Is there a way to transfer a whole list (at once) of UV maps

Question

Is there a way to transfer a whole list (at once) of UV maps from one object to another identical object? By Cmd(ctrl)+L is merely possible copy one by one - super clumsy. Maybe by "bpy.ops.object.join_uvs()" but it does the same and has no more options.

Answer 1

Select the target meshes (to which you want to copy the UV map), Shift-select the source mesh (that contains the UV maps) and run the following script in the text editor.

import bpy

context = bpy.context
obj = context.active_object
uv_layer_names = [uv.name for uv in obj.data.uv_layers]

if uv_layer_names:
    for ob in context.selected_objects:
        if ob != obj and ob.type =='MESH':
            for uv_map in uv_layer_names:
                obj.data.uv_layers[uv_map].active = True
                if uv_map not in ob.data.uv_layers:
                    ob.data.uv_layers.new(name=uv_map)
                ob.data.uv_layers[uv_map].active = True
                bpy.ops.object.join_uvs()

join_uvs() source for reference: https://developer.blender.org/diffusion/B/browse/master/release/scripts/startup/bl_operators/object.py$583

Answer 2

If you have a lot of objects or data and speed is important:

import bpy
from bpy import context as C
import numpy as np

source = C.active_object
targets = (o for o in C.selected_objects if o is not source)
uvs = np.empty((2 * len(source.data.uv_layers[0].data), 1), "f")

for o in targets:
    target_layers = o.data.uv_layers
    while target_layers:
        o.data.uv_layers.remove(o.data.uv_layers[0])
    for l in source.data.uv_layers:
        l.data.foreach_get('uv', uvs)
        target_layer = target_layers.new(name=l.name, do_init=False)
        target_layer.data.foreach_set('uv', uvs)
        target_layer.active_clone = l.active_clone
        target_layer.active_render = l.active_render
        target_layer.active = l.active

As in pyCod3R's answer it copies UV_layers from active object to other selected objects.

This also makes sure the UV maps of the target objects are exactly the same:

• number of them
• names
• active
• active_render
• active_clone

The script works with an assumption the geometry is matching (the number of loops is the same).