Custom characters with non-deforming bones get deformed when imported though avatar importer

Reproduction Steps
How to reproduce:

  • Create a rig in any 3d modeling software like Blender
    • Make sure that the rig is set to not deform the mesh (bones are parented to different parts of the rig, you will not be able to reproduce this otherwise!!!)
  • Upload it to Roblox through the Avatar Importer

Beta features: All of them are enabled.

Repro files: This is the blender file for the rig:
bugMan.blend (1.3 MB)

Expected Behavior
Rig gets imported correctly as shown below:

Actual Behavior
Well… This mess:

What happened here is that the legs get tucked into the body of the rig, the left and right arms switch places but the attachments stay roughly in the same area as they were supposed to in the rig in the modeling software.

Issue Area: Studio
Issue Type: Other
Impact: High
Frequency: Constantly
Date First Experienced: 2021-12-24 11:12:00 (-05:00)

1 Like

Hello and thank you for reaching out. We are currently investigating the issue and will reach out as soon as we have more information.


Hello, I am looking into your problem right now. I am a little bit confused about your situation and afraid it might not be a bug. By looking into your blend file, it seems you did not add skin weights to your model if you want to have a skinned mesh (Please correct me if I am wrong). There are probably two ways to fix your problem depending on your needs. If you want to have a rigid mesh, then bones are not necessary in that case, and simply deleting all the rigs should solve the problem. If you want to have a skinned mesh and use bone to control your animation, you might want to skin your mesh to the bones to make it animation ready before import to studio. Currently we do not support auto-skinning in studio so you might need to finish that step in blender. Here is a tutorial showing the correct way of rigging and skinning a model in blender (Rigging a Low Poly Person | Blender 2.8 | Beginners - YouTube, see 7:30 for skinning) and hope that could be helpful. Please let me know if I missed anything.

1 Like

Also the reason why you see the weird pose in studio is probably because you parent the bone to each geometry before you move them into a T-pose? The studio importer tends to remove all the transformation after you parent your bone to your geometry. And that is why you could see the detached arms and the legs are set in the center of the body covered by the torso.

1 Like

This has happened before moving the model into a T-Pose. I haven’t checked if the issue still persists with the weights being added. I’ll update it once I get about doing it.

1 Like

One more thing: I have tried to use “with automatic weights” feature in blender to apply skin weights as shown in the link I just shared, it does not work well and it breaks the model. I would assume it is because the body part are separated and not connected together. You could try to use “with envelop weights”, it should make the importer working correctly. Another way is that you can try to build a single mesh model as most of the blender tutorial would suggest and then add rig to it.

1 Like