Substance Painter 2018.2.1 - .tga normal map export artifacts

IDCrisis0

Hey all,

I know I'm probably just missing something obvious here, but I'm getting some artifacts in my normal map when I export as 8bit .tga or .png. In the past I haven't had this problem, and I need the .tga for UE4. I've tried a 16bit .png and the artifacts are not showing up. Has anyone else run into this issue?

Note: I have tried with the "Compute tangent space per fragment" enabled and disabled with the same results.

8bit .tga file exported from Substance Painter / 16bit .png exported from Substance Painter


Export options window - 8 bit .tga 

Any help is much appreciated.

oblomov

It's a typical quantization issue. For such a smooth surface, you would need either to add edge loops to get rid of the smooth gradient on the flat side of the sword, or use a 16bpc normal map, or add dithering on the normal map. See https://polycount.com/discussion/148303/of-bit-depths-banding-and-normal-maps

IDCrisis0

Thanks, @oblomov that's exactly what I was looking for! Looks like adding dithering is what I'll need.