added mixamo.py

Author: Roberto De Ioris

tutorials/FixingMixamoRootMotionWithPython_Assets/mixamo.py

@@ -0,0 +1,153 @@
+import unreal_engine as ue
+from unreal_engine.classes import SkeletalMesh, Skeleton, AnimSequence, AnimSequenceFactory
+from unreal_engine import FTransform, FRawAnimSequenceTrack, FQuat
+from unreal_engine import SWindow, SObjectPropertyEntryBox
+
+class DialogException(Exception):
+    def __init__(self, message):
+        ue.message_dialog_open(0, message)
+
+class RootMotionFixer:
+
+   
+    def add_root_to_skeleton(self, mesh, bone='root'):
+        base_path = mesh.get_path_name()
+        new_path = ue.create_modal_save_asset_dialog('Choose destination path', ue.get_path(base_path), ue.get_base_filename(base_path) + '_rooted')
+        if not new_path:
+            raise DialogException('Please specify a new path for the Skeletal Mesh copy')
+        package_name = ue.object_path_to_package_name(new_path)
+        object_name = ue.get_base_filename(new_path)
+        # the last True allows for overwrites
+        new_mesh = mesh.duplicate(package_name, object_name, True)
+
+        # generate a new skeleton
+        new_skel = self.build_new_skeleton(mesh.Skeleton, object_name + '_Skeleton', bone)
+        # save the new skeleton in the same package directory of the new skeletal mesh
+        new_skel.save_package(package_name)
+
+        # assign the new skeleton to the new mesh
+        new_mesh.skeletal_mesh_set_skeleton(new_skel)
+
+        new_skel.save_package()
+
+        self.fix_bones_influences(new_mesh, mesh.Skeleton)
+
+        new_mesh.save_package()
+
+    def build_new_skeleton(self, skeleton, name, root):
+        new_skel = Skeleton(name)
+        new_skel.skeleton_add_bone(root, -1, FTransform())
+        for index in range(0, skeleton.skeleton_bones_get_num()):
+            bone_name = skeleton.skeleton_get_bone_name(index)
+            bone_parent = skeleton.skeleton_get_parent_index(index)
+            bone_transform = skeleton.skeleton_get_ref_bone_pose(index)
+            if bone_parent == -1:
+                bone_parent_name = root
+            else:
+                bone_parent_name = skeleton.skeleton_get_bone_name(bone_parent)
+            new_bone_parent = new_skel.skeleton_find_bone_index(bone_parent_name)
+            new_skel.skeleton_add_bone(bone_name, new_bone_parent, bone_transform)
+        return new_skel
+
+    def get_updated_bone_index(self, old_skeleton, new_skeleton, old_bone_map, new_bone_map, index):
+
+        # get the skeleton bone_id from the map
+        true_bone_id = old_bone_map[index]
+
+        # get the bone name
+        bone_name = old_skeleton.skeleton_get_bone_name(true_bone_id)
+
+        # get the new index
+        new_bone_id = new_skeleton.skeleton_find_bone_index(bone_name)
+
+        # check if a new mapping is available
+        if new_bone_id in new_bone_map:
+            return new_bone_map.index(new_bone_id)
+
+        new_bone_map.append(new_bone_id)
+        return len(new_bone_map)-1
+
+    def fix_bones_influences(self, mesh, old_skeleton):
+        vertices = mesh.skeletal_mesh_get_soft_vertices()
+        new_vertices = []
+        old_bone_map = mesh.skeletal_mesh_get_bone_map()
+        new_bone_map = []
+
+        for vertex in vertices:
+            bone_ids = list(vertex.influence_bones)
+            for index, bone_id in enumerate(bone_ids):
+                if vertex.influence_weights[index] > 0:
+                    bone_ids[index] = self.get_updated_bone_index(old_skeleton, mesh.Skeleton, old_bone_map, new_bone_map, bone_id)
+            vertex.influence_bones = bone_ids
+            new_vertices.append(vertex)
+
+        # assign new vertices
+        mesh.skeletal_mesh_set_soft_vertices(new_vertices)
+        # add the new bone mapping
+        mesh.skeletal_mesh_set_bone_map(new_bone_map)
+
+        # specify which bones are active and required (ensure root is added to required bones)
+        mesh.skeletal_mesh_set_active_bone_indices(new_bone_map)
+        if 0 not in new_bone_map:
+            new_bone_map += [0]
+        mesh.skeletal_mesh_set_required_bones(new_bone_map)
+
+    def set_skeleton(self, asset_data):
+        self.choosen_skeleton = asset_data.get_asset()
+        self.window.request_destroy()
+
+    def split_hips(self, animation, bone='Hips'):
+        self.choosen_skeleton = None
+        # first ask for which skeleton to use:
+        self.window = SWindow(title='Choose your new Skeleton', modal=True, sizing_rule=1)(
+                     SObjectPropertyEntryBox(allowed_class=Skeleton, on_object_changed=self.set_skeleton)
+                 )
+        self.window.add_modal()
+        if not self.choosen_skeleton:
+            raise DialogException('Please specify a Skeleton for retargeting')
+
+        factory = AnimSequenceFactory()
+        factory.TargetSkeleton = self.choosen_skeleton
+        
+        base_path = animation.get_path_name()
+        package_name = ue.get_path(base_path)
+        object_name = ue.get_base_filename(base_path)
+
+        new_anim = factory.factory_create_new(package_name + '/' + object_name + '_rooted')
+
+        new_anim.NumFrames = animation.NumFrames
+        new_anim.SequenceLength = animation.SequenceLength
+
+        for index, name in enumerate(animation.AnimationTrackNames):
+            data = animation.get_raw_animation_track(index)
+            if name == bone:
+                # extract root motion
+                root_motion = [position - data.pos_keys[0] for position in data.pos_keys]
+
+                # remove root motion from original track
+                data.pos_keys = [data.pos_keys[0]]
+                new_anim.add_new_raw_track(name, data)
+
+                # create a new track (the root motion one)
+                root_data = FRawAnimSequenceTrack()
+                root_data.pos_keys = root_motion
+                # ensure empty rotations !
+                root_data.rot_keys = [FQuat()]
+        
+                 # add  the track
+                new_anim.add_new_raw_track('root', root_data)
+            else:
+                new_anim.add_new_raw_track(name, data)
+
+        new_anim.save_package()
+
+
+root_motion_fixer = RootMotionFixer()
+
+for uobject in ue.get_selected_assets():
+    if uobject.is_a(SkeletalMesh):
+        root_motion_fixer.add_root_to_skeleton(uobject)
+    elif uobject.is_a(AnimSequence):
+        root_motion_fixer.split_hips(uobject)
+    else:
+        raise DialogException('Only Skeletal Meshes are supported')