Lightmass Importance Volumes

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1

Would it be more beneficial to have multiple small lightmass volumes versus one big one to cover the whole level? I am having issues when I rebuild lighting that is starting to confuse me. Light in rooms where there are no lights or windows to give light. I have a Sky Sphere in the level using a Directional Light as the sunlight control for direction of the sun. I am also using a SkyLight to help eliminate some of the shadows in the darker areas so that things look like they would in the real world when a shadow is behind a tree you can still see what is behind it just not as bright as everything around it. Room that should be having light in them via a window don’t have light at all. When a light comes in a window it should illuminate that part yes but it should also give a bit of light to the room since it is a light source.

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The first image is in the editor and as you can see there are no light nodes anywhere in there. The second image is when I am actually in game and as you can see there are no lighting resolve issues that need address as I rebuild light every play it feels like. THere should be little to no light in this room especially in the back near the pillars. Am I missing something here with Directional lights and Sky Lights? Or is it because of the single LIghtmass Importance Volume.

2

Is your skylight set to static?

3

It was set to stationary. Set it to static and rebuilt lightning, and that did the trick. Thank you for pointing that out.

4

You can have as many small ones as you want, but it’ll make no difference. At build time, Unreal will just make a single large one that encapsulates them all regardless. The end result is the same, just use a larger single volume and save yourself the trouble.

5

I’m gathering information about this topic. It sounds like multiple smaller ones would still be beneficial?

From the docs: https://docs.unrealengine.com/en-us/…ghtmass/Basics

“If you place multiple Lightmass Importance Volumes, most of the lighting work will be done with a bounding box that contains all of them. However, Volume Lighting Samples are only placed inside the smaller volumes.”

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