Animated object instances export frozen in place #104875

New Issue

Thomas Barlow · 2023-09-07T16:30:58+02:00

Thomas Barlow commented

2023-09-07 16:30:58 +02:00

System Information
Operating system: Windows-10-10.0.19045-SP0 64 Bits
Graphics card: NVIDIA GeForce GTX 1070 Ti/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 536.40

Blender Version
Broken: version: 4.0.0 Alpha, branch: main, commit date: 2023-09-01 21:43, hash: de09bdb510a0
Worked: (newest version of Blender that worked as expected)

Addon Information
Name: FBX format (5, 6, 0)
Author: Campbell Barton, Bastien Montagne, Jens Restemeier, @Mysteryem

Short description of error
Exporting an animated object with instancing enabled results in the instances being frozen in place in animation.

This was first identified as a bug in the code due to the use of the ob_obj variable that might by referenced before assignment 33a7345509/io_scene_fbx/export_fbx_bin.py (L2257) and this issue represents the effects of that bug.

The issue happens because the world-space matrices of the instances need to be updated each frame, but the bugged code is not doing so correctly.

.blend first frame	.blend last frame

.fbx first frame	.fbx last frame

Exact steps for others to reproduce the error

Open the attached .blend
Start an FBX export
Disable Bake Animation>NLA Strips
Disable Bake Animation>All Actions
Finish the FBX export
Import the exported .fbx and compare to the .blend

**System Information** Operating system: Windows-10-10.0.19045-SP0 64 Bits Graphics card: NVIDIA GeForce GTX 1070 Ti/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 536.40 **Blender Version** Broken: version: 4.0.0 Alpha, branch: main, commit date: 2023-09-01 21:43, hash: `de09bdb510a0` Worked: (newest version of Blender that worked as expected) **Addon Information** Name: FBX format (5, 6, 0) Author: Campbell Barton, Bastien Montagne, Jens Restemeier, @Mysteryem **Short description of error** Exporting an animated object with instancing enabled results in the instances being frozen in place in animation. This was first identified as a bug in the code due to the use of the `ob_obj` variable that might by referenced before assignment https://projects.blender.org/blender/blender-addons/src/commit/33a73455099428a93e2d4f54cc0ee5ae76db871f/io_scene_fbx/export_fbx_bin.py#L2257 and this issue represents the effects of that bug. The issue happens because the world-space matrices of the instances need to be updated each frame, but the bugged code is not doing so correctly. | .blend first frame | .blend last frame | | -- | -- | | ![image](/attachments/4fbe870f-5018-412c-b463-20a724c02def) | ![image](/attachments/09bb415e-e6ce-479c-ab46-a8a87d76eb97) | | .fbx first frame | .fbx last frame | | -- | -- | | ![image](/attachments/6c98b52b-6fe5-4832-a3ff-2326e8829dd3) | ![image](/attachments/1f92958f-44ae-4f3c-a475-04f4bef1d75e) | **Exact steps for others to reproduce the error** 1. Open the attached .blend 1. Start an FBX export 1. Disable `Bake Animation`>`NLA Strips` 1. Disable `Bake Animation`>`All Actions` 1. Finish the FBX export 1. Import the exported .fbx and compare to the .blend

image.png

125 KiB

FBXDuplicubeAnimation.blend

108 KiB

image.png

112 KiB

FBXDuplicubeAnimation4.0.0a.fbx

38 KiB

image.png

114 KiB

image.png

114 KiB

Thomas Barlow added the

labels 2023-09-07 16:30:58 +02:00

Thomas Barlow referenced a pull request that will close this issue

2023-09-08 01:33:16 +02:00

Fix #104875: Animated dupli instances export frozen in place #104876

Germano Cavalcante commented

2023-09-08 15:57:36 +02:00

Appears to be a duplicate of:
#93604: FBX Exporter: Wrong Animations in exported Collection instances

But I'm considering closing the other one instead, as there are screenshots and code mentions here.

Appears to be a duplicate of: #93604: FBX Exporter: Wrong Animations in exported Collection instances But I'm considering closing the other one instead, as there are screenshots and code mentions here.

Germano Cavalcante added

and removed

labels 2023-09-08 15:58:02 +02:00

Thomas Barlow commented

2023-09-09 12:47:51 +02:00

Yes, this should be a duplicate. I hadn't initially considered instance collections, but testing my fix showed them to also be affected.

I could copy most of the content of this report into a comment on #93604 and then close this report?

Yes, this should be a duplicate. I hadn't initially considered instance collections, but testing my fix showed them to also be affected. I could copy most of the content of this report into a comment on #93604 and then close this report?

Germano Cavalcante referenced this issue

2023-09-11 15:24:19 +02:00

FBX Exporter: Wrong Animations in exported Collection instances #93604

Germano Cavalcante commented

2023-09-11 15:27:02 +02:00

@Mysteryem, I already closed the other one, thanks for testing.

If necessary, the description here can be edited to include the file in the other report:

fbx-collection-instance-animation-bug.blend

@Mysteryem, I already closed the other one, thanks for testing. If necessary, the description here can be edited to include the file in the other report: [fbx-collection-instance-animation-bug.blend](https://archive.blender.org/developer/F12687051/fbx-collection-instance-animation-bug.blend)

Thomas Barlow closed this issue

2023-09-11 17:29:17 +02:00

Thomas Barlow referenced this issue from a commit

2023-09-11 17:29:17 +02:00

Fix #104875: Animated dupli instances export frozen in place

Blender Bot added

and removed

labels 2023-09-11 17:29:24 +02:00