Make the use of bone length optional for custom shapes #46191

New Issue

Daniel Salazar · 2015-09-21T08:08:09+02:00

Daniel Salazar commented

2015-09-21 08:08:09 +02:00

Why:

The size of a controller is decided by the rigger in relation to the absolute size of the character model, not to a bone.
The length of the control bones is usually not 1.0, hence an arbitrary transformation is introduced in the custom shape which has to be counter acted by scaling the mesh by some undefined amount.
Reusing the same shape on multiple bones which have different lengths makes all shapes have different sizes. Sometimes you can not change the length of the bone because of rigging reasons.
Even if you get the scales right once, editing of edit-bones in case of changes to the rig or reusing the rig for another character will mess up the scales of the custom shapes again.
Edit bones are designed to set the default 1.0 scale of themselves. Pose bones are in charge of transforming from that default scale. It makes no sense to use a meaningless length or scale from edit mode to draw the custom shape.

Recognizing the importance of not breaking backwards compatibility, proposal is to make the scaling of custom shapes by the length of the edit bone optional. Also adding a scale factor improves re-usability.

bool=use_shape_bone_length (Default True for compat)
float=shape_bone_scale (Default 1.0)

Why: 1. The size of a controller is decided by the rigger in relation to the absolute size of the character model, not to a bone. 2. The length of the control bones is usually not 1.0, hence an arbitrary transformation is introduced in the custom shape which has to be counter acted by scaling the mesh by some undefined amount. 3. Reusing the same shape on multiple bones which have different lengths makes all shapes have different sizes. Sometimes you can not change the length of the bone because of rigging reasons. 4. Even if you get the scales right once, editing of edit-bones in case of changes to the rig or reusing the rig for another character will mess up the scales of the custom shapes again. 5. Edit bones are designed to set the default 1.0 scale of themselves. Pose bones are in charge of transforming from that default scale. It makes no sense to use a meaningless length or scale from edit mode to draw the custom shape. Recognizing the importance of not breaking backwards compatibility, proposal is to make the scaling of custom shapes by the length of the edit bone optional. Also adding a scale factor improves re-usability. bool=use_shape_bone_length (Default True for compat) float=shape_bone_scale (Default 1.0)

Daniel Salazar commented

2015-09-21 08:08:09 +02:00

Changed status to: 'Open'

Daniel Salazar commented

2015-09-21 08:08:09 +02:00

Added subscriber: @zanqdo

Sergey Sharybin commented

2015-09-21 10:52:10 +02:00

Added subscriber: @Sergey

Sergey Sharybin commented

2015-09-21 10:52:10 +02:00

Changed status from 'Open' to: 'Archived'

Sergey Sharybin closed this issue

2015-09-21 10:52:10 +02:00

Sergey Sharybin self-assigned this 2015-09-21 10:52:10 +02:00

Sergey Sharybin commented

2015-09-21 10:52:10 +02:00

Daniel, we don't accept feature requests in the bug tracker, such things are to go via mailing list (bf-funboard, bf-animsys) or via IRC.

Sergey Sharybin was unassigned by Daniel Salazar

2015-09-21 11:13:01 +02:00

Campbell Barton was assigned by Daniel Salazar

2015-09-21 11:13:01 +02:00

Daniel Salazar commented

2015-09-21 11:13:34 +02:00

I forgot to add Campbell, we discussed this on IRC

Campbell Barton commented

2015-09-21 11:59:27 +02:00

@zanqdo, set this as a design task, would be good if you could say why this is useful.

@zanqdo, set this as a design task, would be good if you could say **why** this is useful.

Joshua Leung commented

2015-09-21 14:21:23 +02:00

Added subscriber: @JoshuaLeung

Joshua Leung commented

2015-09-21 14:21:23 +02:00

It would be good to have a concrete example of a rig where this sort of functionality is necessary. I think I vaguely understand what the problem is here and why this would be useful to have.

Given the current description, I don't see any reason why we shouldn't have this. Technically, it's just a very small change in the drawing code (can be done in < 1 line)

It would be good to have a concrete example of a rig where this sort of functionality is necessary. I think I vaguely understand what the problem is here and why this would be useful to have. Given the current description, I don't see any reason why we shouldn't have this. Technically, it's just a very small change in the drawing code (can be done in < 1 line)

Campbell Barton commented

2015-09-21 14:42:03 +02:00

Was a bit reserved about adding this. but after discussion it seems reasonable.

The issue seems to be that you may want to have the reliable/matching custom object size across many bones (8+ legs for eg). and currently you need to workaround blenders use of mesh size by having many objects.

So custom scale makes sense.

The option to ignore bone length I found harder to see the need for.
As I understand it - the reasoning is that you may want to edit bone lengths, then not have to go re-adjusting all sizes.

Was a bit reserved about adding this. but after discussion it seems reasonable. The issue seems to be that you may want to have the reliable/matching custom object size across many bones (8+ legs for eg). and currently you need to workaround blenders use of mesh size by having many objects. So custom scale makes sense. The option to ignore bone length I found harder to see the need for. As I understand it - the reasoning is that you may want to edit bone lengths, then not have to go re-adjusting all sizes.

Campbell Barton commented

2015-09-21 16:05:23 +02:00

Changed status from 'Archived' to: 'Resolved'

Campbell Barton commented

2015-09-21 16:05:23 +02:00

Committed 84b074baed

Committed 84b074baed

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

Make the use of bone length optional for custom shapes #46191