Hello,
I extracted this model from a Unity game and I have a weird problem where the wheel gets darker as it rotates.
I suspect it might be a normal map issue, but I’m unable to identify what causes the problem. The only “tricks” I’m aware of are of the type of normal map (here, it’s OpenGL) and choosing a “non-color” data type.
Here is a link to the blend file : https://drive.proton.me/urls/M5A96TKPXM#l4rwHyf4nuTt
Thanks in advance !
Hey !
It seems that the N_Alpha that is linked to the strengt of the map is causing issues :
When unlinking the Alpha and setting the value to 0(because is is inverted in the node group) it fixes the issue.
Whene you encounter issues link this, juste linking ang unlinking textures and testing can help troubleshooting.
Hope it helps !
There seems to be an issue with the normal map (APC_Details_N.png).
It’s not there, I think. I can’t view it at all.
Hi, your method works, but it also means disabling the normal map ? 
When I connected the textures, I assumed the alpha channel was the normal strength since it was part of the same texture. But I don’t know how Unity shaders work, so I’m not sure.
I found a post talking about swapping some color channels, I tried it but I still get the same problem. Red Normal Map?
Hello, you’re right, I didn’t notice. I re-added the texture and re-packed the file.
I had the same problem for a vehicle from an another, but it disappeared when I noticed I forgot to set the color space to “non-color”. Here the normal map is already set to “non-color” but the problem persists.
The file is no longer available, but what does your normal map look like across the four channels (RGBA)?
Here is the normal map. The red channel looks different from the others. I tried using the alpha instead of the red channel, but I still have the same problem.
Idk why the link doesn’t work anymore, here’s a new one : https://drive.proton.me/urls/1G1VJTAAAG#nWDy5sVcNkyC
That seems to work, thanks !
How did you know this was the problem ?
If you understand the logic behind a normal map, it’s pretty easy.
In a normal map, R and G contain angles, and B is the complementary normal length.
In your image, R and B are swapped.
