ZDoom

I noticed that when Vulkan is enabled, the textures (floor/ceiling/wall) flicker between normal and all black, depending on the viewing angle. This only happens with Vulkan enabled; OpenGL doesn't behave like this. I've encountered this both with Umbra of Fate and (to a lesser degree), Freaky Panties and Shadows of The Nightmare Realm. I also noticed this in 4.0 in Freaky Panties (UoF wouldn't start in 4.0, so I have no idea if it happened with that one).

UoF is by far the worse. I have a video showing what's happening here.



i7-2700K 3.4 GHz
12GB RAM
GeForce 1080
Slackware Linux 14.2, 64-bit
nvidia driver 418.56

The lighting in that map is entirely done with point lights, so there's a lot of them.

I've seen this in some of my maps that have heavy dynamic light only lighting, too. Surfaces just lose all lighting depending on the angle and position of the player.

I'm not 100% sure, but I think this commit fixed this issue.

Seems like that did the trick for me.