Blender-TexTools/op_color_select.py

import bpy
import bmesh
import operator
from mathutils import Vector
from collections import defaultdict
from math import pi

from . import utilities_color


class op(bpy.types.Operator):
    bl_idname = "uv.textools_color_select"
    bl_label = "Assign Color"
    bl_description = "Select faces by this color"
    bl_options = {'REGISTER', 'UNDO'}

    index: bpy.props.IntProperty(description="Color Index", default=0)

    @classmethod
    def poll(cls, context):
        if not bpy.context.active_object:
            return False

        if bpy.context.active_object not in bpy.context.selected_objects:
            return False

        # Allow only 1 object selected
        if len(bpy.context.selected_objects) != 1:
            return False

        if bpy.context.active_object.type != 'MESH':
            return False

        # Only in UV editor mode
        if bpy.context.area.type != 'IMAGE_EDITOR':
            return False

        return True

    def execute(self, context):
        select_color(self, context, self.index)
        return {'FINISHED'}


def select_color(self, context, index):
    print("Color select "+str(index))

    obj = bpy.context.active_object

    # Check for missing slots, materials,..
    if index >= len(obj.material_slots):
        self.report({'ERROR_INVALID_INPUT'},
                    "No material slot for color '{}' found".format(index))
        return

    if not obj.material_slots[index].material:
        self.report({'ERROR_INVALID_INPUT'},
                    "No material found for material slot '{}'".format(index))
        return

    if bpy.context.active_object.mode != 'EDIT':
        bpy.ops.object.mode_set(mode='EDIT')

    # Select faces
    bm = bmesh.from_edit_mesh(bpy.context.active_object.data)
    bpy.ops.mesh.select_all(action='DESELECT')
    for face in bm.faces:
        if face.material_index == index:
            face.select = True


bpy.utils.register_class(op)