normal map seams

[ברק5F9C]

Hello everyone, I'm new here. Currently, I'm working on creating my first stylized low-poly (game-ready) model. When baking high to low-poly in Substance Painter, everything looks good with  all mesh maps and material view. However the normal map (mesh map)  has visible seam lines.

After searching online, I found a few potential solutions to this problem:

I've already tried raising the bake resolution, but it's already at 8k.

I made sure that my UV islands have 32 pixels padding between them when Substance Painter's dilation is set to 32, so they should not be affected by each other.

I attempted painting the seams of the normal map with the average color of the normal map, which did make the seams disappear, but it caused imprecise results around the seam areas and even were noticble in matirial view.

I haven't attempted aligning the UV island seams with the UV grid, as I need to optimize the model for gaming, and aligning might cause issues with UV packing.

does anyone have suggestions how to fix this issue? or is it even importent to fix the normal map seams if they dont show up in matirial view ?  Thank you!

[Cyril Dellenbach · Accepted solution]

Hi @ברק5F9C,

Thanks for the question.

As you mentioned, a visible seam in your normal view isn't a problem as long as you don't see it in your material view. It is pretty common to have normal seams, and this is due to the UV shells rotation. To make it simple, as the normals work in a tangent space, the purple (for example) will always comes from top to bottom (in DirectX format), regardless of the UV orientation. Therefore, if you paint something in between two UV shells, this may create a seam on the Normal map depending how the UVs are rotated.

In fact, these seams on the Normal map prevent seams on your Material. So don't worry, this is the expected behavior, and as long as you don't have an issue with how your material look, there are no problems.

Best regards,

[ברק5F9C]

thank you for your detailed response and providing clarification !