Merge branch 'master' into xr-controller-support

25 files changed, 203 insertions, 86 deletions

diff --git a/blenderkit/ui_panels.py b/blenderkit/ui_panels.py
index e2b8d700..25fa5927 100644
--- a/blenderkit/ui_panels.py
+++ b/blenderkit/ui_panels.py
@@ -1836,8 +1836,8 @@ class AssetPopupCard(bpy.types.Operator, ratings_utils.RatingsProperties):
 
             row.emboss = 'NONE'
             op = row.operator('wm.blenderkit_tooltip', text=str(s), icon_value=pcoll['trophy'].icon_id)
-            op.tooltip = 'Asset score calculated from averaged user ratings. \n\n' \
-                         'Score = quality × complexity × 10*\n\n *Happiness multiplier'
+            op.tooltip = 'Asset score calculated from user ratings. \n\n' \
+                         'Score = average quality × median complexity × 10*\n\n *Happiness multiplier'
             row.label(text='   ')
 
             tooltip_extension = f'.\n\nRatings results are shown for assets with more than {show_rating_threshold} ratings'
@@ -1847,7 +1847,7 @@ class AssetPopupCard(bpy.types.Operator, ratings_utils.RatingsProperties):
             row.label(text='   ')
 
             op = row.operator('wm.blenderkit_tooltip', text=str(c), icon_value=pcoll['dumbbell'].icon_id)
-            op.tooltip = f"Complexity, average from {rc['workingHours']} ratings" \
+            op.tooltip = f"Complexity, median from {rc['workingHours']} ratings" \
                          f"{tooltip_extension if rcount <= show_rating_threshold else ''}"
 
             if rcount <= show_rating_prompt_threshold:
@@ -2029,9 +2029,9 @@ class SetCategoryOperator(bpy.types.Operator):
 
 
 class ClosePopupButton(bpy.types.Operator):
-    """Visit subcategory"""
+    """Close popup window"""
     bl_idname = "view3d.close_popup_button"
-    bl_label = "BlenderKit close popup"
+    bl_label = "Close popup"
     bl_options = {'REGISTER', 'INTERNAL'}
 
     @classmethod
diff --git a/blenderkit/utils.py b/blenderkit/utils.py
index 096688be..42e3d331 100644
--- a/blenderkit/utils.py
+++ b/blenderkit/utils.py
@@ -692,7 +692,12 @@ def automap(target_object=None, target_slot=None, tex_size=1, bg_exception=False
                 bpy.ops.object.material_slot_select()
 
             scale = (scale.x + scale.y + scale.z) / 3.0
+
+            if tex_size == 0:# prevent division by zero, it's possible to have 0 in tex size by unskilled uploaders
+                tex_size = 1
+
             if not just_scale:
+
                 bpy.ops.uv.cube_project(
                     cube_size=scale * 2.0 / (tex_size),
                     correct_aspect=False)  # it's * 2.0 because blender can't tell size of a unit cube :)
diff --git a/io_scene_fbx/__init__.py b/io_scene_fbx/__init__.py
index 01bc5421..495e62d2 100644
--- a/io_scene_fbx/__init__.py
+++ b/io_scene_fbx/__init__.py
@@ -21,7 +21,7 @@
 bl_info = {
     "name": "FBX format",
     "author": "Campbell Barton, Bastien Montagne, Jens Restemeier",
-    "version": (4, 23, 0),
+    "version": (4, 24, 0),
     "blender": (2, 90, 0),
     "location": "File > Import-Export",
     "description": "FBX IO meshes, UV's, vertex colors, materials, textures, cameras, lamps and actions",
diff --git a/io_scene_fbx/fbx_utils.py b/io_scene_fbx/fbx_utils.py
index c35399b2..3a421423 100644
--- a/io_scene_fbx/fbx_utils.py
+++ b/io_scene_fbx/fbx_utils.py
@@ -150,7 +150,8 @@ FBX_FRAMERATES = (
 
 # ##### Misc utilities #####
 
-DO_PERFMON = True
+# Enable performance reports (measuring time used to perform various steps of importing or exporting).
+DO_PERFMON = False
 
 if DO_PERFMON:
     class PerfMon():
diff --git a/io_scene_gltf2/__init__.py b/io_scene_gltf2/__init__.py
index 08f5cbd1..9a89cfbe 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, Scurest, Norbert Nopper, Urs Hanselmann, Moritz Becher, Benjamin Schmithüsen, Jim Eckerlein, and many external contributors',
-    "version": (1, 7, 23),
+    "version": (1, 7, 28),
     'blender': (2, 91, 0),
     'location': 'File > Import-Export',
     'description': 'Import-Export as glTF 2.0',
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_extract.py b/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
index dc508d18..f7318c2b 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_extract.py
@@ -387,7 +387,7 @@ def __get_positions(blender_mesh, key_blocks, armature, blender_object, export_s
 
     # Transform for skinning
     if armature and blender_object:
-        apply_matrix = armature.matrix_world.inverted() @ blender_object.matrix_world
+        apply_matrix = armature.matrix_world.inverted_safe() @ blender_object.matrix_world
         loc_transform = armature.matrix_world @ apply_matrix
 
         loc_transform = blender_object.matrix_world
@@ -427,8 +427,8 @@ def __get_normals(blender_mesh, key_blocks, armature, blender_object, export_set
 
     # Transform for skinning
     if armature and blender_object:
-        apply_matrix = (armature.matrix_world.inverted() @ blender_object.matrix_world)
-        apply_matrix = apply_matrix.to_3x3().inverted().transposed()
+        apply_matrix = (armature.matrix_world.inverted_safe() @ blender_object.matrix_world)
+        apply_matrix = apply_matrix.to_3x3().inverted_safe().transposed()
         normal_transform = armature.matrix_world.to_3x3() @ apply_matrix
 
         normals[:] = __apply_mat_to_all(normal_transform, normals)
@@ -463,7 +463,7 @@ def __get_tangents(blender_mesh, armature, blender_object, export_settings):
 
     # Transform for skinning
     if armature and blender_object:
-        apply_matrix = armature.matrix_world.inverted() @ blender_object.matrix_world
+        apply_matrix = armature.matrix_world.inverted_safe() @ blender_object.matrix_world
         tangent_transform = apply_matrix.to_quaternion().to_matrix()
         tangents = __apply_mat_to_all(tangent_transform, tangents)
         __normalize_vecs(tangents)
@@ -482,7 +482,7 @@ def __get_bitangent_signs(blender_mesh, armature, blender_object, export_setting
     if armature and blender_object:
         # Bitangent signs should flip when handedness changes
         # TODO: confirm
-        apply_matrix = armature.matrix_world.inverted() @ blender_object.matrix_world
+        apply_matrix = armature.matrix_world.inverted_safe() @ blender_object.matrix_world
         tangent_transform = apply_matrix.to_quaternion().to_matrix()
         flipped = tangent_transform.determinant() < 0
         if flipped:
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 932ea25e..df069f79 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
@@ -317,14 +317,14 @@ def gather_keyframes(blender_object_if_armature: typing.Optional[bpy.types.Objec
     # We can ignore this keyframes
     # if there are some fcurve, we can keep only 2 keyframes, first and last
     if blender_object_if_armature is not None:
-        std = np.ptp(np.ptp([[k.value[i] for i in range(len(keyframes[0].value))] for k in keyframes], axis=0))
+        cst = all([j < 0.0001 for j in np.ptp([[k.value[i] for i in range(len(keyframes[0].value))] for k in keyframes], axis=0)])
 
         if node_channel_is_animated is True: # fcurve on this bone for this property
              # Keep animation, but keep only 2 keyframes if data are not changing
-             return [keyframes[0], keyframes[-1]] if std < 0.0001 and len(keyframes) >= 2 else keyframes
+             return [keyframes[0], keyframes[-1]] if cst is True and len(keyframes) >= 2 else keyframes
         else: # bone is not animated (no fcurve)
             # Not keeping if not changing property
-            return None if std < 0.0001 else keyframes
+            return None if cst is True else keyframes
 
     return keyframes
 
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_samplers.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_samplers.py
index d3b9e022..aca85e07 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_samplers.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_samplers.py
@@ -370,7 +370,7 @@ def __gather_output(channels: typing.Tuple[bpy.types.FCurve],
                 correction_matrix_local = axis_basis_change @ bone.bone.matrix_local
             else:
                 correction_matrix_local = (
-                    bone.parent.bone.matrix_local.inverted() @
+                    bone.parent.bone.matrix_local.inverted_safe() @
                     bone.bone.matrix_local
                 )
 
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 2acf56dd..1abe9ec1 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_joints.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_joints.py
@@ -40,7 +40,7 @@ def gather_joint(blender_object, blender_bone, export_settings):
         correction_matrix_local = axis_basis_change @ blender_bone.bone.matrix_local
     else:
         correction_matrix_local = (
-            blender_bone.parent.bone.matrix_local.inverted() @
+            blender_bone.parent.bone.matrix_local.inverted_safe() @
             blender_bone.bone.matrix_local
         )
 
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 a2fc57be..28a19c9e 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_nodes.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_nodes.py
@@ -49,7 +49,7 @@ def gather_node(blender_object, library, blender_scene, dupli_object_parent, exp
 
 @cached
 def __gather_node(blender_object, library, blender_scene, dupli_object_parent, export_settings):
-    children = __gather_children(blender_object, blender_scene, export_settings)
+    children, only_bone_children = __gather_children(blender_object, blender_scene, export_settings)
 
     camera = None
     mesh = None
@@ -64,6 +64,12 @@ def __gather_node(blender_object, library, blender_scene, dupli_object_parent, e
             # This node should be filtered out, but has un-filtered children present.
             # So, export this node, excluding its camera, mesh, skin, and weights.
             # The transformations and animations on this node will have visible effects on children.
+
+            # Armature always have children node(s) (that are bone(s))
+            # We have to check if children are only bones or not for armatures
+            if blender_object.type == "ARMATURE" and only_bone_children is True:
+                return None
+
             pass
         else:
             # This node is filtered out, and has no un-filtered children or descendants.
@@ -158,6 +164,7 @@ def __gather_camera(blender_object, export_settings):
 
 def __gather_children(blender_object, blender_scene, export_settings):
     children = []
+    only_bone_children = True # True by default, will be set to False if needed
     # standard children
     for _child_object in blender_object.children:
         if _child_object.parent_bone:
@@ -173,6 +180,7 @@ def __gather_children(blender_object, blender_scene, export_settings):
             blender_scene, None, export_settings)
         if node is not None:
             children.append(node)
+            only_bone_children = False
     # blender dupli objects
     if blender_object.instance_type == 'COLLECTION' and blender_object.instance_collection:
         for dupli_object in blender_object.instance_collection.objects:
@@ -185,6 +193,7 @@ def __gather_children(blender_object, blender_scene, export_settings):
                 blender_scene, blender_object.name, export_settings)
             if node is not None:
                 children.append(node)
+                only_bone_children = False
 
     # blender bones
     if blender_object.type == "ARMATURE":
@@ -201,6 +210,8 @@ def __gather_children(blender_object, blender_scene, export_settings):
                 root_joints.append(joint)
         # handle objects directly parented to bones
         direct_bone_children = [child for child in blender_object.children if child.parent_bone]
+        if len(direct_bone_children) != 0:
+            only_bone_children = False
         def find_parent_joint(joints, name):
             for joint in joints:
                 if joint.name == name:
@@ -246,7 +257,7 @@ def __gather_children(blender_object, blender_scene, export_settings):
 
             parent_joint.children.append(child_node)
 
-    return children
+    return children, only_bone_children
 
 
 def __gather_extensions(blender_object, export_settings):
@@ -292,6 +303,9 @@ def __gather_mesh(blender_object, library, export_settings):
     if blender_object.type != "MESH":
         return None
 
+    # Be sure that object is valid (no NaN for example)
+    blender_object.data.validate()
+
     # If not using vertex group, they are irrelevant for caching --> ensure that they do not trigger a cache miss
     vertex_groups = blender_object.vertex_groups
     modifiers = blender_object.modifiers
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 003a4d6f..5d9e31ed 100755
--- a/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py
@@ -90,7 +90,7 @@ def __gather_inverse_bind_matrices(blender_object, export_settings):
                 blender_object.matrix_world @
                 bone.bone.matrix_local
             )
-        ).inverted()
+        ).inverted_safe()
         matrices.append(inverse_bind_matrix)
 
         if export_settings['gltf_def_bones'] is False:
diff --git a/io_scene_gltf2/blender/imp/gltf2_blender_node.py b/io_scene_gltf2/blender/imp/gltf2_blender_node.py
index 041bf1eb..8e0d7cbb 100755
--- a/io_scene_gltf2/blender/imp/gltf2_blender_node.py
+++ b/io_scene_gltf2/blender/imp/gltf2_blender_node.py
@@ -184,6 +184,10 @@ class BlenderNode():
     @staticmethod
     def create_mesh_object(gltf, vnode):
         pynode = gltf.data.nodes[vnode.mesh_node_idx]
+        if not (0 <= pynode.mesh < len(gltf.data.meshes)):
+            # Avoid traceback for invalid gltf file: invalid reference to meshes array
+            # So return an empty blender object)
+            return bpy.data.objects.new(vnode.name or mesh.name, None)
         pymesh = gltf.data.meshes[pynode.mesh]
 
         # Key to cache the Blender mesh by.
diff --git a/presets/interface_theme/Deep_Grey.xml b/presets/interface_theme/Deep_Grey.xml
index 4d0c2df1..15d87f4f 100644
--- a/presets/interface_theme/Deep_Grey.xml
+++ b/presets/interface_theme/Deep_Grey.xml
@@ -1533,7 +1533,6 @@
     <panel_title>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1545,7 +1544,6 @@
     <widget_label>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1557,7 +1555,6 @@
     <widget>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="0"
diff --git a/presets/interface_theme/Maya.xml b/presets/interface_theme/Maya.xml
index 844605b6..35470fa1 100644
--- a/presets/interface_theme/Maya.xml
+++ b/presets/interface_theme/Maya.xml
@@ -1454,7 +1454,6 @@
     <panel_title>
       <ThemeFontStyle
         points="12"
-        font_kerning_style="FITTED"
         shadow="1"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1466,7 +1465,6 @@
     <widget_label>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="3"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1478,7 +1476,6 @@
     <widget>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="0"
diff --git a/presets/interface_theme/Minimal_Dark.xml b/presets/interface_theme/Minimal_Dark.xml
index c83b7742..9f3fe83c 100644
--- a/presets/interface_theme/Minimal_Dark.xml
+++ b/presets/interface_theme/Minimal_Dark.xml
@@ -1533,7 +1533,6 @@
     <panel_title>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="1"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1545,7 +1544,6 @@
     <widget_label>
       <ThemeFontStyle
         points="10"
-        font_kerning_style="FITTED"
         shadow="3"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1557,7 +1555,6 @@
     <widget>
       <ThemeFontStyle
         points="10"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="-1"
diff --git a/presets/interface_theme/Modo.xml b/presets/interface_theme/Modo.xml
index 8e7b1f47..c762e49f 100644
--- a/presets/interface_theme/Modo.xml
+++ b/presets/interface_theme/Modo.xml
@@ -1454,7 +1454,6 @@
     <panel_title>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="1"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1466,7 +1465,6 @@
     <widget_label>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="3"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1478,7 +1476,6 @@
     <widget>
       <ThemeFontStyle
         points="10"
-        font_kerning_style="FITTED"
         shadow="1"
         shadow_offset_x="0"
         shadow_offset_y="-1"
diff --git a/presets/interface_theme/Print_Friendly.xml b/presets/interface_theme/Print_Friendly.xml
index 752c2ef4..9e6d8593 100644
--- a/presets/interface_theme/Print_Friendly.xml
+++ b/presets/interface_theme/Print_Friendly.xml
@@ -1533,7 +1533,6 @@
     <panel_title>
       <ThemeFontStyle
         points="12"
-        font_kerning_style="FITTED"
         shadow="3"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1545,7 +1544,6 @@
     <widget_label>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="3"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1557,7 +1555,6 @@
     <widget>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="1"
         shadow_offset_x="0"
         shadow_offset_y="-1"
diff --git a/presets/interface_theme/White.xml b/presets/interface_theme/White.xml
index ad33a755..dcbf545d 100644
--- a/presets/interface_theme/White.xml
+++ b/presets/interface_theme/White.xml
@@ -1454,7 +1454,6 @@
     <panel_title>
       <ThemeFontStyle
         points="12"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1466,7 +1465,6 @@
     <widget_label>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1478,7 +1476,6 @@
     <widget>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="FITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="-1"
diff --git a/presets/interface_theme/XSI.xml b/presets/interface_theme/XSI.xml
index ab901413..79bba314 100644
--- a/presets/interface_theme/XSI.xml
+++ b/presets/interface_theme/XSI.xml
@@ -1454,7 +1454,6 @@
     <panel_title>
       <ThemeFontStyle
         points="12"
-        font_kerning_style="FITTED"
         shadow="2"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1466,7 +1465,6 @@
     <widget_label>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="UNFITTED"
         shadow="3"
         shadow_offset_x="0"
         shadow_offset_y="-1"
@@ -1478,7 +1476,6 @@
     <widget>
       <ThemeFontStyle
         points="11"
-        font_kerning_style="UNFITTED"
         shadow="0"
         shadow_offset_x="0"
         shadow_offset_y="0"
diff --git a/rigify/__init__.py b/rigify/__init__.py
index 1bb633f6..4b926c48 100644
--- a/rigify/__init__.py
+++ b/rigify/__init__.py
@@ -140,6 +140,11 @@ from bpy.props import (
 )
 
 
+def get_generator():
+    """Returns the currently active generator instance."""
+    return base_generate.BaseGenerator.instance
+
+
 class RigifyFeatureSets(bpy.types.PropertyGroup):
     name: bpy.props.StringProperty()
     module_name: bpy.props.StringProperty()
@@ -525,6 +530,10 @@ def register():
         description="Forces Rigify to delete and rebuild all the rig widgets. if unset, only missing widgets will be created",
         default=False)
 
+    bpy.types.Armature.rigify_mirror_widgets = BoolProperty(name="Mirror Widgets",
+        description="Make widgets for left and right side bones linked duplicates with negative X scale for the right side, based on bone name symmetry",
+        default=True)
+
     bpy.types.Armature.rigify_target_rig = PointerProperty(type=bpy.types.Object,
         name="Rigify Target Rig",
         description="Defines which rig to overwrite. If unset, a new one called 'rig' will be created",
@@ -534,6 +543,10 @@ def register():
         name="Rigify Target Rig UI",
         description="Defines the UI to overwrite. If unset, 'rig_ui.py' will be used")
 
+    bpy.types.Armature.rigify_finalize_script = PointerProperty(type=bpy.types.Text,
+        name="Finalize Script",
+        description="Run this script after generation to apply user-specific changes")
+
     bpy.types.Armature.rigify_rig_basename = StringProperty(name="Rigify Rig Name",
         description="Defines the name of the Rig. If unset, in 'new' mode 'rig' will be used, in 'overwrite' mode the target rig name will be used",
         default="")
diff --git a/rigify/base_generate.py b/rigify/base_generate.py
index 16242262..7bdb8b0e 100644
--- a/rigify/base_generate.py
+++ b/rigify/base_generate.py
@@ -189,6 +189,8 @@ class LegacyRig(base_rig.BaseRig):
 class BaseGenerator:
     """Base class for the main generator object. Contains rig and plugin management code."""
 
+    instance = None
+
     def __init__(self, context, metarig):
         self.context = context
         self.scene = context.scene
diff --git a/rigify/generate.py b/rigify/generate.py
index 5e95bd99..a2d9a5d1 100644
--- a/rigify/generate.py
+++ b/rigify/generate.py
@@ -25,7 +25,7 @@ import time
 from .utils.errors import MetarigError
 from .utils.bones import new_bone
 from .utils.layers import ORG_LAYER, MCH_LAYER, DEF_LAYER, ROOT_LAYER
-from .utils.naming import ORG_PREFIX, MCH_PREFIX, DEF_PREFIX, ROOT_NAME, make_original_name
+from .utils.naming import ORG_PREFIX, MCH_PREFIX, DEF_PREFIX, ROOT_NAME, make_original_name, change_name_side, get_name_side, Side
 from .utils.widgets import WGT_PREFIX
 from .utils.widgets_special import create_root_widget
 from .utils.mechanism import refresh_all_drivers
@@ -165,27 +165,44 @@ class Generator(base_generate.BaseGenerator):
                 for obj in list(old_collection.objects):
                     bpy.data.objects.remove(obj)
 
-            # Rename widgets and collection if renaming
-            if self.rig_old_name:
-                old_prefix = WGT_PREFIX + self.rig_old_name + "_"
-                new_prefix = WGT_PREFIX + self.obj.name + "_"
+            # Rename the collection
+            old_collection.name = new_group_name
 
-                for obj in list(old_collection.objects):
-                    if obj.name.startswith(old_prefix):
-                        new_name = new_prefix + obj.name[len(old_prefix):]
-                    elif obj.name == wgts_group_name:
-                        new_name = new_group_name
-                    else:
-                        continue
+        # Create/find widget collection
+        self.widget_collection = ensure_widget_collection(self.context, new_group_name)
+        self.use_mirror_widgets = self.metarig.data.rigify_mirror_widgets
 
-                    obj.data.name = new_name
-                    obj.name = new_name
+        # Build tables for existing widgets
+        self.old_widget_table = {}
+        self.new_widget_table = {}
+        self.widget_mirror_mesh = {}
 
-                old_collection.name = new_group_name
+        if not self.metarig.data.rigify_force_widget_update and self.obj.pose:
+            # Find all widgets from the collection referenced by the old rig
+            known_widgets = set(obj.name for obj in self.widget_collection.objects)
 
-        # Create/find widget collection
-        self.widget_collection = ensure_widget_collection(self.context, new_group_name)
-        self.wgts_group_name = new_group_name
+            for bone in self.obj.pose.bones:
+                if bone.custom_shape and bone.custom_shape.name in known_widgets:
+                    self.old_widget_table[bone.name] = bone.custom_shape
+
+            # Rename widgets in case the rig was renamed
+            name_prefix = WGT_PREFIX + self.obj.name + "_"
+
+            for bone_name, widget in self.old_widget_table.items():
+                old_data_name = change_name_side(widget.name, get_name_side(widget.data.name))
+
+                widget.name = name_prefix + bone_name
+
+                # If the mesh name is the same as the object, rename it too
+                if widget.data.name == old_data_name:
+                    widget.data.name = change_name_side(widget.name, get_name_side(widget.data.name))
+
+            # Find meshes for mirroring
+            if self.use_mirror_widgets:
+                for bone_name, widget in self.old_widget_table.items():
+                    mid_name = change_name_side(bone_name, Side.MIDDLE)
+                    if bone_name != mid_name:
+                        self.widget_mirror_mesh[mid_name] = widget.data
 
 
     def __duplicate_rig(self):
@@ -373,6 +390,11 @@ class Generator(base_generate.BaseGenerator):
         # Assign shapes to bones
         # Object's with name WGT-<bone_name> get used as that bone's shape.
         for bone in self.obj.pose.bones:
+            # First check the table built by create_widget
+            if bone.name in self.new_widget_table:
+                bone.custom_shape = self.new_widget_table[bone.name]
+                continue
+
             # Object names are limited to 63 characters... arg
             wgt_name = (WGT_PREFIX + self.obj.name + '_' + bone.name)[:63]
 
@@ -574,6 +596,14 @@ class Generator(base_generate.BaseGenerator):
         refresh_all_drivers()
 
         #----------------------------------
+        # Execute the finalize script
+
+        if metarig.data.rigify_finalize_script:
+            bpy.ops.object.mode_set(mode='OBJECT')
+            exec(metarig.data.rigify_finalize_script.as_string(), {})
+            bpy.ops.object.mode_set(mode='OBJECT')
+
+        #----------------------------------
         # Restore active collection
         view_layer.active_layer_collection = self.layer_collection
 
@@ -587,7 +617,11 @@ def generate_rig(context, metarig):
     metarig.data.pose_position = 'REST'
 
     try:
-        Generator(context, metarig).generate()
+        generator = Generator(context, metarig)
+
+        base_generate.BaseGenerator.instance = generator
+
+        generator.generate()
 
         metarig.data.pose_position = rest_backup
 
@@ -601,6 +635,9 @@ def generate_rig(context, metarig):
         # Continue the exception
         raise e
 
+    finally:
+        base_generate.BaseGenerator.instance = None
+
 
 def create_selection_set_for_rig_layer(
         rig: bpy.types.Object,
diff --git a/rigify/rigs/widgets.py b/rigify/rigs/widgets.py
index ef0bb544..0c434593 100644
--- a/rigify/rigs/widgets.py
+++ b/rigify/rigs/widgets.py
@@ -97,7 +97,7 @@ def create_ikarrow_widget(rig, bone_name, size=1.0, bone_transform_name=None, ro
 
 def create_hand_widget(rig, bone_name, size=1.0, bone_transform_name=None):
     # Create hand widget
-    obj = create_widget(rig, bone_name, bone_transform_name)
+    obj = create_widget(rig, bone_name, bone_transform_name, subsurf=2)
     if obj is not None:
         verts = [(0.0*size, 1.5*size, -0.7000000476837158*size), (1.1920928955078125e-07*size, -0.25*size, -0.6999999284744263*size), (0.0*size, -0.25*size, 0.7000000476837158*size), (-1.1920928955078125e-07*size, 1.5*size, 0.6999999284744263*size), (5.960464477539063e-08*size, 0.7229999899864197*size, -0.699999988079071*size), (-5.960464477539063e-08*size, 0.7229999899864197*size, 0.699999988079071*size), (1.1920928955078125e-07*size, -2.9802322387695312e-08*size, -0.699999988079071*size), (0.0*size, 2.9802322387695312e-08*size, 0.699999988079071*size), ]
         edges = [(1, 2), (0, 3), (0, 4), (3, 5), (4, 6), (1, 6), (5, 7), (2, 7)]
@@ -107,8 +107,6 @@ def create_hand_widget(rig, bone_name, size=1.0, bone_transform_name=None):
         mesh.from_pydata(verts, edges, faces)
         mesh.update()
 
-        mod = obj.modifiers.new("subsurf", 'SUBSURF')
-        mod.levels = 2
         return obj
     else:
         return None
@@ -116,7 +114,7 @@ def create_hand_widget(rig, bone_name, size=1.0, bone_transform_name=None):
 
 def create_foot_widget(rig, bone_name, size=1.0, bone_transform_name=None):
     # Create hand widget
-    obj = create_widget(rig, bone_name, bone_transform_name)
+    obj = create_widget(rig, bone_name, bone_transform_name, subsurf=2)
     if obj is not None:
         verts = [(-0.6999998688697815*size, -0.5242648720741272*size, 0.0*size), (-0.7000001072883606*size, 1.2257349491119385*size, 0.0*size), (0.6999998688697815*size, 1.2257351875305176*size, 0.0*size), (0.7000001072883606*size, -0.5242648720741272*size, 0.0*size), (-0.6999998688697815*size, 0.2527350187301636*size, 0.0*size), (0.7000001072883606*size, 0.2527352571487427*size, 0.0*size), (-0.7000001072883606*size, 0.975735068321228*size, 0.0*size), (0.6999998688697815*size, 0.9757352471351624*size, 0.0*size), ]
         edges = [(1, 2), (0, 3), (0, 4), (3, 5), (4, 6), (1, 6), (5, 7), (2, 7), ]
@@ -126,8 +124,6 @@ def create_foot_widget(rig, bone_name, size=1.0, bone_transform_name=None):
         mesh.from_pydata(verts, edges, faces)
         mesh.update()
 
-        mod = obj.modifiers.new("subsurf", 'SUBSURF')
-        mod.levels = 2
         return obj
     else:
         return None
diff --git a/rigify/ui.py b/rigify/ui.py
index 6ba455da..c801ac25 100644
--- a/rigify/ui.py
+++ b/rigify/ui.py
@@ -177,6 +177,9 @@ class DATA_PT_rigify_buttons(bpy.types.Panel):
                 if armature_id_store.rigify_generate_mode == 'new':
                     row.enabled = False
 
+                col.prop(armature_id_store, "rigify_mirror_widgets")
+                col.prop(armature_id_store, "rigify_finalize_script", text="Run Script")
+
         elif obj.mode == 'EDIT':
             # Build types list
             build_type_list(context, id_store.rigify_types)
diff --git a/rigify/utils/widgets.py b/rigify/utils/widgets.py
index a8691349..3f0bf252 100644
--- a/rigify/utils/widgets.py
+++ b/rigify/utils/widgets.py
@@ -28,6 +28,7 @@ from itertools import count
 
 from .errors import MetarigError
 from .collections import ensure_widget_collection
+from .naming import change_name_side, get_name_side, Side
 
 WGT_PREFIX = "WGT-"  # Prefix for widget objects
 
@@ -56,47 +57,113 @@ def obj_to_bone(obj, rig, bone_name, bone_transform_name=None):
     elif bone.custom_shape_transform:
         bone = bone.custom_shape_transform
 
-    shape_mat = Matrix.Translation(loc) @ (Euler(rot).to_matrix() @ Matrix.Diagonal(scale)).to_4x4()
+    shape_mat = Matrix.LocRotScale(loc, Euler(rot), scale)
 
     obj.rotation_mode = 'XYZ'
     obj.matrix_basis = rig.matrix_world @ bone.bone.matrix_local @ shape_mat
 
 
-def create_widget(rig, bone_name, bone_transform_name=None, *, widget_name=None, widget_force_new=False):
+def create_widget(rig, bone_name, bone_transform_name=None, *, widget_name=None, widget_force_new=False, subsurf=0):
     """ Creates an empty widget object for a bone, and returns the object.
     """
     assert rig.mode != 'EDIT'
 
-    obj_name = widget_name or WGT_PREFIX + rig.name + '_' + bone_name
+    from ..base_generate import BaseGenerator
+
     scene = bpy.context.scene
-    collection = ensure_widget_collection(bpy.context, 'WGTS_' + rig.name)
+    bone = rig.pose.bones[bone_name]
+
+    # Access the current generator instance when generating (ugh, globals)
+    generator = BaseGenerator.instance
+
+    if generator:
+        collection = generator.widget_collection
+    else:
+        collection = ensure_widget_collection(bpy.context, 'WGTS_' + rig.name)
+
+    use_mirror = generator and generator.use_mirror_widgets
+
+    if use_mirror:
+        bone_mid_name = change_name_side(bone_name, Side.MIDDLE)
+
+    obj_name = widget_name or WGT_PREFIX + rig.name + '_' + bone_name
     reuse_mesh = None
 
     # Check if it already exists in the scene
     if not widget_force_new:
-        if obj_name in scene.objects:
+        obj = None
+
+        if generator:
+            # Check if the widget was already generated
+            if bone_name in generator.new_widget_table:
+                return None
+
+            # If re-generating, check widgets used by the previous rig
+            obj = generator.old_widget_table.get(bone_name)
+
+        if not obj:
+            # Search the scene by name
+            obj = scene.objects.get(obj_name)
+
+        if obj:
+            # Record the generated widget
+            if generator:
+                generator.new_widget_table[bone_name] = obj
+
+            # Re-add to the collection if not there for some reason
+            if obj.name not in collection.objects:
+                collection.objects.link(obj)
+
+            # Flip scale for originally mirrored widgets
+            if obj.scale.x < 0 and bone.custom_shape_scale_xyz.x > 0:
+                bone.custom_shape_scale_xyz.x *= -1
+
             # Move object to bone position, in case it changed
-            obj = scene.objects[obj_name]
             obj_to_bone(obj, rig, bone_name, bone_transform_name)
 
             return None
 
-        # Delete object if it exists in blend data but not scene data.
-        # This is necessary so we can then create the object without
-        # name conflicts.
-        if obj_name in bpy.data.objects:
-            bpy.data.objects.remove(bpy.data.objects[obj_name])
-
         # Create a linked duplicate of the widget assigned in the metarig
         reuse_widget = rig.pose.bones[bone_name].custom_shape
         if reuse_widget:
+            subsurf = 0
             reuse_mesh = reuse_widget.data
 
-    # Create mesh object
-    mesh = reuse_mesh or bpy.data.meshes.new(obj_name)
+        # Create a linked duplicate with the mirror widget
+        if not reuse_mesh and use_mirror and bone_mid_name != bone_name:
+            reuse_mesh = generator.widget_mirror_mesh.get(bone_mid_name)
+
+    # Create an empty mesh datablock if not linking
+    if reuse_mesh:
+        mesh = reuse_mesh
+
+    elif use_mirror and bone_mid_name != bone_name:
+        # When mirroring, untag side from mesh name, and remember it
+        mesh = bpy.data.meshes.new(change_name_side(obj_name, Side.MIDDLE))
+
+        generator.widget_mirror_mesh[bone_mid_name] = mesh
+
+    else:
+        mesh = bpy.data.meshes.new(obj_name)
+
+    # Create the object
     obj = bpy.data.objects.new(obj_name, mesh)
     collection.objects.link(obj)
 
+    # Add the subdivision surface modifier
+    if subsurf > 0:
+        mod = obj.modifiers.new("subsurf", 'SUBSURF')
+        mod.levels = subsurf
+
+    # Record the generated widget
+    if generator:
+        generator.new_widget_table[bone_name] = obj
+
+    # Flip scale for right side if mirroring widgets
+    if use_mirror and get_name_side(bone_name) == Side.RIGHT:
+        if bone.custom_shape_scale_xyz.x > 0:
+            bone.custom_shape_scale_xyz.x *= -1
+
     # Move object to bone position and set layers
     obj_to_bone(obj, rig, bone_name, bone_transform_name)
 
@@ -187,7 +254,7 @@ def widget_generator(generate_func=None, *, register=None, subsurf=0):
     """
     @functools.wraps(generate_func)
     def wrapper(rig, bone_name, bone_transform_name=None, widget_name=None, widget_force_new=False, **kwargs):
-        obj = create_widget(rig, bone_name, bone_transform_name, widget_name=widget_name, widget_force_new=widget_force_new)
+        obj = create_widget(rig, bone_name, bone_transform_name, widget_name=widget_name, widget_force_new=widget_force_new, subsurf=subsurf)
         if obj is not None:
             geom = GeometryData()
 
@@ -197,10 +264,6 @@ def widget_generator(generate_func=None, *, register=None, subsurf=0):
             mesh.from_pydata(geom.verts, geom.edges, geom.faces)
             mesh.update()
 
-            if subsurf:
-                mod = obj.modifiers.new("subsurf", 'SUBSURF')
-                mod.levels = subsurf
-
             return obj
         else:
             return None