No Indicator to Tell Whether the Displayed Transform Values of a Parented Object is Based on World or Parent Space #118367

New Issue

gotanidea · 2024-02-16T11:49:48+01:00

gotanidea commented

2024-02-16 11:49:48 +01:00

System Information
Operating system: Windows 11
Graphics card: Nvidia RTX 3060

Blender Version
Broken: 3.2.2, 4.0.1
Worked:

Short description of error
I have Cube A, Cone A, Cube B and Cone B that occupy the same space in 3D viewport.

However, after parenting Cube A to Cone A and Cube B to Cone B, the displayed transform values of Cube A and Cube B become different, despite still occupying the same space in 3D viewport.

Exact steps for others to reproduce the error

Open the blend file, then compare the transform values of Cube A and Cube B.
If you would like to parent them yourself, parent Cube A to Cone A with Keep Transform option and do the same to Cube B/ Cone B, but use the command from Parent Inverse add-on to make the transform values of Cube B displayed based on the parent space.

**System Information** Operating system: Windows 11 Graphics card: Nvidia RTX 3060 **Blender Version** Broken: 3.2.2, 4.0.1 Worked: **Short description of error** I have Cube A, Cone A, Cube B and Cone B that occupy the same space in 3D viewport. However, after parenting Cube A to Cone A and Cube B to Cone B, the displayed transform values of Cube A and Cube B become different, despite still occupying the same space in 3D viewport. **Exact steps for others to reproduce the error** 1. Open the blend file, then compare the transform values of Cube A and Cube B. 2. If you would like to parent them yourself, parent Cube A to Cone A with Keep Transform option and do the same to Cube B/ Cone B, but use the command from Parent Inverse add-on to make the transform values of Cube B displayed based on the parent space.

Displayed_Transform_Values_Bug.jpg

104 KiB

Displayed_Transform_Values_Bug.blend

978 KiB

gotanidea added the

labels 2024-02-16 11:49:49 +01:00

Philipp Oeser commented

2024-02-16 12:18:42 +01:00

The documentation clearly states these are all in local space:

https://docs.blender.org/manual/en/4.1/scene_layout/object/properties/transforms.html

The documentation clearly states these are all in local space: https://docs.blender.org/manual/en/4.1/scene_layout/object/properties/transforms.html

Philipp Oeser commented

2024-02-16 12:26:14 +01:00

I can imagine having something like in mesh editmode (where you can choose to have these values show for "Local" and "Global"), but this looks more like request rather than a bug.

Will have to close due to the following policy:

 Thanks for the report, but the issue reported here is a request for modified/improved behavior and not a bug in current behavior. Closing as this bug tracker is only for bugs and errors.

For user requests and feedback, please use other channels: https://developer.blender.org/docs/handbook/communication/user_feedback/

For more information on why this isn't considered a bug, visit: https://developer.blender.org/docs/handbook/bug_reports/not_a_bug/

I can imagine having something like in mesh editmode (where you can choose to have these values show for "Local" and "Global"), but this looks more like request rather than a bug. Will have to close due to the following policy: ``` Thanks for the report, but the issue reported here is a request for modified/improved behavior and not a bug in current behavior. Closing as this bug tracker is only for bugs and errors. For user requests and feedback, please use other channels: https://developer.blender.org/docs/handbook/communication/user_feedback/ For more information on why this isn't considered a bug, visit: https://developer.blender.org/docs/handbook/bug_reports/not_a_bug/ ```

Philipp Oeser closed this issue

2024-02-16 12:26:17 +01:00

Blender Bot added

and removed

labels 2024-02-16 12:26:19 +01:00

gotanidea commented

2024-02-16 13:02:42 +01:00

The documentation is incomplete. Both Cube A & Cube B occupy the same space in 3D viewport and their pivots are exactly at the same location too, yet their transform values are completely different.

Please check the transform values of Cube A and Cube B. The transform values of Cube A is clearly displayed based on world space, whereas the transform values of Cube B is displayed based on parent space.

The documentation is incomplete. Both Cube A & Cube B occupy the same space in 3D viewport and their pivots are exactly at the same location too, yet their transform values are completely different. Please check the transform values of Cube A and Cube B. The transform values of Cube A is clearly displayed based on world space, whereas the transform values of Cube B is displayed based on parent space.

Philipp Oeser commented

2024-02-16 13:23:46 +01:00

OK, I now get what you are saying.

This is because of the parent inverse matrix

For CubeA we have

C.object.matrix_parent_inverse
Matrix(((0.5, -0.0, -0.0, -3.5),
(-0.0, 0.5, 0.0, 1.5),
(-0.0, -0.0, 0.5, -0.0),
(-0.0, 0.0, -0.0, 1.0)))

For CubeB we have

C.object.matrix_parent_inverse
Matrix(((1.0, 0.0, 0.0, 0.0),
(0.0, 1.0, 0.0, 0.0),
(0.0, 0.0, 1.0, 0.0),
(0.0, 0.0, 0.0, 1.0)))

So I assume it would be good to mention (in the manual) that when displaying object transforms, this includes the parent inverse

CC @Blendify (I guess this should be moved to the https://projects.blender.org/blender/blender-manual repository -- if there only was a way to move issues across repositories...)

OK, I now get what you are saying. This is because of the [parent inverse matrix](https://docs.blender.org/manual/en/4.1/scene_layout/object/editing/parent.html#parent-inverse) For `CubeA` we have >>> C.object.matrix_parent_inverse Matrix(((0.5, -0.0, -0.0, -3.5), (-0.0, 0.5, 0.0, 1.5), (-0.0, -0.0, 0.5, -0.0), (-0.0, 0.0, -0.0, 1.0))) For `CubeB` we have >>> C.object.matrix_parent_inverse Matrix(((1.0, 0.0, 0.0, 0.0), (0.0, 1.0, 0.0, 0.0), (0.0, 0.0, 1.0, 0.0), (0.0, 0.0, 0.0, 1.0))) So I assume it would be good to mention (in the manual) that when displaying object transforms, this includes the parent inverse CC @Blendify (I guess this should be moved to the https://projects.blender.org/blender/blender-manual repository -- if there only was a way to move issues across repositories...)

Philipp Oeser reopened this issue

2024-02-16 13:23:49 +01:00

Blender Bot added

and removed

labels 2024-02-16 13:23:51 +01:00

gotanidea commented

2024-02-16 14:02:28 +01:00

OK, I now get what you are saying.

This is because of the [parent inverse matrix]

Yes, I used the command from Parent Inverse add-on to make the transform values of Cube B displayed based on the parent space.

As a comparison, I have tried the same setup in Unity 3D and Autodesk 3ds Max. Both 3D software show the transform values of Cube B based on the parent space.

> OK, I now get what you are saying. > > This is because of the [parent inverse matrix] Yes, I used the command from Parent Inverse add-on to make the transform values of Cube B displayed based on the parent space. As a comparison, I have tried the same setup in Unity 3D and Autodesk 3ds Max. Both 3D software show the transform values of Cube B based on the parent space.

gotanidea commented

2024-02-16 14:12:17 +01:00

I give you another example to show that it's a bug. Please open the attached blend file.

Cube A & Cube B occupy the exact same space in 3D viewport and both of them are parented to the same Cone, yet their Location values are different.

This inconsistency and incorrect parent-space-based transform values do not exist in Unity and 3ds Max. I have tried the same setup there.

I give you another example to show that it's a bug. Please open the attached blend file. Cube A & Cube B occupy the exact same space in 3D viewport and both of them are parented to the same Cone, yet their Location values are different. This inconsistency and incorrect parent-space-based transform values do not exist in Unity and 3ds Max. I have tried the same setup there.

Displayed_Transform_Values_Bug_1.blend

813 KiB

Richard Antalik commented

2024-02-16 19:11:46 +01:00

To me this feels very odd, that there is some internal transform matrix, and there is no way for user to tell how it is set up. Sounds like design issue though.

Germano Cavalcante commented

2024-02-16 19:48:25 +01:00

This 'Parent Inverse' issue has already been reported a few times. While it is confusing, neither the documentation nor the design is in error. It's just confusing.

Here is a report that addresses this issue:
#116689: Transforms don't show Parent Inverse information"

I think this one qualifies as a duplicate.

This 'Parent Inverse' issue has already been reported a few times. While it is confusing, neither the documentation nor the design is in error. It's just confusing. Here is a report that addresses this issue: #116689: Transforms don't show Parent Inverse information" I think this one qualifies as a duplicate.

gotanidea commented

2024-02-16 23:45:09 +01:00

This 'Parent Inverse' issue has already been reported a few times. While it is confusing, neither the documentation nor the design is in error. It's just confusing.

Here is a report that addresses this issue:
#116689: Transforms don't show Parent Inverse information"

I think this one qualifies as a duplicate.

It doesn’t make sense to have two Cubes parented to the same Cone at the exact same location in 3D viewport with different displayed transform values.

I have tried the same setup in Unity/ 3ds Max and the two Cubes have identical parent-space-based transform values there, since they are both parented to the same Cone and located at the exact same location in 3D viewport.

> This 'Parent Inverse' issue has already been reported a few times. While it is confusing, neither the documentation nor the design is in error. It's just confusing. > > Here is a report that addresses this issue: > #116689: Transforms don't show Parent Inverse information" > > I think this one qualifies as a duplicate. > It doesn’t make sense to have two Cubes parented to the same Cone at the exact same location in 3D viewport with different displayed transform values. I have tried the same setup in Unity/ 3ds Max and the two Cubes have identical parent-space-based transform values there, since they are both parented to the same Cone and located at the exact same location in 3D viewport.

thorn-neverwake commented

2024-02-17 21:00:45 +01:00

While it is confusing, neither the documentation nor the design is in error. It's just confusing.

If it's confusing enough such that the documentation appears incorrect, then the documentation needs to be improved.

>While it is confusing, neither the documentation nor the design is in error. It's just confusing. If it's confusing enough such that the documentation appears incorrect, then the documentation needs to be improved.

Pratik Borhade commented

2024-02-19 10:24:49 +01:00

Confirming till manual is updated

Pratik Borhade added

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No Indicator to Tell Whether the Displayed Transform Values of a Parented Object is Based on World or Parent Space #118367