glTF export: manage collection instances / linked collection / armature proxy

13 files changed, 86 insertions, 47 deletions

diff --git a/io_scene_gltf2/__init__.py b/io_scene_gltf2/__init__.py
index 01a4402c..b52fe818 100755
--- a/io_scene_gltf2/__init__.py
+++ b/io_scene_gltf2/__init__.py
@@ -15,7 +15,7 @@
 bl_info = {
     'name': 'glTF 2.0 format',
     'author': 'Julien Duroure, Norbert Nopper, Urs Hanselmann, Moritz Becher, Benjamin Schmithüsen, Jim Eckerlein, and many external contributors',
-    "version": (1, 2, 50),
+    "version": (1, 2, 51),
     'blender': (2, 82, 7),
     'location': 'File > Import-Export',
     'description': 'Import-Export as glTF 2.0',
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_export.py b/io_scene_gltf2/blender/exp/gltf2_blender_export.py
index 6d9ab8bb..2989ec31 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_export.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_export.py
@@ -30,7 +30,8 @@ from io_scene_gltf2.io.exp.gltf2_io_user_extensions import export_user_extension
 def save(context, export_settings):
     """Start the glTF 2.0 export and saves to content either to a .gltf or .glb file."""
     if bpy.context.active_object is not None:
-        bpy.ops.object.mode_set(mode='OBJECT')
+        if bpy.context.active_object.mode != "OBJECT": # For linked object, you can't force OBJECT mode
+            bpy.ops.object.mode_set(mode='OBJECT')
 
     original_frame = bpy.context.scene.frame_current
     if not export_settings['gltf_current_frame']:
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_extract.py b/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
index bb7451ad..955c5d13 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
@@ -423,7 +423,7 @@ def extract_primitive_pack(a, indices, use_tangents):
     return result_primitive
 
 
-def extract_primitives(glTF, blender_mesh, blender_object, blender_vertex_groups, modifiers, export_settings):
+def extract_primitives(glTF, blender_mesh, library, blender_object, blender_vertex_groups, modifiers, export_settings):
     """
     Extract primitives from a mesh. Polygons are triangulated and sorted by material.
 
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather.py
index f08a379b..c6fd2c38 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather.py
@@ -51,9 +51,13 @@ def __gather_scene(blender_scene, export_settings):
         nodes=[]
     )
 
-    for blender_object in blender_scene.objects:
-        if blender_object.parent is None:
-            node = gltf2_blender_gather_nodes.gather_node(blender_object, blender_scene, export_settings)
+    for _blender_object in [obj for obj in blender_scene.objects if obj.proxy is None]:
+        if _blender_object.parent is None:
+            blender_object = _blender_object.proxy if _blender_object.proxy else _blender_object
+            node = gltf2_blender_gather_nodes.gather_node(
+                blender_object,
+                blender_object.library.name if blender_object.library else None,
+                blender_scene, None, export_settings)
             if node is not None:
                 scene.nodes.append(node)
 
@@ -66,11 +70,17 @@ def __gather_animations(blender_scene, export_settings):
     animations = []
     merged_tracks = {}
 
-    for blender_object in blender_scene.objects:
+    for _blender_object in blender_scene.objects:
+
+        blender_object = _blender_object.proxy if _blender_object.proxy else _blender_object
+
         # First check if this object is exported or not. Do not export animation of not exported object
-        obj_node = gltf2_blender_gather_nodes.gather_node(blender_object, blender_scene, export_settings)
+        obj_node = gltf2_blender_gather_nodes.gather_node(blender_object,
+            blender_object.library.name if blender_object.library else None,
+            blender_scene, None, export_settings)
         if obj_node is not None:
-            animations_, merged_tracks = gltf2_blender_gather_animations.gather_animations(blender_object, merged_tracks, len(animations), export_settings)
+            # Check was done on armature, but use here the _proxy object, because this is where the animation is
+            animations_, merged_tracks = gltf2_blender_gather_animations.gather_animations(_blender_object, merged_tracks, len(animations), export_settings)
             animations += animations_
 
     if export_settings['gltf_nla_strips'] is False:
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channel_target.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channel_target.py
index 9dfbea34..6edf52cc 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channel_target.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channel_target.py
@@ -72,7 +72,9 @@ def __gather_node(channels: typing.Tuple[bpy.types.FCurve],
                   ) -> gltf2_io.Node:
 
     if driver_obj is not None:
-        return gltf2_blender_gather_nodes.gather_node(driver_obj, None, export_settings)
+        return gltf2_blender_gather_nodes.gather_node(driver_obj,
+            driver_obj.library.name if driver_obj.library else None,
+            None, None, export_settings)
 
     if blender_object.type == "ARMATURE":
         # TODO: get joint from fcurve data_path and gather_joint
@@ -84,13 +86,17 @@ def __gather_node(channels: typing.Tuple[bpy.types.FCurve],
 
         if isinstance(blender_bone, bpy.types.PoseBone):
             if export_settings["gltf_def_bones"] is False:
-                return gltf2_blender_gather_joints.gather_joint(blender_bone, export_settings)
+                obj = blender_object.proxy if blender_object.proxy else blender_object
+                return gltf2_blender_gather_joints.gather_joint(obj, blender_bone, export_settings)
             else:
                 bones, _, _ = gltf2_blender_gather_skins.get_bone_tree(None, blender_object)
                 if blender_bone.name in [b.name for b in bones]:
-                    return gltf2_blender_gather_joints.gather_joint(blender_bone, export_settings)
+                    obj = blender_object.proxy if blender_object.proxy else blender_object
+                    return gltf2_blender_gather_joints.gather_jointb(obj, blender_bone, export_settings)
 
-    return gltf2_blender_gather_nodes.gather_node(blender_object, None, export_settings)
+    return gltf2_blender_gather_nodes.gather_node(blender_object,
+        blender_object.library.name if blender_object.library else None,
+        None, None, export_settings)
 
 
 def __gather_path(channels: typing.Tuple[bpy.types.FCurve],
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py
index 99a0ef91..6868047e 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_channels.py
@@ -97,7 +97,8 @@ def gather_animation_channels(blender_action: bpy.types.Action,
 
 
         # Retrieve channels for drivers, if needed
-        drivers_to_manage = gltf2_blender_gather_drivers.get_sk_drivers(blender_object)
+        obj_driver = blender_object.proxy if blender_object.proxy else blender_object
+        drivers_to_manage = gltf2_blender_gather_drivers.get_sk_drivers(obj_driver)
         for obj, fcurves in drivers_to_manage:
             channel = __gather_animation_channel(
                 fcurves,
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py
index 89559719..6fa5a11d 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py
@@ -168,7 +168,8 @@ def get_bone_matrix(blender_object_if_armature: typing.Optional[bpy.types.Object
 
 
         # If some drivers must be evaluated, do it here, to avoid to have to change frame by frame later
-        drivers_to_manage = get_sk_drivers(blender_object_if_armature)
+        obj_driver = blender_object_if_armature.proxy if blender_object_if_armature.proxy else blender_object_if_armature
+        drivers_to_manage = get_sk_drivers(obj_driver)
         for dr_obj, dr_fcurves in drivers_to_manage:
             vals = get_sk_driver_values(dr_obj, frame, dr_fcurves)
 
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_cache.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_cache.py
index e82d5929..7f05f751 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_cache.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_cache.py
@@ -39,7 +39,7 @@ def cached(func):
             export_settings = args[-1]
             cache_key_args = args[:-1]
 
-        __by_name = [bpy.types.Object, bpy.types.Scene, bpy.types.Material, bpy.types.Action, bpy.types.Mesh]
+        __by_name = [bpy.types.Object, bpy.types.Scene, bpy.types.Material, bpy.types.Action, bpy.types.Mesh, bpy.types.PoseBone]
 
         # we make a tuple from the function arguments so that they can be used as a key to the cache
         cache_key = ()
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_joints.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_joints.py
index 6b693575..a95efb91 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_joints.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_joints.py
@@ -24,7 +24,7 @@ from io_scene_gltf2.blender.exp import gltf2_blender_gather_skins
 
 
 @cached
-def gather_joint(blender_bone, export_settings):
+def gather_joint(blender_object, blender_bone, export_settings):
     """
     Generate a glTF2 node from a blender bone, as joints in glTF2 are simply nodes.
 
@@ -59,12 +59,12 @@ def gather_joint(blender_bone, export_settings):
 
     if export_settings["gltf_def_bones"] is False:
         for bone in blender_bone.children:
-            children.append(gather_joint(bone, export_settings))
+            children.append(gather_joint(blender_object, bone, export_settings))
     else:
         _, children_, _ = gltf2_blender_gather_skins.get_bone_tree(None, blender_bone.id_data)
         if blender_bone.name in children_.keys():
             for bone in children_[blender_bone.name]:
-                children.append(gather_joint(blender_bone.id_data.pose.bones[bone], export_settings))
+                children.append(gather_joint(blender_object, blender_bone.id_data.pose.bones[bone], export_settings))
 
     # finally add to the joints array containing all the joints in the hierarchy
     return gltf2_io.Node(
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_mesh.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_mesh.py
index 7194798f..d3f950b2 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_mesh.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_mesh.py
@@ -25,6 +25,7 @@ from io_scene_gltf2.io.exp.gltf2_io_user_extensions import export_user_extension
 
 @cached
 def gather_mesh(blender_mesh: bpy.types.Mesh,
+                library: Optional[str],
                 blender_object: Optional[bpy.types.Object],
                 vertex_groups: Optional[bpy.types.VertexGroups],
                 modifiers: Optional[bpy.types.ObjectModifiers],
@@ -32,15 +33,15 @@ def gather_mesh(blender_mesh: bpy.types.Mesh,
                 material_names: Tuple[str],
                 export_settings
                 ) -> Optional[gltf2_io.Mesh]:
-    if not skip_filter and not __filter_mesh(blender_mesh, vertex_groups, modifiers, export_settings):
+    if not skip_filter and not __filter_mesh(blender_mesh, library, vertex_groups, modifiers, export_settings):
         return None
 
     mesh = gltf2_io.Mesh(
-        extensions=__gather_extensions(blender_mesh, vertex_groups, modifiers, export_settings),
-        extras=__gather_extras(blender_mesh, vertex_groups, modifiers, export_settings),
-        name=__gather_name(blender_mesh, vertex_groups, modifiers, export_settings),
-        weights=__gather_weights(blender_mesh, vertex_groups, modifiers, export_settings),
-        primitives=__gather_primitives(blender_mesh, blender_object, vertex_groups, modifiers, material_names, export_settings),
+        extensions=__gather_extensions(blender_mesh, library, vertex_groups, modifiers, export_settings),
+        extras=__gather_extras(blender_mesh, library, vertex_groups, modifiers, export_settings),
+        name=__gather_name(blender_mesh, library, vertex_groups, modifiers, export_settings),
+        weights=__gather_weights(blender_mesh, library, vertex_groups, modifiers, export_settings),
+        primitives=__gather_primitives(blender_mesh, library, blender_object, vertex_groups, modifiers, material_names, export_settings),
     )
 
     if len(mesh.primitives) == 0:
@@ -61,6 +62,7 @@ def gather_mesh(blender_mesh: bpy.types.Mesh,
 
 
 def __filter_mesh(blender_mesh: bpy.types.Mesh,
+                  library: Optional[str],
                   vertex_groups: Optional[bpy.types.VertexGroups],
                   modifiers: Optional[bpy.types.ObjectModifiers],
                   export_settings
@@ -72,6 +74,7 @@ def __filter_mesh(blender_mesh: bpy.types.Mesh,
 
 
 def __gather_extensions(blender_mesh: bpy.types.Mesh,
+                        library: Optional[str],
                         vertex_groups: Optional[bpy.types.VertexGroups],
                         modifiers: Optional[bpy.types.ObjectModifiers],
                         export_settings
@@ -80,6 +83,7 @@ def __gather_extensions(blender_mesh: bpy.types.Mesh,
 
 
 def __gather_extras(blender_mesh: bpy.types.Mesh,
+                    library: Optional[str],
                     vertex_groups: Optional[bpy.types.VertexGroups],
                     modifiers: Optional[bpy.types.ObjectModifiers],
                     export_settings
@@ -107,6 +111,7 @@ def __gather_extras(blender_mesh: bpy.types.Mesh,
 
 
 def __gather_name(blender_mesh: bpy.types.Mesh,
+                  library: Optional[str],
                   vertex_groups: Optional[bpy.types.VertexGroups],
                   modifiers: Optional[bpy.types.ObjectModifiers],
                   export_settings
@@ -115,6 +120,7 @@ def __gather_name(blender_mesh: bpy.types.Mesh,
 
 
 def __gather_primitives(blender_mesh: bpy.types.Mesh,
+                        library: Optional[str],
                         blender_object: Optional[bpy.types.Object],
                         vertex_groups: Optional[bpy.types.VertexGroups],
                         modifiers: Optional[bpy.types.ObjectModifiers],
@@ -122,6 +128,7 @@ def __gather_primitives(blender_mesh: bpy.types.Mesh,
                         export_settings
                         ) -> List[gltf2_io.MeshPrimitive]:
     return gltf2_blender_gather_primitives.gather_primitives(blender_mesh,
+                                                             library,
                                                              blender_object,
                                                              vertex_groups,
                                                              modifiers,
@@ -130,6 +137,7 @@ def __gather_primitives(blender_mesh: bpy.types.Mesh,
 
 
 def __gather_weights(blender_mesh: bpy.types.Mesh,
+                     library: Optional[str],
                      vertex_groups: Optional[bpy.types.VertexGroups],
                      modifiers: Optional[bpy.types.ObjectModifiers],
                      export_settings
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_nodes.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_nodes.py
index 2eaf56f5..3b0fab2d 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_nodes.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_nodes.py
@@ -32,7 +32,7 @@ from io_scene_gltf2.io.exp.gltf2_io_user_extensions import export_user_extension
 from io_scene_gltf2.io.com.gltf2_io_debug import print_console
 
 
-def gather_node(blender_object, blender_scene, export_settings):
+def gather_node(blender_object, library, blender_scene, dupli_object_parent, export_settings):
     # custom cache to avoid cache miss when called from animation
     # with blender_scene=None
 
@@ -41,15 +41,15 @@ def gather_node(blender_object, blender_scene, export_settings):
         gather_node.__cache = {}
         gather_node.__export_settings = export_settings
 
-    if blender_scene is None and blender_object.name in gather_node.__cache:
-        return gather_node.__cache[blender_object.name]
+    if blender_scene is None and (blender_object.name, library) in gather_node.__cache:
+        return gather_node.__cache[(blender_object.name, library)]
 
-    node = __gather_node(blender_object, blender_scene, export_settings)
-    gather_node.__cache[blender_object.name] = node
+    node = __gather_node(blender_object, library, blender_scene, dupli_object_parent, export_settings)
+    gather_node.__cache[(blender_object.name, library)] = node
     return node
 
 @cached
-def __gather_node(blender_object, blender_scene, export_settings):
+def __gather_node(blender_object, library, blender_scene, dupli_object_parent, export_settings):
     # If blender_scene is None, we are coming from animation export
     # Check to know if object is exported is already done, so we don't check
     # again if object is instanced in scene : this check was already done when exporting object itself
@@ -62,7 +62,7 @@ def __gather_node(blender_object, blender_scene, export_settings):
         extensions=__gather_extensions(blender_object, export_settings),
         extras=__gather_extras(blender_object, export_settings),
         matrix=__gather_matrix(blender_object, export_settings),
-        mesh=__gather_mesh(blender_object, export_settings),
+        mesh=__gather_mesh(blender_object, library, export_settings),
         name=__gather_name(blender_object, export_settings),
         rotation=None,
         scale=None,
@@ -121,19 +121,30 @@ def __gather_camera(blender_object, export_settings):
 def __gather_children(blender_object, blender_scene, export_settings):
     children = []
     # standard children
-    for child_object in blender_object.children:
-        if child_object.parent_bone:
+    for _child_object in blender_object.children:
+        if _child_object.parent_bone:
             # this is handled further down,
             # as the object should be a child of the specific bone,
             # not the Armature object
             continue
-        node = gather_node(child_object, blender_scene, export_settings)
+
+        child_object = _child_object.proxy if _child_object.proxy else _child_object
+
+        node = gather_node(child_object,
+            child_object.library.name if child_object.library else None,
+            blender_scene, None, export_settings)
         if node is not None:
             children.append(node)
     # blender dupli objects
     if blender_object.instance_type == 'COLLECTION' and blender_object.instance_collection:
         for dupli_object in blender_object.instance_collection.objects:
-            node = gather_node(dupli_object, blender_scene, export_settings)
+            if dupli_object.parent is not None:
+                continue
+            if dupli_object.type == "ARMATURE":
+                continue # There is probably a proxy
+            node = gather_node(dupli_object,
+                dupli_object.library.name if dupli_object.library else None,
+                blender_scene, blender_object.name, export_settings)
             if node is not None:
                 children.append(node)
 
@@ -147,7 +158,7 @@ def __gather_children(blender_object, blender_scene, export_settings):
             bones = [blender_object.pose.bones[b.name] for b in bones]
         for blender_bone in bones:
             if not blender_bone.parent:
-                joint = gltf2_blender_gather_joints.gather_joint(blender_bone, export_settings)
+                joint = gltf2_blender_gather_joints.gather_joint(blender_object, blender_bone, export_settings)
                 children.append(joint)
                 root_joints.append(joint)
         # handle objects directly parented to bones
@@ -165,7 +176,7 @@ def __gather_children(blender_object, blender_scene, export_settings):
             parent_joint = find_parent_joint(root_joints, child.parent_bone)
             if not parent_joint:
                 continue
-            child_node = gather_node(child, None, export_settings)
+            child_node = gather_node(child, None, None, None, export_settings)
             if child_node is None:
                 continue
             blender_bone = blender_object.pose.bones[parent_joint.name]
@@ -236,7 +247,7 @@ def __gather_matrix(blender_object, export_settings):
     return []
 
 
-def __gather_mesh(blender_object, export_settings):
+def __gather_mesh(blender_object, library, export_settings):
     if blender_object.type != "MESH":
         return None
 
@@ -313,6 +324,7 @@ def __gather_mesh(blender_object, export_settings):
                 blender_object_for_skined_data = blender_object
 
     result = gltf2_blender_gather_mesh.gather_mesh(blender_mesh,
+                                                   library,
                                                    blender_object_for_skined_data,
                                                    vertex_groups,
                                                    modifiers,
@@ -327,8 +339,6 @@ def __gather_mesh(blender_object, export_settings):
 
 
 def __gather_name(blender_object, export_settings):
-    if blender_object.instance_type == 'COLLECTION' and blender_object.instance_collection:
-        return "Duplication_Offset_" + blender_object.name
     return blender_object.name
 
 
@@ -364,7 +374,7 @@ def __gather_trans_rot_scale(blender_object, export_settings):
     sca = gltf2_blender_extract.convert_swizzle_scale(sca, export_settings)
 
     if blender_object.instance_type == 'COLLECTION' and blender_object.instance_collection:
-        trans = -gltf2_blender_extract.convert_swizzle_location(
+        trans -= gltf2_blender_extract.convert_swizzle_location(
             blender_object.instance_collection.instance_offset, None, None, export_settings)
     translation, rotation, scale = (None, None, None)
     trans[0], trans[1], trans[2] = gltf2_blender_math.round_if_near(trans[0], 0.0), gltf2_blender_math.round_if_near(trans[1], 0.0), \
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_primitives.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_primitives.py
index cca86432..f841f0e2 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_primitives.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_primitives.py
@@ -33,6 +33,7 @@ from io_scene_gltf2.io.com.gltf2_io_debug import print_console
 @cached
 def gather_primitives(
         blender_mesh: bpy.types.Mesh,
+        library: Optional[str],
         blender_object: Optional[bpy.types.Object],
         vertex_groups: Optional[bpy.types.VertexGroups],
         modifiers: Optional[bpy.types.ObjectModifiers],
@@ -46,7 +47,7 @@ def gather_primitives(
     """
     primitives = []
 
-    blender_primitives = __gather_cache_primitives(blender_mesh, blender_object,
+    blender_primitives = __gather_cache_primitives(blender_mesh, library, blender_object,
         vertex_groups, modifiers, export_settings)
 
     for internal_primitive in blender_primitives:
@@ -82,6 +83,7 @@ def gather_primitives(
 @cached
 def __gather_cache_primitives(
         blender_mesh: bpy.types.Mesh,
+        library: Optional[str],
         blender_object: Optional[bpy.types.Object],
         vertex_groups: Optional[bpy.types.VertexGroups],
         modifiers: Optional[bpy.types.ObjectModifiers],
@@ -93,7 +95,7 @@ def __gather_cache_primitives(
     primitives = []
 
     blender_primitives = gltf2_blender_extract.extract_primitives(
-        None, blender_mesh, blender_object, vertex_groups, modifiers, export_settings)
+        None, blender_mesh, library, blender_object, vertex_groups, modifiers, export_settings)
 
     for internal_primitive in blender_primitives:
         primitive = {
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py
index 2513b073..fa95e543 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py
@@ -131,10 +131,10 @@ def __gather_joints(blender_object, export_settings):
         # build the hierarchy of nodes out of the bones
         for blender_bone in blender_object.pose.bones:
             if not blender_bone.parent:
-                root_joints.append(gltf2_blender_gather_joints.gather_joint(blender_bone, export_settings))
+                root_joints.append(gltf2_blender_gather_joints.gather_joint(blender_object, blender_bone, export_settings))
     else:
         _, children_, root_joints = get_bone_tree(None, blender_object)
-        root_joints = [gltf2_blender_gather_joints.gather_joint(i, export_settings) for i in root_joints]
+        root_joints = [gltf2_blender_gather_joints.gather_joint(blender_object, i, export_settings) for i in root_joints]
 
     # joints is a flat list containing all nodes belonging to the skin
     joints = []
@@ -147,7 +147,7 @@ def __gather_joints(blender_object, export_settings):
         else:
             if node.name in children_.keys():
                 for child in children_[node.name]:
-                    __collect_joints(gltf2_blender_gather_joints.gather_joint(blender_object.pose.bones[child], export_settings))
+                    __collect_joints(gltf2_blender_gather_joints.gather_joint(blender_object, blender_object.pose.bones[child], export_settings))
 
     for joint in root_joints:
         __collect_joints(joint)