FBX Export Operator Patch

[james-baber]

Major Changes

• Send to Unreal is no longer using the blender FBX export operator. Instead, it uses a patched version of the logic in the export_fbx_bin module from Blender's FBX addon. The reasoning for doing this was to fix the scale factor that gets baked into exported FBX files for SkeletalMesh and AnimSequence assets at the FBX level rather than fixing this issue by preforming operations to the blender scene and objects. (This logic was quite complex and still imposed some limitations. Now it can all be removed!). It should be noted that this change is substantial, and while we have done our best to test this, it could introduce some new bugs that were overlooked. If there are issues with the scale, please report any issues and roll back to version 2.2.1 of the addon in the meantime.
• Use object origin is now a core feature. This now uses the FBX export module to set the world location of StaticMesh, SkeletalMesh, and AnimSequence assets. This fixes some common problems that were introduced by moving objects in the blender scene pre-export.
• The Sync control rig tracks to source rig option has been added back to the ue2rigify extension. Since the Automatically scale bones feature has been removed, it made it easy to add this option back in as an extension.
  • #417

Minor Changes

• "Send to Unreal" button in settings dialog was renamed to "Push Assets" to be more accurate since the tool can also only export to disk if used in that mode.
• Check scene scale no longer has an option for 0.01. It now only checks for a scene scale of 1 since this is the only recommend way to work.

Deprecated

• The option Automatically scale bones has been removed. This was the default option that fixed the scale factor in SkeletalMesh and AnimSequence assets by scaling the object, scene, and fcurves. This is no longer needed since this is handled in the FBX export now.
• The Use object origin extension has been removed since it is now a core feature.

Tests Passing On

• Blender 3.3, 3.4
• Unreal 5.1

[james-baber]

• did use_object_origin ever work for combined assets?
• use_object_origin works for static meshes, not for combined static meshes

I believe it should are you noticing something different?

• weirdly, when testing with mannequins.blend, the meshes along with their armature that I move to a different location all get moved to origin when I 'push assets'. I'm probably missing something here?

Hmm yea that does seem odd. Are you talking about their animation keys are moving them back to center or did you re-key those to a new world location? If you run the test suite only on test_use_object_origin_option and If you set a break point here https://github.com/james-baber/BlenderTools/blob/f619c5940bb993f71deacf74786a93dacb5b5740/tests/utils/base_test_case.py#L819

This should offset both the mannequin and all its actions fcurve locations. to 1,1,1 in the blender world. And can you test manually from there?

[iigindesign]

• did use_object_origin ever work for combined assets?
• use_object_origin works for static meshes, not for combined static meshes

I believe it should are you noticing something different?

• weirdly, when testing with mannequins.blend, the meshes along with their armature that I move to a different location all get moved to origin when I 'push assets'. I'm probably missing something here?

Hmm yea that does seem odd. Are you talking about their animation keys are moving them back to center or did you re-key those to a new world location? If you run the test suite only on test_use_object_origin_option and If you set a break point here https://github.com/james-baber/BlenderTools/blob/f619c5940bb993f71deacf74786a93dacb5b5740/tests/utils/base_test_case.py#L819

This should offset both the mannequin and all its actions fcurve locations. to 1,1,1 in the blender world. And can you test manually from there?

Yes! Will test today

[james-baber]

Ok so I confirmed there is an issue with the combine meshes now, and it placing all objects at 0,0,0. Ill look into this and submit the fix.