Hey there,
I created a new project to mess around with the lighting settings. However, my simple cube has issues on the edges:
Sometimes it’s shadows that leak, sometimes it’s light. Haven’t had a error-free build yet.
Here’s the current setup, the mesh itself is extremely simple:
It’s supposed to represent a simple room. Walls, a window etc.
Here’s the lightmap:
And the settings:
- The lightmap resolution is unreasonably high at 1024
- Tried “Double Sided Geometry,” “Two Sided” and “Shadow Two Sided” individually as well as in combination
- Tried with both static and stationary lights/cube
- Adjusted Shadow Bias settings for the lights
- Tried a setup with a directional light and meshes around the cube to block the light
- I’m using the default Lightmass .ini file, no changes there
- All builds have been set to Production
- The mesh is literally the default cube in Blender with a hole in it. No smooth shading, no bevels, no overlapping vertices
- Didn’t change any project settings, made an entirely new project to test things out
- The material is extremely simple as well, it only has data for Base Color
- Using UE 4.14.1 on Win10
Wanted to make sure my settings would work before building the lights for a much larger scene. But, I’m having trouble with what is literally the simplest level ever. 
Searched the forums a bit, tested everything I came across, I just can’t get a proper light build.
So yeah, any idea how I can fix this? Thanks.
4.14.1