FBX export bug (restpose missing, wrong rotations) #85496

New Issue

Aleksei · 2021-02-09T11:21:16+01:00

Aleksei commented

2021-02-09 11:21:16 +01:00

System Information
Operating system: Windows-10-10.0.17134-SP0 64 Bits
Graphics card: Intel(R) HD Graphics 530 Intel 4.5.0 - Build 25.20.100.6326

Blender Version
Broken: version: 2.91.2, branch: master, commit date: 2021-01-19 16:15, hash: blender/blender@5be9ef4177
Worked: (newest version of Blender that worked as expected)

Short description of error
When exporting only animation to .fbx, the rest position is not exported.

Exact steps for others to reproduce the error

Check armature with animation.
Export only animation to fbx.
Import animation from fbx.
Rest pose of imported armature not available.
If choose action with animation to same armature without animation, animation incorrect.

**System Information** Operating system: Windows-10-10.0.17134-SP0 64 Bits Graphics card: Intel(R) HD Graphics 530 Intel 4.5.0 - Build 25.20.100.6326 **Blender Version** Broken: version: 2.91.2, branch: master, commit date: 2021-01-19 16:15, hash: `blender/blender@5be9ef4177` Worked: (newest version of Blender that worked as expected) **Short description of error** When exporting only animation to .fbx, the rest position is not exported. **Exact steps for others to reproduce the error** 1. Check armature with animation. 2. Export only animation to fbx. 3. Import animation from fbx. 4. Rest pose of imported armature not available. 5. If choose action with animation to same armature without animation, animation incorrect.

Aleksei commented

2021-02-09 11:21:16 +01:00

Added subscriber: @AlloteSoftware

blender-admin commented

2021-02-09 11:21:16 +01:00

#72140 was marked as duplicate of this issue

Philipp Oeser commented

2021-02-10 11:35:26 +01:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2021-02-10 11:35:26 +01:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Philipp Oeser commented

2021-02-10 11:35:26 +01:00

Could you share the .blend file from which you export?

Aleksei commented

2021-02-25 13:36:52 +01:00

test.blend
- export settings.

[test.blend](https://archive.blender.org/developer/F9838426/test.blend) ![expsettings.jpg](https://archive.blender.org/developer/F9838442/expsettings.jpg) - export settings.

Philipp Oeser commented

2021-02-25 14:17:12 +01:00

Changed status from 'Needs User Info' to: 'Confirmed'

Philipp Oeser commented

2021-02-25 14:17:12 +01:00

Can confirm there is something wrong.

(havent figured out what exactly tbh, but FBX can be incredibly complex to debug, this needs another look with more time)

Can confirm there is something wrong. (havent figured out what exactly tbh, but FBX can be incredibly complex to debug, this needs another look with more time)

Philipp Oeser changed title from ~~Animation export bug~~ to FBX export bug (restpose missing, wrong rotations)

2021-02-25 14:17:32 +01:00

Omar Emara commented

2022-03-09 08:17:01 +01:00

Added subscriber: @mulkyz

Jer Bot referenced this issue from blender/blender

2023-10-04 01:44:51 +02:00

FBX export of armature changes rest pose if without weighted mesh #113073

Germano Cavalcante referenced this issue

2023-10-24 14:45:07 +02:00

Rest Position silently prevents exporting .fbx and .glb animations #104974

Thomas Barlow commented

2023-10-24 18:54:13 +02:00

I think this may be an FBX format limitation with the features that the FBX IO addon currently supports.

FBX IO imports armature rest poses from FBX Bind Poses. FBX IO also exports FBX Bind Poses, but Bind Poses include the mesh(es) and the bones that deform the mesh(es) (and their parent bones). No meshes exported means no Bind Poses are exported. The FBX files I have that were produced by external software and have no meshes also have no Bind Poses, so I think this is expected behaviour.

The FBX SDK documentation does mention that Rest Poses are a thing too, and it sounds like they would resolve this issue, but I'm yet to see one in an actual file, so I don't know if the FBX IO addon's importer will do anything with them, nor what sort of support other software has for them.

Until we have examples of FBX files using Rest Poses or examples of FBX files using Bind Poses without meshes (I'm not sure this is possible), I don't think there's anything we can do to fix this, aside from creating a custom solution that isn't part of the FBX standard, e.g. writing rest pose transformation to a Custom Property (FBX User Property) on each bone.

I think this may be an FBX format limitation with the features that the FBX IO addon currently supports. FBX IO imports armature rest poses from FBX Bind Poses. FBX IO also exports FBX Bind Poses, but Bind Poses include the mesh(es) and the bones that deform the mesh(es) (and their parent bones). No meshes exported means no Bind Poses are exported. The FBX files I have that were produced by external software and have no meshes also have no Bind Poses, so I think this is expected behaviour. The FBX SDK documentation does mention that Rest Poses are a thing too, and it sounds like they would resolve this issue, but I'm yet to see one in an actual file, so I don't know if the FBX IO addon's importer will do anything with them, nor what sort of support other software has for them. Until we have examples of FBX files using Rest Poses or examples of FBX files using Bind Poses without meshes (I'm not sure this is possible), I don't think there's anything we can do to fix this, aside from creating a custom solution that isn't part of the FBX standard, e.g. writing rest pose transformation to a Custom Property (FBX User Property) on each bone.

Thomas Barlow referenced this issue

2023-10-24 19:15:56 +02:00

FBX export of armature changes rest pose if without weighted mesh #104937

Jer Bot commented

2023-11-17 19:11:05 +01:00

@Mysteryem , did some testing in both Maya and Blender.... and yeah, seems that Blender is doing all is can, under the circumstances. Maya is no better (needs a mesh). Also asked around a bit and received confirmation that things are working as expected. As much as I was hoping for a built-in solution, it doesn't seem like there's a way to store a "rest" (aka "bind") pose in FBX without a mesh.

So I'd say you can close this ticket.

Thanks for digging in!

@Mysteryem , did some testing in both Maya and Blender.... and yeah, seems that Blender is doing all is can, under the circumstances. Maya is no better (needs a mesh). Also asked around a bit and received confirmation that things are working as expected. As much as I was hoping for a built-in solution, it doesn't seem like there's a way to store a "rest" (aka "bind") pose in FBX without a mesh. So I'd say you can close this ticket. Thanks for digging in!

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