With materials in Godot do normal maps need to have the green channel flipped

AI_Messiah

Anyway some of the graphics specifications use different approaches to normal maps than others

TwistedTwigleg

In some graphics APIs the green channel is up, while in others it is down, so that is why it sometimes needs to be flipped. I think OpenGL and Vulkan are green up, while DirectX is green down (could be wrong- this is just off the top of my head). If you are using normal maps authored for DirectX in Godot, then you’ll need to flip them.

Calinou

It depends on your source normal map. Try importing the normal map and see if it's the right way around. If it's not, select the normal map texture in the FileSystem dock, go to the Import dock, enable Normal Map Invert Y and click Reimport.

Note that the above import option is only available in Godot 3.4 and later.