Author Topic: Seams on Mirrored UVs - Maya Export Substance Bake  (Read 5375 times)

I'm encountering seams on this bake, I tried a number of different ways to get rid of the seam without adding smoothing groups (as Mikkt should not require them if I remember correctly) and also adding a hard edge around the area where I'm getting the Mirror UV Seam does not help. Here are screenshots of the issue, the geometry and UVs are pretty simple.

Images of Settings and Seam: http://imgur.com/a/kC1n7


Also just tried using a cage mesh exported from Maya and the seam was still there.

Hey akaikami,

are your mirrored UVs moved to the next UV space? Make sure the UVs are moved exactly one UV set to the side.


Best Regards
Environment Artist - Twitter

Yes, they are. If you check out the images I've posted you'll see all the settings I've got and how my geometry is setup.

Can you check that the binormals/tangent are split on your symmetry axis ? (Menu Display > Polygons > Tangents)
Also if I remember correctly Maya 2014 has an issue in it's FBx exporter where Tangent and Binormals are not exported properly. This was fixed in maya 2015 only.
Don't forget your log file. It can be exported from the Help menu of the software.
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Fabrice Piquet aka Froyok. Product Manager, Technical Artist and Documentation at Adobe.

I've also added hard edges on the symmetry line however I thought the point of Mikkt was to not use hard edges at all? And let the baker/engine determine the tangents of the geometry.

Even added the hard edges in the symmetry line and exporting tangents and binormals from Maya I still get a seam. Does anybody here have 2015 and be able to try it out? We only have 2014 at work currently.

Here are the source files: https://www.dropbox.com/sh/b4hjk718k19cmry/AADK067dUvQ0HprCeSscaLM1a?dl=0

You may need to unlock/soften and add hard edges to the symmetry line.

Do you bake with a cage ?
If you add an hard edge but don't use a cage, you will get a split. Mikkt or not Mikkt.
Don't forget your log file. It can be exported from the Help menu of the software.
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Fabrice Piquet aka Froyok. Product Manager, Technical Artist and Documentation at Adobe.

I do not get a split on hard edges that aren't where the mesh is mirrored without using a cage FYI. It is only when the mesh is mirrored upon itself that I notice a seam whether it's hard edge or soft along the mirror line.

I've tried a low poly with a hard edge across mirror seam including a cage when baking and it still results in a seam.

Edit: Also I did new UVs where each side of the cube was a smoothing group, and everything baked perfectly and seamless EXCEPT for the mirror line. No cage, all UV splits on the corners of the cube looked great, it was just the middle UV mirror line that was showing a seam.
Last Edit: December 04, 2015, 07:33:03 pm

I replicated your issue, unfortunately I don't have a fix. It looks like even xNormal has the issue (even in its 3D viewer) so that looks like not an easy fix. Note however that the seams only in very specific lighting conditions in my case (see my attachment).

Don't forget your log file. It can be exported from the Help menu of the software.
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Fabrice Piquet aka Froyok. Product Manager, Technical Artist and Documentation at Adobe.

Yeah it also happens in UE4, very subtle seam.

What a bizarre issue, I wonder if this is just a limitation of PBR shaders/lighting. I think adding more geometry overall helps this issue out a little bit or makes it less obvious?