[solved] 3D Viewport mesh display issue (Designer 5.3)

AdvisableRobin

Hey PC,

So I'm having this small issue with one of my models in the viewport in SD 5.3. The issue seems to stem from the mesh itself since any custom mesh I use to display in the viewport is borked, on top of that normal maps display really strangely which makes me think it might have something to do with the mesh normals. Otherwise I'm pretty stumped by this.

Mesh itself


Mesh with normals

AdvisableRobin

Upon further investigation, OBJ format works perfectly fine it seems that FBX is causing the problem. My FBX settings are smoothing groups and tangents & binormals. It doesn't seem to matter what year version except that 2016 doesn't work at all.

As an aside as well it seems that custom 3D meshes in obj format prevents the viewport light from being moved around for some reason.

NicolasW

Make sure you make a "reset xform" on the mesh before exporting (we are working on a bug fix to avoid that).

oblomov

Also, I don't think we support FBX 2016 yet. Can you try exporting to FBX 2015 instead ?

AdvisableRobin

I went back and double checked the export. Reset xform, cleared history and made sure the fbx version was set to 2015, still getting issues. I'm going to try clearing all edge hardness data and redo it and hope that maybe Maya is just having issues with the normals. Will post if it works at all.

NicolasW

Can you send me the mesh ?

AdvisableRobin

All you should need to do is make sure you have something in the normal output slot of the substance, even if it is just the solid normal color, if you wish to repro it.
Dropbox

NicolasW

Hum.. It looks good on my side.



What are your settings here



And here ?

AdvisableRobin

Alright so that fixed everything, in the Tangent Space Plugin section, I had compute binormals in fragment shader checked. Thanks many!

I'm curious what exactly does that mean? Is it just discarding imported binormals and recomputing them?

NicolasW

"Compute binormals in fragment shader" means
- if the fbx has NOT been exported with tangent/binormals, or
- if the "Always recompute tangent frames" option is enabled

then the tangent and binormal will be computed per pixel (compared to per vertex).

If you plan to use/view the mesh and normal map in Unreal Engine 4 (and one of the two aforementioned conditions are valid) then you should enable it.

Also if you do that, you'll have to rebake the normal so that the normal map takes this into account to keep the normal synced.

Another workflow would be to
- export the fbx from max/maya with the tangent/binormals
- in SD, do not recompute them
- bake in SD
- in Unreal, upon import: do not recompute tangents
-> this way the tangent/binormals are always the ones from the mesh

AdvisableRobin

Alright, I think I understand that. Thanks a ton for helping me through the issue!