Author Topic: Flipped normals on some parts  (Read 375 times)


 Got some weird issue with Normal Maps. On some part of my model they are flipped. I checked my mesh if - everything is ok with normals (both faces and vertex). My UV has proper layout, nothing flipped. I tried different settings in the Bake options. Always is the same thing

 Now the biggest test I made. I baked my normals with Xnormal and everything is fine there. So it seems that my models are ok. There is a problem with my settings or with the baker itself.

Any idea what is going on?

Here are screenshots how it looks like. The wrond ones are from Painter, the good from Xnormal:


Does it look ok in the viewport when you apply the texture as an actual normal map, or is there a seam visible? This kind of seam that you see when you apply the normal map as color map is not necessarily a problem.

What normal map format do you use in Painter? You can switch the format in Edit -> Project Configuration to DirectX or OpenGL.

Have you tried to just invert the green channel in the map itself?

 I put the normal map on a layer with normal and it is the same thing. The seam is not an issue. The problem is that I got flipper normals and when moving my lights around I can see that something is wrong.

 I am using Unreal Engine 4 so my settings are DirectX and "Compute tangent space per fragment". I did export my model with "Triangulate" and "Smooth group" from Maya 2018.

 Another strange thing is that some parts are ok - like I show this in the link below. This is one mesh but 2 separate uv island. So the seam is ok but I don`t know why it is baked flipped on the same UV island AND on the same mesh. Few parts are ok and you can see that it is the same side but most of the second uv has flipped colors.

 Flipping green channel will flip my entire map. Thats the problem. This is one mesh, one map but 2 uvs. I can`t flip the whole thing.


Can you share the model, or some part of the model where the flipping is happening so I can have a look? OBJ format or FBX.