I’v found on internet that sometimes it is not enough to simply unwrap model, and make sure that there are no overlapping UV islands. We also must be sure that “UV is not flipped”. Meaning: Normals of all UV-islands must be pointed up or outward, towards user face.
I know that in Maya they have tool which highlight flipped UV-islands.
Here is how they do it
Do we have something like that in Blender?
P.S. Never heard that UV which normals point downward is an issue, since all renders and game engines understand this kind of UV correctly.
UPD: Or may be, saying “UVs are facing in correct postiton” she just meant that we simply need flip UV-island horisontally (or vertically if necessary) and that is all? It would make much more sense. I’m not a native speaker so when i hear “facing” i imagine that we talk about proper direction of polygone normal.