Certain textures seem to be covered in a weird square “mesh”. Using temporal AA fixes it, but it brings a lot of other graphical issues related to it being… well, temporal AA. Here’s an example taken in my condo.
What you are looking at is AO being blended with anti-aliasing.
Temporal AA is not something we developed. It is part of Unreal 4. Any graphical glitches with it will have to be fixed by upgrading the engine (maybe there is a fix for this issue). However, this could just be a limitation of their graphics implementation.
Sorry for responding this late. I didn’t notice your response.
Anyway, if I might ask, how comes the mesh stays even if one disables the AA? And is it somehow fixable?