FBX / glTF export - how to NOT export Armature in the hierarchy ?!

Coding Python Support
1

I used to use a trick that would prevent Blender to export Armature in the skeletal hierarchy when exporting to FBX. This trick has been lost, unfortunately.

How can I modify FBX exporter to NOT export Armature as root component? (root should be root bone, not Armature with root bone being its first child)

glTF2 exporter is even worse, because it also inserts skinned mesh into hierarchy of the skeleton. Is there a way to NOT do that and have clean skeleton hierarchy in the exported glTF2 file ?

Thanks

2

Alright, posting solution for FBX (oldie, but goodie). In \blender-3.4.0\3.4\scripts\addons\io_scene_fbx\export_fbx_bin.py comment out the following lines (starts at around line 2608):

#elif ob_obj.type == ‘EMPTY’ or ob_obj.type == ‘ARMATURE’:
#empty_key = data_empties[ob_obj]
#connections.append((b"OO", get_fbx_uuid_from_key(empty_key), ob_obj.fbx_uuid, None))

That will prevent Blender exporting Armature as root joint.

1 Like
4

Sorry for the necroposting, but unfortunately the proposed solution doesn’t work (at least with blender 3.6.3), since the “Armature” bone is still exported.

5

I just tried it with Blender 4.0.2 and it works as intended:

Blender:

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image2538×1390 332 KB

Export settings:

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image293×994 43.7 KB

UE5.3.2:

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image1163×849 114 KB

P.S. For Blender 4.0.2 it starts on the line 2983 in export_fbx_bin.py

6

Commented out those 3 lines

immagine
immagine853×335 10.6 KB

Sadly I can’t embed more than one pic in the post, however same export setting of yours.
It actually works quite good when importing in Unreal, but the Armature bone is still there when imported in Unity.
I’m truly lost

1 Like
7

Using the A-Ribeiro CustomBlenderFBXExporter is the best way I found to import / export fbx-files for Unity Animation Type “Humanoid”. Should work up to blender 3.6.4.

2 Likes
8

Also used the Ribeiro addon, but it doesn’t work anyway (still, only with Unity, Unreal got the right bone hierarchy from the export). I guess that the Unreal importer automatically gets rid of the Armature bone by itself, since the same FBX reimported in Blender still has the Armature, while the one exported from Unreal doesn’t.

9

A quick Test with blender 3.4.1 and Unity 2021.1.4f1 - no problems at all…

I’ve used a fresh dl from Mixamo - only the armature because the Unity Avatar only needs the animation.

Ribeiro
Ribeiro1902×1028 266 KB

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Try renaming “Armature” into anything else in Blender and export with modified exporter.

Also, you might have two copies of the FBX exporter (one in Blender’s folder and one in Windows users/ folder).

11

Tried to rename the armature too, to no avail. Also double checked the addons folders and I have a single copy of the FBX exporter.

12

Hello, was going mad trying to resolve this, I’ve been using Mixamo, but after editing in blender and re-exporting FBX (to hand adjust vertex bone weights for example) was always getting the extra Armature folder - I have now managed to get around this ;

  • Unpack your prefab in Unity
  • Manually modify the folder structure (i.e. move stuff up and out of the unwanted armature folder, then delete unwanted folder)
  • Re-Connect prefab

Maybe not ideal as you’ll need to do this each time you re-export your FBX, but at least it works!

13

For any poor lost souls stuck on this problem I just found the solution. Just rename the armature bone to “Armature” in blender. That way unreal will detect that this is not an additional bone when importing and your life might find hapiness again :slight_smile: You’re welcome
image

Tested in
Blender 4.1
Unreal Engine 5.4.2

2 Likes
14

This looked so promising, but didn’t work for me either, unfortunately. Still an armature node in Unity on export. Blender 4.0. My next step is to give A-Ribeiro’s 4.1 version export thingy a try.
Edit: unfortunately A-Ribeiro’s addon doesn’t seem to work past 4.0, even though it did before.
Edit: it does work in 4.1., confirmed. Very useful.

15

Tried A-Ribeiro’s addon to then upload the asset into Three.JS with no success.
Extra “Armature” Bone is still present

EDIT: Armature Bone isn’t present, but animation will contain an “Armature” keyframe