mesh_tiny_cad/BIX.py

   1 # SPDX-FileCopyrightText: 2016-2022 Blender Foundation
   2 #
   3 # SPDX-License-Identifier: GPL-2.0-or-later
   4
   5
   6 import bpy
   7 import bmesh
   8 from . import cad_module as cm
   9
  10
  11 def add_line_to_bisection(self):
  12
  13     obj = bpy.context.object
  14     me = obj.data
  15     bm = bmesh.from_edit_mesh(me)
  16
  17     bm.verts.ensure_lookup_table()
  18     bm.edges.ensure_lookup_table()
  19
  20     edges = [e for e in bm.edges if e.select and not e.hide]
  21
  22     if not len(edges) == 2:
  23         msg = "select two coplanar non parallel edges"
  24         self.report({"WARNING"}, msg)
  25         return
  26
  27     [[v1, v2], [v3, v4]] = [[v.co for v in e.verts] for e in edges]
  28     print('vectors found:\n', v1, '\n', v2, '\n', v3, '\n', v4)
  29
  30     dist1 = (v1 - v2).length
  31     dist2 = (v3 - v4).length
  32     bdist = min([dist1, dist2])
  33     edge1 = (v1, v2)
  34     edge2 = (v3, v4)
  35
  36     if not cm.test_coplanar(edge1, edge2):
  37         msg = "edges must be coplanar non parallel edges"
  38         self.report({"WARNING"}, msg)
  39         return
  40
  41     # get pt and pick fartest vertex from (projected) intersections
  42     pt = cm.get_intersection(edge1, edge2)
  43     far1 = v2 if (v1 - pt).length < (v2 - pt).length else v1
  44     far2 = v4 if (v3 - pt).length < (v4 - pt).length else v3
  45     # print('intersection: ', pt)
  46
  47     dex1 = far1 - pt
  48     dex2 = far2 - pt
  49     dex1 = dex1 * (bdist / dex1.length)
  50     dex2 = dex2 * (bdist / dex2.length)
  51     pt2 = pt + (dex1).lerp(dex2, 0.5)
  52     # print('bisector point:', pt2)
  53
  54     pt3 = pt2.lerp(pt, 2.0)
  55
  56     vec1 = bm.verts.new(pt2)
  57     vec2 = bm.verts.new(pt)
  58     vec3 = bm.verts.new(pt3)
  59     bm.edges.new((vec1, vec2))
  60     bm.edges.new((vec2, vec3))
  61     bmesh.update_edit_mesh(me)
  62     # print("done")
  63
  64
  65 class TCLineOnBisection(bpy.types.Operator):
  66     '''Generate the bisector of two selected edges'''
  67     bl_idname = 'tinycad.linetobisect'
  68     bl_label = 'BIX line to bisector'
  69     bl_options = {'REGISTER', 'UNDO'}
  70
  71     @classmethod
  72     def poll(cls, context):
  73         obj = context.active_object
  74         return all([obj is not None, obj.type == 'MESH', obj.mode == 'EDIT'])
  75
  76     def execute(self, context):
  77         add_line_to_bisection(self)
  78         return {'FINISHED'}