Disabling root motion now correctly exports the root bone in the bind pose in animations

The description for Root Motion has also been updated to better explain how the setting works.

io_scene_psk_psa/psa/builder.py

@@ -23,12 +23,12 @@ class PsaBuildOptions:
     def __init__(self):
         self.animation_data: Optional[AnimData] = None
         self.sequences: List[PsaExportSequence] = []
-        self.bone_filter_mode = 'ALL'
+        self.bone_filter_mode: str = 'ALL'
         self.bone_group_indices: List[int] = []
-        self.should_ignore_bone_name_restrictions = False
+        self.should_ignore_bone_name_restrictions: bool = False
-        self.sequence_name_prefix = ''
+        self.sequence_name_prefix: str = ''
-        self.sequence_name_suffix = ''
+        self.sequence_name_suffix: str = ''
-        self.root_motion = False
+        self.root_motion: bool = False
 
 
 def build_psa(context: bpy.types.Context, options: PsaBuildOptions) -> Psa:
@@ -145,10 +145,11 @@ def build_psa(context: bpy.types.Context, options: PsaBuildOptions) -> Psa:
                     pose_bone_matrix = pose_bone_parent_matrix.inverted() @ pose_bone_matrix
                 else:
                     if options.root_motion:
-                        # Export root motion
+                        # Get the bone's pose matrix, taking the armature object's world matrix into account.
                         pose_bone_matrix = armature_object.matrix_world @ pose_bone.matrix
                     else:
-                        pose_bone_matrix = pose_bone.matrix
+                        # Use the bind pose matrix for the root bone.
+                        pose_bone_matrix = armature_data.bones[pose_bone.name].matrix_local
 
                 location = pose_bone_matrix.to_translation()
                 rotation = pose_bone_matrix.to_quaternion().normalized()

io_scene_psk_psa/psa/exporter.py

@@ -63,7 +63,9 @@ class PsaExportPropertyGroup(PropertyGroup):
         name='Root Motion',
         options=empty_set,
         default=False,
-        description='The root bone will be transformed as it appears in the scene',
+        description='When enabled, the root bone will be transformed as it appears in the scene.\n\n'
+                    'You might want to disable this if you are exporting an animation for an armature that is '
+                    'attached to another object, such as a weapon or a shield',
     )
     should_override_animation_data: BoolProperty(
         name='Override Animation Data',