Skinned FBX shows strange texture glitch
Using 3DS Max 2017, I have modeled, rigged, and skinned a character and have optimized it to one mesh, one texture map, and one bone structure. I have followed the export/import settings on the Lens Studio website. For the most part, it works wonderfully. My issue is this:
When I import the skinned (and/or animated) FBX to Lens Studio, the texture shows a strange flicker and dark areas. When I import the FBX without the bones or skin modifier, the texture looks fine.
I have been able to recreate this glitch using a standard cylinder. In the attached image, the skinned cylinder is on the left (you can see strange black and white areas on the surface), and the exact same cylinder with no skin modifier is on the right (texture looks fine).
I have also recreated the glitch using an Editable Mesh and an Editable Poly (same results for both). Also, I have exported the mesh with and without the uvw unwrap modifier in the stack (same results for both).
Can anyone provide insight on what is happening here? How can I fix this and make the textures smooth even with the skinned version?
I would suggest to check your normals on the rigged mesh and make sure it's facing the right direction.
If it did not work for you, can you please share your rigged model.
thanks for your reply. I have confirmed the normals are facing the correct direction, and the glitch is still happening. I tried a few different things with the mesh before exporting. I also experimented a bit with the material in Lens Studio to no avail. I have attached a screenshot of several different cylinders with different workflows. The screenshot shows what each cylinder looks like in Lens Studio, each cylinder's 3DS Max workflow, and the FBX export settings. You can see in the "Lens Studio" area of the image that the UVW Unwrap modifier seems to be what is creating the texture glitch in Lens Studio (although you can see the number 2 skinned cylinder without the unwrap also is slightly glitched). Unfortunately, the UVW Unwrap modifier is necessary to have the textures where they need to be. (I have also attached the 3DS Max 2017 working file).
3DS Max 2017 working file:
Thanks for sharing the model.
We're gonna investigate with the development team and I will keep you posted.
this type of artifacts could also have to do with wrong smoothing groups. You could try to make them all the same smoothing group, just to see if the problem persists. Or use the autosmooth modifier to try to solve it.
thank you for your reply. I experimented a bit with smoothing groups like you suggested. I tried three different smoothing group combinations on skinned cylinders:
All three of these tests showed the same results as before (like cylinder 1, 4, 5, and 6 in above screenshot).
I've put this project on a soft hold until I hear back from Amir, but thank you for your help! If anybody else has any ideas I'd love to try them out.
I wanted to follow up on this thread because I found a work-around for this issue. It is not the most optimized workflow, but it produced the results I was looking for. There may be more to it, but basically the visual glitch was being created when the skinned mesh had visible surfaces that had more than 4 edges (like the top of this cylinder).
To solve this, I created an inset with 0 value on those polygons. After this, the skin still applied to the new vertices, and even if the glitch was still there, it was in 0 space so it was not visible in the final Lens.