How to avoid inverted Normal maps

Community Community & Industry Discussion
1

I used the same normal map I had previously made with Blender and used in Unity 3D too. But when I used it in UE4 the normal map got inverted: what was supposed to be concave now is convex.

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Any ideas?

Thanks guys :slight_smile:

DPC

2

Open the texture file (double click it) and flip the green channel.

3

Your normal map is not imported correctly. When you import a normal map you need to make sure it is using normal map compression which you can check that the map is a normal map in the import options. You can also add to the file name “_normal” and it will import it automatically as a normal map.

4

Thanks Bruno Xavier.
So I guess this is a common practice in UE4 ?

For those newbies like me, and to remind myself in case I need to:
You achieve that by double-clicking the normal map texture, opening this way the Texture Editor. There under the Texture section, click on the little triangle/arrow pointing down to extend that section so you can see the “Flip Green Channel” checkmark. Click Save on the upper left corner, Done.

5

Also when you create your normal maps, just switch the green channel swizzle when you bake and you’ll never have to deal with it again =]

6

Thanks Xerithas :slight_smile: