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#
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bl_info = {
    "name": "传递顶点顺序",
    "author": "Jose Conseco based on UV Transfer from MagicUV Nutti",
    "version": (2, 4),
    "blender": (4, 2, 0),
    "location": "侧边栏 (N) -> 工具面板",
    "description": "通过顶点位置或选定面传递顶点ID",
    "warning": "",
    "wiki_url": "",
    "category": "Object",
    "doc_url": "https://bartoszstyperek.gumroad.com/l/copy_verts_ids",
    }

from collections import OrderedDict

import bpy
import bmesh
from bpy.props import BoolProperty
from mathutils import kdtree, Vector


class CopyIDs():
    def __init__(self):
        self.transuv = ID_DATA()

class ID_DATA():
    face_vert_ids = []
    face_edge_ids = []
    faces_id = []
    face_loop_ids = []


class VOT_PT_CopyVertIds(bpy.types.Panel):
    bl_idname = "VOT_PT_copyvertids"
    bl_label = "传递顶点顺序"

    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = 'Tools'

    def draw(self, context):
        layout = self.layout
        if context.mode == 'OBJECT':
            layout.label(text = '编辑模式下有更多选项')
            layout.operator("object.vert_id_transfer_proximity")
            layout.operator("object.vert_id_transfer_uv")
            layout.operator("object.preview_vertex_order")
            layout.label(text="选中 -> 活动")

        elif context.mode == 'EDIT_MESH':
            layout.separator()
            layout.operator("object.copy_vert_id")
            layout.operator("object.paste_vert_id")
            layout.operator("object.copy_paste_vert_id")
            layout.operator("object.select_not_transfered_verts")
            layout.operator("object.preview_vertex_order")
            layout.label(text="选中 -> 活动")



class VOT_OT_TransferVertId(bpy.types.Operator):
    """通过顶点位置传递顶点ID"""
    bl_label = "使用位置传递ID"
    bl_idname = "object.vert_id_transfer_proximity"
    bl_description = "通过顶点位置传递顶点ID（适用于形状完全相同的网格）\n需要选择两个网格物体"
    bl_options = {'REGISTER'}

    delta: bpy.props.FloatProperty(name="误差", description="搜索距离", default=0.1, min=0, max=1, precision = 4)
    def execute(self, context):
        sourceObj = context.active_object
        TargetObjs = [obj for obj in context.selected_objects if obj!=sourceObj and obj.type=='MESH']

        if not TargetObjs:
            self.report({'ERROR'}, '你需要选择两个网格物体（源物体和接收顶点顺序的目标物体）！取消操作')
            return {'CANCELLED'}

        bm = bmesh.new()  # load mesh
        bm.from_mesh(sourceObj.data)
        src_obj_kd_verts = kdtree.KDTree(len(bm.verts))
        for i, v in enumerate(bm.verts):
            src_obj_kd_verts.insert(v.co, i)
        src_obj_kd_verts.balance()

        src_obj_kd_edges = kdtree.KDTree(len(bm.edges))
        for i, edge in enumerate(bm.edges):
            src_obj_kd_edges.insert((edge.verts[0].co+edge.verts[1].co)/2, i)
        src_obj_kd_edges.balance()

        src_obj_kd_faces = kdtree.KDTree(len(bm.faces))
        for i, f in enumerate(bm.faces):
            src_obj_kd_faces.insert(f.calc_center_median(), i)
        src_obj_kd_faces.balance()
        bm.free()
        processedVertsIdDict = {}
        processedEdgesIdDict = {}
        processedFacesIdDict = {}
        for target in TargetObjs:
            copiedCount = 0
            processedVertsIdDict.clear()
            bm = bmesh.new()  # load mesh
            bm.from_mesh(target.data)
            for vert in bm.verts:
                co, index, dist = src_obj_kd_verts.find(vert.co)
                if dist < self.delta:  # delta
                    copiedCount += 1
                    vert.index = index
                    processedVertsIdDict[vert] = index

            for edge in bm.edges:
                co, index, dist = src_obj_kd_edges.find((edge.verts[0].co+edge.verts[1].co)/2)
                if dist<self.delta:  #delta
                    copiedCount+=1
                    edge.index = index
                    processedEdgesIdDict[edge] = index

            for face in bm.faces:
                co, index, dist = src_obj_kd_faces.find(face.calc_center_median())
                if dist<self.delta:  #delta
                    copiedCount+=1
                    face.index = index
                    processedFacesIdDict[face] = index

            VOT_OT_PasteVertID.sortOtherVerts(processedVertsIdDict, processedEdgesIdDict, processedFacesIdDict, bm)
            bm.verts.sort()
            bm.edges.sort()
            bm.faces.sort()
            bm.to_mesh(target.data)
            bm.free()
            self.report({'INFO'}, '已粘贴 '+str(copiedCount)+' 个顶点ID')
        return {"FINISHED"}

class VOT_OT_TransferVertIdByUV(bpy.types.Operator):
    """通过UV传递顶点ID"""
    bl_label = "使用UV传递ID"
    bl_idname = "object.vert_id_transfer_uv"
    bl_description = "使用UV从选中物体传递顶点ID到活动物体（适用于形状不同但UV相同的网格）\n需要选择两个网格物体"
    bl_options = {'REGISTER'}

    delta: bpy.props.FloatProperty(name="误差", description="搜索距离", default=0.01, min=0, max=0.1, precision = 5)

    @staticmethod
    def find_face_uv_center(face: bmesh.types.BMFace, uv_layer):
        uv_ctr = Vector((0.0, 0.0))
        uv_cnt = 0
        for loop in face.loops:
            uv_ctr += loop[uv_layer].uv
            uv_cnt += 1

        # calculate winding value to better deal with multiple faces with the same UV center
        # (the main thing this is for is mirrored meshes that have the same UVs for both sides)
        winding_1: Vector = (face.loops[1][uv_layer].uv - face.loops[0][uv_layer].uv).to_3d()
        winding_2: Vector = (face.loops[2][uv_layer].uv - face.loops[0][uv_layer].uv).to_3d()
        # by not normalizing, it also serves to differentiate by face size centers that otherwise might match
        # will only be a z value since the input vectors were 2d on xy
        winding = winding_1.cross(winding_2)

        return (uv_ctr / uv_cnt).to_3d() + winding

    def execute(self, context):
        sourceObj = context.active_object
        TargetObjs = [obj for obj in context.selected_objects if obj!=sourceObj and obj.type=='MESH']

        if not TargetObjs:
            self.report({'ERROR'}, '你需要选择两个网格物体（源物体和接收顶点顺序的目标物体）！取消操作')
            return {'CANCELLED'}

        bm_src = bmesh.new()  # load mesh
        bm_src.from_mesh(sourceObj.data)
        bm_src.faces.ensure_lookup_table()

        src_obj_kd_faces = kdtree.KDTree(len(bm_src.faces))
        for f in bm_src.faces:
            src_obj_kd_faces.insert(self.find_face_uv_center(f, bm_src.loops.layers.uv.active), f.index)
        src_obj_kd_faces.balance()
        processedVertsIdDict = {}
        processedEdgesIdDict = {}
        processedFacesIdDict = {}
        for target in TargetObjs:
            processedVertsIdDict.clear()
            bm = bmesh.new()  # load mesh
            bm.from_mesh(target.data)
            for face in bm.faces:
                co, index, dist = src_obj_kd_faces.find(self.find_face_uv_center(face, bm.loops.layers.uv.active))
                if dist<self.delta:  #delta
                    face.index = index
                    processedFacesIdDict[face] = index
                    for loop_src, loop_dst in zip(bm_src.faces[index].loops, face.loops):
                        # will be copied over to the actual data later (so as to only be done once per vert/edge)
                        processedEdgesIdDict[loop_dst.edge] = loop_src.edge.index
                        loop_dst.edge.index = loop_src.edge.index
                        processedVertsIdDict[loop_dst.vert] = loop_src.vert.index
                        loop_dst.vert.index = loop_src.vert.index

            copiedCount = len(processedVertsIdDict)
            copiedCount += len(processedEdgesIdDict)
            copiedCount += len(processedFacesIdDict)

            VOT_OT_PasteVertID.sortOtherVerts(processedVertsIdDict, processedEdgesIdDict, processedFacesIdDict, bm)
            bm.verts.sort()
            bm.edges.sort()
            bm.faces.sort()
            bm.to_mesh(target.data)
            bm.free()
            self.report({'INFO'}, '已粘贴 '+str(copiedCount)+' 个顶点ID')
        bm_src.free()
        return {"FINISHED"}


class VOT_OT_CopyVertID(bpy.types.Operator):
    bl_idname = "object.copy_vert_id"
    bl_label = "复制顶点ID"
    bl_description = "通过拓扑复制顶点ID（需要选择两个面）\n网格形状可以不同，但拓扑必须相同"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):
        props = context.scene.copy_indices.transuv
        active_obj = context.active_object
        self.obj = active_obj
        bm = bmesh.from_edit_mesh(active_obj.data)
        bm.edges.ensure_lookup_table()
        bm.faces.ensure_lookup_table()
        color_layer = get_color_layer(bm)

        props.face_loop_ids.clear()
        props.face_vert_ids.clear()
        props.face_edge_ids.clear()
        props.faces_id.clear()

        # get selected faces
        active_face = bm.faces.active
        sel_faces = [face for face in bm.faces if face.select]
        if len(sel_faces) != 2:
            self.report({'WARNING'}, "必须选择两个面")
            return {'CANCELLED'}
        if not active_face or active_face not in sel_faces:
            self.report({'WARNING'}, "必须有一个活动面")
            return {'CANCELLED'}

        # parse all faces according to selection
        active_face_nor = active_face.normal.copy()
        all_sorted_faces = main_parse(self, sel_faces, active_face, active_face_nor)
        if all_sorted_faces:
            for face, face_data in all_sorted_faces.items():
                loops = face_data[0]
                verts = face_data[1]
                edges = face_data[2]
                props.face_loop_ids.append([loop.index for loop in loops])
                props.face_vert_ids.append([vert.index for vert in verts])
                props.face_edge_ids.append([e.index for e in edges])
                props.faces_id.append(face.index)

                for loop in loops:
                    loop[color_layer] = Vector((1,0,0,1))

        bmesh.update_edit_mesh(active_obj.data)
        activate_color_layer(active_obj)
        self.report({"INFO"}, "顶点顺序已复制。")
        return {'FINISHED'}


class VOT_OT_PasteVertID(bpy.types.Operator):
    bl_idname = "object.paste_vert_id"
    bl_label = "粘贴顶点ID"
    bl_description = (
        "通过拓扑粘贴顶点ID（需要选择两个与源物体拓扑匹配的面）\n"
        "网格形状可以不同，但拓扑必须相同"
    )
    bl_options = {'REGISTER', 'UNDO'}

    invert_normals: BoolProperty(name="反转法线", description="反转法线", default=False)

    @staticmethod
    def sortOtherVerts(processedVertsIdDict, preocessedEdgesIsDict, preocessedFaceIsDict, bm):
        """Prevet verts on other islands from being all shuffled"""
        # dicts instead of lists - faster search 4x?
        if len(bm.verts) == len(processedVertsIdDict) and len(bm.faces) == len(preocessedFaceIsDict):
            return #all verts, and faces were processed - > no other Islands -> quit

        def fix_islands(processed_items, bm_element): #face, verts, or edges
            processedItems = {item: id for (item, id) in processed_items.items()}  # dicts instead of lists
            processedIDs = {id: 1 for (item, id) in processed_items.items()}  # dicts instead of lists

            notProcessedItemsIds = {ele.index: 1 for ele in bm_element if ele not in processedItems}  # it will have duplicated ids from processedIDs that have to be

            spareIDS = [i for i in range(len(bm_element)) if (i not in processedIDs and i not in notProcessedItemsIds)]

            notProcessedElements = [item for item in bm_element if item not in processedItems]
            for item in notProcessedElements:
                if item.index in processedIDs:  # if duplicated id found in not processed verts
                    item.index = spareIDS.pop(0)  # what if list is empty??

        fix_islands(processedVertsIdDict, bm.verts)
        fix_islands(preocessedEdgesIsDict, bm.edges)
        fix_islands(preocessedFaceIsDict, bm.faces)


    def execute(self, context):
        props = context.scene.copy_indices.transuv
        active_obj = context.active_object
        bm = bmesh.from_edit_mesh(active_obj.data)
        bm.edges.ensure_lookup_table()
        bm.faces.ensure_lookup_table()
        color_layer = get_color_layer(bm)

        # get selection history
        all_sel_faces = [
            e for e in bm.select_history
            if isinstance(e, bmesh.types.BMFace) and e.select]
        if len(all_sel_faces) % 2 != 0:
            self.report({'WARNING'}, "必须选择两个面")
            return {'CANCELLED'}

        # parse selection history
        loopID_dict = {}
        vertID_dict = {}
        edgeID_dict = {}
        faceID_dict = {}
        for i, _ in enumerate(all_sel_faces):
            if (i == 0) or (i % 2 == 0):
                continue
            sel_faces = [all_sel_faces[i - 1], all_sel_faces[i]]
            active_face = all_sel_faces[i]

            # parse all faces according to selection history
            active_face_nor = active_face.normal.copy()
            if self.invert_normals:
                active_face_nor.negate()
            all_sorted_faces = main_parse(self, sel_faces, active_face, active_face_nor)
            # ipdb.set_trace()
            if all_sorted_faces:
                # check amount of copied/pasted faces
                if len(all_sorted_faces) != len(props.face_vert_ids):
                    self.report(
                        {'WARNING'},
                        "网格的面数量不同"
                    )
                    return {'FINISHED'}


                for j,(face, face_data) in enumerate(all_sorted_faces.items()):
                    loop_ids_cache = props.face_loop_ids[j]
                    vert_ids_cache = props.face_vert_ids[j]
                    edge_ids_cache = props.face_edge_ids[j]
                    face_id_cache = props.faces_id[j]

                    # check amount of copied/pasted verts
                    if len(vert_ids_cache) != len(face_data[1]):
                        bpy.ops.mesh.select_all(action='DESELECT')
                        # select problematic face
                        list(all_sorted_faces.keys())[j].select = True
                        self.report(
                            {'WARNING'},
                            "面的顶点数量不同"
                        )
                        return {'FINISHED'}

                    for k, vert in enumerate(face_data[1]):
                        vert.index = vert_ids_cache[k]  #index
                        vertID_dict[vert] = vert.index

                    for k, loop in enumerate(face_data[0]):
                        loop.index = loop_ids_cache[k]  #index
                        loop[color_layer] = Vector((0,1,0,1))
                        loopID_dict[loop] = loop.index

                    face.index = face_id_cache
                    faceID_dict[face] = face_id_cache

                    for k, edge in enumerate(face_data[2]): #edges
                        edge.index = edge_ids_cache[k]  # index
                        edgeID_dict[edge] = edge.index

        self.sortOtherVerts(vertID_dict, edgeID_dict, faceID_dict, bm)
        #? does not exist bm.loops.sort()
        bm.verts.sort()
        bm.edges.sort()
        bm.faces.sort()

        #! !!! for faces in bm.fa
        bmesh.update_edit_mesh(active_obj.data)
        activate_color_layer(active_obj)
        self.report({"INFO"}, "顶点顺序已粘贴。")
        return {'FINISHED'}


class VOT_OT_CopyPasteVertID(bpy.types.Operator):
    bl_idname = "object.copy_paste_vert_id"
    bl_label = "复制并粘贴顶点ID"
    bl_description = (
        "从选中物体复制顶点顺序到活动物体。"
        "两个物体都应处于编辑模式并选择两个相似的面"
    )
    bl_options = {'REGISTER', 'UNDO'}

    @classmethod
    def poll(cls, context):
        selected_objects = context.selected_objects
        if len(selected_objects) != 2 or any(obj.mode != "EDIT" for obj in selected_objects):
            cls.poll_message_set("必须选择两个物体，且都需要处于编辑模式")
            return False
        return True

    def execute(self, context):
        selected_objects = context.selected_objects
        target_obj = context.active_object
        source_obj = next(obj for obj in selected_objects if obj != target_obj)

        with context.temp_override(active_object=source_obj):
            bpy.ops.object.copy_vert_id()

        with context.temp_override(active_object=target_obj):
            bpy.ops.object.paste_vert_id()

        return {"FINISHED"}

def main_parse(self, sel_faces, active_face, active_face_nor):
    all_sorted_faces = OrderedDict()  # This is the main stuff

    used_verts = set()
    used_edges = set()

    faces_to_parse = []

    # get shared edge of two faces
    cross_edges = []
    for edge in active_face.edges:
        if edge in sel_faces[0].edges and edge in sel_faces[1].edges:
            cross_edges.append(edge)

    # parse two selected faces
    if cross_edges and len(cross_edges) == 1:
        shared_edge = cross_edges[0]
        vert1 = None
        vert2 = None

        dot_n = active_face_nor.normalized()
        edge_vec_1 = (shared_edge.verts[1].co - shared_edge.verts[0].co)
        edge_vec_len = edge_vec_1.length
        edge_vec_1 = edge_vec_1.normalized()

        af_center = active_face.calc_center_median()
        af_vec = shared_edge.verts[0].co + (edge_vec_1 * (edge_vec_len * 0.5))
        af_vec = (af_vec - af_center).normalized()

        if af_vec.cross(edge_vec_1).dot(dot_n) > 0:
            vert1 = shared_edge.verts[0]
            vert2 = shared_edge.verts[1]
        else:
            vert1 = shared_edge.verts[1]
            vert2 = shared_edge.verts[0]

        # get active face stuff and uvs
        # ipdb.set_trace()
        face_stuff = get_other_verts_edges(active_face, vert1, vert2, shared_edge)
        all_sorted_faces[active_face] = face_stuff
        used_verts.update(active_face.verts)
        used_edges.update(active_face.edges)

        # get first selected face stuff and uvs as they share shared_edge
        second_face = sel_faces[0]
        if second_face is active_face:
            second_face = sel_faces[1]
        face_stuff = get_other_verts_edges(second_face, vert1, vert2, shared_edge)
        all_sorted_faces[second_face] = face_stuff
        used_verts.update(second_face.verts)
        used_edges.update(second_face.edges)

        # first Grow
        faces_to_parse.append(active_face)
        faces_to_parse.append(second_face)

    else:
        self.report({'WARNING'}, "两个面应该共享一条边")
        return None

    # parse all faces
    while True:
        new_parsed_faces = []

        if not faces_to_parse:
            break
        for face in faces_to_parse:
            face_stuff = all_sorted_faces.get(face)
            new_faces = parse_faces(face, face_stuff, used_verts, used_edges, all_sorted_faces)
            if new_faces == 'CANCELLED':
                self.report({'WARNING'}, "超过2个面共享边")
                return None

            new_parsed_faces += new_faces
        faces_to_parse = new_parsed_faces

    return all_sorted_faces


def parse_faces(check_face, face_stuff, used_verts, used_edges, all_sorted_faces):
    """recurse faces around the new_grow only"""

    new_shared_faces = []
    for sorted_edge in face_stuff[2]:
        shared_faces = sorted_edge.link_faces
        if shared_faces:
            if len(shared_faces) > 2:
                bpy.ops.mesh.select_all(action='DESELECT')
                for face_sel in shared_faces:
                    face_sel.select = True
                shared_faces = []
                return 'CANCELLED'

            clear_shared_faces = get_new_shared_faces(check_face, sorted_edge, shared_faces, all_sorted_faces.keys())
            if clear_shared_faces:
                shared_face = clear_shared_faces[0]
                # get vertices of the edge
                vert1 = sorted_edge.verts[0]
                vert2 = sorted_edge.verts[1]

                if face_stuff[1].index(vert1) > face_stuff[1].index(vert2):
                    vert1 = sorted_edge.verts[1]
                    vert2 = sorted_edge.verts[0]

                new_face_stuff = get_other_verts_edges(shared_face, vert1, vert2, sorted_edge)
                all_sorted_faces[shared_face] = new_face_stuff
                used_verts.update(shared_face.verts)
                used_edges.update(shared_face.edges)

                new_shared_faces.append(shared_face)

    return new_shared_faces


def get_new_shared_faces(orig_face, shared_edge, check_faces, used_faces):
    shared_faces = []

    for face in check_faces:
        is_shared_edge = shared_edge in face.edges
        not_used = face not in used_faces
        not_orig = face is not orig_face
        not_hide = face.hide is False
        if is_shared_edge and not_used and not_orig and not_hide:
            shared_faces.append(face)

    return shared_faces


def get_other_verts_edges(face, vert1, vert2, first_edge):
    face_edges = [first_edge]
    face_verts = [vert1, vert2]

    other_edges = [edge for edge in face.edges if edge not in face_edges]

    face_loops = []  # ! move to vert processing above? To maintain order ids?
    def add_vert_loop(ver): #add vert link_loops
        for loop in ver.link_loops:
            if loop.face == face:
                face_loops.append(loop)
                break

    add_vert_loop(vert1) #add loops in same order as verts
    add_vert_loop(vert2)
    for _ in range(len(other_edges)):
        found_edge = None
        # get sorted verts and edges
        for edge in other_edges:
            if face_verts[-1] in edge.verts:
                other_vert = edge.other_vert(face_verts[-1])

                if other_vert not in face_verts:
                    face_verts.append(other_vert)
                    add_vert_loop(other_vert)

                found_edge = edge
                if found_edge not in face_edges:
                    face_edges.append(edge)
                break

        other_edges.remove(found_edge)

    return [face_loops, face_verts, face_edges]


panels = (
    VOT_PT_CopyVertIds,
)

def update_panel(self, context):
    message = "Vertex Order: Updating Panel locations has failed"
    try:
        for panel in panels:
            if "bl_rna" in panel.__dict__:
                bpy.utils.unregister_class(panel)

        for panel in panels:
            panel.bl_category = context.preferences.addons[__name__].preferences.category
            bpy.utils.register_class(panel)

    except Exception as e:
        print("\n[{}]\n{}\n\nError:\n{}".format(__name__, message, e))
        pass


class WertOrderPreferences(bpy.types.AddonPreferences):
    # this must match the addon name, use '__package__'
    # when defining this in a submodule of a python package.
    bl_idname = __name__

    category: bpy.props.StringProperty( name="标签类别", description="为面板类别选择一个名称", default="Tools", update=update_panel )

    def draw(self, context):
        layout = self.layout
        row = layout.row()
        col = row.column()
        col.label(text="标签类别:")
        col.prop(self, "category", text="")


def get_color_layer(bm):
    color_layer = bm.loops.layers.color.get("VTX_TRANSFER", None)
    if not color_layer:
        color_layer = bm.loops.layers.color.new("VTX_TRANSFER")
    return color_layer

def activate_color_layer(obj):
    obj.data.vertex_colors["VTX_TRANSFER"].active = True

class VOT_OT_SelectNotTransfered(bpy.types.Operator):
    bl_idname = "object.select_not_transfered_verts"
    bl_label = "选择未传递的顶点"
    bl_description = "选择所有尚未传递顶点顺序的面"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):
        active_obj = context.active_object
        self.obj = active_obj
        bm = bmesh.from_edit_mesh(active_obj.data)
        color_layer = get_color_layer(bm)
        something_left = False

        for face in bm.faces:
            for loop in face.loops:
                if loop[color_layer].z > 0.01:
                    face.select = True
                    something_left = True
                    break
            else:
                face.select = False

        bmesh.update_edit_mesh(active_obj.data)
        activate_color_layer(active_obj)
        if something_left:
            self.report({"INFO"}, "已选择面")
        else:
            self.report({"INFO"}, "顶点顺序传递完成，没有可选择的内容")

        return {"FINISHED"}

class VOT_OT_PreviewVertexOrder(bpy.types.Operator):
    bl_idname = "object.preview_vertex_order"
    bl_label = "预览顶点顺序"
    bl_description = "通过从选中物体在活动物体上创建形态键来预览顶点顺序"
    bl_options = {'REGISTER', 'UNDO'}

    @classmethod
    def poll(cls, context):
        if not len(context.selected_objects) == 2:
            cls.poll_message_set("需要选择2个物体")
            return False
        return True

    def execute(self, context):
        selected_objects = context.selected_objects
        target_obj = context.active_object
        source_obj = next(obj for obj in selected_objects if obj != target_obj)

        if bpy.context.mode != "OBJECT":
            bpy.ops.object.mode_set(mode = "OBJECT")

        shape_keys = target_obj.data.shape_keys
        if not shape_keys:
            target_obj.shape_key_add(name="Basis")
            shape_keys = target_obj.data.shape_keys
        key_blocks = shape_keys.key_blocks
        # if we already have that shape key, then we remove it first
        if "VTX_TRANSFER" in key_blocks:
            previous_shape_key = key_blocks["VTX_TRANSFER"]
            shape_key_index = key_blocks[:].index(previous_shape_key)
            current_shape_key_index = target_obj.active_shape_key_index
            target_obj.active_shape_key_index = shape_key_index
            bpy.ops.object.shape_key_remove()
            target_obj.active_shape_key_index = current_shape_key_index

        bpy.ops.object.join_shapes()
        shape_key = key_blocks[:][-1]
        shape_key.name = 'VTX_TRANSFER'
        shape_key.value = 1.0
        return {"FINISHED"}


classes = (
    WertOrderPreferences,
    VOT_OT_TransferVertId,
    VOT_OT_TransferVertIdByUV,
    VOT_OT_CopyVertID,
    VOT_OT_PasteVertID,
    VOT_OT_SelectNotTransfered,
    VOT_PT_CopyVertIds,
    VOT_OT_CopyPasteVertID,
    VOT_OT_PreviewVertexOrder
)

def register():
    bpy.types.Scene.copy_indices = CopyIDs()
    # bpy.ops.wm.addon_enable(module="space_view3d_copy_attributes")

    from bpy.utils import register_class
    for cls in classes:
        register_class(cls)
    update_panel(None, bpy.context)


def unregister():
    from bpy.utils import unregister_class
    for cls in reversed(classes):
        unregister_class(cls)
    del bpy.types.Scene.copy_indices

if __name__ == "__main__":
    register()