Bone roll messed up after import as FBX #88272

New Issue

Tom Weber · 2021-05-13T22:24:37+02:00

Tom Weber commented

2021-05-13 22:24:37 +02:00

System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: GeForce GTX 1660 SUPER/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 461.09

Blender Version
Broken: version: 3.0.0 Alpha, branch: master, commit date: 2021-05-12 23:52, hash: blender/blender@06e62adfb8
Worked: Never

I import an FBX in Blender. The bone roll of the fingers is broken. It is not aligned with the bone axis.
I import the same FBX in DAZ3D, and the bone roll is fine. So it must be a problem with the way that Blender handles the FBX import file.
[Please fill out a short description of the error here]

Download and import this FBX file in Blender.
Pick import settings. I have used the following:

Observe, how the bone rotation is different in comparison to the bone rotation in DAZ3D:

This is the blend file: bones1.blend

Please watch the animated gif to see how to reproduce the problem:

The difference between the FBX imported in DAZ3D can clearly be seen in top view:

DAZ3D:

Blender. As one can see, the rotation tool is not aligned with the bone as is in DAZ3D, so the rotation outcome in Blender is different than in DAZ3D:

I have tried the same in Unity, and in Unity is STILL looks different, so we have 3 versions of how fbx is being imported:

And so far, only the DAZ3D fbx importing works correctly.

**System Information** Operating system: Windows-10-10.0.19041-SP0 64 Bits Graphics card: GeForce GTX 1660 SUPER/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 461.09 **Blender Version** Broken: version: 3.0.0 Alpha, branch: master, commit date: 2021-05-12 23:52, hash: `blender/blender@06e62adfb8` Worked: Never I import an FBX in Blender. The bone roll of the fingers is broken. It is not aligned with the bone axis. I import the same FBX in DAZ3D, and the bone roll is fine. So it must be a problem with the way that Blender handles the FBX import file. [Please fill out a short description of the error here] Download and import [this FBX file ](https://drive.google.com/file/d/12e2DtFcy8fqVmhOsq4DSuth7U4wmbbkH/view?usp=sharing) in Blender. Pick import settings. I have used the following: ![blender bone orientation.png](https://archive.blender.org/developer/F10096384/blender_bone_orientation.png) Observe, how the bone rotation is different in comparison to the bone rotation in DAZ3D: ![LUSij.gif](https://archive.blender.org/developer/F10096394/LUSij.gif) This is the blend file: [bones1.blend](https://archive.blender.org/developer/F10096407/bones1.blend) Please watch the animated gif to see how to reproduce the problem: ![bones5.gif](https://archive.blender.org/developer/F10096605/bones5.gif) The difference between the FBX imported in DAZ3D can clearly be seen in top view: DAZ3D: ![1daz.png](https://archive.blender.org/developer/F10097907/1daz.png) Blender. As one can see, the rotation tool is not aligned with the bone as is in DAZ3D, so the rotation outcome in Blender is different than in DAZ3D: ![2blender.png](https://archive.blender.org/developer/F10097909/2blender.png) I have tried the same in Unity, and in Unity is STILL looks different, so we have 3 versions of how fbx is being imported: ![unity1.png](https://archive.blender.org/developer/F10098096/unity1.png) And so far, only the DAZ3D fbx importing works correctly.

Tom Weber commented

2021-05-13 22:24:37 +02:00

Added subscriber: @tw2020

Ankit Meel commented

2021-06-02 20:12:38 +02:00

Added subscriber: @ankitm

Ankit Meel commented

2021-06-02 20:12:38 +02:00

#76800 (FBX "Automatic bone rotation" during animation import does not work as promised)
#87181 (Invalid armature (bone roll flipped?) when importing FBX 7.5 from mixamo.com)
#83531 (FBX Export Breaks Bone Roll Values - Simple Example)

#76800 (FBX "Automatic bone rotation" during animation import does not work as promised) #87181 (Invalid armature (bone roll flipped?) when importing FBX 7.5 from mixamo.com) #83531 (FBX Export Breaks Bone Roll Values - Simple Example)

Tom Weber commented

2021-06-02 20:16:40 +02:00

Unity has exactely the same bug.
MoBu did, too.
In Mobu 2020, the problem is fixed.
Unity has also acknowledged the bug and has it in its bug tracker .

Unity has exactely the same bug. MoBu did, too. In Mobu 2020, the problem is fixed. Unity has also acknowledged the bug and has it in its [bug tracker ](https://issuetracker.unity3d.com/issues/fbx-models-gameobjects-are-not-aligned-along-coordinate-axes-when-model-is-imported-from-daz3d).

Ankit Meel commented

2021-06-06 21:16:05 +02:00

Adding the two as subtasks so that their files can also be checked while a fix is being worked on. Since they have different steps to redo, merging into one would be confusing.