Lighting disappears when built

Here is a video of the problem

I tried to make a floor static mesh out of a BSP and it worked for a while but then I rebuilt lighting and this problem started happening. I’ve tried fiddling with all the settings on the light and this bug persisted. Very new to UE4, thanks for any help!

Hi, so what exactly is your goal here? Are you testing out the lighting, or do you have a specific setup in mind?

  • If you want to Bake the light completely just set it as Static.
  • Stationary lights are “stationary”, yet you can modify there values and it should bake some bounce light into the scene.
  • If you want a Dynamic light that changes position set it to move (this disables all baking for this light though).
  • If you want some fill light for this dark scene, place a skylight and set a low value.
  • Did you check if the the Box object is set to static? If it is set to movable it will not bake any lighting information.

Building light is only really reserved for “Lightmass Global Illumination” and high quality static shadows.

link to the documentation CPU Lightmass Global Illumination | Unreal Engine Documentation

If you don’t need to bake GI, then don’t worry about building the light.