Baked object rotation has discontinuities #83351

New Issue

Max Konischev · 2020-12-03T08:49:59+01:00

Max Konischev commented

2020-12-03 08:49:59 +01:00

System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: GeForce GTX 970/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 452.06

Blender Version
Broken: version: 2.91.0, branch: master, commit date: 2020-11-25 08:34, hash: 0f45cab862
Worked: Never (2.80+)

Short description of error
I have a problem with animation curves after animation baking and after animation export. So you can see before/after.
It's rotation data. They're rotates on 180 degrees in X and Z-axis, and Y got to be symmetrical. It's happening after animation baking and animation export. What should i do to stay them as Before? Thank's!

Exact steps for others to reproduce the error
Note: (@iss) script in text editor is pretty much copied from bake action operator, so I assume current behavior is bug, even though I havent found exactly what causes it.

#83351.blend

Open file
Run script in text editor - Works as expected
Undo
Run Bake Action operator - Bake action operator result looks like this:

**System Information** Operating system: Windows-10-10.0.19041-SP0 64 Bits Graphics card: GeForce GTX 970/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 452.06 **Blender Version** Broken: version: 2.91.0, branch: master, commit date: 2020-11-25 08:34, hash: `0f45cab862` Worked: Never (2.80+) **Short description of error** I have a problem with animation curves after animation baking and after animation export. So you can see before/after. It's rotation data. They're rotates on 180 degrees in X and Z-axis, and Y got to be symmetrical. It's happening after animation baking and animation export. What should i do to stay them as Before? Thank's! **Exact steps for others to reproduce the error** Note: (@iss) script in text editor is pretty much copied from bake action operator, so I assume current behavior is bug, even though I havent found exactly what causes it. [#83351.blend](https://archive.blender.org/developer/F9499704/T83351.blend) - Open file - Run script in text editor - Works as expected - Undo - Run Bake Action operator - Bake action operator result looks like this: ![WQpeE.png](https://archive.blender.org/developer/F9429110/WQpeE.png)

Max Konischev commented

2020-12-03 08:49:59 +01:00

Added subscriber: @KoniFilms

Richard Antalik commented

2020-12-09 12:22:07 +01:00

Added subscriber: @iss

Richard Antalik commented

2020-12-09 12:22:07 +01:00

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

Richard Antalik commented

2020-12-09 12:22:07 +01:00

For help using Blender, please try one of the community websites: https://www.blender.org/community/

If you think this is bug, please clarify how exactly did you expor/import data.

For help using Blender, please try one of the community websites: https://www.blender.org/community/ If you think this is bug, please clarify how exactly did you expor/import data.

Max Konischev commented

2020-12-09 12:52:04 +01:00

In #83351#1071659, @iss wrote:
For help using Blender, please try one of the community websites: https://www.blender.org/community/

If you think this is bug, please clarify how exactly did you expor/import data.

I've opened the case in stackexchange, but got just one recommendation: to send it to you as the bug.
Just open my bug.blend file and do "baking animation" for the camera, you'll see changes in rotation data. If you'll do export in fbx you'll see it too.

> In #83351#1071659, @iss wrote: > For help using Blender, please try one of the community websites: https://www.blender.org/community/ > > If you think this is bug, please clarify how exactly did you expor/import data. I've opened the case in stackexchange, but got just one recommendation: to send it to you as the bug. Just open my bug.blend file and do "baking animation" for the camera, you'll see changes in rotation data. If you'll do export in fbx you'll see it too.

Richard Antalik changed title from ~~Problems with rotation animation keys baking~~ to Baked object rotation animation is offset

2020-12-10 09:52:39 +01:00

Richard Antalik commented

2020-12-10 09:52:39 +01:00

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

Sybren A. Stüvel changed title from ~~Baked object rotation animation is offset~~ to Baked object rotation has discontinuities

2020-12-18 12:18:36 +01:00

Sybren A. Stüvel commented

2020-12-18 12:34:33 +01:00

Added subscriber: @dr.sybren

Sybren A. Stüvel self-assigned this 2020-12-18 12:34:33 +01:00

Sybren A. Stüvel commented

2020-12-18 12:34:33 +01:00

The difference between your script and the Bake Action code is that your script doesn't do the conversions loc/rot/scale → matrix → loc/rot/scale. It's this conversion that causes the observed problems. The Bake Action operator is a bit limited in this sense.

You can select the rotation channels and then choose Key > Discontinuity (Euler) Filter in the graph editor menu. This will fix it right up.

Technical info: the Bake Action operator uses euler.make_compatible(euler_prev) to try and prevent discontinuities. This is not sufficient. The matrix → euler conversion has already picked one of the two possible rotations; see the mat3_normalized_to_compatible_eul() function in math_rotation.c for a proper implementation.

The difference between your script and the Bake Action code is that your script doesn't do the conversions loc/rot/scale → matrix → loc/rot/scale. It's this conversion that causes the observed problems. The Bake Action operator is a bit limited in this sense. You can select the rotation channels and then choose Key > Discontinuity (Euler) Filter in the graph editor menu. This will fix it right up. Technical info: the Bake Action operator uses `euler.make_compatible(euler_prev)` to try and prevent discontinuities. This is not sufficient. The matrix → euler conversion has already picked one of the two possible rotations; see the `mat3_normalized_to_compatible_eul()` function in `math_rotation.c` for a proper implementation.

blender-admin commented

2020-12-18 12:50:36 +01:00

This issue was referenced by e5528904f1

This issue was referenced by e5528904f12104ee31e7b67b54f2a4b3f14cec1e

Sybren A. Stüvel commented

2020-12-18 12:54:50 +01:00

Changed status from 'Confirmed' to: 'Resolved'

Sybren A. Stüvel closed this issue

2020-12-18 12:54:50 +01:00

Sybren A. Stüvel commented

2020-12-18 12:55:08 +01:00

The fix was too simple to not just immediately do :)

Max Konischev commented

2020-12-18 18:33:36 +01:00

Changed status from 'Resolved' to: 'Archived'

Max Konischev commented

2020-12-18 18:33:36 +01:00

I don't know what have you fixed. But i still have this problem with "Key > Discontinuity (Euler) Filter in the graph editor menu" before or after BakeAction. I need rotations value to be the same as before BakeAction or FBX-export. How could i fix it? What should i do?

Sybren A. Stüvel commented

2021-01-08 17:51:38 +01:00

Changed status from 'Archived' to: 'Resolved'

Sybren A. Stüvel commented

2021-01-08 17:51:38 +01:00

@KoniFilms please don't adjust the report status yourself, leave that to the developers working on it.

The image you see in the release notes is actually the file you attached here to this report. Which version of Blender are you testing with?

@KoniFilms please don't adjust the report status yourself, leave that to the developers working on it. The image you see in the [release notes](https://wiki.blender.org/wiki/Reference/Release_Notes/2.92/Animation-Rigging#Bake_Action) is actually the file you attached here to this report. Which version of Blender are you testing with?

Max Konischev commented

2021-01-12 11:22:47 +01:00

I tested 2.92 and looks like the problem is gone. Thank you so much guys! You're amazing!

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Baked object rotation has discontinuities #83351