Add a panel to always display collision collections

Blender hides the collections settings for bodies which are a child of a
COMPOUND_PARENT; this panel makes those settings visible again. Fixes #6

README.md

@@ -73,5 +73,3 @@ Here, we can see the inital linear/angular velocities of the body (represented h
 
 Collision geometry may not have the minimal required volume for that particular shape type if vertices are offset from node; this matches Blender's behaviour.
 
-Blender's UI hides collision filtering information for children of a "Compound Parent" body - to set the collision filtering information for such an object, the child needs to be temporarily unparented from the compound.
-

addons/KHR_physics_rigid_bodies/__init__.py

@@ -7,7 +7,7 @@
 bl_info = {
     "name": "KHR_physics_rigid_bodies",
     "category": "Import-Export",
-    "version": (0, 2, 0),
+    "version": (0, 2, 1),
     "blender": (3, 6, 0),
     "location": "File > Export > glTF 2.0",
     "description": "Extension for adding rigid body information to exported glTF file",

addons/KHR_physics_rigid_bodies/blender/com/gltf2_blender_rigid_bodies_ui.py

@@ -546,6 +546,25 @@ def draw(self, context):
             row.prop(obj.khr_physics_extra_props, "cone_capsule_height")
             row.prop(obj.khr_physics_extra_props, "cone_capsule_radius_top")
 
+class KHR_PT_rigid_body_collections(KHR_PT_rigid_body_panel_base):
+    """Additional panel to display collision collections for a body, as, by default,
+    Blender will not show collections for children of a COMPOUND_PARENT"""
+    bl_label = "Collections"
+    bl_parent_id = "KHR_PT_rigid_body_panel"
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+    bl_context = "physics"
+    bl_options = {"DEFAULT_CLOSED"}
+
+    @classmethod
+    def poll(cls, context):
+        return KHR_PT_rigid_body_panel_base.rigid_body_selected(context)
+
+    def draw(self, context):
+        obj = context.object
+        layout = self.layout
+        layout.prop(obj.rigid_body, "collision_collections")
+
 
 class KHR_PT_rigid_body_constraint_panel_base(bpy.types.Panel):
     bl_label = "KHR Physics Constraint Extensions"
@@ -668,6 +687,7 @@ def draw(self, context):
     KHR_PT_rigid_body_panel,
     KHR_PT_rigid_body_motion,
     KHR_PT_rigid_body_shape,
+    KHR_PT_rigid_body_collections,
     KHR_PT_rigid_body_mass,
     KHR_PT_rigid_body_constraint_panel,
     KHR_PT_rigid_body_constraint_drives,