From df63bc64cebb8357d938f0f33364441d54121b73 Mon Sep 17 00:00:00 2001
From: Geoff Gerber <geoffrey-gerber@noreply.localhost>
Date: Wed, 14 Feb 2024 14:53:52 +0100
Subject: [PATCH] Fix for Blender 4 armature commands

All the armature commands are off of the `data` object in `bpy.data.armatures['Armature']` in Blender 4.0.  As a result, the original commands didn't work unless `arm` was set to `bpy.data.armatures['Armature'].data`, which is different that the behavior in earlier versions.  This change is to clarify how to access the collections.

- Add section on how to add/remove Bone Collection.
---
 .../4.0/upgrading/bone_collections.md         | 42 ++++++++++++-------
 1 file changed, 27 insertions(+), 15 deletions(-)

diff --git a/docs/release_notes/4.0/upgrading/bone_collections.md b/docs/release_notes/4.0/upgrading/bone_collections.md
index f2871c3d..bd9040cd 100644
--- a/docs/release_notes/4.0/upgrading/bone_collections.md
+++ b/docs/release_notes/4.0/upgrading/bone_collections.md
@@ -16,6 +16,18 @@ Python code that was working with armature layers and bone collections.
 - Each layer that contains one or more bones will be converted. Empty
   layers are skipped.
 
+### Creating And Deleting Bone Collections
+
+Adding:
+```
+arm.data.collections.new('IK Controls')
+```
+Removing:
+```
+ik_controls = arm.data.collections['IK Controls']
+ik_controls = arm.data.collections.remove(ik_controls)
+```
+
 ### Changing Visibility
 
 Blender 3.6 and older:
@@ -28,11 +40,11 @@ arm.layers[0] = False
 Blender 4.0:
 
 ``` Python
-for bcoll in arm.collections:
+for bcoll in arm.data.collections:
     bcoll.is_visible = True
 
-arm.collections['IK Controls'].is_visible = False
-arm.collections[0].is_visible = False
+arm.data.collections['IK Controls'].is_visible = False
+arm.data.collections[0].is_visible = False
 ```
 
 ### Assigning & Unassigning Bones
@@ -47,10 +59,10 @@ arm.bones['arm_lower_R'].layers[1] = True
 Blender 4.0:
 
 ``` Python
-arm.collections['IK Controls'].assign(arm.bones['arm_lower_R'])
-arm.collections['IK Controls'].unassign(arm.bones['arm_lower_R'])
-arm.collections[2].assign(arm.bones['arm_lower_R'])
-arm.collections[2].unassign(arm.bones['arm_lower_R'])
+arm.data.collections['IK Controls'].assign(arm.data.bones['arm_lower_R'])
+arm.data.collections['IK Controls'].unassign(arm.data.bones['arm_lower_R'])
+arm.data.collections[2].assign(arm.data.bones['arm_lower_R'])
+arm.data.collections[2].unassign(arm.data.bones['arm_lower_R'])
 ```
 
 ### Assigning bone to collections of another Bone:
@@ -65,9 +77,9 @@ Blender 4.0 (until there is a
 `bone.collections.set(other_collections)` function):
 
 ``` Python
-bone = arm.bones['arm_lower_R']
+bone = arm.data.bones['arm_lower_R']
 bone.collections.clear()
-for bcoll in arm.bones['other_bone'].collections:
+for bcoll in arm.data.bones['other_bone'].collections:
     bcoll.assign(bone)
 ```
 
@@ -84,10 +96,10 @@ Blender 4.0:
 
 ``` Python
 # Any mode but armature edit mode:
-in_collection = arm.collections['IK Controls'].bones
+in_collection = arm.data.collections['IK Controls'].bones
 
 # Armature edit mode:
-in_collection = [ebone for ebone in arm.edit_bones
+in_collection = [ebone for ebone in arm.data.edit_bones
                  if 'IK Controls' in ebone.collections]
 ```
 
@@ -105,8 +117,8 @@ arm["custom_layer_data"] = {
 Blender 4.0 has custom properties on bone collections:
 
 ``` Python
-arm.collections['IK Controls']['custom'] = 'some custom data'
-arm.collections[3]['whatever'] = 'you need'
+arm.data.collections['IK Controls']['custom'] = 'some custom data'
+arm.data.collections[3]['whatever'] = 'you need'
 ```
 
 ## Bone Groups to Bone Collections
@@ -168,7 +180,7 @@ Blender 4.0:
 
 ``` Python
 # On the armature bone:
-bone = arm.bones['arm_lower_R']
+bone = arm.data.bones['arm_lower_R']
 # Alternatively, set on the pose bone:
 bone = obj.pose.bones['arm_lower_R']
 
@@ -180,5 +192,5 @@ bone.color.palette = 'CUSTOM'
 bone.color.custom.active = (0.95, 1.0, 0.0)
 
 # Disable display of bone colors on the armature:
-arm.show_bone_colors = False
+arm.data.show_bone_colors = False
 ```
-- 
2.30.2