answer.

The doors are static. Here, the screenshot with VolumeLightSamples on:

http://image.noelshack.com/fichiers/2016/29/1469090369-highresscreenshot00007.png

We don’t see the problem but it’s still here… I just bake my doors on another level. We can see the issue when I put my skylight on stationary…

http://image.noelshack.com/fichiers/2016/29/1469090370-highresscreenshot00008.png

Stupid thing to try maybe, but what happens if you move the doors and black objects just a bit to fully invalidate lighting, move them back and then rebake? Also, what I always do for environments like this to prevent any weird light bleeding issues is build a box around it that merges with the holes for the windows. This usually prevents any sort of strange lighting from the exterior affecting the interior.

My skylight gives different reflection results when switching between Stationary and Movable too.

A quick fix is to check the “light as static” but then when you open the doors the light on the doors will not change.

I do think its those volume samples. I would experiment with ways to get the volume samples higher at the door area (LightmassCharacterIndirectDetailVolumes), higher in samples and higher in Z, b/c I think the samples are fading out at the top of the doors.

@Maximum-Dev, I think the skylight on stationary mode takes every baked data that has been computed in the level at some point into account, even if its outdated. Thus it makes sense that the reflections look different since there might be some old occlusion data available. When its dynamic though and no DF data is available, its just the pure un-shadowed thing.

It could also be that it gets applied in different passes depending on which mode is enabled and thus there is a different look to it if you dont bake the stationary one. If you want everything to be fully dynamic, the movable one is as accurate as it can be without localized occlusion data from lightmass.