Normal Map Acting Weird

Development Rendering
1

Hello all,

I have this little interior scene I’m working on. The problem is, if I apply a normal map to my columns, their shading gets all messed up.

UE4.PNG

I tested the exact same mesh and normal map in Unity and Blender as well, no problems in either of those. Same with Substance Painter. In fact, the normal map is a SP default.

U5.PNG
UE4.PNG

I have probably checked and unchecked every option I could find in Mesh and Material editors, to no avail. Tested with both static and dynamic lighting as well. Same with smooth and flat shading, no result.

The column itself is a simple cube mesh that I first scaled up in Z and added bevel and loop cuts to later on. I actually made this scene two times so far. First time the columns had to back faces, as they wouldn’t be rendered anyway. Thought that could be the problem, The ones in the pictures have their back faces intact.

I get no errors when importing them into UE4. I think it’s the bright columns that are getting lit up, rather than the dark ones getting shadowed.

Any ideas?

2

-have you set the texture mode from your texture and the texture sample to “normal”
-what happens when you flip the green channel -> in the texture editor window (details panel) :slight_smile:

3

Oh, you’re absolutely right! I just assumed UE had imported it as a normal map at first. Thanks a lot!

Such a small oversight on my part and I almost remade the entire scene… :smiley:

4

If you suffix your normal maps with “_N” or “_Normal” it should automatically recognize them as normal maps (It just asks for confirmation).

5

actually the engine uses the texture data to try to figure it out. I am not sure the exact method used but it has something to do with testing a bunch of points and seeing if they are closed to normalized. So if your normal map had a black background instead of a blue one or it wasn’t normalized for some reason the engine might miss it.