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Brecht Van Lommel authoredBrecht Van Lommel authored
mesh_helpers.py 8.28 KiB
# ##### BEGIN GPL LICENSE BLOCK #####
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# ##### END GPL LICENSE BLOCK #####
# <pep8-80 compliant>
# 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
me = obj.to_mesh(bpy.context.scene, True, 'PREVIEW')
bm = bmesh.new()
bm.from_mesh(me)
bpy.data.meshes.remove(me)
del bpy
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
is_editmode = (obj.mode == 'EDIT')
if is_editmode:
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
is_editmode = (obj.mode == 'EDIT')
if is_editmode:
bmesh.update_edit_mesh(me, True)
else:
bm.to_mesh(me)
# grr... cause an update
if me.vertices:
me.vertices[0].co[0] = me.vertices[0].co[0]
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
uniform_args = 0.0 + margin, 1.0 - margin
# for pradictable results
random.seed(f.index)
vecs = [v.co for v in f.verts]
for i 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
scene = context.scene
layer = context.view_layer
layer_collection = context.layer_collection
if layer_collection is None:
scene_collection = scene.master_collection.collections.new("")
layer_collection = layer.collections.link(scene_collection)
else:
scene_collection = layer_collection.collection
me_tmp = bpy.data.meshes.new(name="~temp~")
bm.to_mesh(me_tmp)
# bm.free() # delay free
obj_tmp = bpy.data.objects.new(name=me_tmp.name, object_data=me_tmp)
# base = scene.objects.link(obj_tmp)
scene_collection.objects.link(obj_tmp)
# Add new object to local view layer
# XXX28
'''
v3d = None
if context.space_data and context.space_data.type == 'VIEW_3D':
v3d = context.space_data
if v3d and v3d.local_view:
base.layers_from_view(context.space_data)
'''
scene.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)
# finished with bm
bm.free()
scene_collection.objects.unlink(obj_tmp)
bpy.data.objects.remove(obj_tmp)
bpy.data.meshes.remove(me_tmp)
scene.update()
return array.array('i', faces_error)
def object_merge(context, objects):
"""
Caller must remove.
"""
import bpy
def cd_remove_all_but_active(seq):
tot = len(seq)
if tot > 1:
act = seq.active_index
for i in range(tot - 1, -1, -1):
if i != act:
seq.remove(seq[i])
scene = context.scene
layer = context.view_layer
layer_collection = context.layer_collection
if layer_collection is None:
scene_collection = scene.master_collection.collections.new("")
layer_collection = layer.collections.link(scene_collection)
else:
scene_collection = layer_collection.collection
# deselect all
for obj in scene.objects:
obj.select_set('DESELECT')
# add empty object
mesh_base = bpy.data.meshes.new(name="~tmp~")
obj_base = bpy.data.objects.new(name="~tmp~", object_data=mesh_base)
scene_collection.objects.link(obj_base)
layer.objects.active = obj_base
obj_base.select_set('SELECT')
# loop over all meshes
for obj in objects:
if obj.type != 'MESH':
continue
# convert each to a mesh
mesh_new = obj.to_mesh(
depsgraph=context.depsgraph,
apply_modifiers=True,
)
# remove non-active uvs/vcols
cd_remove_all_but_active(mesh_new.vertex_colors)
cd_remove_all_but_active(mesh_new.uv_layers)
# join into base mesh
obj_new = bpy.data.objects.new(name="~tmp-new~", object_data=mesh_new)
base_new = scene_collection.objects.link(obj_new)
obj_new.matrix_world = obj.matrix_world
fake_context = context.copy()
fake_context["active_object"] = obj_base
fake_context["selected_editable_objects"] = [obj_base, obj_new]
bpy.ops.object.join(fake_context)
del base_new, obj_new
# remove object and its mesh, join does this
# scene_collection.objects.unlink(obj_new)
# bpy.data.objects.remove(obj_new)
bpy.data.meshes.remove(mesh_new)
scene.update()
# return new object
return obj_base
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