Auto IK Double Generates IK constraints #80437

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Ovionis · 2020-09-03T19:09:46+02:00

Ovionis commented

2020-09-03 19:09:46 +02:00

System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: GeForce GTX 770/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 432.00

Blender Version
Broken: version: 2.91.0 Alpha, branch: master, commit date: 2020-09-01 07:02, hash: c78c425266
Worked: (newest version of Blender that worked as expected)

Short description of error
When you Grab/Move/Translate a bone in pose mode, using Targetless IK constraint, another IK constraint is created that interferes with it.

Exact steps for others to reproduce the error
Add a bone chain (maybe 7 bones)
Note: version 1 requires connected bones.

Version 1:
enable Auto IK on the rig (3D Viewport >> N Panel >> Tool >> Pose Options >> Auto IK)
select a child bone and try to move it.
If you look at the bone constraints panel when you do this, you will see two [TempConstraint] IK constraints.

Version 2
Add an IK constraint to one of the bones. (for fun, name it "TempConstraint")
Now try to move it.
A second IK constraint [TempConstraint] will be seen in the bone constraints panel
If you have Auto IK enabled (Version 1), there will now be 3 different IK constraints on the bone.

Aside from the visual glitchyness of this doubling, this "does" still work.

However in a case like Version 2 when you have an IK constraint and Auto IK enabled,
or in my particular case where I have a constraint but want to toggle its Chain Length,
when the Chain Length does not equal to the original's Chain Length, the IK does not update the bones in the chain.

2020-09-03 11-57-56.mp4

In My Usage, I'm using an addon to essentially just change the [Temp_IK_Constraint] IK constraint, with the mouse wheel (like the default Auto IK does).

Note: I say "TempConstraint" but I just realized by default, their name is actually hidden (the name is "TempConstraint", "TempConstraint.001" and etc, I just have a custom panel that doesn't hide their name)

**System Information** Operating system: Windows-10-10.0.19041-SP0 64 Bits Graphics card: GeForce GTX 770/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 432.00 **Blender Version** Broken: version: 2.91.0 Alpha, branch: master, commit date: 2020-09-01 07:02, hash: `c78c425266` Worked: (newest version of Blender that worked as expected) **Short description of error** When you Grab/Move/Translate a bone in pose mode, using Targetless IK constraint, another IK constraint is created that interferes with it. **Exact steps for others to reproduce the error** Add a bone chain (maybe 7 bones) Note: version 1 requires connected bones. **Version 1:** enable Auto IK on the rig (3D Viewport >> N Panel >> Tool >> Pose Options >> Auto IK) select a child bone and try to move it. If you look at the bone constraints panel when you do this, you will see two [TempConstraint] IK constraints. **Version 2** Add an IK constraint to one of the bones. (for fun, name it "TempConstraint") Now try to move it. A second IK constraint [TempConstraint] will be seen in the bone constraints panel If you have Auto IK enabled (Version 1), there will now be 3 different IK constraints on the bone. - - - - - - Aside from the visual glitchyness of this doubling, this "does" still work. However in a case like Version 2 when you have an IK constraint and Auto IK enabled, or in my particular case where I have a constraint but want to toggle its Chain Length, when the Chain Length does not equal to the original's Chain Length, the IK does not update the bones in the chain. [2020-09-03 11-57-56.mp4](https://archive.blender.org/developer/F8836788/2020-09-03_11-57-56.mp4) In My Usage, I'm using an addon to essentially just change the [Temp_IK_Constraint] IK constraint, with the mouse wheel (like the default Auto IK does). Note: I say "TempConstraint" but I just realized by default, their name is actually hidden (the name is "TempConstraint", "TempConstraint.001" and etc, I just have a custom panel that doesn't hide their name)

Ovionis commented

2020-09-03 19:09:46 +02:00

Added subscriber: @Phigon

Richard Antalik commented

2020-09-10 04:43:44 +02:00

Added subscribers: @dr.sybren, @iss

Richard Antalik commented

2020-09-10 04:43:44 +02:00

I am not sure if this is bug really. This option works as described in manual: https://docs.blender.org/manual/en/dev/animation/armatures/posing/tool_settings.html#bpy-types-pose-use-auto-ik

@dr.sybren what do you think?

I am not sure if this is bug really. This option works as described in manual: https://docs.blender.org/manual/en/dev/animation/armatures/posing/tool_settings.html#bpy-types-pose-use-auto-ik @dr.sybren what do you think?

blender-admin commented

2020-09-14 23:10:56 +02:00

This issue was referenced by 7a0a60dde8

This issue was referenced by 7a0a60dde8b4bf120ab7977e476bf5c82b2a63ad

Philipp Oeser commented

2020-09-14 23:32:16 +02:00

Added subscribers: @HooglyBoogly, @ZedDB, @lichtwerk

Philipp Oeser commented

2020-09-14 23:32:16 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Philipp Oeser commented

2020-09-14 23:32:16 +02:00

The fact that these temporary constraints actually show up in the constraint stack came with eaa44afe70
I guess while strictly correct, these temporary constraints should still be hidden from the UI @HooglyBoogly? see D8895: Dont show temporary IK constraints in the constraint stack

Now, why do we have two of them?
It looks like even before that commit, add_temporary_ik_constraint was called twice (actually generating two constraints).

from pose_grab_with_ik_add (Auto IK checkbox)
from add_pose_transdata

1  add_temporary_ik_constraint               transform_convert_armature.c 257  0x41fab61 
2  pose_grab_with_ik_add                     transform_convert_armature.c 362  0x41faf91 
3  pose_grab_with_ik                         transform_convert_armature.c 463  0x41fb2b9 
4  createTransPose                           transform_convert_armature.c 832  0x41fc43e 
5  createTransData                           transform_convert.c          1163 0x41f7120 
6  initTransform                             transform.c                  1759 0x41f0315

1  add_temporary_ik_constraint               transform_convert_armature.c 257  0x41fab61 
2  add_pose_transdata                        transform_convert_armature.c 707  0x41fbe1a 
3  createTransPose                           transform_convert_armature.c 842  0x41fc4b4 
4  createTransData                           transform_convert.c          1163 0x41f7120 
5  initTransform                             transform.c                  1759 0x41f0315

Why is that?
Because of 9a7f5f1bb4

I guess we should not create a temporary IK constraint on a bone that already has one @ZedDB ? see D8894: Dont add temporary IK constraints twice
(note that D8894 still does not solve the chainlength problem described in this report -- so in general I think it would be best to make sure Auto IK is always preferred if used in conjunction with targetless IK constraints)

The fact that these temporary constraints actually show up in the constraint stack came with eaa44afe70 I guess while strictly correct, these temporary constraints should still be hidden from the UI @HooglyBoogly? see [D8895: Dont show temporary IK constraints in the constraint stack](https://archive.blender.org/developer/D8895) Now, why do we have two of them? It looks like even before that commit, `add_temporary_ik_constraint` was called twice (actually generating two constraints). - from `pose_grab_with_ik_add` (`Auto IK` checkbox) - from `add_pose_transdata` ``` 1 add_temporary_ik_constraint transform_convert_armature.c 257 0x41fab61 2 pose_grab_with_ik_add transform_convert_armature.c 362 0x41faf91 3 pose_grab_with_ik transform_convert_armature.c 463 0x41fb2b9 4 createTransPose transform_convert_armature.c 832 0x41fc43e 5 createTransData transform_convert.c 1163 0x41f7120 6 initTransform transform.c 1759 0x41f0315 ``` ``` 1 add_temporary_ik_constraint transform_convert_armature.c 257 0x41fab61 2 add_pose_transdata transform_convert_armature.c 707 0x41fbe1a 3 createTransPose transform_convert_armature.c 842 0x41fc4b4 4 createTransData transform_convert.c 1163 0x41f7120 5 initTransform transform.c 1759 0x41f0315 ``` Why is that? Because of 9a7f5f1bb4 I guess we should not create a temporary IK constraint on a bone that already has one @ZedDB ? see [D8894: Dont add temporary IK constraints twice](https://archive.blender.org/developer/D8894) (note that [D8894](https://archive.blender.org/developer/D8894) still does not solve the chainlength problem described in this report -- so in general I think it would be best to make sure Auto IK is always preferred if used in conjunction with targetless IK constraints)

Philipp Oeser self-assigned this 2020-09-16 10:20:55 +02:00

blender-admin commented

2020-09-17 18:22:42 +02:00

This issue was referenced by 41e4079365

This issue was referenced by 41e40793650aa23ad525c395706eae15ec82bff9

blender-admin commented

2020-09-17 18:22:42 +02:00

This issue was referenced by a985b8bd9e

This issue was referenced by a985b8bd9efd0295be7e9d44eb17359a16bb8613

Philipp Oeser commented

2020-09-18 13:21:49 +02:00

Changed status from 'Confirmed' to: 'Resolved'

Philipp Oeser closed this issue

2020-09-18 13:21:49 +02:00

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Auto IK Double Generates IK constraints #80437