mesh_auto_mirror.py

######################################################################################################
# A simple add-on to auto cut in two and mirror an object                                            #
# Actually partially uncommented (see further version)                                               #
# Author: Lapineige, Bookyakuno                                                                      #
# License: GPL v3                                                                                    #
######################################################################################################
# 2.8 update by Bookyakuno, meta-androcto

bl_info = {
    "name": "Auto Mirror",
    "description": "Super fast cutting and mirroring for mesh",
    "author": "Lapineige",
    "version": (2, 5, 2),
    "blender": (2, 80, 0),
    "location": "View 3D > Sidebar > Edit Tab > AutoMirror (panel)",
    "warning": "",
    "wiki_url": "https://docs.blender.org/manual/en/dev/addons/"
                "mesh/auto_mirror.html",
    "category": "Mesh"}


import bpy
from mathutils import Vector

import bmesh
import bpy
import collections
import mathutils
import math
from bpy_extras import view3d_utils
from bpy.types import (
        Operator,
        Menu,
        Panel,
        AddonPreferences,
        PropertyGroup,
        )
from bpy.props import (
        BoolProperty,
        EnumProperty,
        FloatProperty,
        IntProperty,
        PointerProperty,
        StringProperty,
        )


# Operator

class AlignVertices(Operator):

    """ Automatically cut an object along an axis """

    bl_idname = "object.align_vertices"
    bl_label = "Align Vertices on 1 Axis"

    @classmethod
    def poll(cls, context):
        obj = context.active_object
        return obj and obj.type == "MESH"

    def execute(self, context):
        automirror = context.scene.automirror

        bpy.ops.object.mode_set(mode = 'OBJECT')

        x1,y1,z1 = bpy.context.scene.cursor.location
        bpy.ops.view3d.snap_cursor_to_selected()

        x2,y2,z2 = bpy.context.scene.cursor.location

        bpy.context.scene.cursor.location[0], \
        bpy.context.scene.cursor.location[1], \
        bpy.context.scene.cursor.location[2]  = 0, 0, 0

        #Vertices coordinate to 0 (local coordinate, so on the origin)
        for vert in bpy.context.object.data.vertices:
            if vert.select:
                if automirror.axis == 'x':
                    axis = 0
                elif automirror.axis == 'y':
                    axis = 1
                elif automirror.axis == 'z':
                    axis = 2
                vert.co[axis] = 0

        bpy.context.scene.cursor.location = x2,y2,z2

        bpy.ops.object.origin_set(type='ORIGIN_CURSOR')

        bpy.context.scene.cursor.location = x1,y1,z1

        bpy.ops.object.mode_set(mode = 'EDIT')
        return {'FINISHED'}


class AutoMirror(bpy.types.Operator):
    """ Automatically cut an object along an axis """
    bl_idname = "object.automirror"
    bl_label = "AutoMirror"
    bl_options = {'REGISTER'} # 'UNDO' ?

    @classmethod
    def poll(cls, context):
        obj = context.active_object
        return obj and obj.type == "MESH"

    def draw(self, context):
        automirror = context.scene.automirror

        layout = self.layout
        if bpy.context.object and bpy.context.object.type == 'MESH':
            layout.prop(automirror, "axis", text = "Mirror axis")
            layout.prop(automirror, "orientation", text = "Orientation")
            layout.prop(automirror, "threshold", text = "Threshold")
            layout.prop(automirror, "toggle_edit", text = "Toggle edit")
            layout.prop(automirror, "cut", text = "Cut and mirror")
            if automirror.cut:
                layout.prop(automirror, "clipping", text = "Clipping")
                layout.prop(automirror, "mirror", text = "Apply mirror")

        else:
            layout.label(icon = "ERROR", text = "No mesh selected")

    def get_local_axis_vector(self, context, X, Y, Z, orientation):
        loc = context.object.location
        bpy.ops.object.mode_set(mode = "OBJECT") # Needed to avoid to translate vertices

        v1 = Vector((loc[0],loc[1],loc[2]))
        bpy.ops.transform.translate(value = (X*orientation, Y*orientation, Z*orientation),
                                        constraint_axis = ((X==1), (Y==1), (Z==1)),
                                        orient_type = 'LOCAL')
        v2 = Vector((loc[0],loc[1],loc[2]))
        bpy.ops.transform.translate(value = (-X*orientation, -Y*orientation, -Z*orientation),
                                        constraint_axis = ((X==1), (Y==1), (Z==1)),
                                        orient_type = 'LOCAL')

        bpy.ops.object.mode_set(mode="EDIT")
        return v2-v1

    def execute(self, context):
        automirror = context.scene.automirror

        X,Y,Z = 0,0,0

        if automirror.axis == 'x':
            X = 1
        elif automirror.axis == 'y':
            Y = 1
        elif automirror.axis == 'z':
            Z = 1

        current_mode = bpy.context.object.mode # Save the current mode

        if bpy.context.object.mode != "EDIT":
            bpy.ops.object.mode_set(mode = "EDIT") # Go to edit mode

        bpy.ops.mesh.select_all(action = 'SELECT') # Select all the vertices

        if automirror.orientation == 'positive':
            orientation = 1
        else:
            orientation = -1

        cut_normal = self.get_local_axis_vector(context, X, Y, Z, orientation)

        # Cut the mesh
        bpy.ops.mesh.bisect(
                plane_co = (
                bpy.context.object.location[0],
                bpy.context.object.location[1],
                bpy.context.object.location[2]
                ),
                plane_no = cut_normal,
                use_fill = False,
                clear_inner = automirror.cut,
                clear_outer = 0,
                threshold = automirror.threshold
                )

        bpy.ops.object.align_vertices() # Use to align the vertices on the origin, needed by the "threshold"

        if not automirror.toggle_edit:
            bpy.ops.object.mode_set(mode = current_mode) # Reload previous mode

        if automirror.cut:
            bpy.ops.object.modifier_add(type = 'MIRROR') # Add a mirror modifier
            bpy.context.object.modifiers[-1].use_axis[0] = X # Choose the axis to use, based on the cut's axis
            bpy.context.object.modifiers[-1].use_axis[1] = Y
            bpy.context.object.modifiers[-1].use_axis[2] = Z
            bpy.context.object.modifiers[-1].use_clip = automirror.Use_Matcap
            bpy.context.object.modifiers[-1].show_on_cage = automirror.show_on_cage
            if automirror.apply_mirror:
                bpy.ops.object.mode_set(mode = 'OBJECT')
                bpy.ops.object.modifier_apply(apply_as = 'DATA',
                                              modifier = bpy.context.object.modifiers[-1].name)
                if automirror.toggle_edit:
                    bpy.ops.object.mode_set(mode = 'EDIT')
                else:
                    bpy.ops.object.mode_set(mode = current_mode)

        return {'FINISHED'}


# Panel

class VIEW3D_PT_BisectMirror(Panel):
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_label = "Auto Mirror"
    bl_category = 'Edit'
    bl_options = {'DEFAULT_CLOSED'}

    def draw(self, context):
        automirror = context.scene.automirror

        layout = self.layout
        col = layout.column(align=True)

        layout = self.layout

        if bpy.context.object and bpy.context.object.type == 'MESH':
            layout.operator("object.automirror")
            layout.prop(automirror, "axis", text = "Mirror Axis", expand=True)
            layout.prop(automirror, "orientation", text = "Orientation")
            layout.prop(automirror, "threshold", text = "Threshold")
            layout.prop(automirror, "toggle_edit", text = "Toggle Edit")
            layout.prop(automirror, "cut", text = "Cut and Mirror")
            if bpy.context.scene.automirror.cut:
                layout.prop(automirror, "Use_Matcap", text = "Use Clip")
                layout.prop(automirror, "show_on_cage", text = "Editable")
                layout.prop(automirror, "apply_mirror", text = "Apply Mirror")

        else:
            layout.label(icon="ERROR", text = "No mesh selected")

# Properties
class AutoMirrorProps(PropertyGroup):
    axis : EnumProperty(
        items = [("x", "X", "", 1),
                 ("y", "Y", "", 2),
                 ("z", "Z", "", 3)],
        description="Axis used by the mirror modifier",
        )

    orientation : EnumProperty(
        items = [("positive", "Positive", "", 1),("negative", "Negative", "", 2)],
        description="Choose the side along the axis of the editable part (+/- coordinates)",
        )

    threshold : FloatProperty(
        default= 0.001, min= 0.001,
        description="Vertices closer than this distance are merged on the loopcut",
        )

    toggle_edit : BoolProperty(
        default= False,
        description="If not in edit mode, change mode to edit",
        )

    cut : BoolProperty(
        default= True,
        description="If enabeled, cut the mesh in two parts and mirror it. If not, just make a loopcut",
        )

    clipping : BoolProperty(
        default=True,
        )

    Use_Matcap : BoolProperty(
        default=True,
        description="Use clipping for the mirror modifier",
        )

    show_on_cage : BoolProperty(
        default=False,
        description="Enable to edit the cage (it's the classical modifier's option)",
        )

    apply_mirror : BoolProperty(
        description="Apply the mirror modifier (useful to symmetrise the mesh)",
        )


# Add-ons Preferences Update Panel

# Define Panel classes for updating
panels = (
        VIEW3D_PT_BisectMirror,
        )


def update_panel(self, context):
    message = ": 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 AutoMirrorAddonPreferences(AddonPreferences):
    # this must match the addon name, use '__package__'
    # when defining this in a submodule of a python package.
    bl_idname = __name__

    category: StringProperty(
            name = "Tab Category",
            description = "Choose a name for the category of the panel",
            default = "Edit",
            update = update_panel
            )

    def draw(self, context):
        layout = self.layout

        row = layout.row()
        col = row.column()
        col.label(text = "Tab Category:")
        col.prop(self, "category", text = "")

# define classes for registration
classes = (
    VIEW3D_PT_BisectMirror,
    AutoMirror,
    AlignVertices,
    AutoMirrorAddonPreferences,
    AutoMirrorProps,
    )


# registering and menu integration
def register():
    for cls in classes:
        bpy.utils.register_class(cls)

    bpy.types.Scene.automirror = PointerProperty(type = AutoMirrorProps)
    update_panel(None, bpy.context)

# unregistering and removing menus
def unregister():
    for cls in reversed(classes):
        bpy.utils.unregister_class(cls)

    del bpy.types.Scene.automirror

if __name__ == "__main__":
    register()