Maniphest T96064

can't redefine object local axis
Closed, Archived
Actions

Assigned To
None
Authored By
jl (WoL)
Feb 27 2022, 8:56 PM
Tags
  • BF Blender
Subscribers
Germano Cavalcante (mano-wii)
jl (WoL)
Pratik Borhade (PratikPB2123)

Description

System Information
Operating system: linux
Graphics card:

Blender Version
Broken: 3.0.1

Short description of error
once a 2d spline is created, there is no way to change the local projection axis, but theses axis are used by modifiers like mirror

Exact steps for others to reproduce the error

  1. open a blend file with some content
  2. move 3d cursor to some face, Z pointing at normal of face
  3. shift+a -> curves -> bezier
  4. set spline to 2d, both filled, closed loop, extrude to some value
  5. x -> vertices (remove everything)
  6. draw something that you want to mirror (so draw half part of the part) with the axis you want to use not aligned to some local axis
  7. apply a mirror modifier

optional :

  1. go out of edit mode
  2. go back to edit mode, to "refine the mirror"

what I get the spline local axis are created according to the 3d cursor axis, but if at creation time the 3d cursor axis aren´t correctly oriented there is no way to fix that
the local coordinates HAVE TO BE CORRECTLY oriented since they are used as parameter to the mirror transform

what I would like :
be able to move the origin, axis of local projection while in edition
could be an entry in object properties -> transform (like Delta transform) like " object properties -> transform -> local referential"

Event Timeline

jl (WoL) created this task.Feb 27 2022, 8:56 PM
Germano Cavalcante (mano-wii) changed the task status from Needs Triage to Needs Information from User.Feb 28 2022, 9:35 PM
Germano Cavalcante (mano-wii) added a subscriber: Germano Cavalcante (mano-wii).

I'm not sure what you mean by "local projection axis" and how the Mirror modifier relates to the problem.
Remembering that a 2D curve only has two coordinates, X and Y, and a 3D curve has the coordinates X, Y and Z. So for 2D curves the Z coordinate is always 0 (zero).
Can you provide a file showing the issue?

jl (WoL) added a comment.Mar 1 2022, 12:17 PM

according to https://zims-en.kiwix.campusafrica.gos.orange.com/wikibooks_en_all_maxi/A/Blender_3D:_Noob_to_Pro/Coordinate_Spaces_in_Blender

there is the global coordinates, which is the "world coordinates" and "local coordinates" that use as origin "object Mode -> Object -> Set Origin" but it's axis (euler rotations) are created once for all

see this screenshot : I created a 3d objects using some reference surface (I want to add details to an existing 3D object) by moving the 3D cursor (orientation to geometry) since I want the object to be symetric, I drawn only half of the detail

I displayed the "local" gizmo in "object gizmo" so that we can see local axis

now I activate the mirror modifier using "Y"axis , as you can see the mirror is performed using the local referential (and not the global that we can see on the top right corner) (which is the expected)

what is wrong is that I can set the local origin using "object Mode -> Object -> Set Origin" but I can't change the local axis, so that the mirror won´t perform correctly
so, now that I see that the Y axis isn't correctly oriented, I want to change it, but it was created "once for all" using the 3D cursor axis at time of shift+a....
I tried to set the axis correctly by changing 3d cursor's eulers angles before creation but it's too difficult to get the right angle.... and error prone (have to retry, retry, retry.....)
so I'm really puzzled why blender allow to move the orgin but not set the axis of an object... what if I want later to refine the object and notice that the local projection system isn't correct? I must detroy all and restart from scratch????

here is the blend file used for this

blender-local-axis.blend311 KBDownload

Germano Cavalcante (mano-wii) added a comment.Mar 1 2022, 3:19 PM

The explanation is still confusing.
Set Origin to 3D Cursor only changes the position of the origin, not the orientation.
The orientation remains the same, the Local.
Orientation and position are different things.

The issue reported here is a request for modified/improved behavior and not a bug in current behavior.

For user requests and feedback, other channels are indicated: https://wiki.blender.org/wiki/Communication/Contact#User_Feedback_and_Requests

jl (WoL) added a comment.EditedMar 2 2022, 11:22 AM

"Set Origin to 3D Cursor only changes the position of the origin, not the orientation."
yes, and it's where it's wrong, it should change the orientation as well, to match the one of 3D cursor, since both the origin location AND axes are used in transforms like mirror, this makes no sens to only set the position! (and for me, it's a bug of the current behavior, because the "origin" in 3D isn't only the coordinates of a point BUT the local referential AND more if the tools that you can apply don't allow to set information like mirror axis)

Pratik Borhade (PratikPB2123) added a subscriber: Pratik Borhade (PratikPB2123).Mar 2 2022, 11:23 AM
Germano Cavalcante (mano-wii) closed this task as Archived.Mar 2 2022, 4:45 PM
In T96064#1316017, @jl (WoL) wrote:

"Set Origin to 3D Cursor only changes the position of the origin, not the orientation."
yes, and it's where it's wrong, it should change the orientation as well, to match the one of 3D cursor, since both the origin location AND axes are used in transforms like mirror, this makes no sens to only set the position! (and for me, it's a bug of the current behavior, because the "origin" in 3D isn't only the coordinates of a point BUT the local referential AND more if the tools that you can apply don't allow to set information like mirror axis)

This is not something that can simply be changed.
Some users would certainly prefer the operator to continue working as it is.
We could make everyone happy by adding an option to the operator.
But in doing so, wouldn't we just be duplicating what the operator in Object → Transform → Align to Transform Orientation already does?

Anyway, this is not a bug.
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://wiki.blender.org/wiki/Communication/Contact#User_Feedback_and_Requests

Thanks for the report anyway.

For more information on why this isn't considered a bug, visit: https://wiki.blender.org/wiki/Reference/Not_a_bug