Difference between Static, Stationary, and Moveable skyights

So I am reading this article ( to better understand why there I experienced a difference switching my skylight from static to moveable today, and I would really like it if someone could…uh…dumb it down a bit. Break it down semper-gumby style, if you will.

So what I experienced:
My room was very dark on the inside, but it was nice and sunny outside. I fiddled around with a map that came with an asset pack I bought, and I eventually noticed that his skylight and directional light (sun) were set to moveable (mine were both set to static). Now I read somewhere yesterday (I can’t remember where) that if you have a good sized landscape then you should set your light source and skylight to moveable. Since the asset map I was playing around with did it (and his results were nice) and read it online (so it must be true sarcasm), I did the same; and boy was there a difference. My indoors were all nicely lit up…I could actually see inside my rooms…and I have no idea why. Also, would there be any difference if I were to switch it to stationary (this post (skylight movable and stationary - Unreal Engine Forums) says that moveable doesn’t create realistic shadows yet stationary does).

Oh, and thank you to anyone who has the patience to deal with my dumb butt :slight_smile: You are the real heroes


I think you should read more and understand lights in Unreal!
The main difference is that movable lights don’t produce GI!! Static lights can’t change at all in gameplay, stationary can have small changes (like color)… Static lights are “free” (they are pre calculated maps), movable is the most “expensive”…