migrating mesh level animation_data to object level and updating corresponding data_path fails to apply separately to linked duplicates #23546

New Issue

Josh Wedlake · 2010-08-27T18:11:25+02:00

Josh Wedlake commented

2010-08-27 18:11:25 +02:00

%%%The attached file contains two linked duplicate mushroom objects which share the same mesh data. The object datablocks have unique (not shared) animation_data which has been converted to nla strips (for ease of demonstration of the bug) attached to them which refers to the data_path 'data.shape_keys.keys["s1"].value'.

As I understand from Aligorith this should allow the shape key values (which are stored inside the mesh datablock rather than the object datablock) to be animated separately on a per object basis without the need to duplicate the mesh.

It seems what is actually happening is that blender is evaluating each object in turn, evaluating the animation_data but applying its effect to the mesh datablock so the two mushrooms in the file both show the same state (ie the last evaluated) rather than different states.

To see the bug in action:

scrub the timeline in the attached blend and note that the two mushrooms animate in the same way.
delete the larger of the two NLA strips and scrub the timeline - note that both mushrooms still animate identically but no with a different action (that of the remaining NLA strip)
%%%

%%%The attached file contains two linked duplicate mushroom objects which share the same mesh data. The object datablocks have unique (not shared) animation_data which has been converted to nla strips (for ease of demonstration of the bug) attached to them which refers to the data_path 'data.shape_keys.keys["s1"].value'. As I understand from Aligorith this should allow the shape key values (which are stored inside the mesh datablock rather than the object datablock) to be animated separately on a per object basis without the need to duplicate the mesh. It seems what is actually happening is that blender is evaluating each object in turn, evaluating the animation_data but applying its effect to the mesh datablock so the two mushrooms in the file both show the same state (ie the last evaluated) rather than different states. To see the bug in action: 1. scrub the timeline in the attached blend and note that the two mushrooms animate in the same way. 2. delete the larger of the two NLA strips and scrub the timeline - note that both mushrooms still animate identically but no with a different action (that of the remaining NLA strip) %%%

Josh Wedlake commented

2010-08-27 18:11:25 +02:00

Changed status to: 'Open'

Josh Wedlake commented

2010-08-27 18:23:21 +02:00

%%%sorry try this attachment...

in my attempt to make the bug easier to understand I managed to break the setup in the file, ironically because of another bug which I've just reported!%%%

%%%sorry try this attachment... in my attempt to make the bug easier to understand I managed to break the setup in the file, ironically because of another bug which I've just reported!%%%

Brecht Van Lommel commented

2010-09-15 21:27:42 +02:00

%%%This is not going to work, if the data paths refer to the same mesh, only the last evaluated animation will be applied. This can't be expected to work at the moment.%%%

Brecht Van Lommel commented

2010-09-15 21:27:42 +02:00

Changed status from 'Open' to: 'Archived'

Brecht Van Lommel closed this issue

2010-09-15 21:27:42 +02:00

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

migrating mesh level animation_data to object level and updating corresponding data_path fails to apply separately to linked duplicates #23546