Author Topic: FBX imports sometimes has all edges softened--disregards normals  (Read 3402 times)

I am occasionally importing a FBX file and find that all the edges have all been softened (or averaged). This is contrary to what I am exporting out of Maya 2015. On one occasion, I did some further checking and realized that the model had some faces that were duplicated. When I deleted them, suddenly the fbx came in as expected.

That may be a red herring.

However, I have imported a giant mix of meshes for reference and am seeing the same problem. I'm not going to hunt down the problem this time. But I am seeing this problem occuring more and more. There is little option to resolve mesh errors in Substance Painter. So  I am curious if there has been any others experiencing this problem and what they might have done to fix it?

As a Maya user myself, I never had issues of this kind when importing in Substance Painter. I would suggest looking into the way to you are modeling your meshes. Duplicate faces are usually an user error.

You can also try older FBX version when exporting, like FBX 2014 or 2013, maybe that will help.
Don't forget your log file. It can be exported from the Help menu of the software.
Fabrice Piquet aka Froyok. Product Manager, Technical Artist and Documentation at Adobe.

I had this problem once with my mesh. Indeed it turned out to be bad geometry (non-manifold) that caused this. The only solution that I found was to clean the mesh.

I've been modeling for 20 years--so I'm not a novice modeler. So I found Froyak's remarks a little dismissive of the problem. I make hundreds of models monthly. Its very easy in all that modeling to make mistakes.

So here I am again, I ran into another problem with a mesh. Sometimes minor errors are like finding a needle in a haystack. Substance Painter requires that I fix these errors before I can even start--which is fine. But It would be helpful if Substance painter could give some sort of clue where its having issues (how about paint the problem poly's red on import). Other programs issue warnings or are resilient enough to not misbehave.

It's an odd manifestation. Everything comes in smoothed. Its like the importer hit a snag and just decided to go into full smooth mode.

In every case thus far, it is the result of a collapsed polygon. These sometimes are easy to filter out in Maya. Sometimes they aren't. In the case I fixed, it was a 5 vertice square polygon where the 5th vertice was a collapsed face that looked like a edge. Maya's zero-area filter didn't pick it up because it was part of legitimate polygon.

This seems to be a FBX issue. I exported the same model out as a OBJ and it came up fine in Substance Painter.

I also have this issue rather frequently. Been working in Maya for 10 + years and I know how to harden an edge. All other render software sees a hard edge, Unity, Unreal, hell, even Photoshop. Remodeling the object and making sure that the geometry is clean does not solve the issue. Perhaps it has to do with a position of polygons that Painter doesn't like?

There are multiple versions of fbx formats out there, differentiated by year.  Zbrush for example, for its fbx plug-in you can choose export versions between years 2011-2016.

Double check your app's fbx import/export preference settings if available.  Blender, another example, fbx export options for smoothing includes edge, face or normals only for fbx version "fbx 7.4 binary".

I found that converting the object to vertices and welding them all, then running it through mesh clean up fixed the issue,.