Is it possible to create instance with different scale animation data but the same mesh with python?

Question

I want to duplicate objects. I want them to have the same geometry, with many polygons, so I do not want to create copies, I'd like to create instances. Then I want them to have different scale animations

but when I'm duplicating objects with command:

bpy.ops.object.duplicate(linked=True)

and then creating an animation of scale of duplicated object the source object has the same animation, how can I change that?

Answer 1

Here is a test script, select an object(s) and run. It will add the selected objects to a group, remove any animation already on those objects. Then using the group create 20 group instances with random locations.

Using code similar to here to create a simple 2 keyframe random scale action

2.8x

import bpy
from random import uniform

def random_scale_action():
    action = bpy.data.actions.new("RandomScaleAction")
    data_path = "scale"
    # (frame, value) for keyframe point
    for axis in [0, 1, 2]:
        # new fcurve
        fc = action.fcurves.new(data_path, index=axis)
        # add a new keyframe point
        fc.keyframe_points.add(count=2)
        for kfp in fc.keyframe_points:
            kfp.co = (uniform(1,100), uniform(0, 1))

    return action

context = bpy.context
scene = context.scene 

# create a group and add the selected objects to it.    
collection = bpy.data.collections.new("CubeGroup")
scene.collection.children.link(collection)

for obj in context.selected_objects:
    # remove any animation data.
    if obj.animation_data:
        obj.animation_data.clear()
    collection.objects.link(obj)

# create 20 randomly located dupli_groups.
for i in range(20):
    obj = context.active_object     
    me = obj.data
    me_copy = me.copy()
    
    ob = bpy.data.objects.new("Mesh Copy", me_copy)
    ob.location = [uniform(0,10) for i in range(3)]
    context.collection.objects.link(ob)
    
    # Add action to instanced object
    ob.animation_data_create()
    ob.animation_data.action = random_scale_action()
    
    bpy.data.collections[collection.name].objects.link(ob)
    
    context.view_layer.update()

---

2.7x

    import bpy
    from random import uniform

    def random_scale_action():
        action = bpy.data.actions.new("RandomScaleAction")
        data_path = "scale"
        # (frame, value) for keyframe point
        for axis in [0, 1, 2]:
            # new fcurve
            fc = action.fcurves.new(data_path, index=axis)
            # add a new keyframe point
            fc.keyframe_points.add(count=2)
            for kfp in fc.keyframe_points:
                kfp.co = (uniform(1,100), uniform(0, 1))
      
        return action

    context = bpy.context
    scene = context.scene 

    # create a group and add the selected objects to it.    
    group = bpy.data.groups.new("CubeGroup")
    for obj in context.selected_objects:
        # remove any animation data.
        if obj.animation_data:
            obj.animation_data.clear()
        group.objects.link(obj)
    # create 20 randomly located dupli_groups.
    for i in range(20):     
        instance = bpy.data.objects.new('dupli_group', None)
        instance.location = [uniform(0,10) for i in range(3)]
        instance.dupli_type = 'GROUP'
        instance.dupli_group = group
        scene.objects.link(instance)
        instance.animation_data_create()
        # give a random scale action
        instance.animation_data.action = random_scale_action()

Answer 2

This has been tested in 2.8:

If the original (template) object is named 'Original':

original_mesh_data = bpy.data.objects['Original'].data
# Create new object with linked mesh data
new_object = bpy.data.objects.new('CopiedMesh', original_mesh_data)

# Create animation data for new object
new_object.animation_data_create()

# Copy (do not link) original object’s action into new object’s action
new_object.animation_data.action = template_object.animation_data.action.copy()

# Renamed action if desired
new_object.animation_data.action.name = ‘NewAction’