Strange Glitch

[Echohalls]

Hey guys, I was running a test map and I came across this bizarre glitch

This triangle shadow thing has been annoying the living hell out of me and I see it through out the whole map.
I have zero ideas where this is coming from.

[daortir]

Do you have big spotlights in your map ? I had this once and it happened because of some huge spotlights. No idea why, but as soon as I removed one of the spotlights it stopped happening.

[Echohalls]

I currently have one large spotlight to simulate sunlight

That might be the issue

[Red]

Yes, same problem here, the spotlight, do not make it too long by radius.

[Echohalls]

I think I fixed it now. Thanks for your help.

[FlawlessHappiness]

If this problem occurs again, and it's not the spotlight, then it can also be encountered by a too large boxlight