Lightmap Artifacts on large mesh WTF!!????

Hello once again,

I’ve been working on this for DAYS and tried SO MANY things to only get the EXACT same result. Changing one thing that i thought would fix it to only see the same sh*t.
Anyway…
As you can see i’m getting some crazy light bleeding or some sort. The weird thing is ive tried everything and changed so many things to only get the same result. With the same bleed error in the same place. Just increasing the lightmap res just makes it more prominent

I’ve tried:

  • increasing the lightmap to 4096!
  • Separating every face
  • making sure i have enough space between uvs
  • unchecked generate uv’s (Even re importing and unchecking it that way)
  • Separated my walls into smaller pieces.
  • Snapping UV’s to grid (Also making sure grid size is equal to ue4 units ((1 divided by 512))
  • Making sure i know the differences between Lightmap Index vs Destination Lightmap and all the other lightmap settings

I’ve literally tried everything and now i think i should just re do the mesh but after spending so long on it i feel like ive wasted my time!!
Especially if i re do the whole mesh and get the same results!! I want to know whats causing this so if i get it again i know what to do.

Please help.

I’ve also just added a block behind the walls with a black material which usually stops light bleeding but still getting the same result :’(

Also im wasting a lot of time waiting for the bakes to complete to only then be disappointed again. Is their a better way i can preview my bakes without actually baking?

I figured it out. I was looking too much into it, as usual. My box reflection captures needed adjusting. I did more research on the ‘Box Transition Distance’ scroller and found out that my walls needed to be inside the inner box.