A scene I’ve been working on for a while had its Skylight suddenly broken. It’s as if the Skylight had always 0 intensity and essentially not affecting the world at all. No matter whether I increase its Intensity, change its color, it just doesn’t seem to affect the world anymore. The light is indeed set to Affect World, but this doesn’t seem to be doing anything anymore.
I didn’t really touch any other settings related to this, it just seemed to happen randomly. I have another scene where I have a working Skylight and this one works without any issues. I even tried copying that working Skylight to the other scene but didn’t change anything.
Is there perhaps a setting related to the level that I could tweak or reset somehow to get the expected effect from the Skylight?
I managed to solve it with the help of a colleague.
What we infer happened was that whenever you make a new level, there is precalculated information that is immediately associated with a SkyLight when you place it. And this information can change as you build the level but will not affect the SkyLight unless you manually recapture the scene.
The problem I had must’ve been that the SkyLight, for whatever reason, tried to recapture the scene by itself (probably some other process trigger this recapture), and when it didn’t find anything suitable to build the skyLight with, it just defaulted to black. This problem can also be seen in the Lightmass properties in the world Settings, where most of the Lightmaps are completely black.
The way I solved it was simply creating a 2-sided material and added it to a sphere that would envelop the whole level. After that, Recapturing the scene effectively fixed the problem, Lightmaps now had information and shadows in the level were no longer pitch black.
Additionally, the Sky Distance Threshold of the SkyLight might help as well. Setting it to lower values will make it more likely for the SkyLight to pick up on objects in the level, ensure the SkyLight is actually taking information in.
TL;DR: Levels have a prebuilt capture for SkyLights. If you come across this problem, try either Lowering the Sky Distance Threshold of the SkyLight, or enveloping the whole scene in a sphere that has it’s normals inverted and then hitting the Recapture button in the SkyLight.
I was having an apparently networking-related version of this problem, where my skylight was totally black when joining a game as a client. I solved the problem by recapturing the skylight during the beginplay event in blueprint.