1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
# SPDX-License-Identifier: GPL-2.0-or-later
# Generic helper functions, to be used by any modules.
import bmesh
def bmesh_copy_from_object(obj, transform=True, triangulate=True, apply_modifiers=False):
"""Returns a transformed, triangulated copy of the mesh"""
assert obj.type == 'MESH'
if apply_modifiers and obj.modifiers:
import bpy
depsgraph = bpy.context.evaluated_depsgraph_get()
obj_eval = obj.evaluated_get(depsgraph)
me = obj_eval.to_mesh()
bm = bmesh.new()
bm.from_mesh(me)
obj_eval.to_mesh_clear()
else:
me = obj.data
if obj.mode == 'EDIT':
bm_orig = bmesh.from_edit_mesh(me)
bm = bm_orig.copy()
else:
bm = bmesh.new()
bm.from_mesh(me)
# TODO. remove all customdata layers.
# would save ram
if transform:
bm.transform(obj.matrix_world)
if triangulate:
bmesh.ops.triangulate(bm, faces=bm.faces)
return bm
def bmesh_from_object(obj):
"""Object/Edit Mode get mesh, use bmesh_to_object() to write back."""
me = obj.data
if obj.mode == 'EDIT':
bm = bmesh.from_edit_mesh(me)
else:
bm = bmesh.new()
bm.from_mesh(me)
return bm
def bmesh_to_object(obj, bm):
"""Object/Edit Mode update the object."""
me = obj.data
if obj.mode == 'EDIT':
bmesh.update_edit_mesh(me, loop_triangles=True)
else:
bm.to_mesh(me)
me.update()
def bmesh_calc_area(bm):
"""Calculate the surface area."""
return sum(f.calc_area() for f in bm.faces)
def bmesh_check_self_intersect_object(obj):
"""Check if any faces self intersect returns an array of edge index values."""
import array
import mathutils
if not obj.data.polygons:
return array.array('i', ())
bm = bmesh_copy_from_object(obj, transform=False, triangulate=False)
tree = mathutils.bvhtree.BVHTree.FromBMesh(bm, epsilon=0.00001)
overlap = tree.overlap(tree)
faces_error = {i for i_pair in overlap for i in i_pair}
return array.array('i', faces_error)
def bmesh_face_points_random(f, num_points=1, margin=0.05):
import random
from random import uniform
# for pradictable results
random.seed(f.index)
uniform_args = 0.0 + margin, 1.0 - margin
vecs = [v.co for v in f.verts]
for _ in range(num_points):
u1 = uniform(*uniform_args)
u2 = uniform(*uniform_args)
u_tot = u1 + u2
if u_tot > 1.0:
u1 = 1.0 - u1
u2 = 1.0 - u2
side1 = vecs[1] - vecs[0]
side2 = vecs[2] - vecs[0]
yield vecs[0] + u1 * side1 + u2 * side2
def bmesh_check_thick_object(obj, thickness):
import array
import bpy
# Triangulate
bm = bmesh_copy_from_object(obj, transform=True, triangulate=False)
# map original faces to their index.
face_index_map_org = {f: i for i, f in enumerate(bm.faces)}
ret = bmesh.ops.triangulate(bm, faces=bm.faces)
face_map = ret["face_map"]
del ret
# old edge -> new mapping
# Convert new/old map to index dict.
# Create a real mesh (lame!)
context = bpy.context
layer = context.view_layer
scene_collection = context.layer_collection.collection
me_tmp = bpy.data.meshes.new(name="~temp~")
bm.to_mesh(me_tmp)
obj_tmp = bpy.data.objects.new(name=me_tmp.name, object_data=me_tmp)
scene_collection.objects.link(obj_tmp)
layer.update()
ray_cast = obj_tmp.ray_cast
EPS_BIAS = 0.0001
faces_error = set()
bm_faces_new = bm.faces[:]
for f in bm_faces_new:
no = f.normal
no_sta = no * EPS_BIAS
no_end = no * thickness
for p in bmesh_face_points_random(f, num_points=6):
# Cast the ray backwards
p_a = p - no_sta
p_b = p - no_end
p_dir = p_b - p_a
ok, _co, no, index = ray_cast(p_a, p_dir, distance=p_dir.length)
if ok:
# Add the face we hit
for f_iter in (f, bm_faces_new[index]):
# if the face wasn't triangulated, just use existing
f_org = face_map.get(f_iter, f_iter)
f_org_index = face_index_map_org[f_org]
faces_error.add(f_org_index)
bm.free()
scene_collection.objects.unlink(obj_tmp)
bpy.data.objects.remove(obj_tmp)
bpy.data.meshes.remove(me_tmp)
layer.update()
return array.array('i', faces_error)
def face_is_distorted(ele, angle_distort):
no = ele.normal
angle_fn = no.angle
for loop in ele.loops:
loopno = loop.calc_normal()
if loopno.dot(no) < 0.0:
loopno.negate()
if angle_fn(loopno, 1000.0) > angle_distort:
return True
return False
|
