I was doing some check with linked data. Mainly to see what data is linked and shared when 2 object have the mesh data.
I always thought all the data in the mesh properties or data properties on mesh data property. So you have 2 spheres and they use the same mesh data, they both would have all the same properties right?
Now i noticed that shape keys do get transferred to the other object. But vertex groups not, that seems weird. Vertex Groups are on mesh data level right? Most other items like, uv maps, vertex colors, i think all other items in that panel do show on the other object. Yet vertex groups does not. Almost feel like those are on object-level base then?!
shapekeys and vertex groups both use by.data.objects[bpy.data.mesh.name]???
I thought this was a bug and check 2.79, 2.80 and 281 they all show it?
Vertex weight is still shared between objects, it just doesn’t automatically create vgroup on instances. For me it feels like vgroup existence and naming belongs to object, while actual weight data to mesh.
Thus it makes no sense right? If it was object data, why isnt there a list dropdown like object, data, materials etc. All other options in Data panel are to that mesh, so what is vertex groups than doing there. Both show bpy.data.object[MESHNAME] so it makes no sense to me why vertex groups are not transfered
Unfortunately, vgroups are (partly) defined in objects, which means instancing a same mesh from different objects is not enough to share its groups, this is a known limitation of current code and not considered a bug.
Thanks for the link, i had also made a post for it.
I did reply just now to that link, its closed i know. Its actually quite confusing on 1 hand that its under data properties. It does make work a lot easier because its there with all the other properties. It seems more like a UI issue or papercut then.
I got a response on mine, they also showed how you actually show that vertex data. Simply add a vertexgroup and than it will show. To me this is weird, all other data properties simply do get added to linked mesh data yet VertexGroup not. But when adding a empty group it does work?!?! Makes no sense right?
just found about this, I was confused about it as well! but funnily enough in my case it is actually an adventage… because I am rigging some linked objects to a character and since these linked objects can have individual vertex groups, they can share most of the important data but each object can be assigned to a different bone.
