Differential D283 Diff 2755 io_export_paper_model.py

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io_export_paper_model.py

# -- coding: utf-8 --		# -- coding: utf-8 --
# ##### BEGIN GPL LICENSE BLOCK #####		# ##### BEGIN GPL LICENSE BLOCK #####
#		#
# This program is free software; you can redistribute it and/or		# This program is free software: you can redistribute it and/or modify
# modify it under the terms of the GNU General Public License		# it under the terms of the GNU General Public License as published by
# as published by the Free Software Foundation; either version 2		# the Free Software Foundation, either version 2 of the License, or
# of the License, or (at your option) any later version.		# (at your option) any later version.
#		#
# This program is distributed in the hope that it will be useful,		# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of		# but without any warranty; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the		# merchantability or fitness for a particular purpose. See the
# GNU General Public License for more details.		# GNU General Public License for more details.
#		#
# You should have received a copy of the GNU General Public License		# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,		# along with this program. If not, see <http://www.gnu.org/licenses/>.
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#		#
# ##### END GPL LICENSE BLOCK #####		# ##### END GPL LICENSE BLOCK #####

#### FIXME:
# Island.join: size limit: bounding box: rightmost vertex must be explicitly calculated
# Island.join: is_below: using assertion to do necessary calculations is illegal

#### TODO:		#### TODO:
# sanitize the constructors so that they don't edit their parent object		# sanitize the constructors so that they don't edit their parent object
# apply island rotation and position before exporting, to simplify things		# apply island rotation and position before exporting, to simplify things
# rename verts -> vertices, edge.vect -> edge.vector		# rename verts -> vertices, edge.vect -> edge.vector
# SVG object doesn't need a 'pure_net' argument in constructor		# SVG object doesn't need a 'pure_net' argument in constructor
# maybe Island would do with a list of points as well, set of vertices makes things more complicated		# maybe Island would do with a list of points as well, set of vertices makes things more complicated
# why does UVVertex copy its position in constructor?		# why does UVVertex copy its position in constructor?
# is it necessary to keep island.boundary_sorted sorted? Could save some time		# is it necessary to keep island.boundary sorted? Could save some time
# remember selected objects before baking, except selected to active		# remember selected objects before baking, except selected to active
# islands with default names should be excluded while matching		# islands with default names should be excluded while matching
# add 'estimated number of pages' to the export UI		# add 'estimated number of pages' to the export UI
		# profile QuickSweepline vs. BruteSweepline with/without blist: for which nets is it faster?
		# rotate islands to minimize area -- and change that only if necessary to fill the page size

# check conflicts in island naming and either:		# check conflicts in island naming and either:
# * append a number to the conflicting names or		# * append a number to the conflicting names or
# * enumerate faces uniquely within all islands of the same name (requires a check that both label and abbr. equals)		# * enumerate faces uniquely within all islands of the same name (requires a check that both label and abbr. equals)


bl_info = {		bl_info = {
"name": "Export Paper Model",		"name": "Export Paper Model",
"author": "Addam Dominec",		"author": "Addam Dominec",
"version": (0, 9),		"version": (0, 9),
"blender": (2, 66, 0),		"blender": (2, 70, 0),
"location": "File > Export > Paper Model",		"location": "File > Export > Paper Model",
"warning": "",		"warning": "",
"description": "Export printable net of the active mesh",		"description": "Export printable net of the active mesh",
"category": "Import-Export",		"category": "Import-Export",
"wiki_url": "http://wiki.blender.org/index.php/Extensions:2.6/Py/" \		"wiki_url": "http://wiki.blender.org/index.php/Extensions:2.6/Py/"
"Scripts/Import-Export/Paper_Model",		"Scripts/Import-Export/Paper_Model",
"tracker_url": "https://projects.blender.org/tracker/index.php?" \		"tracker_url": "https://projects.blender.org/tracker/index.php?"
"func=detail&aid=22417&group_id=153&atid=467"}		"func=detail&aid=22417&group_id=153&atid=467"
		}

"""		"""

Additional links:		Additional links:
e-mail: adominec {at} gmail {dot} com		e-mail: adominec {at} gmail {dot} com

"""		"""
import bpy, bgl		import bpy
		import bgl
import mathutils as M		import mathutils as M
from re import compile as re_compile		from re import compile as re_compile
from itertools import chain		from itertools import chain
		from math import pi

try:		try:
		campbellbartonUnsubmitted Not Done Inline Actions no need for try here campbellbarton: no need for try here
from math import pi		import os.path as os_path
except ImportError:		except ImportError:
pi = 3.141592653589783		os_path = None

		campbellbartonUnsubmitted Not Done Inline Actions whats `blist` ? campbellbarton: whats `blist` ?
		emuAuthorUnsubmitted Not Done Inline Actions a type similar to list, implemented using a search tree. It can insert at any position in O(log n). https://pypi.python.org/pypi/blist/1.3.4 emu: a type similar to list, implemented using a search tree. It can insert at any position in O(log…
try:		try:
from blist import blist		from blist import blist
except ImportError:		except ImportError:
blist = list		blist = list

default_priority_effect={		default_priority_effect = {
'CONVEX': 0.5,		'CONVEX': 0.5,
'CONCAVE': 1,		'CONCAVE': 1,
'LENGTH': -0.05}		'LENGTH': -0.05
		}

		campbellbartonUnsubmitted Not Done Inline Actions this could be a regular function campbellbarton: this could be a regular function
strf="{:.3f}".format
first_letters = lambda text: (text[match.start()] for match in first_letters.pattern.finditer(text))
first_letters.pattern = re_compile("(?<!\w)[\w]")

def sign(a):		def first_letters(text):
"""Return -1 for negative numbers, 1 for positive and 0 for zero."""		"""Iterator over the first letter of each word"""
return -1 if a < 0 else 1 if a > 0 else 0		for match in first_letters.pattern.finditer(text):
		yield text[match.start()]
def vectavg(vectlist):		first_letters.pattern = re_compile("(?<!\w)[\w]")
"""Vector average of given list."""
if not vectlist:
return M.Vector((0,0))
last = vectlist[0]
if type(last) is Vertex:
vect_sum = last.co.copy() #keep the dimensions
vect_sum.zero()
for vect in vectlist:
vect_sum += vect.co
else:
vect_sum = last.copy() #keep the dimensions
vect_sum.zero()
for vect in vectlist:
vect_sum += vect
return vect_sum / len(vectlist)

def angle2d(direction, unit_vector = M.Vector((1,0))):
"""Get the view angle of point from origin."""
if direction.length_squared == 0:
raise ValueError("Zero vector does not define an angle")
if len(direction) >= 3: #for 3d vectors
direction = direction.to_2d()
angle = unit_vector.angle_signed(direction)
return angle

def cross_product(v1, v2):
return v1.xv2.y - v1.yv2.x

def pairs(sequence):		def pairs(sequence):
"""Generate consecutive pairs throughout the given sequence; at last, it gives elements last, first."""		"""Generate consecutive pairs throughout the given sequence; at last, it gives elements last, first."""
i=iter(sequence)		i = iter(sequence)
previous=first=next(i)		previous = first = next(i)
for this in i:		for this in i:
yield previous, this		yield previous, this
previous=this		previous = this
yield this, first		yield this, first


def argmax_pair(array, key):		def argmax_pair(array, key):
		"""Find an (unordered) pair of indices that maximize the given function"""
l = len(array)		l = len(array)
mi, mj, m = None, None, None		mi, mj, m = None, None, None
for i in range(l):		for i in range(l):
for j in range(i+1, l):		for j in range(i+1, l):
k = key(array[i], array[j])		k = key(array[i], array[j])
if not m or k > m:		if not m or k > m:
mi, mj, m = i, j, k		mi, mj, m = i, j, k
return mi, mj		return mi, mj


def fitting_matrix(v1, v2):		def fitting_matrix(v1, v2):
"""Matrix that rotates v1 to the same direction as v2"""		"""Get a matrix that rotates v1 to the same direction as v2"""
return (1/v1.length_squared)*M.Matrix((		return (1 / v1.length_squared) * M.Matrix((
		campbellbartonUnsubmitted Not Done Inline Actions our API should be able to do this. campbellbarton: our API should be able to do this.
		emuAuthorUnsubmitted Not Done Inline Actions sure, as v1.to_3d().cross(v2.to_3d()).z I did some profiling and this appears to be faster. It is one of the most often called functions in the script. emu: sure, as v1.to_3d().cross(v2.to_3d()).z I did some profiling and this appears to be faster. It…
		campbellbartonUnsubmitted Not Done Inline Actions Update, v1.cross(v2) now works for 2d vectors. https://developer.blender.org/rB06b6cd83459713ef5c00f705f6cdf1481ed24179 campbellbarton: Update, v1.cross(v2) now works for 2d vectors. https://developer.blender.
(+v1.xv2.x +v1.yv2.y, +v1.yv2.x -v1.xv2.y),		(v1.xv2.x + v1.yv2.y, v1.yv2.x - v1.xv2.y),
(+v1.xv2.y -v1.yv2.x, +v1.xv2.x +v1.yv2.y)))		(v1.xv2.y - v1.yv2.x, v1.xv2.x + v1.yv2.y)))


def z_up_matrix(n):		def z_up_matrix(n):
"""Get a rotation matrix that aligns given vector upwards."""		"""Get a rotation matrix that aligns given vector upwards."""
b=n.xy.length		b = n.xy.length
l=n.length		l = n.length
if b>0:		if b > 0:
return M.Matrix((		return M.Matrix((
(n.xn.z/(bl), n.yn.z/(bl), -b/l),		(n.xn.z/(bl), n.yn.z/(bl), -b/l),
( -n.y/b, n.x/b, 0),		(-n.y/b, n.x/b, 0),
( 0, 0, 0)))		(0, 0, 0)
else: #no need for rotation		))
		else:
		# no need for rotation
return M.Matrix((		return M.Matrix((
(1, 0, 0),		(1, 0, 0),
(0, sign(n.z), 0),		(0, (-1 if n.z < 0 else 1), 0),
(0, 0, 0)))		(0, 0, 0)
		))


def create_blank_image(image_name, dimensions, alpha=1):		def create_blank_image(image_name, dimensions, alpha=1):
"""Create a new image and assign white color to all its pixels"""		"""Create a new image and assign white color to all its pixels"""
image_name = image_name[:20]		image_name = image_name[:64]
image = bpy.data.images.new(image_name, dimensions.x, dimensions.y, alpha=True)		width, height = int(dimensions.x), int(dimensions.y)
		image = bpy.data.images.new(image_name, width, height, alpha=True)
if image.users > 0:		if image.users > 0:
raise UnfoldError("There is something wrong with the material of the model. Please report this on the BlenderArtists forum. Export failed.")		raise UnfoldError("There is something wrong with the material of the model. "
image.pixels = [1,1,1,alpha] * int(dimensions.x*dimensions.y)		"Please report this on the BlenderArtists forum. Export failed.")
		image.pixels = [1, 1, 1, alpha] * (width * height)
image.file_format = 'PNG'		image.file_format = 'PNG'
return image		return image

def create_texface_material(name):
"""Create a new material for baking the Face Texture"""
mat = bpy.data.materials.new(name)
mat.use_shadeless = True
mat.use_face_texture = True
return mat

def tempfile_name(directory, suffix, exists):
"""Generate a nonexistant filename"""
for mod in (10, 100, 1000, 10000):
name = str(id(tempfile_name) % mod + 1) + suffix
if not exists("{}/{}".format(directory, name)):
return name
raise UnfoldError("Could not save a temporary file. Export failed.")

class UnfoldError(ValueError):		class UnfoldError(ValueError):
pass		pass


class Unfolder:		class Unfolder:
def __init__(self, ob):		def __init__(self, ob):
self.ob=ob		self.ob = ob
self.mesh=Mesh(ob.data, ob.matrix_world)		self.mesh = Mesh(ob.data, ob.matrix_world)
self.tex = None		self.tex = None
		campbellbartonUnsubmitted Not Done Inline Actions image names can be up to 64 characters now, does this size need updating? campbellbarton: image names can be up to 64 characters now, does this size need updating?

def prepare(self, page_size=None, create_uvmap=False, mark_seams=False, priority_effect=default_priority_effect, scale=1):		def prepare(self, page_size=None, create_uvmap=False, mark_seams=False, priority_effect=default_priority_effect, scale=1):
"""Create the islands of the net"""		"""Create the islands of the net"""
		page_size = page_size / scale if page_size else None
self.mesh.generate_cuts(page_size, priority_effect)		self.mesh.generate_cuts(page_size, priority_effect)
self.mesh.finalize_islands(scale_factor=scale)		self.mesh.finalize_islands(scale_factor=scale, aspect_ratio=210/297) #TODO wtf? should be based on page_size
self.mesh.enumerate_islands()		self.mesh.enumerate_islands()
if create_uvmap:		if create_uvmap:
self.tex = self.mesh.save_uv()		self.tex = self.mesh.save_uv()
if mark_seams:		if mark_seams:
self.mesh.mark_cuts()		self.mesh.mark_cuts()

def copy_island_names(self, island_list):		def copy_island_names(self, island_list):
"""Copy island label and abbreviation from the best matching island in the list"""		"""Copy island label and abbreviation from the best matching island in the list"""
orig_list = {(frozenset(face.id for face in item.faces), item.label, item.abbreviation) for item in island_list}		orig_list = {(frozenset(face.id for face in item.faces), item.label, item.abbreviation) for item in island_list}
		campbellbartonUnsubmitted Not Done Inline Actions Best use pythons `tempfile` - http://docs.python.org/3/library/tempfile.html campbellbarton: Best use pythons `tempfile` - http://docs.python.org/3/library/tempfile.html
for island in self.mesh.islands:		for island in self.mesh.islands:
islfaces = {uvface.face.index for uvface in island.faces}		islfaces = {uvface.face.index for uvface in island.faces}
match = max(orig_list, key=lambda item: islfaces.intersection(item[0]))		match = max(orig_list, key=lambda item: islfaces.intersection(item[0]))
island.label = match[1]		island.label = match[1]
island.abbreviation = match[2]		island.abbreviation = match[2]

def save(self, properties):		def save(self, properties):
"""Export the document."""		"""Export the document"""
# Note about scale: input is direcly in blender length. finalize_islands multiplies everything by scale/page_size.y, SVG object multiplies everything by page_size.y*ppm.		# Note about scale: input is direcly in blender length.
		# finalize_islands multiplies everything by scale/page_size.y
		# SVG object multiplies everything by page_size.y*ppm.
filepath=properties.filepath		filepath = properties.filepath
if filepath[-4:]==".svg" or filepath[-4:]==".png":		if filepath.lower().endswith((".svg", ".png")):
filepath=filepath[0:-4]		filepath = filepath[0:-4]
page_size = M.Vector((properties.output_size_x, properties.output_size_y)) # page size in meters		# page size in meters
printable_size = page_size - 2 * properties.output_margin * M.Vector((1, 1)) # printable area size in meters		page_size = M.Vector((properties.output_size_x, properties.output_size_y))
		# printable area size in meters
		printable_size = page_size - 2 * properties.output_margin * M.Vector((1, 1))
scale = bpy.context.scene.unit_settings.scale_length / properties.scale		scale = bpy.context.scene.unit_settings.scale_length / properties.scale
ppm = properties.output_dpi * 100 / 2.54 # pixels per meter		ppm = properties.output_dpi * 100 / 2.54 # pixels per meter

if properties.do_create_stickers:		if properties.do_create_stickers:
self.mesh.generate_stickers(properties.sticker_width * printable_size.y / scale, properties.do_create_numbers)		self.mesh.generate_stickers(properties.sticker_width * printable_size.y / scale, properties.do_create_numbers)
elif properties.do_create_numbers:		elif properties.do_create_numbers:
self.mesh.generate_numbers_alone(properties.sticker_width * printable_size.y / scale)		self.mesh.generate_numbers_alone(properties.sticker_width * printable_size.y / scale)

text_height = 12/(printable_size.y*ppm) if (properties.do_create_numbers and len(self.mesh.islands) > 1) else 0		text_height = 12 / (printable_size.y*ppm) if (properties.do_create_numbers and len(self.mesh.islands) > 1) else 0
self.mesh.finalize_islands(scale_factor=scale / printable_size.y, title_height=text_height) # Scale everything so that page height is 1		aspect_ratio = printable_size.x / printable_size.y
self.mesh.fit_islands(aspect_ratio=printable_size.x / printable_size.y)		# finalizing islands will scale everything so that the page height is 1
		self.mesh.finalize_islands(scale_factor=scale/printable_size.y, title_height=text_height, aspect_ratio=aspect_ratio)
		self.mesh.fit_islands(aspect_ratio=aspect_ratio)

if properties.output_type != 'NONE':		if properties.output_type != 'NONE':
# bake an image and save it as a PNG to disk or into memory		# bake an image and save it as a PNG to disk or into memory
use_separate_images = properties.image_packing in ('ISLAND_LINK', 'ISLAND_EMBED')		use_separate_images = properties.image_packing in ('ISLAND_LINK', 'ISLAND_EMBED')
tex = self.mesh.save_uv(aspect_ratio=printable_size.x/printable_size.y, separate_image=use_separate_images, tex=self.tex)		tex = self.mesh.save_uv(aspect_ratio=printable_size.x/printable_size.y, separate_image=use_separate_images, tex=self.tex)
if not tex:		if not tex:
raise UnfoldError("The mesh has no UV Map slots left. Either delete a UV Map or export the net without textures.")		raise UnfoldError("The mesh has no UV Map slots left. Either delete a UV Map or export the net without textures.")
if properties.output_type == 'TEXTURE' and tex.active_render:		if properties.output_type == 'TEXTURE' and tex.active_render:
tex.active = True		tex.active = True
		campbellbartonUnsubmitted Not Done Inline Actions prefer `filepath.lower().endswith((".svg", ".png"))` campbellbarton: prefer `filepath.lower().endswith((".svg", ".png"))`
bpy.ops.mesh.uv_texture_remove()		bpy.ops.mesh.uv_texture_remove()
raise UnfoldError("Texture bake error. Material of the object is referring to an undefined UV Map.")		raise UnfoldError("Texture bake error. Probably a UV Map is missing.")
rd = bpy.context.scene.render		rd = bpy.context.scene.render
recall = rd.bake_type, rd.use_bake_to_vertex_color, rd.use_bake_selected_to_active, rd.bake_distance, rd.bake_bias, rd.bake_margin, rd.use_bake_clear		recall = rd.bake_type, rd.use_bake_to_vertex_color, rd.use_bake_selected_to_active, rd.bake_distance, rd.bake_bias, rd.bake_margin, rd.use_bake_clear

if properties.output_type == 'RENDER':		if properties.output_type == 'RENDER':
rd.bake_type = 'FULL'		rd.bake_type = 'FULL'
rd.use_bake_selected_to_active = False		rd.use_bake_selected_to_active = False

elif properties.output_type == 'TEXTURE':		elif properties.output_type == 'TEXTURE':
rd.bake_type = 'TEXTURE'		rd.bake_type = 'TEXTURE'
rd.use_bake_selected_to_active = False		rd.use_bake_selected_to_active = False
recall_materials = [slot.material for slot in self.ob.material_slots]		recall_materials = [slot.material for slot in self.ob.material_slots]
print(recall_materials)		mat = bpy.data.materials.new("unfolder_temp")
mat = create_texface_material("unfolder_temp")		mat.use_shadeless = True
		mat.use_face_texture = True
for slot in self.ob.material_slots:		for slot in self.ob.material_slots:
slot.material = mat		slot.material = mat
if not recall_materials:		if not recall_materials:
# this is a crazy workaround. I don't get the material system, but I believe nobody does		# this is a crazy hack. Sometimes, slots must be accessed
		# through ob.material_slots, sometimes ob.data.materials
self.ob.data.materials.append(mat)		self.ob.data.materials.append(mat)

elif properties.output_type == 'SELECTED_TO_ACTIVE':		elif properties.output_type == 'SELECTED_TO_ACTIVE':
rd.bake_type = 'FULL'		rd.bake_type = 'FULL'
rd.use_bake_selected_to_active = True		rd.use_bake_selected_to_active = True

rd.bake_margin, rd.bake_distance, rd.bake_bias, rd.use_bake_to_vertex_color, rd.use_bake_clear = 0, 0, 0.001, False, False		rd.bake_margin, rd.bake_distance, rd.bake_bias, rd.use_bake_to_vertex_color, rd.use_bake_clear = 0, 0, 0.001, False, False
if properties.image_packing == 'PAGE_LINK':		if properties.image_packing == 'PAGE_LINK':
self.mesh.save_image(tex, printable_size * ppm, filepath)		self.mesh.save_image(tex, printable_size * ppm, filepath)
elif properties.image_packing == 'ISLAND_LINK':		elif properties.image_packing == 'ISLAND_LINK':
self.mesh.save_separate_images(tex, printable_size.y * ppm, filepath)		self.mesh.save_separate_images(tex, printable_size.y * ppm, filepath)
elif properties.image_packing == 'ISLAND_EMBED':		elif properties.image_packing == 'ISLAND_EMBED':
self.mesh.save_separate_images(tex, printable_size.y * ppm, filepath, do_embed=True)		self.mesh.save_separate_images(tex, printable_size.y * ppm, filepath, do_embed=True)

#revoke settings		# revoke settings
rd.bake_type, rd.use_bake_to_vertex_color, rd.use_bake_selected_to_active, rd.bake_distance, rd.bake_bias, rd.bake_margin, rd.use_bake_clear = recall		rd.bake_type, rd.use_bake_to_vertex_color, rd.use_bake_selected_to_active, rd.bake_distance, rd.bake_bias, rd.bake_margin, rd.use_bake_clear = recall
if properties.output_type == 'TEXTURE':		if properties.output_type == 'TEXTURE':
for slot, material in zip(self.ob.material_slots, recall_materials):		for slot, material in zip(self.ob.material_slots, recall_materials):
slot.material = material		slot.material = material
if not recall_materials:		if not recall_materials:
# another crazy workaround, remove the material slot we have created		# another crazy workaround, remove the material slot we have created
self.ob.data.materials.pop()		self.ob.data.materials.pop()
mat.user_clear()		mat.user_clear()
bpy.data.materials.remove(mat)		bpy.data.materials.remove(mat)
if not properties.do_create_uvmap:		if not properties.do_create_uvmap:
tex.active = True		tex.active = True
bpy.ops.mesh.uv_texture_remove()		bpy.ops.mesh.uv_texture_remove()

svg = SVG(page_size * ppm, printable_size.y * ppm, properties.style, (properties.output_type == 'NONE'))		svg = SVG(page_size * ppm, printable_size.y * ppm, properties.style, (properties.output_type == 'NONE'))
svg.do_create_stickers = properties.do_create_stickers		svg.do_create_stickers = properties.do_create_stickers
svg.margin = properties.output_margin * ppm		svg.margin = properties.output_margin * ppm
svg.write(self.mesh, filepath)		svg.write(self.mesh, filepath)


class Mesh:		class Mesh:
"""Wrapper for Bpy Mesh"""		"""Wrapper for Bpy Mesh"""

def __init__(self, mesh, matrix):		def __init__(self, mesh, matrix):
self.verts=dict()		self.verts = dict()
self.edges=dict()		self.edges = dict()
self.edges_by_verts_indices=dict()		self.edges_by_verts_indices = dict()
self.faces=dict()		self.faces = dict()
self.islands=list()		self.islands = list()
self.data=mesh		self.data = mesh
self.pages=list()		self.pages = list()
for bpy_vertex in mesh.vertices:		for bpy_vertex in mesh.vertices:
self.verts[bpy_vertex.index]=Vertex(bpy_vertex, self, matrix)		self.verts[bpy_vertex.index] = Vertex(bpy_vertex, self, matrix)
for bpy_edge in mesh.edges:		for bpy_edge in mesh.edges:
edge=Edge(bpy_edge, self, matrix)		edge = Edge(bpy_edge, self, matrix)
self.edges[bpy_edge.index] = edge		self.edges[bpy_edge.index] = edge
self.edges_by_verts_indices[(edge.va.index, edge.vb.index)] = edge		self.edges_by_verts_indices[(edge.va.index, edge.vb.index)] = edge
self.edges_by_verts_indices[(edge.vb.index, edge.va.index)] = edge		self.edges_by_verts_indices[(edge.vb.index, edge.va.index)] = edge
for bpy_face in mesh.polygons:		for bpy_face in mesh.polygons:
face = Face(bpy_face, self)		face = Face(bpy_face, self)
self.faces[bpy_face.index] = face		self.faces[bpy_face.index] = face
for index in self.edges:		for index in self.edges:
edge = self.edges[index]		edge = self.edges[index]
edge.choose_main_faces()		edge.choose_main_faces()
if edge.main_faces:		if edge.main_faces:
edge.calculate_angle()		edge.calculate_angle()

def generate_cuts(self, page_size, priority_effect):		def generate_cuts(self, page_size, priority_effect):
"""Cut the mesh so that it will be unfoldable."""		"""Cut the mesh so that it can be unfolded to a flat net."""

twisted_faces = [face for face in self.faces.values() if face.is_twisted()]
if twisted_faces:
print ("There are {} twisted face(s) with ids: {}".format(len(twisted_faces), ", ".join(str(face.index) for face in twisted_faces)))

# warning: this constructor modifies its parameter (face)		# warning: this constructor modifies its parameter (face)
islands = {Island(face) for face in self.faces.values()}		islands = {Island(face) for face in self.faces.values()}
# check for edges that are cut permanently		# check for edges that are cut permanently
edges = [edge for edge in self.edges.values() if not edge.force_cut and len(edge.faces) > 1]		edges = [edge for edge in self.edges.values() if not edge.force_cut and len(edge.faces) > 1]

if edges:		if edges:
average_length = sum(edge.length for edge in edges) / len(edges)		average_length = sum(edge.length for edge in edges) / len(edges)
for edge in edges:		for edge in edges:
edge.generate_priority(priority_effect, average_length)		edge.generate_priority(priority_effect, average_length)
edges.sort(key = lambda edge:edge.priority, reverse=False)		edges.sort(reverse=False, key=lambda edge: edge.priority)
for edge in edges:		for edge in edges:
if edge.length == 0:		if edge.length == 0:
continue		continue
face_a, face_b = edge.main_faces		face_a, face_b = edge.main_faces
island_a, island_b = face_a.uvface.island, face_b.uvface.island		island_a, island_b = face_a.uvface.island, face_b.uvface.island
		if island_a is not island_b:
if len(island_b.faces) > len(island_a.faces):		if len(island_b.faces) > len(island_a.faces):
island_a, island_b = island_b, island_a		island_a, island_b = island_b, island_a
if island_a is not island_b:
if island_a.join(island_b, edge, size_limit=page_size):		if island_a.join(island_b, edge, size_limit=page_size):
islands.remove(island_b)		islands.remove(island_b)

self.islands = sorted(islands, key=lambda island: len(island.faces), reverse=True)		self.islands = sorted(islands, reverse=True, key=lambda island: len(island.faces))

for edge in self.edges.values():		for edge in self.edges.values():
# some edges did not know until now whether their angle is convex or concave		# some edges did not know until now whether their angle is convex or concave
if edge.main_faces and (edge.main_faces[0].uvface.flipped or edge.main_faces[1].uvface.flipped):		if edge.main_faces and (edge.main_faces[0].uvface.flipped or edge.main_faces[1].uvface.flipped):
edge.calculate_angle()		edge.calculate_angle()
# ensure that the order of faces corresponds to the order of uvedges		# ensure that the order of faces corresponds to the order of uvedges
if len(edge.uvedges) >= 2:		if len(edge.uvedges) >= 2:
reordered = [None, None]		reordered = [None, None]
for uvedge in edge.uvedges:		for uvedge in edge.uvedges:
try:		try:
index = edge.main_faces.index(uvedge.uvface.face)		index = edge.main_faces.index(uvedge.uvface.face)
reordered[index] = uvedge		reordered[index] = uvedge
except ValueError:		except ValueError:
reordered.append(uvedge)		reordered.append(uvedge)
edge.uvedges = reordered		edge.uvedges = reordered

for island in self.islands:		for island in self.islands:
# flip normals so that there are more convex edges than concave ones		# if the normals are ambiguous, flip them so that there are more convex edges than concave ones
if any(uvface.flipped for uvface in island.faces): # do nothing to islands that have correct normals		if any(uvface.flipped for uvface in island.faces):
island_edges = {uvedge.edge for uvedge in island.edges if not uvedge.edge.is_cut(uvedge.uvface.face)}		island_edges = {uvedge.edge for uvedge in island.edges if not uvedge.edge.is_cut(uvedge.uvface.face)}
balance = sum((+1 if edge.angle > 0 else -1) for edge in island_edges)		balance = sum((+1 if edge.angle > 0 else -1) for edge in island_edges)
if balance < 0:		if balance < 0:
island.is_inside_out = True		island.is_inside_out = True

# construct a linked list from each island's boundary		# construct a linked list from each island's boundary
# uvedge.neighbor_right is clockwise = forward = via uvedge.vb if not uvface.flipped		# uvedge.neighbor_right is clockwise = forward = via uvedge.vb if not uvface.flipped
neighbor_lookup, conflicts = dict(), dict()		neighbor_lookup, conflicts = dict(), dict()
for uvedge in island.boundary_sorted:		for uvedge in island.boundary:
uvvertex = uvedge.va if uvedge.uvface.flipped else uvedge.vb		uvvertex = uvedge.va if uvedge.uvface.flipped else uvedge.vb
if uvvertex not in neighbor_lookup:		if uvvertex not in neighbor_lookup:
neighbor_lookup[uvvertex] = uvedge		neighbor_lookup[uvvertex] = uvedge
else:		else:
if uvvertex not in conflicts:		if uvvertex not in conflicts:
conflicts[uvvertex] = [neighbor_lookup[uvvertex], uvedge]		conflicts[uvvertex] = [neighbor_lookup[uvvertex], uvedge]
else:		else:
conflicts[uvvertex].append(uvedge)		conflicts[uvvertex].append(uvedge)

for uvedge in island.boundary_sorted:		for uvedge in island.boundary:
uvvertex = uvedge.vb if uvedge.uvface.flipped else uvedge.va		uvvertex = uvedge.vb if uvedge.uvface.flipped else uvedge.va
if uvvertex not in conflicts:		if uvvertex not in conflicts:
uvedge.neighbor_right = neighbor_lookup[uvvertex]		# using the 'get' method so as to handle single-connected vertices properly
		uvedge.neighbor_right = neighbor_lookup.get(uvvertex, uvedge)
uvedge.neighbor_right.neighbor_left = uvedge		uvedge.neighbor_right.neighbor_left = uvedge
else:		else:
conflicts[uvvertex].append(uvedge)		conflicts[uvvertex].append(uvedge)

# solve merged vertices with more boundaries crossing		# resolve merged vertices with more boundaries crossing
direction_to_float = lambda vector: (1 - vector.x/vector.length) if vector.y > 0 else (vector.x/vector.length - 1)		def direction_to_float(vector):
		return (1 - vector.x/vector.length) if vector.y > 0 else (vector.x/vector.length - 1)
for uvvertex, uvedges in conflicts.items():		for uvvertex, uvedges in conflicts.items():
is_inwards = lambda uvedge: uvedge.uvface.flipped == (uvedge.va is uvvertex)		def is_inwards(uvedge):
uvedge_sortkey = lambda uvedge: direction_to_float((uvedge.va.co-uvedge.vb.co) if is_inwards(uvedge) else (uvedge.vb.co-uvedge.va.co))		return uvedge.uvface.flipped == (uvedge.va is uvvertex)

		def uvedge_sortkey(uvedge):
		if is_inwards(uvedge):
		return direction_to_float(uvedge.va.co - uvedge.vb.co)
		else:
		return direction_to_float(uvedge.vb.co - uvedge.va.co)

uvedges.sort(key=uvedge_sortkey)		uvedges.sort(key=uvedge_sortkey)
for right, left in zip(uvedges[:-1:2], uvedges[1::2]) if is_inwards(uvedges[0]) else zip([uvedges[-1]]+uvedges[1::2], uvedges[:-1:2]):		for right, left in zip(uvedges[:-1:2], uvedges[1::2]) if is_inwards(uvedges[0]) else zip([uvedges[-1]] + uvedges[1::2], uvedges[:-1:2]):
left.neighbor_right = right		left.neighbor_right = right
right.neighbor_left = left		right.neighbor_left = left
return True		return True

def mark_cuts(self):		def mark_cuts(self):
"""Mark cut edges in the original mesh so that the user can see"""		"""Mark cut edges in the original mesh so that the user can see"""
for edge in self.edges.values():		for bpy_edge in self.data.edges:
edge.data.use_seam = len(edge.uvedges) > 1 and edge.is_main_cut		edge = self.edges[bpy_edge.index]
		bpy_edge.use_seam = len(edge.uvedges) > 1 and edge.is_main_cut

def generate_stickers(self, default_width, do_create_numbers=True):		def generate_stickers(self, default_width, do_create_numbers=True):
"""Add sticker faces where they are needed."""		"""Add sticker faces where they are needed."""
def uvedge_priority(uvedge):		def uvedge_priority(uvedge):
"""Retuns whether it is a good idea to stick something on this edge's face"""		"""Retuns whether it is a good idea to stick something on this edge's face"""
#TODO: it should take into account overlaps with faces and with other stickers		# TODO: it should take into account overlaps with faces and with other stickers
return uvedge.uvface.face.area / sum((vb.co-va.co).length for (va, vb) in pairs(uvedge.uvface.verts))		return uvedge.uvface.face.area / sum((vb.co - va.co).length for (va, vb) in pairs(uvedge.uvface.verts))

		def add_sticker(uvedge, index, target_island):
		uvedge.sticker = Sticker(uvedge, default_width, index, target_island)
		uvedge.island.add_marker(uvedge.sticker)

for edge in self.edges.values():		for edge in self.edges.values():
if edge.is_main_cut and len(edge.uvedges) >= 2:		if edge.is_main_cut and len(edge.uvedges) >= 2:
uvedge_a, uvedge_b = edge.uvedges[:2]		uvedge_a, uvedge_b = edge.uvedges[:2]
if uvedge_priority(uvedge_a) < uvedge_priority(uvedge_b):		if uvedge_priority(uvedge_a) < uvedge_priority(uvedge_b):
uvedge_a, uvedge_b = uvedge_b, uvedge_a		uvedge_a, uvedge_b = uvedge_b, uvedge_a
target_island = uvedge_a.island		target_island = uvedge_a.island
left_edge, right_edge = uvedge_a.neighbor_left.edge, uvedge_a.neighbor_right.edge		left_edge, right_edge = uvedge_a.neighbor_left.edge, uvedge_a.neighbor_right.edge
if do_create_numbers:		if do_create_numbers:
for uvedge in [uvedge_b] + edge.uvedges[2:]:		for uvedge in [uvedge_b] + edge.uvedges[2:]:
if (uvedge.neighbor_left.edge is not right_edge or uvedge.neighbor_right.edge is not left_edge) and\		if ((uvedge.neighbor_left.edge is not right_edge or uvedge.neighbor_right.edge is not left_edge) and
uvedge not in (uvedge_a.neighbor_left, uvedge_a.neighbor_right):		uvedge not in (uvedge_a.neighbor_left, uvedge_a.neighbor_right)):
# it is perhaps not easy to see that these uvedges should be sticked together. So, create an arrow and put the index on all stickers		# it will not be clear to see that these uvedges should be sticked together
		# So, create an arrow and put the index on all stickers
target_island.sticker_numbering += 1		target_island.sticker_numbering += 1
index = str(target_island.sticker_numbering)		index = str(target_island.sticker_numbering)
		# if the index would have a different meaning upside down, append a dot
if {'6','9'} < set(index) < {'6','8','9','0'}:		if {'6', '9'} < set(index) < {'6', '8', '9', '0'}:
# if index consists of the digits 6, 8, 9, 0 only and contains 6 or 9, make it distinguishable
index += "."		index += "."
target_island.add_marker(Arrow(uvedge_a, default_width, index))		target_island.add_marker(Arrow(uvedge_a, default_width, index))
break		break
else:		else:
# if all uvedges to be sticked are easy to see, create no numbers		# if all uvedges to be sticked are easy to see, create no numbers
index = None		index = None
else:		else:
index = None		index = None
uvedge_b.island.add_marker(Sticker(uvedge_b, default_width, index, target_island))		add_sticker(uvedge_b, index, target_island)
elif len(edge.uvedges) > 2:		elif len(edge.uvedges) > 2:
index = None		index = None
target_island = edge.uvedges[0].island		target_island = edge.uvedges[0].island
if len(edge.uvedges) > 2:		if len(edge.uvedges) > 2:
for uvedge in edge.uvedges[2:]:		for uvedge in edge.uvedges[2:]:
uvedge.island.add_marker(Sticker(uvedge, default_width, index, target_island))		add_sticker(uvedge, index, target_island)

def generate_numbers_alone(self, size):		def generate_numbers_alone(self, size):
global_numbering = 0		global_numbering = 0
for edge in self.edges.values():		for edge in self.edges.values():
if edge.is_main_cut and len(edge.uvedges) >= 2:		if edge.is_main_cut and len(edge.uvedges) >= 2:
global_numbering += 1		global_numbering += 1
index = str(global_numbering)		index = str(global_numbering)
if ('6' in index or '9' in index) and set(index) <= {'6','8','9','0'}:		if ('6' in index or '9' in index) and set(index) <= {'6', '8', '9', '0'}:
# if index consists of the digits 6, 8, 9, 0 only and contains 6 or 9, make it distinguishable		# if index consists of the digits 6, 8, 9, 0 only and contains 6 or 9, make it distinguishable
index += "."		index += "."
for uvedge in edge.uvedges:		for uvedge in edge.uvedges:
uvedge.island.add_marker(NumberAlone(uvedge, index, size))		uvedge.island.add_marker(NumberAlone(uvedge, index, size))

def enumerate_islands(self):		def enumerate_islands(self):
for num, island in enumerate(self.islands, 1):		for num, island in enumerate(self.islands, 1):
island.number = num		island.number = num
island.generate_label()		island.generate_label()

def finalize_islands(self, scale_factor=1, title_height=0):		def finalize_islands(self, scale_factor=1, title_height=0, aspect_ratio=1):
for island in self.islands:		for island in self.islands:
island.apply_scale(scale_factor)		island.apply_scale(scale_factor)
if title_height:		if title_height:
island.title = "[{}] {}".format(island.abbreviation, island.label)		island.title = "[{}] {}".format(island.abbreviation, island.label)
island.generate_bounding_box(space_at_bottom = title_height)		island.generate_bounding_box(space_at_bottom=title_height, aspect_ratio=aspect_ratio)

def largest_island_ratio(self, page_size):		def largest_island_ratio(self, page_size):
largest_ratio=0		return max(max(island.bounding_box.x / page_size.x, island.bounding_box.y / page_size.y) for island in self.islands)
for island in self.islands:
ratio=max(island.bounding_box.x/page_size.x, island.bounding_box.y/page_size.y)
largest_ratio=max(ratio, largest_ratio)
return largest_ratio

def fit_islands(self, aspect_ratio):		def fit_islands(self, aspect_ratio):
"""Move islands so that they fit onto pages, based on their bounding boxes"""		"""Move islands so that they fit onto pages, based on their bounding boxes"""

def try_emplace(island, page_islands, page_size, stops_x, stops_y, occupied_cache):		def try_emplace(island, page_islands, page_size, stops_x, stops_y, occupied_cache):
"""Tries to put island to each pair from stops_x, stops_y		"""Tries to put island to each pair from stops_x, stops_y
and checks if it overlaps with any islands present on the page.		and checks if it overlaps with any islands present on the page.
Returns True and positions the given island on success."""		Returns True and positions the given island on success."""
bbox_x, bbox_y = island.bounding_box.xy		bbox_x, bbox_y = island.bounding_box.xy
for x in stops_x:		for x in stops_x:
if x + bbox_x > page_size.x:		if x + bbox_x > page_size.x:
continue		continue
for y in stops_y:		for y in stops_y:
if y + bbox_y > page_size.y or (x, y) in occupied_cache:		if y + bbox_y > page_size.y or (x, y) in occupied_cache:
continue		continue
for i, obstacle in enumerate(page_islands):		for i, obstacle in enumerate(page_islands):
# if this obstacle overlaps with the island, try another stop		# if this obstacle overlaps with the island, try another stop
if x + bbox_x > obstacle.pos.x and \		if (x + bbox_x > obstacle.pos.x and
obstacle.pos.x + obstacle.bounding_box.x > x and \		obstacle.pos.x + obstacle.bounding_box.x > x and
y + bbox_y > obstacle.pos.y and \		y + bbox_y > obstacle.pos.y and
obstacle.pos.y + obstacle.bounding_box.y > y:		obstacle.pos.y + obstacle.bounding_box.y > y):
if x >= obstacle.pos.x and y >= obstacle.pos.y:		if x >= obstacle.pos.x and y >= obstacle.pos.y:
occupied_cache.add((x, y))		occupied_cache.add((x, y))
# just a stupid heuristic to make subsequent searches faster		# just a stupid heuristic to make subsequent searches faster
if i > 0:		if i > 0:
page_islands[1:i+1] = page_islands[:i]		page_islands[1:i+1] = page_islands[:i]
page_islands[0] = obstacle		page_islands[0] = obstacle
break		break
else:		else:
Show All 9 Lines	def drop_portion(stops, border, divisor):
stops.sort()		stops.sort()
# distance from left neighbor to the right one, excluding the first stop		# distance from left neighbor to the right one, excluding the first stop
distances = [right - left for left, right in zip(stops, chain(stops[2:], [border]))]		distances = [right - left for left, right in zip(stops, chain(stops[2:], [border]))]
quantile = sorted(distances)[len(distances) // divisor]		quantile = sorted(distances)[len(distances) // divisor]
return [stop for stop, distance in zip(stops, chain([quantile], distances)) if distance >= quantile]		return [stop for stop, distance in zip(stops, chain([quantile], distances)) if distance >= quantile]

page_size = M.Vector((aspect_ratio, 1))		page_size = M.Vector((aspect_ratio, 1))
if any(island.bounding_box.x > page_size.x or island.bounding_box.y > page_size.y for island in self.islands):		if any(island.bounding_box.x > page_size.x or island.bounding_box.y > page_size.y for island in self.islands):
raise UnfoldError("An island is too big to fit onto page of the given size. Either downscale the model or find and split that island manually.\nExport failed, sorry.")		raise UnfoldError("An island is too big to fit onto page of the given size. "
		"Either downscale the model or find and split that island manually.\n"
		"Export failed, sorry.")
# sort islands by their diagonal... just a guess		# sort islands by their diagonal... just a guess
remaining_islands = sorted(self.islands, reverse=True, key=lambda island: island.bounding_box.length_squared)		remaining_islands = sorted(self.islands, reverse=True, key=lambda island: island.bounding_box.length_squared)
page_num = 1		page_num = 1

while remaining_islands:		while remaining_islands:
# create a new page and try to fit as many islands onto it as possible		# create a new page and try to fit as many islands onto it as possible
page = Page(page_num)		page = Page(page_num)
page_num += 1		page_num += 1
occupied_cache = set()		occupied_cache = set()
stops_x, stops_y = [0], [0]		stops_x, stops_y = [0], [0]
for island in remaining_islands:		for island in remaining_islands:
try_emplace(island, page.islands, page_size, stops_x, stops_y, occupied_cache)		try_emplace(island, page.islands, page_size, stops_x, stops_y, occupied_cache)
# if overwhelmed with stops, drop a quarter of them		# if overwhelmed with stops, drop a quarter of them
if len(stops_x)*2 > 4 len(self.islands) + 100:		if len(stops_x)*2 > 4 len(self.islands) + 100:
stops_x = drop_portion(stops_x, page_size.x, 4)		stops_x = drop_portion(stops_x, page_size.x, 4)
stops_y = drop_portion(stops_y, page_size.y, 4)		stops_y = drop_portion(stops_y, page_size.y, 4)
remaining_islands = [island for island in remaining_islands if island not in page.islands]		remaining_islands = [island for island in remaining_islands if island not in page.islands]
self.pages.append(page)		self.pages.append(page)

def save_uv(self, aspect_ratio=1, separate_image=False, tex=None): #page_size is in pixels		def save_uv(self, aspect_ratio=1, separate_image=False, tex=None):
		# TODO: mode switching should be handled by higher-level code
bpy.ops.object.mode_set()		bpy.ops.object.mode_set()
#note: expecting that the active object's data is self.mesh		# note: assuming that the active object's data is self.mesh
if not tex:		if not tex:
tex = self.data.uv_textures.new()		tex = self.data.uv_textures.new()
if not tex:		if not tex:
return None		return None
tex.name = "Unfolded"		tex.name = "Unfolded"
tex.active = True		tex.active = True
loop = self.data.uv_layers[self.data.uv_layers.active_index] # TODO: this is somehow dirty, but I don't see a nicer way in the API		# TODO: this is somewhat dirty, but I do not see a nicer way in the API
		loop = self.data.uv_layers[self.data.uv_layers.active_index]
if separate_image:		if separate_image:
for island in self.islands:		for island in self.islands:
island.save_uv_separate(loop)		island.save_uv_separate(loop)
else:		else:
for island in self.islands:		for island in self.islands:
island.save_uv(loop, aspect_ratio)		island.save_uv(loop, aspect_ratio)
return tex		return tex

def save_image(self, tex, page_size_pixels:M.Vector, filename):		def save_image(self, tex, page_size_pixels: M.Vector, filename):
texfaces = tex.data		texfaces = tex.data
# omitting this causes a "Circular reference in texture stack" error		# omitting this causes a "Circular reference in texture stack" error
for island in self.islands:		for island in self.islands:
for uvface in island.faces:		for uvface in island.faces:
texfaces[uvface.face.index].image = None		texfaces[uvface.face.index].image = None

for page in self.pages:		for page in self.pages:
image = create_blank_image("{} {} Unfolded".format(self.data.name[:14], page.name), page_size_pixels, alpha=1)		image = create_blank_image("{} {} Unfolded".format(self.data.name[:14], page.name), page_size_pixels, alpha=1)
image.filepath_raw = page.image_path = "{}_{}.png".format(filename, page.name)		image.filepath_raw = page.image_path = "{}_{}.png".format(filename, page.name)
for island in page.islands:		for island in page.islands:
for uvface in island.faces:		for uvface in island.faces:
texfaces[uvface.face.index].image=image		texfaces[uvface.face.index].image = image
try:		try:
bpy.ops.object.bake_image()		bpy.ops.object.bake_image()
image.save()		image.save()
finally:		finally:
for island in page.islands:		for island in page.islands:
for uvface in island.faces:		for uvface in island.faces:
texfaces[uvface.face.index].image=None		texfaces[uvface.face.index].image = None
image.user_clear()		image.user_clear()
bpy.data.images.remove(image)		bpy.data.images.remove(image)

def save_separate_images(self, tex, scale, filepath, do_embed=False):		def save_separate_images(self, tex, scale, filepath, do_embed=False):
		assert(os_path) # check the module was imported
if do_embed:		if do_embed:
try:		import tempfile
from base64 import encodebytes as b64encode		import base64
from os import remove
from os.path import dirname, lexists
except ImportError:
raise UnfoldError("Embedding images is not supported on your system")
image_dir = dirname(filepath)
else:		else:
try:
from os import mkdir		from os import mkdir
from os.path import dirname, basename		image_dir = filepath
image_dir = "{path}/{directory}".format(path=dirname(filepath), directory=basename(filepath))		try:
mkdir(image_dir)		mkdir(image_dir)
except ImportError:
raise UnfoldError("This method of image packing is not supported by your system.")
except OSError:		except OSError:
pass #image_dir already existed		# image_dir already existed
		pass

texfaces = tex.data		texfaces = tex.data
# omitting this causes a "Circular reference in texture stack" error		# omitting these 3 lines causes a "Circular reference in texture stack" error
for island in self.islands:		for island in self.islands:
for uvface in island.faces:		for uvface in island.faces:
texfaces[uvface.face.index].image = None		texfaces[uvface.face.index].image = None

for i, island in enumerate(self.islands, 1):		for i, island in enumerate(self.islands, 1):
image_name = tempfile_name(image_dir, ".temp.png", lexists) if do_embed else "{} isl{}".format(self.data.name[:15], i)		if do_embed:
		tempfile_manager = tempfile.NamedTemporaryFile("rb", suffix=".png")
		image_path = tempfile_manager.name
		image_name = os_path.basename(tempfile_manager.name)
		# note: image_path exists by now and Blender will overwrite it;
		# we will read later from the same file
		else:
		image_path = os_path.join(image_dir, "island{}.png".format(i))
		image_name = "{} isl{}".format(self.data.name[:15], i)
image = create_blank_image(image_name, island.bounding_box * scale, alpha=0)		image = create_blank_image(image_name, island.bounding_box * scale, alpha=0)
image.filepath_raw = image_path = "{}/{}".format(image_dir, image_name) if do_embed else "{}/island{}.png".format(image_dir, i)		image.filepath_raw = image_path
for uvface in island.faces:		for uvface in island.faces:
texfaces[uvface.face.index].image=image		texfaces[uvface.face.index].image = image

try:		try:
bpy.ops.object.bake_image()		bpy.ops.object.bake_image()
image.save()		image.save()
finally:		finally:
for uvface in island.faces:		for uvface in island.faces:
texfaces[uvface.face.index].image = None		texfaces[uvface.face.index].image = None
image.user_clear()		image.user_clear()
bpy.data.images.remove(image)		bpy.data.images.remove(image)

if do_embed:		if do_embed:
with open(image_path, 'rb') as imgf:		with tempfile_manager as imgfile:
island.embedded_image = b64encode(imgf.read()).decode('ascii')		island.embedded_image = base64.encodebytes(imgfile.read()).decode('ascii')
remove(image_path)
else:		else:
island.image_path = image_path		island.image_path = image_path


class Vertex:		class Vertex:
"""BPy Vertex wrapper"""		"""BPy Vertex wrapper"""
		__slots__ = ('index', 'co', 'edges', 'uvs')

def __init__(self, bpy_vertex, mesh=None, matrix=1):		def __init__(self, bpy_vertex, mesh=None, matrix=1):
self.data=bpy_vertex
self.index=bpy_vertex.index		self.index = bpy_vertex.index
self.co=bpy_vertex.co*matrix		self.co = matrix * bpy_vertex.co
self.edges=list()		self.edges = list()
self.uvs=list()		self.uvs = list()

def __hash__(self):		def __hash__(self):
return hash(self.index)		return hash(self.index)

def __eq__(self, other):		def __eq__(self, other):
if type(other) is type(self):
return self.index==other.index		return self.index == other.index
else:
return False
def __sub__(self, other):
return self.co-other.co
def __rsub__(self, other):
if type(other) is type(self):
return other.co-self.co
else:
return other-self.co
def __add__(self, other):
return self.co+other.co

class Edge:		class Edge:
"""Wrapper for BPy Edge"""		"""Wrapper for BPy Edge"""
		__slots__ = ('va', 'vb', 'faces', 'main_faces', 'uvedges',
		'vect', 'length', 'angle',
		'is_main_cut', 'force_cut', 'priority')

def __init__(self, edge, mesh, matrix=1):		def __init__(self, edge, mesh, matrix=1):
self.data=edge
self.va=mesh.verts[edge.vertices[0]]		self.va = mesh.verts[edge.vertices[0]]
self.vb=mesh.verts[edge.vertices[1]]		self.vb = mesh.verts[edge.vertices[1]]
self.vect=self.vb.co-self.va.co		self.vect = self.vb.co - self.va.co
self.length=self.vect.length		self.length = self.vect.length
self.faces=list()		self.faces = list()
self.uvedges=list() # important: if self.main_faces is set, then self.uvedges[:2] must be the ones corresponding to self.main_faces.		# if self.main_faces is set, then self.uvedges[:2] must be the same to faces as self.main_faces
# It is assured at the time of finishing mesh.generate_cuts		# this constraint is assured at the time of finishing mesh.generate_cuts
		self.uvedges = list()

self.force_cut = bool(edge.use_seam) # such edges will always be cut		self.force_cut = bool(edge.use_seam) # such edges will always be cut
self.main_faces = None # two faces that can be connected in the island		self.main_faces = None # two faces that may be connected in the island
self.is_main_cut = True # defines whether the two main faces are connected; all the others will be automatically treated as cut		# is_main_cut defines whether the two main faces are connected
		# all the others will be assumed to be cut
		self.is_main_cut = True
self.priority=None		self.priority = None
self.angle = None		self.angle = None
self.va.edges.append(self)		self.va.edges.append(self)
self.vb.edges.append(self)		self.vb.edges.append(self)

def choose_main_faces(self):		def choose_main_faces(self):
"""Choose two main faces that might get connected in an island"""		"""Choose two main faces that might get connected in an island"""
if len(self.faces) == 2:		if len(self.faces) == 2:
self.main_faces = self.faces		self.main_faces = self.faces
elif len(self.faces) > 2:		elif len(self.faces) > 2:
# find (with brute force) the pair of indices whose faces have the most similar normals		# find (with brute force) the pair of indices whose faces have the most similar normals
i, j = argmax_pair(self.faces, key=lambda a, b: a.normal.dot(b.normal))		i, j = argmax_pair(self.faces, key=lambda a, b: abs(a.normal.dot(b.normal)))
self.main_faces = self.faces[i], self.faces[j]		self.main_faces = [self.faces[i], self.faces[j]]

def calculate_angle(self):		def calculate_angle(self):
"""Calculate the angle between the main faces"""		"""Calculate the angle between the main faces"""
face_a, face_b = self.main_faces		face_a, face_b = self.main_faces
		if face_a.normal.length_squared == 0 or face_b.normal.length_squared == 0:
		self.angle = -3 # just a very sharp angle
		return
# correction if normals are flipped		# correction if normals are flipped
a_is_clockwise = ((face_a.verts.index(self.va) - face_a.verts.index(self.vb)) % len(face_a.verts) == 1)		a_is_clockwise = ((face_a.verts.index(self.va) - face_a.verts.index(self.vb)) % len(face_a.verts) == 1)
b_is_clockwise = ((face_b.verts.index(self.va) - face_b.verts.index(self.vb)) % len(face_b.verts) == 1)		b_is_clockwise = ((face_b.verts.index(self.va) - face_b.verts.index(self.vb)) % len(face_b.verts) == 1)
afl_eq_bfl = True		is_equal_flip = True
if face_a.uvface and face_b.uvface:		if face_a.uvface and face_b.uvface:
a_is_clockwise ^= face_a.uvface.flipped		a_is_clockwise ^= face_a.uvface.flipped
b_is_clockwise ^= face_b.uvface.flipped		b_is_clockwise ^= face_b.uvface.flipped
afl_eq_bfl = (face_a.uvface.flipped == face_b.uvface.flipped)		is_equal_flip = (face_a.uvface.flipped == face_b.uvface.flipped)
assert(a_is_clockwise != b_is_clockwise)		# TODO: maybe this need not be true in _really_ ugly cases: assert(a_is_clockwise != b_is_clockwise)
if a_is_clockwise != b_is_clockwise:		if a_is_clockwise != b_is_clockwise:
if (a_is_clockwise == (face_b.normal.cross(face_a.normal).dot(self.vect) > 0)) == afl_eq_bfl:		if (a_is_clockwise == (face_b.normal.cross(face_a.normal).dot(self.vect) > 0)) == is_equal_flip:
self.angle = face_a.normal.angle(face_b.normal) # the angle is convex		# the angle is convex
else:		self.angle = face_a.normal.angle(face_b.normal)
self.angle = -face_a.normal.angle(face_b.normal) # the angle is concave		else:
else:		# the angle is concave
self.angle = face_a.normal.angle(-face_b.normal) # normals are flipped, so we know nothing		self.angle = -face_a.normal.angle(face_b.normal)
# but let us be optimistic and treat the angle as convex :)		else:
		# normals are flipped, so we know nothing
		# so let us assume the angle be convex
		self.angle = face_a.normal.angle(-face_b.normal)

def generate_priority(self, priority_effect, average_length):		def generate_priority(self, priority_effect, average_length):
"""Calculate initial priority value."""		"""Calculate the priority value for cutting"""
angle = self.angle		angle = self.angle
if angle > 0:		if angle > 0:
self.priority = (angle/pi) * priority_effect['CONVEX']		self.priority = priority_effect['CONVEX'] * angle / pi
else:		else:
self.priority = -(angle/pi) * priority_effect['CONCAVE']		self.priority = priority_effect['CONCAVE'] * (-angle) / pi
self.priority += (self.length/average_length) * priority_effect['LENGTH']		self.priority += (self.length / average_length) * priority_effect['LENGTH']

def is_cut(self, face=None):		def is_cut(self, face):
"""Optional argument 'face' defines who is asking (useful for edges with more than two faces connected)"""		"""Return False if this edge will the given face to another one in the resulting net
		(useful for edges with more than two faces connected)"""
#Return whether there is a cut between the two main faces		# Return whether there is a cut between the two main faces
if face is None or (self.main_faces and face in self.main_faces):		if self.main_faces and face in self.main_faces:
return self.is_main_cut		return self.is_main_cut
#All other faces (third and more) are automatically treated as cut		# All other faces (third and more) are automatically treated as cut
else:		else:
return True		return True

def other_uvedge(self, this):		def other_uvedge(self, this):
"""Get an uvedge of this edge that is not the given one - or None if no other uvedge was found."""		"""Get an uvedge of this edge that is not the given one
if len(self.uvedges) < 2:		causes an IndexError if case of less than two adjacent edges"""
return None
return self.uvedges[1] if this is self.uvedges[0] else self.uvedges[0]		return self.uvedges[1] if this is self.uvedges[0] else self.uvedges[0]


class Face:		class Face:
"""Wrapper for BPy Face"""		"""Wrapper for BPy Face"""
		__slots__ = ('index', 'edges', 'verts', 'uvface',
		'loop_start', 'area', 'normal')

def __init__(self, bpy_face, mesh, matrix=1):		def __init__(self, bpy_face, mesh, matrix=1):
self.data = bpy_face
self.index = bpy_face.index		self.index = bpy_face.index
self.edges = list()		self.edges = list()
self.verts = [mesh.verts[i] for i in bpy_face.vertices]		self.verts = [mesh.verts[i] for i in bpy_face.vertices]
self.loop_start = bpy_face.loop_start		self.loop_start = bpy_face.loop_start
self.area = bpy_face.area		self.area = bpy_face.area
self.uvface = None		self.uvface = None

#TODO: would be nice to reuse the existing normal if possible		# calculate the face normal explicitly
if len(self.verts) == 3:		if len(self.verts) == 3:
# normal of a triangle can be calculated directly		# normal of a triangle can be calculated directly
self.normal = (self.verts[1]-self.verts[0]).cross(self.verts[2]-self.verts[0]).normalized()		self.normal = (self.verts[1].co - self.verts[0].co).cross(self.verts[2].co - self.verts[0].co).normalized()
else:		else:
# Newell's method		# Newell's method
nor = M.Vector((0,0,0))		nor = M.Vector((0, 0, 0))
for a, b in pairs(self.verts):		for a, b in pairs(self.verts):
p, m = a+b, a-b		p, m = a.co + b.co, a.co - b.co
nor.x, nor.y, nor.z = nor.x+m.yp.z, nor.y+m.zp.x, nor.z+m.x*p.y		nor.x, nor.y, nor.z = nor.x + m.yp.z, nor.y + m.zp.x, nor.z + m.x*p.y
self.normal = nor.normalized()		self.normal = nor.normalized()

for verts_indices in bpy_face.edge_keys:		for verts_indices in bpy_face.edge_keys:
edge = mesh.edges_by_verts_indices[verts_indices]		edge = mesh.edges_by_verts_indices[verts_indices]
self.edges.append(edge)		self.edges.append(edge)
edge.faces.append(self)		edge.faces.append(self)

def is_twisted(self):		def is_twisted(self):
if len(self.verts) > 3:		if len(self.verts) > 3:
center = vectavg(self.verts)		center = sum(vertex.co for vertex in self.verts) / len(self.verts)
plane_d = center.dot(self.normal)		plane_d = center.dot(self.normal)
diameter = max((center-vertex.co).length for vertex in self.verts)		diameter = max((center - vertex.co).length for vertex in self.verts)
for vertex in self.verts:		for vertex in self.verts:
# check coplanarity		# check coplanarity
if abs(vertex.co.dot(self.normal) - plane_d) > diameter*0.01: #TODO: this threshold should be editable or well chosen at least		if abs(vertex.co.dot(self.normal) - plane_d) > diameter * 0.01:
return True		return True
return False		return False

def __hash__(self):		def __hash__(self):
return hash(self.index)		return hash(self.index)


class Island:		class Island:
		"""Part of the net to be exported"""
		__slots__ = ('faces', 'edges', 'verts', 'fake_verts',
		'uvverts_by_id', 'boundary', 'has_safe_geometry',
		'pos', 'offset', 'angle', 'is_placed', 'bounding_box',
		'image_path', 'embedded_image',
		'number', 'label', 'abbreviation', 'title', 'is_inside_out',
		'scale', 'markers', 'sticker_numbering')

def __init__(self, face=None):		def __init__(self, face=None):
"""Create an Island from a single Face"""		"""Create an Island from a single Face"""
self.faces=list()		self.faces = list()
self.edges=set()		self.edges = set()
self.verts=set()		self.verts = set()
self.fake_verts = list()		self.fake_verts = list()
self.pos=M.Vector((0,0))		self.pos = M.Vector((0, 0))
self.offset=M.Vector((0,0))		self.offset = M.Vector((0, 0))
self.angle=0		self.angle = 0
self.is_placed=False		self.is_placed = False
self.bounding_box=M.Vector((0,0))		self.bounding_box = M.Vector((0, 0))

self.image_path = None		self.image_path = None
self.embedded_image = None		self.embedded_image = None

self.label = None		self.label = None
self.abbreviation = None		self.abbreviation = None
self.title = None		self.title = None
self.is_inside_out = False # swaps concave <-> convex edges		self.is_inside_out = False # swaps concave <-> convex edges

if face:		if face:
uvface = UVFace(face, self)		uvface = UVFace(face, self)
self.verts.update(uvface.verts)		self.verts.update(uvface.verts)
self.faces.append(uvface)		self.faces.append(uvface)

# speedup for Island.join		# speedup for Island.join
self.uvverts_by_id = {uvvertex.vertex.index: [uvvertex] for uvvertex in self.verts}		self.uvverts_by_id = {uvvertex.vertex.index: [uvvertex] for uvvertex in self.verts}
		# UVEdges on the boundary
self.boundary_sorted = list(self.edges) # UVEdges on the boundary, sorted left to right		self.boundary = list(self.edges)
self.boundary_sorted.sort(key = lambda uvedge: uvedge.min.tup, reverse = True)		self.has_safe_geometry = True

self.scale = 1		self.scale = 1
self.markers = list()		self.markers = list()
self.sticker_numbering = 0		self.sticker_numbering = 0
self.label = None		self.label = None

def join(self, other, edge:Edge, size_limit=None, epsilon=1e-6) -> bool:		def join(self, other, edge: Edge, size_limit=None, epsilon=1e-6) -> bool:
"""		"""
Try to join other island on given edge		Try to join other island on given edge
Returns False if they would overlap		Returns False if they would overlap
"""		"""

class Intersection(Exception):		class Intersection(Exception):
pass		pass

def is_below(self: UVEdge, other: UVEdge, cross=cross_product):		class GeometryError(Exception):
		pass

		def is_below(self, other, correct_geometry=True):
if self is other:		if self is other:
return False		return False
if self.top < other.bottom:		if self.top < other.bottom:
return True		return True
if other.top < self.bottom:		if other.top < self.bottom:
return False		return False
if self.max.tup <= other.min.tup:		if self.max.tup <= other.min.tup:
return True		return True
if other.max.tup <= self.min.tup:		if other.max.tup <= self.min.tup:
return False		return False
self_vector = self.max.co - self.min.co		self_vector = self.max.co - self.min.co
min_to_min = other.min.co - self.min.co		min_to_min = other.min.co - self.min.co
cross_b1 = cross(self_vector, min_to_min)		cross_b1 = self_vector.cross(min_to_min)
cross_b2 = cross(self_vector, (other.max.co - self.min.co))		cross_b2 = self_vector.cross(other.max.co - self.min.co)
if cross_b1 != 0 or cross_b2 != 0:		if cross_b2 < cross_b1:
if cross_b1 >= 0 and cross_b2 >= 0:		cross_b1, cross_b2 = cross_b2, cross_b1
		if cross_b2 > 0 and (cross_b1 > 0 or (cross_b1 == 0 and not self.is_uvface_upwards())):
return True		return True
if cross_b1 <= 0 and cross_b2 <= 0:		if cross_b1 < 0 and (cross_b2 < 0 or (cross_b2 == 0 and self.is_uvface_upwards())):
return False		return False
other_vector = other.max.co - other.min.co		other_vector = other.max.co - other.min.co
cross_a1 = cross(other_vector, -min_to_min)		cross_a1 = other_vector.cross(-min_to_min)
cross_a2 = cross(other_vector, (self.max.co - other.min.co))		cross_a2 = other_vector.cross(self.max.co - other.min.co)
if cross_a1 != 0 or cross_a2 != 0:		if cross_a2 < cross_a1:
if cross_a1 <= 0 and cross_a2 <= 0:		cross_a1, cross_a2 = cross_a2, cross_a1
return True		if cross_a2 > 0 and (cross_a1 > 0 or (cross_a1 == 0 and not other.is_uvface_upwards())):
if cross_a1 >= 0 and cross_a2 >= 0:
return False		return False
		if cross_a1 < 0 and (cross_a2 < 0 or (cross_a2 == 0 and other.is_uvface_upwards())):
		return True
if cross_a1 == cross_b1 == cross_a2 == cross_b2 == 0:		if cross_a1 == cross_b1 == cross_a2 == cross_b2 == 0:
# an especially ugly special case -- lines lying on top of each other. Try to resolve instead of throwing an intersection:		if correct_geometry:
return self.min.tup < other.min.tup or (self.min.co+self.max.co).to_tuple() < (other.min.co+other.max.co).to_tuple()		raise GeometryError
raise Intersection()		elif self.is_uvface_upwards() == other.is_uvface_upwards():
		raise Intersection
		return False
		if self.min.tup == other.min.tup or self.max.tup == other.max.tup:
		return cross_a2 > cross_b2
		raise Intersection

class Sweepline:		class QuickSweepline:
		"""Efficient sweepline based on binary search, checking neighbors only"""
def __init__(self):		def __init__(self):
self.children = blist()		self.children = blist()

def add(self, item, cmp = is_below):		def add(self, item, cmp=is_below):
low = 0; high = len(self.children)		low, high = 0, len(self.children)
while low < high:		while low < high:
mid = (low + high) // 2		mid = (low + high) // 2
if cmp(self.children[mid], item):		if cmp(self.children[mid], item):
low = mid + 1		low = mid + 1
else:		else:
high = mid		high = mid
# check for intersections
if low > 0:
assert cmp(self.children[low-1], item)
if low < len(self.children):
assert not cmp(self.children[low], item)
self.children.insert(low, item)		self.children.insert(low, item)

def remove(self, item, cmp = is_below):		def remove(self, item, cmp=is_below):
index = self.children.index(item)		index = self.children.index(item)
self.children.pop(index)		self.children.pop(index)
if index > 0 and index < len(self.children):		if index > 0 and index < len(self.children):
# check for intersection		# check for intersection
assert not cmp(self.children[index], self.children[index-1])		if cmp(self.children[index], self.children[index-1]):
		raise GeometryError

		class BruteSweepline:
		"""Safe sweepline which checks all its members pairwise"""
		def __init__(self):
		self.children = set()
		self.last_min = None, []
		self.last_max = None, []

		def add(self, item, cmp=is_below):
		for child in self.children:
		if child.min is not item.min and child.max is not item.max:
		cmp(item, child, False)
		self.children.add(item)

		def remove(self, item):
		self.children.remove(item)

		def sweep(sweepline, segments):
		"""Sweep across the segments and raise an exception if necessary"""
		# careful, 'segments' may be a use-once iterator
		events_add = sorted(segments, reverse=True, key=lambda uvedge: uvedge.min.tup)
		events_remove = sorted(events_add, reverse=True, key=lambda uvedge: uvedge.max.tup)
		while events_remove:
		while events_add and events_add[-1].min.tup <= events_remove[-1].max.tup:
		sweepline.add(events_add.pop())
		sweepline.remove(events_remove.pop())

def root_find(value, tree):		def root_find(value, tree):
"""Find the root of a given value in a forest-like dictionary		"""Find the root of a given value in a forest-like dictionary
also updates the dictionary using path compression"""		also updates the dictionary using path compression"""
parent, relink = tree.get(value), list()		parent, relink = tree.get(value), list()
while parent is not None:		while parent is not None:
relink.append(value)		relink.append(value)
value, parent = parent, tree.get(parent)		value, parent = parent, tree.get(parent)
tree.update(dict.fromkeys(relink, value))		tree.update(dict.fromkeys(relink, value))
return value		return value

		def slope_from(position):
		def slope(uvedge):
		vec = (uvedge.vb.co - uvedge.va.co) if uvedge.va.tup == position else (uvedge.va.co - uvedge.vb.co)
		return (vec.y / vec.length + 1) if ((vec.x, vec.y) > (0, 0)) else (-1 - vec.y / vec.length)
		return slope

# find edge in other and in self		# find edge in other and in self
for uvedge in edge.uvedges:		for uvedge in edge.uvedges:
if uvedge in self.edges:		if uvedge.uvface.face in uvedge.edge.main_faces:
		if uvedge.uvface.island is self and uvedge in self.boundary:
uvedge_a = uvedge		uvedge_a = uvedge
elif uvedge in other.edges:		elif uvedge.uvface.island is other and uvedge in other.boundary:
uvedge_b = uvedge		uvedge_b = uvedge
#DEBUG		else:
assert uvedge_a is not uvedge_b		return False

# check if vertices and normals are aligned correctly		# check if vertices and normals are aligned correctly
verts_flipped = uvedge_b.va.vertex is uvedge_a.va.vertex		verts_flipped = uvedge_b.va.vertex is uvedge_a.va.vertex
flipped = verts_flipped ^ uvedge_a.uvface.flipped ^ uvedge_b.uvface.flipped		flipped = verts_flipped ^ uvedge_a.uvface.flipped ^ uvedge_b.uvface.flipped
# determine rotation		# determine rotation
# NOTE: if the edges differ in length, the matrix will involve uniform scaling. May happen in the case of twisted n-gons		# NOTE: if the edges differ in length, the matrix will involve uniform scaling.
		# Such situation may occur in the case of twisted n-gons
first_b, second_b = (uvedge_b.va, uvedge_b.vb) if not verts_flipped else (uvedge_b.vb, uvedge_b.va)		first_b, second_b = (uvedge_b.va, uvedge_b.vb) if not verts_flipped else (uvedge_b.vb, uvedge_b.va)
if not flipped:		if not flipped:
rot = fitting_matrix(first_b.co - second_b.co, uvedge_a.vb.co - uvedge_a.va.co)		rot = fitting_matrix(first_b.co - second_b.co, uvedge_a.vb.co - uvedge_a.va.co)
else:		else:
flip = M.Matrix(((-1,0),(0,1)))		flip = M.Matrix(((-1, 0), (0, 1)))
rot = fitting_matrix(flip * (first_b.co - second_b.co), uvedge_a.vb.co - uvedge_a.va.co) * flip		rot = fitting_matrix(flip * (first_b.co - second_b.co), uvedge_a.vb.co - uvedge_a.va.co) * flip
trans = uvedge_a.vb.co - rot * first_b.co		trans = uvedge_a.vb.co - rot * first_b.co
# extract and transform island_b's boundary		# extract and transform island_b's boundary
phantoms = {uvvertex: UVVertex(rot*uvvertex.co+trans, uvvertex.vertex) for uvvertex in other.verts}		phantoms = {uvvertex: UVVertex(rot*uvvertex.co + trans, uvvertex.vertex) for uvvertex in other.verts}

# check the size of the resulting island		# check the size of the resulting island
if size_limit:		if size_limit:
# first check: bounding box		# first check: bounding box
# FIXME! this is wrong: self.boundary_sorted[-1].max.co.x need _not_ be the rightmost vertex		bbox_width = max(max(seg.max.co.x for seg in self.boundary), max(vertex.co.x for vertex in phantoms)) - min(min(seg.min.co.x for seg in self.boundary), min(vertex.co.x for vertex in phantoms))
bbox_width = max(self.boundary_sorted[-1].max.co.x, max(vertex.co.x for vertex in phantoms)) - min(self.boundary_sorted[0].min.co.x, min(vertex.co.x for vertex in phantoms))		bbox_height = max(max(seg.top for seg in self.boundary), max(vertex.co.y for vertex in phantoms)) - min(min(seg.bottom for seg in self.boundary), min(vertex.co.y for vertex in phantoms))
bbox_height = max(max(seg.top for seg in self.boundary_sorted), max(vertex.co.y for vertex in phantoms)) - min(min(seg.bottom for seg in self.boundary_sorted), min(vertex.co.y for vertex in phantoms))
if min(bbox_width, bbox_height)2 > size_limit.x2 + size_limit.y**2:		if min(bbox_width, bbox_height)2 > size_limit.x2 + size_limit.y**2:
return False		return False
if (bbox_width > size_limit.x or bbox_height > size_limit.y) and (bbox_height > size_limit.x or bbox_width > size_limit.y):		if (bbox_width > size_limit.x or bbox_height > size_limit.y) and (bbox_height > size_limit.x or bbox_width > size_limit.y):
# further checks (FIXME!)		# further checks (TODO!)
# for the time being, just throw this piece away		# for the time being, just throw this piece away
return False		return False

assert edge.vect.length > 0		distance_limit = edge.vect.length_squared * epsilon
distance_limit = edge.vect.length * epsilon
# try and merge UVVertices closer than sqrt(distance_limit)		# try and merge UVVertices closer than sqrt(distance_limit)
empty = tuple()
merged_uvedges = set()		merged_uvedges = set()
		merged_uvedge_pairs = list()

# merge all uvvertices that are close enough using a union-find structure		# merge all uvvertices that are close enough using a union-find structure
# uvvertices will be merged only in cases other->self and self->self		# uvvertices will be merged only in cases other->self and self->self
# all resulting groups are merged together to a uvvertex of self		# all resulting groups are merged together to a uvvertex of self
is_merged_mine = False		is_merged_mine = False
shared_vertices = self.uvverts_by_id.keys() & other.uvverts_by_id.keys()		shared_vertices = self.uvverts_by_id.keys() & other.uvverts_by_id.keys()
for vertex_id in shared_vertices:		for vertex_id in shared_vertices:
uvs = self.uvverts_by_id[vertex_id] + other.uvverts_by_id[vertex_id]		uvs = self.uvverts_by_id[vertex_id] + other.uvverts_by_id[vertex_id]
len_mine = len(self.uvverts_by_id[vertex_id])		len_mine = len(self.uvverts_by_id[vertex_id])
merged = dict()		merged = dict()
for i, a in enumerate(uvs[:len_mine]):		for i, a in enumerate(uvs[:len_mine]):
i = root_find(i, merged)		i = root_find(i, merged)
for j, b in enumerate(uvs[i+1:], i+1):		for j, b in enumerate(uvs[i+1:], i+1):
b = b if j < len_mine else phantoms[b]		b = b if j < len_mine else phantoms[b]
j = root_find(j, merged)		j = root_find(j, merged)
if i == j:		if i == j:
continue		continue
i, j = (j, i) if j < i else (i, j)		i, j = (j, i) if j < i else (i, j)
		campbellbartonUnsubmitted Not Done Inline Actions Much more efficient to simply do `present.clear()` campbellbarton: Much more efficient to simply do `present.clear()`
		emuAuthorUnsubmitted Not Done Inline Actions I don't think that would work. There may be other unrelated items in the list `present`. Each vertex may have many instances in the flat net. This code really needs to make sure that `source` is not in `present`, and that `target` is. emu: I don't think that would work. There may be other unrelated items in the list `present`. Each…
if (a.co - b.co).length_squared < distance_limit:		if (a.co - b.co).length_squared < distance_limit:
merged[j] = i		merged[j] = i
for source, target in merged.items():		for source, target in merged.items():
target = root_find(target, merged)		target = root_find(target, merged)
phantoms[uvs[source]] = uvs[target]		phantoms[uvs[source]] = uvs[target]
is_merged_mine \|= (source < len_mine) # remember that a vertex of this island has been merged		is_merged_mine \|= (source < len_mine) # remember that a vertex of this island has been merged

for uvedge in (chain(self.boundary_sorted, other.boundary_sorted) if is_merged_mine else other.boundary_sorted):		for uvedge in (chain(self.boundary, other.boundary) if is_merged_mine else other.boundary):
for partner in uvedge.edge.uvedges:		for partner in uvedge.edge.uvedges:
if partner is not uvedge:		if partner is not uvedge:
# TODO: make sure that this code is okay
paired_a, paired_b = phantoms.get(partner.vb, partner.vb), phantoms.get(partner.va, partner.va)		paired_a, paired_b = phantoms.get(partner.vb, partner.vb), phantoms.get(partner.va, partner.va)
if (partner.uvface.flipped ^ flipped) != uvedge.uvface.flipped:		if (partner.uvface.flipped ^ flipped) != uvedge.uvface.flipped:
paired_a, paired_b = paired_b, paired_a		paired_a, paired_b = paired_b, paired_a
if phantoms.get(uvedge.va, uvedge.va) is paired_a and phantoms.get(uvedge.vb, uvedge.vb) is paired_b:		if phantoms.get(uvedge.va, uvedge.va) is paired_a and phantoms.get(uvedge.vb, uvedge.vb) is paired_b:
		# if these two edges will get merged, add them both to the set
merged_uvedges.update((uvedge, partner))		merged_uvedges.update((uvedge, partner))
		merged_uvedge_pairs.append((uvedge, partner))
break		break

if uvedge_b not in merged_uvedges:		if uvedge_b not in merged_uvedges:
raise UnfoldError("Export failed. Please report this error, including the model if you can.")		raise UnfoldError("Export failed. Please report this error, including the model if you can.")

boundary_other = [UVEdge(phantoms[uvedge.va], phantoms[uvedge.vb], self) for uvedge in other.boundary_sorted if uvedge not in merged_uvedges]		boundary_other = [PhantomUVEdge(phantoms[uvedge.va], phantoms[uvedge.vb], flipped ^ uvedge.uvface.flipped)
# TODO: if is_merged_mine, it might make sense to create a similar list from self.boundary sorted as well		for uvedge in other.boundary if uvedge not in merged_uvedges]
		# TODO: if is_merged_mine, it might make sense to create a similar list from self.boundary as well

		incidence = {vertex.tup for vertex in phantoms.values()}.intersection(vertex.tup for vertex in self.verts)
		incidence = {position: list() for position in incidence} # from now on, 'incidence' is a dict
		for uvedge in chain(boundary_other, self.boundary):
		for vertex in (uvedge.va, uvedge.vb):
		site = incidence.get(vertex.tup)
		if site is not None:
		site.append(uvedge)
		for position, segments in incidence.items():
		if len(segments) <= 2:
		continue
		segments.sort(key=slope_from(position))
		for right, left in pairs(segments):
		is_left_ccw = left.is_uvface_upwards() ^ (left.max.tup == position)
		is_right_ccw = right.is_uvface_upwards() ^ (right.max.tup == position)
		if is_right_ccw and not is_left_ccw and type(right) is not type(left) and right not in merged_uvedges and left not in merged_uvedges:
		return False
		if (not is_right_ccw and right not in merged_uvedges) ^ (is_left_ccw and left not in merged_uvedges):
		return False

# check for self-intersections: create event list		# check for self-intersections
sweepline = Sweepline()
events_add = [uvedge for uvedge in chain(boundary_other, self.boundary_sorted)]
events_remove = list(events_add)
events_add.sort(key = lambda uvedge: uvedge.min.tup, reverse = True)
events_remove.sort(key = lambda uvedge: uvedge.max.tup, reverse = True)
try:		try:
while events_remove:		try:
while events_add and events_add[-1].min.tup <= events_remove[-1].max.tup:		sweepline = QuickSweepline() if self.has_safe_geometry and other.has_safe_geometry else BruteSweepline()
sweepline.add(events_add.pop())		sweep(sweepline, (uvedge for uvedge in chain(boundary_other, self.boundary)))
sweepline.remove(events_remove.pop())		self.has_safe_geometry &= other.has_safe_geometry
		except GeometryError:
		sweep(BruteSweepline(), (uvedge for uvedge in chain(boundary_other, self.boundary)))
		self.has_safe_geometry = False
except Intersection:		except Intersection:
return False		return False

# mark all edges that connect the islands as not cut		# mark all edges that connect the islands as not cut
for uvedge in merged_uvedges:		for uvedge in merged_uvedges:
uvedge.edge.is_main_cut = False		uvedge.edge.is_main_cut = False

# include all trasformed vertices as mine		# include all trasformed vertices as mine
self.verts.update(phantoms.values())		self.verts.update(phantoms.values())

# update the uvverts_by_id dictionary		# update the uvverts_by_id dictionary
for source, target in phantoms.items():		for source, target in phantoms.items():
present = self.uvverts_by_id.get(target.vertex.index)		present = self.uvverts_by_id.get(target.vertex.index)
if not present:		if not present:
self.uvverts_by_id[target.vertex.index] = [target]		self.uvverts_by_id[target.vertex.index] = [target]
else:		else:
if target not in present:		# emulation of set behavior... sorry, it is faster
present.append(target)
if source in present:		if source in present:
present.remove(source)		present.remove(source)
		if target not in present:
		present.append(target)

# re-link uvedges and uvfaces to their transformed locations		# re-link uvedges and uvfaces to their transformed locations
for uvedge in other.edges:		for uvedge in other.edges:
uvedge.island = self		uvedge.island = self
uvedge.va = phantoms[uvedge.va]		uvedge.va = phantoms[uvedge.va]
uvedge.vb = phantoms[uvedge.vb]		uvedge.vb = phantoms[uvedge.vb]
uvedge.update()		uvedge.update()
if is_merged_mine:		if is_merged_mine:
for uvedge in self.edges:		for uvedge in self.edges:
uvedge.va = phantoms.get(uvedge.va, uvedge.va)		uvedge.va = phantoms.get(uvedge.va, uvedge.va)
uvedge.vb = phantoms.get(uvedge.vb, uvedge.vb)		uvedge.vb = phantoms.get(uvedge.vb, uvedge.vb)
self.edges.update(other.edges)		self.edges.update(other.edges)

for uvface in other.faces:		for uvface in other.faces:
uvface.island = self		uvface.island = self
uvface.verts = [phantoms[uvvertex] for uvvertex in uvface.verts]		uvface.verts = [phantoms[uvvertex] for uvvertex in uvface.verts]
uvface.uvvertex_by_id = {index: phantoms[uvvertex] for index, uvvertex in uvface.uvvertex_by_id.items()}		uvface.uvvertex_by_id = {index: phantoms[uvvertex]
		for index, uvvertex in uvface.uvvertex_by_id.items()}
uvface.flipped ^= flipped		uvface.flipped ^= flipped
if is_merged_mine:		if is_merged_mine:
		# there may be own uvvertices that need to be replaced by phantoms
for uvface in self.faces:		for uvface in self.faces:
if any(uvvertex in phantoms for uvvertex in uvface.verts):		if any(uvvertex in phantoms for uvvertex in uvface.verts):
uvface.verts = [phantoms.get(uvvertex, uvvertex) for uvvertex in uvface.verts]		uvface.verts = [phantoms.get(uvvertex, uvvertex) for uvvertex in uvface.verts]
uvface.uvvertex_by_id = {index: phantoms.get(uvvertex, uvvertex) for index, uvvertex in uvface.uvvertex_by_id.items()}		uvface.uvvertex_by_id = {index: phantoms.get(uvvertex, uvvertex)
		for index, uvvertex in uvface.uvvertex_by_id.items()}
self.faces.extend(other.faces)		self.faces.extend(other.faces)

self.boundary_sorted = [uvedge for uvedge in chain(self.boundary_sorted, other.boundary_sorted) if uvedge not in merged_uvedges]		self.boundary = [uvedge for uvedge in
self.boundary_sorted.sort(key = lambda uvedge: uvedge.min.tup)		chain(self.boundary, other.boundary) if uvedge not in merged_uvedges]

		for uvedge, partner in merged_uvedge_pairs:
		# make sure that main faces are the ones actually merged (this changes nothing in most cases)
		uvedge.edge.main_faces[:] = uvedge.uvface.face, partner.uvface.face

# everything seems to be OK		# everything seems to be OK
return True		return True

def add_marker(self, marker):		def add_marker(self, marker):
self.fake_verts.extend(marker.bounds)		self.fake_verts.extend(marker.bounds)
self.markers.append(marker)		self.markers.append(marker)

def convex_hull(self) -> list:		def convex_hull(self) -> list:
"""Returns a list of Vectors that forms the best fitting convex polygon."""		"""Returns a list of Vectors that forms the best fitting convex polygon."""
def make_convex_curve(points, cross=cross_product):		def make_convex_curve(points):
"""Remove points from given vert list so that the result poly is a convex curve (works for both top and bottom)."""		"""Remove points from given vert list so that the result poly is a convex curve (works for both top and bottom)."""
result = list()		result = list()
for point in points:		for point in points:
while len(result) >= 2 and cross((point - result[-1]), (result[-1] - result[-2])) >= 0:		while len(result) >= 2 and (point - result[-1]).cross(result[-1] - result[-2]) >= 0:
result.pop()		result.pop()
result.append(point)		result.append(point)
return result		return result
points = list(self.fake_verts)		points = list(self.fake_verts)
points.extend(vertex.co for vertex in self.verts)		points.extend(vertex.co for vertex in self.verts)
points.sort(key=lambda point: point.x)		points.sort(key=lambda point: point.x)
points_top = make_convex_curve(points)		points_top = make_convex_curve(points)
points_bottom = make_convex_curve(reversed(points))		points_bottom = make_convex_curve(reversed(points))
#remove left and right ends and concatenate the lists to form a polygon in the right order		# remove left and right ends and concatenate the lists to form a polygon in the correct order
return points_top[:-1] + points_bottom[:-1]		return points_top[:-1] + points_bottom[:-1]

def generate_bounding_box(self, space_at_bottom=0):		def generate_bounding_box(self, space_at_bottom=0, aspect_ratio=1):
"""Find the rotation for the optimal bounding box and calculate its dimensions."""		"""Calculate the rotation for a quite good bounding box"""
def bounding_box_score(size):		def bounding_box_score(size):
"""Calculate the score - the bigger result, the better box."""		"""Calculate the score - the bigger result, the better box."""
return 1/(size.x*size.y)		return 1/max(size.x, size.y * aspect_ratio)
points_convex = self.convex_hull()		points_convex = self.convex_hull()
if not points_convex:		if not points_convex:
raise UnfoldError("Error, check topology of the mesh object (failed to calculate a convex hull)")		raise UnfoldError("Topology error. Try to remove doubled vertices and faces.")
#go through all edges and search for the best solution		# go through all edges and search for the best solution
best_score = 0		best_score = 0
best_box = (0, M.Vector((0,0)), M.Vector((0,0))) #(angle, box, offset) for the best score		best_box = (0, M.Vector((0, 0)), M.Vector((0, 0))) # (angle, box, offset) for the best score
		direction_x = M.Vector((1, 0))
for point_a, point_b in pairs(points_convex):		for point_a, point_b in pairs(points_convex):
if point_a == point_b:		angle = direction_x.angle_signed(point_b - point_a, None)
		if angle is None:
continue		continue
angle = angle2d(point_b - point_a)
rot = M.Matrix.Rotation(angle, 2)		rot = M.Matrix.Rotation(angle, 2)
#find the dimensions in both directions		# find the dimensions in both directions
rotated = [rot*point for point in points_convex]		rotated = [rot * point for point in points_convex]
bottom_left = M.Vector((min(v.x for v in rotated), min(v.y for v in rotated)))		bottom_left = M.Vector((min(v.x for v in rotated), min(v.y for v in rotated)))
top_right = M.Vector((max(v.x for v in rotated), max(v.y for v in rotated)))		top_right = M.Vector((max(v.x for v in rotated), max(v.y for v in rotated)))
box = top_right - bottom_left		box = top_right - bottom_left
score = bounding_box_score(box)		score = bounding_box_score(box)
if score > best_score:		if score > best_score:
best_box = angle, box, bottom_left		best_box = angle, box, bottom_left
best_score = score		best_score = score
angle, box, offset = best_box		angle, box, offset = best_box
#switch the box so that it is taller than wider
if box.x > box.y:
angle += pi/2
offset = M.Vector((-offset.y-box.y, offset.x))
box = box.yx
box.y += space_at_bottom		box.y += space_at_bottom
offset.y -= space_at_bottom		offset.y -= space_at_bottom
self.angle = angle		self.angle = angle
self.bounding_box = box		self.bounding_box = box
self.offset = -offset		self.offset = -offset

def apply_scale(self, scale=1):		def apply_scale(self, scale):
		"""Multiply all coordinates belonging to this Island by the given scale"""
if scale != 1:		if scale != 1:
self.scale *= scale		self.scale *= scale
for vertex in self.verts:		for vertex in self.verts:
vertex.co *= scale		vertex.co *= scale
for point in self.fake_verts:		for point in self.fake_verts:
point *= scale		point *= scale

def generate_label(self, label=None, abbreviation=None):		def generate_label(self, label=None, abbreviation=None):
		"""Assign a name to this island automatically"""
abbr = abbreviation or self.abbreviation or str(self.number)		abbr = abbreviation or self.abbreviation or str(self.number)
# TODO: dots should be added in the last instant when outputting any text		# TODO: dots should be added in the last instant when outputting any text
if not set('69NZMWpbqd').isdisjoint(abbr) and set('6890oOxXNZMWIlpbqd').issuperset(abbr):		if not set('69NZMWpbqd').isdisjoint(abbr) and set('6890oOxXNZMWIlpbqd').issuperset(abbr):
abbr += "."		abbr += "."
self.label = label or self.label or "Island {}".format(self.number)		self.label = label or self.label or "Island {}".format(self.number)
self.abbreviation = abbr		self.abbreviation = abbr

def save_uv(self, tex, aspect_ratio=1):		def save_uv(self, tex, aspect_ratio=1):
"""Save UV Coordinates of all UVFaces to a given UV texture		"""Save UV Coordinates of all UVFaces to a given UV texture
tex: UV Texture layer to use (BPy MeshUVLoopLayer struct)		tex: UV Texture layer to use (BPy MeshUVLoopLayer struct)
page_size: size of the page in pixels (vector)"""		page_size: size of the page in pixels (vector)"""
texface = tex.data		texface = tex.data
for uvface in self.faces:		for uvface in self.faces:
rot = M.Matrix.Rotation(self.angle, 2)		rot = M.Matrix.Rotation(self.angle, 2)
for i, uvvertex in enumerate(uvface.verts):		for i, uvvertex in enumerate(uvface.verts):
uv = rot * uvvertex.co + self.offset + self.pos		uv = rot * uvvertex.co + self.offset + self.pos
texface[uvface.face.loop_start + i].uv[0] = uv.x / aspect_ratio		texface[uvface.face.loop_start + i].uv[0] = uv.x / aspect_ratio
texface[uvface.face.loop_start + i].uv[1] = uv.y		texface[uvface.face.loop_start + i].uv[1] = uv.y

def save_uv_separate(self, tex):		def save_uv_separate(self, tex):
"""Save UV Coordinates of all UVFaces to a given UV texture, spanning from 0 to 1		"""Save UV Coordinates of all UVFaces to a given UV texture, spanning from 0 to 1
tex: UV Texture layer to use (BPy MeshUVLoopLayer struct)		tex: UV Texture layer to use (BPy MeshUVLoopLayer struct)
page_size: size of the page in pixels (vector)"""		page_size: size of the page in pixels (vector)"""
texface = tex.data		texface = tex.data
scale_x, scale_y = 1/self.bounding_box.x, 1/self.bounding_box.y		scale_x, scale_y = 1 / self.bounding_box.x, 1 / self.bounding_box.y
for uvface in self.faces:		for uvface in self.faces:
rot = M.Matrix.Rotation(self.angle, 2)		rot = M.Matrix.Rotation(self.angle, 2)
for i, uvvertex in enumerate(uvface.verts):		for i, uvvertex in enumerate(uvface.verts):
uv = rot * uvvertex.co + self.offset		uv = rot * uvvertex.co + self.offset
texface[uvface.face.loop_start + i].uv[0] = uv.x * scale_x		texface[uvface.face.loop_start + i].uv[0] = uv.x * scale_x
texface[uvface.face.loop_start + i].uv[1] = uv.y * scale_y		texface[uvface.face.loop_start + i].uv[1] = uv.y * scale_y


class Page:		class Page:
"""Container for several Islands"""		"""Container for several Islands"""
		__slots__ = ('islands', 'name', 'image_path')

def __init__(self, num=1):		def __init__(self, num=1):
self.islands = list()		self.islands = list()
self.name = "page{}".format(num)		self.name = "page{}".format(num)
self.image_path = None		self.image_path = None


class UVVertex:		class UVVertex:
"""Vertex in 2D"""		"""Vertex in 2D"""
		__slots__ = ('co', 'vertex', 'tup')

def __init__(self, vector, vertex=None):		def __init__(self, vector, vertex=None):
if type(vector) is UVVertex: #Copy constructor		if isinstance(vector, UVVertex):
		# Copy constructor
self.co=vector.co.copy()		self.co = vector.co.copy()
self.vertex=vector.vertex		self.vertex = vector.vertex
else:		else:
self.co=(M.Vector(vector)).xy		self.co = vector.xy
self.vertex=vertex		self.vertex = vertex
self.tup = tuple(self.co)		self.tup = tuple(self.co)
def __str__(self):
		def __repr__(self):
if self.vertex:		if self.vertex:
return "UV "+str(self.vertex.index)+" ["+strf(self.co.x)+", "+strf(self.co.y)+"]"		return "UV {} [{:.3f}, {:.3f}]".format(self.vertex.index, self.co.x, self.co.y)
else:		else:
return "UV * ["+strf(self.co.x)+", "+strf(self.co.y)+"]"		return "UV * [{:.3f}, {:.3f}]".format(self.co.x, self.co.y)
def __repr__(self):
return str(self)

class UVEdge:		class UVEdge:
"""Edge in 2D"""		"""Edge in 2D"""
def __init__(self, vertex1:UVVertex, vertex2:UVVertex, island:Island, uvface=None, edge:Edge=None):		# Every UVEdge is attached to only one UVFace
		# UVEdges are doubled as needed because they both have to point clockwise around their faces
		__slots__ = ('va', 'vb', 'island', 'uvface', 'edge',
		'min', 'max', 'bottom', 'top',
		'neighbor_left', 'neighbor_right', 'sticker')

		def __init__(self, vertex1: UVVertex, vertex2: UVVertex, island: Island, uvface, edge):
self.va = vertex1		self.va = vertex1
self.vb = vertex2		self.vb = vertex2
self.update()		self.update()
self.island = island		self.island = island
self.uvface = uvface		self.uvface = uvface
		self.sticker = None
if edge:		if edge:
self.edge = edge		self.edge = edge
edge.uvedges.append(self)		edge.uvedges.append(self)
#Every UVEdge is attached to only one UVFace. UVEdges are doubled as needed, because they both have to point clockwise around their faces
def update(self):		def update(self):
"""Update data if UVVertices have moved"""		"""Update data if UVVertices have moved"""
self.min, self.max = (self.va, self.vb) if (self.va.tup < self.vb.tup) else (self.vb, self.va)		self.min, self.max = (self.va, self.vb) if (self.va.tup < self.vb.tup) else (self.vb, self.va)
y1, y2 = self.va.co.y, self.vb.co.y		y1, y2 = self.va.co.y, self.vb.co.y
self.bottom, self.top = (y1, y2) if y1 < y2 else (y2, y1)		self.bottom, self.top = (y1, y2) if y1 < y2 else (y2, y1)
def __str__(self):
return "({} - {})".format(self.va, self.vb)		def is_uvface_upwards(self):
		return (self.va.tup < self.vb.tup) ^ self.uvface.flipped

def __repr__(self):		def __repr__(self):
return str(self)		return "({0.va} - {0.vb})".format(self)


		class PhantomUVEdge:
		"""Temporary 2D Segment for calculations"""
		__slots__ = ('va', 'vb', 'min', 'max', 'bottom', 'top')

		def __init__(self, vertex1: UVVertex, vertex2: UVVertex, flip):
		self.va, self.vb = (vertex2, vertex1) if flip else (vertex1, vertex2)
		self.min, self.max = (self.va, self.vb) if (self.va.tup < self.vb.tup) else (self.vb, self.va)
		y1, y2 = self.va.co.y, self.vb.co.y
		self.bottom, self.top = (y1, y2) if y1 < y2 else (y2, y1)

		def is_uvface_upwards(self):
		return self.va.tup < self.vb.tup

		def __repr__(self):
		return "[{0.va} - {0.vb}]".format(self)


class UVFace:		class UVFace:
"""Face in 2D"""		"""Face in 2D"""
		__slots__ = ('verts', 'edges', 'face', 'island', 'flipped', 'uvvertex_by_id')

def __init__(self, face:Face, island:Island):		def __init__(self, face: Face, island: Island):
"""Creace an UVFace from a Face and a fixed edge.		"""Creace an UVFace from a Face and a fixed edge.
face: Face to take coordinates from		face: Face to take coordinates from
island: Island to register itself in		island: Island to register itself in
fixed_edge: Edge to connect to (that already has UV coordinates)"""		fixed_edge: Edge to connect to (that already has UV coordinates)"""
self.verts=list()		self.verts = list()
self.face=face		self.face = face
face.uvface=self		face.uvface = self
self.island=island		self.island = island
self.flipped = False # a flipped UVFace has edges clockwise		self.flipped = False # a flipped UVFace has edges clockwise

rot=z_up_matrix(face.normal)		rot = z_up_matrix(face.normal)
self.uvvertex_by_id=dict() #link vertex id -> UVVertex		self.uvvertex_by_id = dict() # link vertex id -> UVVertex
for vertex in face.verts:		for vertex in face.verts:
uvvertex=UVVertex(rot * vertex.co, vertex)		uvvertex = UVVertex(rot * vertex.co, vertex)
self.verts.append(uvvertex)		self.verts.append(uvvertex)
self.uvvertex_by_id[vertex.index]=uvvertex		self.uvvertex_by_id[vertex.index] = uvvertex
self.edges=list()		self.edges = list()
edge_by_verts=dict()		edge_by_verts = dict()
for edge in face.edges:		for edge in face.edges:
edge_by_verts[(edge.va.index, edge.vb.index)]=edge		edge_by_verts[(edge.va.index, edge.vb.index)] = edge
edge_by_verts[(edge.vb.index, edge.va.index)]=edge		edge_by_verts[(edge.vb.index, edge.va.index)] = edge
for va, vb in pairs(self.verts):		for va, vb in pairs(self.verts):
uvedge = UVEdge(va, vb, island, self, edge_by_verts[(va.vertex.index, vb.vertex.index)])		uvedge = UVEdge(va, vb, island, self, edge_by_verts[(va.vertex.index, vb.vertex.index)])
self.edges.append(uvedge)		self.edges.append(uvedge)
island.edges.add(uvedge)		island.edges.add(uvedge)


class Marker:		class Marker:
"""Various graphical elements linked to the net, but not being parts of the mesh"""		"""Various graphical elements linked to the net, but not being parts of the mesh"""
def __init__(self):		pass
self.bounds = list()

class Arrow(Marker):		class Arrow(Marker):
		"""Arrow denoting the number of the edge it points to"""
		__slots__ = ('bounds', 'center', 'rot', 'text', 'size')

def __init__(self, uvedge, size, index):		def __init__(self, uvedge, size, index):
self.text = str(index)		self.text = str(index)
edge = (uvedge.vb.co - uvedge.va.co) if not uvedge.uvface.flipped else (uvedge.va.co - uvedge.vb.co)		edge = (uvedge.vb.co - uvedge.va.co) if not uvedge.uvface.flipped else (uvedge.va.co - uvedge.vb.co)
self.center = (uvedge.va.co + uvedge.vb.co) / 2		self.center = (uvedge.va.co + uvedge.vb.co) / 2
self.size = size		self.size = size
sin, cos = edge.y/edge.length, edge.x/edge.length		sin, cos = edge.y / edge.length, edge.x / edge.length
self.rot = M.Matrix(((cos, -sin), (sin, cos)))		self.rot = M.Matrix(((cos, -sin), (sin, cos)))
tangent = edge.normalized()		tangent = edge.normalized()
normal = M.Vector((tangent.y, -tangent.x))		normal = M.Vector((tangent.y, -tangent.x))
self.bounds = [self.center, self.center + (1.2normal+tangent)size, self.center + (1.2normal-tangent)size]		self.bounds = [self.center, self.center + (1.2normal + tangent)size, self.center + (1.2normal - tangent)size]


class Sticker(Marker):		class Sticker(Marker):
"""Sticker face"""		"""Sticker face"""
		__slots__ = ('bounds', 'center', 'rot', 'text', 'width', 'vertices')

def __init__(self, uvedge, default_width=0.005, index=None, target_island=None):		def __init__(self, uvedge, default_width=0.005, index=None, target_island=None):
"""Sticker is directly attached to the given UVEdge"""		"""Sticker is directly attached to the given UVEdge"""
first_vertex, second_vertex = (uvedge.va, uvedge.vb) if not uvedge.uvface.flipped else (uvedge.vb, uvedge.va)		first_vertex, second_vertex = (uvedge.va, uvedge.vb) if not uvedge.uvface.flipped else (uvedge.vb, uvedge.va)
edge = first_vertex.co - second_vertex.co		edge = first_vertex.co - second_vertex.co
sticker_width=min(default_width, edge.length/2)		sticker_width = min(default_width, edge.length / 2)
other=uvedge.edge.other_uvedge(uvedge) #This is the other uvedge - the sticking target		other = uvedge.edge.other_uvedge(uvedge) # This is the other uvedge - the sticking target

other_first, other_second = (other.va, other.vb) if not other.uvface.flipped else (other.vb, other.va)		other_first, other_second = (other.va, other.vb) if not other.uvface.flipped else (other.vb, other.va)
other_edge = other_second.co - other_first.co		other_edge = other_second.co - other_first.co
cos_a=cos_b=0.5 #angle a is at vertex uvedge.va, b is at uvedge.vb		# angle a is at vertex uvedge.va, b is at uvedge.vb
		cos_a = cos_b = 0.5
sin_a=sin_b=0.75**0.5		sin_a = sin_b = 0.75**0.5
len_a=len_b=sticker_width/sin_a #len_a is length of the side adjacent to vertex a, len_b similarly		# len_a is length of the side adjacent to vertex a, len_b likewise
		len_a = len_b = sticker_width / sin_a
#fix overlaps with the most often neighbour - its sticking target		# fix overlaps with the most often neighbour - its sticking target
if first_vertex == other_second:		if first_vertex == other_second:
cos_a = min(max(cos_a, (edgeother_edge)/(edge.length*2)), 1) #angles between pi/3 and 0; fix for math errors		cos_a = max(cos_a, (edgeother_edge) / (edge.length*2)) # angles between pi/3 and 0
sin_a = (1-cos_a2)0.5		sin_a = abs(1 - cos_a2)0.5
len_b = min(len_a, (edge.lengthsin_a)/(sin_acos_b+sin_b*cos_a))		len_b = min(len_a, (edge.lengthsin_a) / (sin_acos_b + sin_b*cos_a))
len_a = 0 if sin_a == 0 else min(sticker_width/sin_a, (edge.length-len_b*cos_b)/cos_a)		len_a = 0 if sin_a == 0 else min(sticker_width / sin_a, (edge.length - len_b*cos_b) / cos_a)
elif second_vertex == other_first:		elif second_vertex == other_first:
cos_b = min(max(cos_b, (edgeother_edge)/(edge.length*2)), 1) #angles between pi/3 and 0; fix for math errors		cos_b = max(cos_b, (edgeother_edge) / (edge.length*2)) # angles between pi/3 and 0
sin_b = (1-cos_b2)0.5		sin_b = abs(1 - cos_b2)0.5
len_a = min(len_a, (edge.lengthsin_b)/(sin_acos_b+sin_b*cos_a))		len_a = min(len_a, (edge.lengthsin_b) / (sin_acos_b + sin_b*cos_a))
len_b = 0 if sin_b == 0 else min(sticker_width/sin_b, (edge.length-len_a*cos_a)/cos_b)		len_b = 0 if sin_b == 0 else min(sticker_width / sin_b, (edge.length - len_a*cos_a) / cos_b)
v3 = UVVertex(second_vertex.co + M.Matrix(((cos_b, -sin_b), (sin_b, cos_b))) * edge * len_b/edge.length)		v3 = UVVertex(second_vertex.co + M.Matrix(((cos_b, -sin_b), (sin_b, cos_b))) * edge * len_b / edge.length)
v4 = UVVertex(first_vertex.co + M.Matrix(((-cos_a, -sin_a), (sin_a, -cos_a))) * edge * len_a/edge.length)		v4 = UVVertex(first_vertex.co + M.Matrix(((-cos_a, -sin_a), (sin_a, -cos_a))) * edge * len_a / edge.length)
if v3.co != v4.co:		if v3.co != v4.co:
self.vertices=[second_vertex, v3, v4, first_vertex]		self.vertices = [second_vertex, v3, v4, first_vertex]
else:		else:
self.vertices=[second_vertex, v3, first_vertex]		self.vertices = [second_vertex, v3, first_vertex]

sin, cos = edge.y/edge.length, edge.x/edge.length		sin, cos = edge.y / edge.length, edge.x / edge.length
self.rot = M.Matrix(((cos, -sin), (sin, cos)))		self.rot = M.Matrix(((cos, -sin), (sin, cos)))
self.width = sticker_width * 0.9		self.width = sticker_width * 0.9
self.text = "{}:{}".format(target_island.abbreviation, index) if index and target_island is not uvedge.island else index or None		if index and target_island is not uvedge.island:
		self.text = "{}:{}".format(target_island.abbreviation, index)
		else:
		self.text = index
self.center = (uvedge.va.co + uvedge.vb.co) / 2 + self.rotM.Vector((0, self.width0.2))		self.center = (uvedge.va.co + uvedge.vb.co) / 2 + self.rotM.Vector((0, self.width0.2))
self.bounds = [v3.co, v4.co, self.center] if v3.co != v4.co else [v3.co, self.center]		self.bounds = [v3.co, v4.co, self.center] if v3.co != v4.co else [v3.co, self.center]


class NumberAlone(Marker):		class NumberAlone(Marker):
"""Numbering inside the island describing edges to be sticked"""		"""Numbering inside the island describing edges to be sticked"""
		__slots__ = ('bounds', 'center', 'rot', 'text', 'size')

def __init__(self, uvedge, index, default_size=0.005):		def __init__(self, uvedge, index, default_size=0.005):
"""Sticker is directly attached to the given UVEdge"""		"""Sticker is directly attached to the given UVEdge"""
edge = (uvedge.va - uvedge.vb) if not uvedge.uvface.flipped else (uvedge.vb - uvedge.va)		edge = (uvedge.va.co - uvedge.vb.co) if not uvedge.uvface.flipped else (uvedge.vb.co - uvedge.va.co)

self.size = default_size# min(default_size, edge.length/2)		self.size = default_size
sin, cos = edge.y/edge.length, edge.x/edge.length		sin, cos = edge.y / edge.length, edge.x / edge.length
self.rot = M.Matrix(((cos, -sin), (sin, cos)))		self.rot = M.Matrix(((cos, -sin), (sin, cos)))
self.text = index		self.text = index
self.center = (uvedge.va.co + uvedge.vb.co) / 2 - self.rotM.Vector((0, self.size1.2))		self.center = (uvedge.va.co + uvedge.vb.co) / 2 - self.rotM.Vector((0, self.size1.2))
self.bounds = [self.center]		self.bounds = [self.center]


class SVG:		class SVG:
"""Simple SVG exporter"""		"""Simple SVG exporter"""

def __init__(self, page_size_pixels:M.Vector, scale, style, pure_net=True):		def __init__(self, page_size_pixels: M.Vector, scale, style, pure_net=True):
"""Initialize document settings.		"""Initialize document settings.
page_size_pixels: document dimensions in pixels		page_size_pixels: document dimensions in pixels
pure_net: if True, do not use image"""		pure_net: if True, do not use image"""
self.page_size = page_size_pixels		self.page_size = page_size_pixels
self.scale = scale		self.scale = scale
self.pure_net = pure_net		self.pure_net = pure_net
self.style = style		self.style = style
self.margin = 0		self.margin = 0

def format_vertex(self, vector, rot=1, pos=M.Vector((0,0))):		def format_vertex(self, vector, rot=1, pos=M.Vector((0, 0))):
"""Return a string with both coordinates of the given vertex."""		"""Return a string with both coordinates of the given vertex."""
vector = rot*vector + pos		vector = rot*vector + pos
return str((vector.x)self.scale + self.margin) + " " + str((1-vector.y)self.scale+self.margin)		return "{:.6f} {:.6f}".format(vector.xself.scale + self.margin, (1-vector.y)self.scale + self.margin)

def write(self, mesh, filename):		def write(self, mesh, filename):
"""Write data to a file given by its name."""		"""Write data to a file given by its name."""
line_through = " L ".join #utility function		line_through = " L ".join # used for formatting of SVG path data
format_color = lambda vec: "#{:02x}{:02x}{:02x}".format(round(vec[0]255), round(vec[1]255), round(vec[2])*255)
format_style = {'SOLID':"none", 'DOT':"0.2,4", 'DASH':"4,8", 'LONGDASH':"6,3", 'DASHDOT':"8,4,2,4"}		format_style = {'SOLID': "none", 'DOT': "0.2,4", 'DASH': "4,8", 'LONGDASH': "6,3", 'DASHDOT': "8,4,2,4"}
rows = "\n".join		rows = "\n".join

styleargs = {name: format_color(getattr(self.style, name)) for name in ("outer_color", "outbg_color", "convex_color", "concave_color", "inbg_color", "sticker_fill", "sticker_color", "text_color")}		def format_color(vec):
styleargs.update({name: format_style[getattr(self.style, name)] for name in ("outer_style", "convex_style", "concave_style")})		return "#{:02x}{:02x}{:02x}".format(round(vec[0] * 255), round(vec[1] * 255), round(vec[2] * 255))
styleargs.update({name: getattr(self.style, attr)[3] for name, attr in (("outer_alpha", "outer_color"), ("outbg_alpha", "outbg_color"), ("convex_alpha", "convex_color"), ("concave_alpha", "concave_color"), ("inbg_alpha", "inbg_color"), ("sticker_alpha", "sticker_fill"), ("text_alpha", "text_color"))})
styleargs.update({name: getattr(self.style, name) for name in ("outer_width", "convex_width", "concave_width", "sticker_width")})		def format_matrix(matrix):
styleargs.update({"outbg_width": self.style.outer_widthself.style.outbg_width, "convexbg_width": self.style.convex_widthself.style.inbg_width, "concavebg_width": self.style.concave_width*self.style.inbg_width})		return " ".join(" ".join(map(str, column)) for column in matrix)

		def path_convert(string, relto=os_path.dirname(filename)):
		assert(os_path) # check the module was imported
		string = os_path.relpath(string, relto)
		if os_path.sep != '/':
		string = string.replace(os_path.sep, '/')
		return string

		styleargs = {name: format_color(getattr(self.style, name)) for name in
		("outer_color", "outbg_color", "convex_color", "concave_color",
		"inbg_color", "sticker_fill", "text_color")}
		styleargs.update({name: format_style[getattr(self.style, name)] for name in
		("outer_style", "convex_style", "concave_style")})
		styleargs.update({name: getattr(self.style, attr)[3] for name, attr in
		(("outer_alpha", "outer_color"), ("outbg_alpha", "outbg_color"),
		("convex_alpha", "convex_color"), ("concave_alpha", "concave_color"),
		("inbg_alpha", "inbg_color"), ("sticker_alpha", "sticker_fill"),
		("text_alpha", "text_color"))})
		styleargs.update({name: getattr(self.style, name) for name in
		("outer_width", "convex_width", "concave_width")})
		styleargs.update({"outbg_width": self.style.outer_width * self.style.outbg_width,
		"convexbg_width": self.style.convex_width * self.style.inbg_width,
		"concavebg_width": self.style.concave_width * self.style.inbg_width})
for num, page in enumerate(mesh.pages):		for num, page in enumerate(mesh.pages):
with open(filename+"_"+page.name+".svg", 'w') as f:		with open("{}_{}.svg".format(filename, page.name), 'w') as f:
f.write("<?xml version='1.0' encoding='UTF-8' standalone='no'?>\n")		print(self.svg_base.format(width=self.page_size.x, height=self.page_size.y), file=f)
f.write("<svg xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' version='1.1' x='0px' y='0px' width='" + str(self.page_size.x) + "px' height='" + str(self.page_size.y) + "px'>")		print(self.css_base.format(**styleargs), file=f)
f.write("""<style type="text/css">
path {{fill:none; stroke-width:{outer_width:.2}px; stroke-linecap:square; stroke-linejoin:bevel; stroke-dasharray:none}}
path.outer {{stroke:{outer_color}; stroke-dasharray:{outer_style}; stroke-dashoffset:0; stroke-width:{outer_width:.2}px; stroke-opacity: {outer_alpha:.2}}}
path.convex {{stroke:{convex_color}; stroke-dasharray:{convex_style}; stroke-dashoffset:0; stroke-width:{convex_width:.2}px; stroke-opacity: {convex_alpha:.2}}}
path.concave {{stroke:{concave_color}; stroke-dasharray:{concave_style}; stroke-dashoffset:0; stroke-width:{concave_width:.2}px; stroke-opacity: {concave_alpha:.2}}}
path.outer_background {{stroke:{outbg_color}; stroke-opacity:{outbg_alpha}; stroke-width:{outbg_width:.2}px}}
path.convex_background {{stroke:{inbg_color}; stroke-opacity:{inbg_alpha}; stroke-width:{convexbg_width:.2}px}}
path.concave_background {{stroke:{inbg_color}; stroke-opacity:{inbg_alpha}; stroke-width:{concavebg_width:.2}px}}
path.sticker {{fill: {sticker_fill}; stroke: {sticker_color}; fill-opacity: {sticker_alpha:.2}; stroke-width:{sticker_width:.2}; stroke-opacity: 1}}
path.arrow {{fill: #000;}}
text {{font-size: 12px; font-style: normal; fill: {text_color}; fill-opacity: {text_alpha:.2}; stroke: none;}}
text.scaled {{font-size: 1px;}}
tspan {{text-anchor:middle;}}
</style>""".format(**styleargs))
if page.image_path:		if page.image_path:
f.write("<image transform='matrix(1 0 0 1 {margin} {margin})' width='{}' height='{}' xlink:href='file://{}'/>\n".format(self.page_size.x-2self.margin, self.page_size.y-2self.margin, page.image_path, margin=self.margin))		print(self.image_linked_tag.format(
		pos="{0} {0}".format(self.margin),
		width=self.page_size.x - 2*self.margin,
		height=self.page_size.y - 2*self.margin,
		path=path_convert(page.image_path)),
		file=f)
if len(page.islands) > 1:		if len(page.islands) > 1:
f.write("<g>")		print("<g>", file=f)
for island in page.islands:		for island in page.islands:
f.write("<g>")		print("<g>", file=f)
if island.image_path:		if island.image_path:
f.write("<image transform='translate({pos})' width='{width}' height='{height}' xlink:href='file://{path}'/>\n".format(		print(self.image_linked_tag.format(
pos=self.format_vertex(island.pos + M.Vector((0, island.bounding_box.y))), width=island.bounding_box.xself.scale, height=island.bounding_box.yself.scale,		pos=self.format_vertex(island.pos + M.Vector((0, island.bounding_box.y))),
path=island.image_path))		width=island.bounding_box.x*self.scale,
		height=island.bounding_box.y*self.scale,
		path=path_convert(island.image_path)),
		file=f)
elif island.embedded_image:		elif island.embedded_image:
f.write("<image transform='translate({pos})' width='{width}' height='{height}' xlink:href='data:image/png;base64,".format(		print(self.image_embedded_tag.format(
pos=self.format_vertex(island.pos + M.Vector((0, island.bounding_box.y))), width=island.bounding_box.xself.scale, height=island.bounding_box.yself.scale,		pos=self.format_vertex(island.pos + M.Vector((0, island.bounding_box.y))),
path=island.image_path))		width=island.bounding_box.x*self.scale,
f.write(island.embedded_image)		height=island.bounding_box.y*self.scale,
f.write("'/>\n")		path=island.image_path),
		island.embedded_image, "'/>",
		file=f, sep="")

rot = M.Matrix.Rotation(island.angle, 2)		rot = M.Matrix.Rotation(island.angle, 2)
pos = island.pos + island.offset		pos = island.pos + island.offset

		if island.title:
		print(self.text_tag.format(
		x=self.scale * (island.bounding_box.x*0.5 + island.pos.x) + self.margin,
		y=self.scale * (1 - island.pos.y) + self.margin,
		label=island.title), file=f)

		data_markers = list()
		data_stickerfill = list()
		for marker in island.markers:
		if isinstance(marker, Sticker):
		data_stickerfill.append("M {} Z".format(
		line_through(self.format_vertex(vertex.co, rot, pos) for vertex in marker.vertices)))
		if marker.text:
		data_markers.append(self.text_scaled_tag.format(
		label=marker.text,
		pos=self.format_vertex(marker.center, rot, pos),
		mat=format_matrix(marker.width * island.scale * self.scale * rot * marker.rot)))
		elif isinstance(marker, Arrow):
		size = marker.size * island.scale * self.scale
		position = marker.center + marker.rotmarker.sizeisland.scale*M.Vector((0, -0.9))
		data_markers.append(self.arrow_marker_tag.format(
		index=marker.text,
		arrow_pos=self.format_vertex(marker.center, rot, pos),
		scale=size,
		pos=self.format_vertex(position, rot, pos - marker.sizeisland.scaleM.Vector((0, 0.4))),
		mat=format_matrix(size * rot * marker.rot)))
		elif isinstance(marker, NumberAlone):
		size = marker.size * island.scale * self.scale
		data_markers.append(self.text_scaled_tag.format(
		label=marker.text,
		pos=self.format_vertex(marker.center, rot, pos),
		mat=format_matrix(size * rot * marker.rot)))
		if data_stickerfill and self.style.sticker_fill[3] > 0:
		print("<path class='sticker' d='", rows(data_stickerfill), "'/>", file=f)

data_outer, data_convex, data_concave = list(), list(), list()		data_outer, data_convex, data_concave = list(), list(), list()
		outer_edges = set(island.boundary)
		while outer_edges:
		data_loop = list()
		uvedge = outer_edges.pop()
		while 1:
		if uvedge.sticker:
		data_loop.extend(self.format_vertex(vertex.co, rot, pos) for vertex in uvedge.sticker.vertices[1:])
		else:
		vertex = uvedge.vb if uvedge.uvface.flipped else uvedge.va
		data_loop.append(self.format_vertex(vertex.co, rot, pos))
		uvedge = uvedge.neighbor_right
		try:
		outer_edges.remove(uvedge)
		except KeyError:
		break
		data_outer.append("M {} Z".format(line_through(data_loop)))

for uvedge in island.edges:		for uvedge in island.edges:
edge = uvedge.edge		edge = uvedge.edge
data_uvedge = "M " + line_through((self.format_vertex(vertex.co, rot, pos) for vertex in (uvedge.va, uvedge.vb)))		if edge.is_cut(uvedge.uvface.face) and not uvedge.sticker:
if not edge.is_cut(uvedge.uvface.face):		continue
if uvedge.uvface.flipped ^ (uvedge.va.vertex.index > uvedge.vb.vertex.index): # each uvedge is in two opposite-oriented variants; we want to add each only once		data_uvedge = "M {}".format(
		line_through(self.format_vertex(vertex.co, rot, pos) for vertex in (uvedge.va, uvedge.vb)))
		# each uvedge is in two opposite-oriented variants; we want to add each only once
		if uvedge.sticker or uvedge.uvface.flipped != (uvedge.va.vertex.index > uvedge.vb.vertex.index):
if edge.angle > 0.01:		if edge.angle > 0.01:
data_convex.append(data_uvedge)		data_convex.append(data_uvedge)
elif edge.angle < -0.01:		elif edge.angle < -0.01:
data_concave.append(data_uvedge)		data_concave.append(data_uvedge)
else:
data_outer.append(data_uvedge)
if island.is_inside_out:		if island.is_inside_out:
data_convex, data_concave = data_concave, data_convex		data_convex, data_concave = data_concave, data_convex

if data_convex:		if data_convex:
if not self.pure_net and self.style.use_inbg:		if not self.pure_net and self.style.use_inbg:
f.write("<path class='convex_background' d='" + rows(data_convex) + "'/>")		print("<path class='convex_background' d='", rows(data_convex), "'/>", file=f)
f.write("<path class='convex' d='" + rows(data_convex) + "'/>")		print("<path class='convex' d='", rows(data_convex), "'/>", file=f)
if data_concave:		if data_concave:
if not self.pure_net and self.style.use_inbg:		if not self.pure_net and self.style.use_inbg:
f.write("<path class='concave_background' d='" + rows(data_concave) + "'/>")		print("<path class='concave_background' d='", rows(data_concave), "'/>", file=f)
f.write("<path class='concave' d='" + rows(data_concave) + "'/>")		print("<path class='concave' d='", rows(data_concave), "'/>", file=f)
if data_outer:		if data_outer:
if not self.pure_net and self.style.use_outbg:		if not self.pure_net and self.style.use_outbg:
f.write("<path class='outer_background' d='" + rows(data_outer) + "'/>")		print("<path class='outer_background' d='", rows(data_outer), "'/>", file=f)
f.write("<path class='outer' d='" + rows(data_outer) + "'/>")		print("<path class='outer' d='", rows(data_outer), "'/>", file=f)

if island.title:
f.write("<text transform='translate({x} {y})'><tspan>{label}</tspan></text>".format(
x=self.scale * (island.bounding_box.x0.5 + island.pos.x) + self.margin, y=self.scale (1 - island.pos.y) + self.margin,
label=island.title))
data_markers = list()
format_matrix = lambda mat: " ".join(" ".join(map(str, col)) for col in mat)
for marker in island.markers:
if type(marker) is Sticker:
if self.do_create_stickers:
text = "<text class='scaled' transform='matrix({mat} {pos})'><tspan>{index}</tspan></text>".format(
index=marker.text,
pos=self.format_vertex(marker.center, rot, pos),
mat=format_matrix(marker.width * island.scale * self.scale * rot * marker.rot)) if marker.text else ""
data_markers.append("<g><path class='sticker' d='M {data} Z'/>{text}</g>".format(
data=line_through((self.format_vertex(vertex.co, rot, pos) for vertex in marker.vertices)),
text=text))
elif marker.text:
data_markers.append("<text class='scaled' transform='matrix({mat} {pos})'><tspan>{index}</tspan></text>".format(
index=marker.text,
pos=self.format_vertex(marker.center, rot, pos),
mat=format_matrix(marker.width * island.scale * self.scale * rot * marker.rot)))
elif type(marker) is Arrow:
size = marker.size * island.scale * self.scale
data_markers.append("<g><path transform='matrix({mat} {arrow_pos})' class='arrow' d='M 0 0 L 1 1 L 0 0.25 L -1 1 Z'/><text class='scaled' transform='matrix({scale} 0 0 {scale} {pos})'><tspan>{index}</tspan></text></g>".format(
index=marker.text,
arrow_pos=self.format_vertex(marker.center, rot, pos),
scale=size,
pos=self.format_vertex(marker.center + marker.rotmarker.sizeisland.scaleM.Vector((0, -0.9)), rot, pos - marker.sizeisland.scale*M.Vector((0, 0.4))),
mat=format_matrix(size * rot * marker.rot)))
elif type(marker) is NumberAlone:
size = marker.size * island.scale * self.scale
data_markers.append("<text class='scaled' transform='matrix({mat} {pos})'><tspan>{index}</tspan></text>".format(
index=marker.text,
pos=self.format_vertex(marker.center, rot, pos),
mat=format_matrix(size * rot * marker.rot)))
if data_markers:		if data_markers:
f.write("<g>" + rows(data_markers) + "</g>") #Stickers are separate paths in one group		print(rows(data_markers), file=f)
f.write("</g>")		print("</g>", file=f)


if len(page.islands) > 1:		if len(page.islands) > 1:
f.write("</g>")		print("</g>", file=f)
f.write("</svg>")		print("</svg>", file=f)

		image_linked_tag = "<image transform='translate({pos})' width='{width}' height='{height}' xlink:href='{path}'/>"
		image_embedded_tag = "<image transform='translate({pos})' width='{width}' height='{height}' xlink:href='data:image/png;base64,"
		text_tag = "<text transform='translate({x} {y})'><tspan>{label}</tspan></text>"
		text_scaled_tag = "<text class='scaled' transform='matrix({mat} {pos})'><tspan>{label}</tspan></text>"
		arrow_marker_tag = "<g><path transform='matrix({mat} {arrow_pos})' class='arrow' d='M 0 0 L 1 1 L 0 0.25 L -1 1 Z'/>" \
		"<text class='scaled' transform='matrix({scale} 0 0 {scale} {pos})'><tspan>{index}</tspan></text></g>"

		svg_base = """<?xml version='1.0' encoding='UTF-8' standalone='no'?>
		<svg xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' version='1.1'
		x='0px' y='0px' width='{width}px' height='{height}px'>"""

		css_base = """<style type="text/css">
		path {{
		fill: none;
		stroke-width: {outer_width:.2}px;
		stroke-linecap: square;
		stroke-linejoin: bevel;
		stroke-dasharray: none;
		}}
		path.outer {{
		stroke: {outer_color};
		stroke-dasharray: {outer_style};
		stroke-dashoffset: 0;
		stroke-width: {outer_width:.2}px;
		stroke-opacity: {outer_alpha:.2};
		}}
		path.convex {{
		stroke: {convex_color};
		stroke-dasharray: {convex_style};
		stroke-dashoffset:0;
		stroke-width:{convex_width:.2}px;
		stroke-opacity: {convex_alpha:.2}
		}}
		path.concave {{
		stroke: {concave_color};
		stroke-dasharray: {concave_style};
		stroke-dashoffset: 0;
		stroke-width: {concave_width:.2}px;
		stroke-opacity: {concave_alpha:.2}
		}}
		path.outer_background {{
		stroke: {outbg_color};
		stroke-opacity: {outbg_alpha};
		stroke-width: {outbg_width:.2}px
		}}
		path.convex_background {{
		stroke: {inbg_color};
		stroke-opacity: {inbg_alpha};
		stroke-width: {convexbg_width:.2}px
		}}
		path.concave_background {{
		stroke:{inbg_color};
		stroke-opacity:{inbg_alpha};
		stroke-width:{concavebg_width:.2}px
		}}
		path.sticker {{
		fill: {sticker_fill};
		stroke: none;
		fill-opacity: {sticker_alpha:.2};
		}}
		path.arrow {{
		fill: #000;
		}}
		text {{
		font-size: 12px;
		font-style: normal;
		fill: {text_color};
		fill-opacity: {text_alpha:.2};
		stroke: none;
		}}
		text.scaled {{
		font-size: 1px;
		}}
		tspan {{
		text-anchor:middle;
		}}
		</style>"""

class MakeUnfoldable(bpy.types.Operator):

		class Unfold(bpy.types.Operator):
"""Blender Operator: unfold the selected object."""		"""Blender Operator: unfold the selected object."""
bl_idname = "mesh.make_unfoldable"
bl_label = "Make Unfoldable"		bl_idname = "mesh.unfold"
		bl_label = "Unfold"
bl_description = "Mark seams so that the mesh can be exported as a paper model"		bl_description = "Mark seams so that the mesh can be exported as a paper model"
bl_options = {'REGISTER', 'UNDO'}		bl_options = {'REGISTER', 'UNDO'}
edit = bpy.props.BoolProperty(name="", description="", default=False, options={'HIDDEN'})		edit = bpy.props.BoolProperty(name="", description="", default=False, options={'HIDDEN'})
priority_effect_convex = bpy.props.FloatProperty(name="Priority Convex", description="Priority effect for edges in convex angles", default=default_priority_effect['CONVEX'], soft_min=-1, soft_max=10, subtype='FACTOR')		priority_effect_convex = bpy.props.FloatProperty(name="Priority Convex",
priority_effect_concave = bpy.props.FloatProperty(name="Priority Concave", description="Priority effect for edges in concave angles", default=default_priority_effect['CONCAVE'], soft_min=-1, soft_max=10, subtype='FACTOR')		description="Priority effect for edges in convex angles",
priority_effect_length = bpy.props.FloatProperty(name="Priority Length", description="Priority effect of edge length", default=default_priority_effect['LENGTH'], soft_min=-10, soft_max=1, subtype='FACTOR')		default=default_priority_effect['CONVEX'], soft_min=-1, soft_max=10, subtype='FACTOR')
do_create_uvmap = bpy.props.BoolProperty(name="Create UVMap", description="Create a new UV Map showing the islands and page layout", default=False)		priority_effect_concave = bpy.props.FloatProperty(name="Priority Concave",
		description="Priority effect for edges in concave angles",
		default=default_priority_effect['CONCAVE'], soft_min=-1, soft_max=10, subtype='FACTOR')
		priority_effect_length = bpy.props.FloatProperty(name="Priority Length",
		description="Priority effect of edge length",
		default=default_priority_effect['LENGTH'], soft_min=-10, soft_max=1, subtype='FACTOR')
		do_create_uvmap = bpy.props.BoolProperty(name="Create UVMap",
		description="Create a new UV Map showing the islands and page layout", default=False)
unfolder = None		unfolder = None

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

def draw(self, context):		def draw(self, context):
layout = self.layout		layout = self.layout
col = layout.column()		col = layout.column()
col.active = not self.unfolder or len(self.unfolder.mesh.data.uv_textures) < 8		col.active = not self.unfolder or len(self.unfolder.mesh.data.uv_textures) < 8
col.prop(self.properties, "do_create_uvmap")		col.prop(self.properties, "do_create_uvmap")
layout.label(text="Edge Cutting Factors:")		layout.label(text="Edge Cutting Factors:")
col = layout.column(align=True)		col = layout.column(align=True)
col.label(text="Face Angle:")		col.label(text="Face Angle:")
col.prop(self.properties, "priority_effect_convex", text="Convex")		col.prop(self.properties, "priority_effect_convex", text="Convex")
col.prop(self.properties, "priority_effect_concave", text="Concave")		col.prop(self.properties, "priority_effect_concave", text="Concave")
layout.prop(self.properties, "priority_effect_length", text="Edge Length")		layout.prop(self.properties, "priority_effect_length", text="Edge Length")

def execute(self, context):		def execute(self, context):
sce = bpy.context.scene		sce = bpy.context.scene
		settings = sce.paper_model
recall_mode = context.object.mode		recall_mode = context.object.mode
bpy.ops.object.mode_set(mode='OBJECT')		bpy.ops.object.mode_set(mode='OBJECT')
recall_display_islands, sce.paper_model.display_islands = sce.paper_model.display_islands, False		recall_display_islands, sce.paper_model.display_islands = sce.paper_model.display_islands, False

ob = context.active_object		ob = context.active_object
mesh = context.active_object.data		mesh = context.active_object.data

page_size = M.Vector((0.210, 0.297)) if sce.paper_model.limit_by_page else None		page_size = M.Vector((settings.output_size_x, settings.output_size_y)) if settings.limit_by_page else None
priority_effect = {'CONVEX': self.priority_effect_convex, 'CONCAVE': self.priority_effect_concave, 'LENGTH': self.priority_effect_length}		priority_effect = {'CONVEX': self.priority_effect_convex,'CONCAVE': self.priority_effect_concave, 'LENGTH': self.priority_effect_length}
self.unfolder = unfolder = Unfolder(ob)		self.unfolder = unfolder = Unfolder(ob)
unfolder.prepare(page_size=page_size, mark_seams=True, create_uvmap=self.do_create_uvmap, priority_effect=priority_effect)		unfolder.prepare(page_size=page_size, mark_seams=True, create_uvmap=self.do_create_uvmap, priority_effect=priority_effect, scale=sce.unit_settings.scale_length/settings.scale)
if mesh.paper_island_list:		if mesh.paper_island_list:
self.unfolder.copy_island_names(mesh.paper_island_list)		self.unfolder.copy_island_names(mesh.paper_island_list)

island_list = mesh.paper_island_list		island_list = mesh.paper_island_list
island_list.clear() #remove previously defined islands		island_list.clear() # remove previously defined islands
for island in unfolder.mesh.islands:		for island in unfolder.mesh.islands:
#add islands to UI list and set default descriptions		# add islands to UI list and set default descriptions
list_item = island_list.add()		list_item = island_list.add()

#add faces' IDs to the island		# add faces' IDs to the island
for uvface in island.faces:		for uvface in island.faces:
lface = list_item.faces.add()		lface = list_item.faces.add()
lface.id = uvface.face.index		lface.id = uvface.face.index

# name must be set afterwards because it invokes an update callback		# name must be set afterwards because it invokes an update callback
list_item["abbreviation"] = island.abbreviation or "?"		list_item["abbreviation"] = island.abbreviation or "?"
list_item.label = island.label or "No Name"		list_item.label = island.label or "No Name"
#list_item.name = "{} ({} faces)".format(island.label, len(island.faces))
mesh.paper_island_index = -1		mesh.paper_island_index = -1

unfolder.mesh.data.show_edge_seams = True		unfolder.mesh.data.show_edge_seams = True
bpy.ops.object.mode_set(mode=recall_mode)		bpy.ops.object.mode_set(mode=recall_mode)
sce.paper_model.display_islands = recall_display_islands		sce.paper_model.display_islands = recall_display_islands
return {'FINISHED'}		return {'FINISHED'}


		class ClearAllSeams(bpy.types.Operator):
		"""Blender Operator: clear all seams of the active Mesh and all its unfold data"""

		bl_idname = "mesh.clear_all_seams"
		bl_label = "Clear All Seams"
		bl_description = "Clear all the seams and unfolded islands of the active object"

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

		def execute(self, context):
		ob = context.active_object
		mesh = ob.data

		for edge in mesh.edges:
		edge.use_seam = False
		mesh.paper_island_list.clear()

		return {'FINISHED'}


def page_size_preset_changed(self, context):		def page_size_preset_changed(self, context):
"""Update the actual document size to correct values"""		"""Update the actual document size to correct values"""
if self.page_size_preset == 'A4':		if self.page_size_preset == 'A4':
self.output_size_x = 0.210		self.output_size_x = 0.210
self.output_size_y = 0.297		self.output_size_y = 0.297
elif self.page_size_preset == 'A3':		elif self.page_size_preset == 'A3':
self.output_size_x = 0.297		self.output_size_x = 0.297
self.output_size_y = 0.420		self.output_size_y = 0.420
elif self.page_size_preset == 'US_LETTER':		elif self.page_size_preset == 'US_LETTER':
self.output_size_x = 0.216		self.output_size_x = 0.216
self.output_size_y = 0.279		self.output_size_y = 0.279
elif self.page_size_preset == 'US_LEGAL':		elif self.page_size_preset == 'US_LEGAL':
self.output_size_x = 0.216		self.output_size_x = 0.216
self.output_size_y = 0.356		self.output_size_y = 0.356


class PaperModelStyle(bpy.types.PropertyGroup):		class PaperModelStyle(bpy.types.PropertyGroup):
line_styles = [		line_styles = [
('SOLID', "Solid (----)", "Solid line"),		('SOLID', "Solid (----)", "Solid line"),
('DOT', "Dots (. . .)", "Dotted line"),		('DOT', "Dots (. . .)", "Dotted line"),
('DASH', "Short Dashes (- - -)", "Solid line"),		('DASH', "Short Dashes (- - -)", "Solid line"),
('LONGDASH', "Long Dashes (-- --)", "Solid line"),		('LONGDASH', "Long Dashes (-- --)", "Solid line"),
('DASHDOT', "Dash-dotted (-- .)", "Solid line")]		('DASHDOT', "Dash-dotted (-- .)", "Solid line")
outer_color = bpy.props.FloatVectorProperty(name="Outer Lines", description="Color of net outline", default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)		]
outer_style = bpy.props.EnumProperty(name="Outer Lines Drawing Style", description="Drawing style of net outline", default='SOLID', items=line_styles)		outer_color = bpy.props.FloatVectorProperty(name="Outer Lines",
outer_width = bpy.props.FloatProperty(name="Outer Lines Thickness", description="Thickness of net outline, in pixels", default=1.5, min=0, soft_max=10, precision=1)		description="Color of net outline",
use_outbg = bpy.props.BoolProperty(name="Highlight Outer Lines", description="Add another line below every line to improve contrast", default=True)		default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)
outbg_color = bpy.props.FloatVectorProperty(name="Outer Highlight", description="Color of the highlight for outer lines", default=(1.0, 1.0, 1.0, 1.0), min=0, max=1, subtype='COLOR', size=4)		outer_style = bpy.props.EnumProperty(name="Outer Lines Drawing Style",
outbg_width = bpy.props.FloatProperty(name="Outer Highlight Scale", description="Thickness of the highlighting lines as a multiple of the outer line", default=1.5, min=1, soft_max=3, subtype='FACTOR')		description="Drawing style of net outline",
		default='SOLID', items=line_styles)
convex_color = bpy.props.FloatVectorProperty(name="Inner Convex Lines", description="Color of lines to be folded to a convex angle", default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)		outer_width = bpy.props.FloatProperty(name="Outer Lines Thickness",
convex_style = bpy.props.EnumProperty(name="Convex Lines Drawing Style", description="Drawing style of lines to be folded to a convex angle", default='DASH', items=line_styles)		description="Thickness of net outline, in pixels",
convex_width = bpy.props.FloatProperty(name="Convex Lines Thickness", description="Thickness of concave lines, in pixels", default=1, min=0, soft_max=10, precision=1)		default=1.5, min=0, soft_max=10, precision=1)
concave_color = bpy.props.FloatVectorProperty(name="Inner Concave Lines", description="Color of lines to be folded to a concave angle", default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)		use_outbg = bpy.props.BoolProperty(name="Highlight Outer Lines",
concave_style = bpy.props.EnumProperty(name="Concave Lines Drawing Style", description="Drawing style of lines to be folded to a concave angle", default='DASHDOT', items=line_styles)		description="Add another line below every line to improve contrast",
concave_width = bpy.props.FloatProperty(name="Concave Lines Thickness", description="Thickness of concave lines, in pixels", default=1, min=0, soft_max=10, precision=1)		default=True)
use_inbg = bpy.props.BoolProperty(name="Highlight Inner Lines", description="Add another line below every line to improve contrast", default=True)		outbg_color = bpy.props.FloatVectorProperty(name="Outer Highlight",
inbg_color = bpy.props.FloatVectorProperty(name="Inner Highlight", description="Color of the highlight for inner lines", default=(1.0, 1.0, 1.0, 1.0), min=0, max=1, subtype='COLOR', size=4)		description="Color of the highlight for outer lines",
inbg_width = bpy.props.FloatProperty(name="Inner Highlight Scale", description="Thickness of the highlighting lines as a multiple of the inner line", default=1, min=1, soft_max=3, subtype='FACTOR')		default=(1.0, 1.0, 1.0, 1.0), min=0, max=1, subtype='COLOR', size=4)
		outbg_width = bpy.props.FloatProperty(name="Outer Highlight Scale",
sticker_fill = bpy.props.FloatVectorProperty(name="Tabs Fill", description="Fill color of sticking tabs", default=(1.0, 1.0, 1.0, 0.4), min=0, max=1, subtype='COLOR', size=4)		description="Thickness of the highlighting lines as a multiple of the outer line",
		campbellbartonUnsubmitted Not Done Inline Actions I think this is a bit confusing, why not import `bmesh` and call `bmesh.new` ? campbellbarton: I think this is a bit confusing, why not import `bmesh` and call `bmesh.new` ?
		emuAuthorUnsubmitted Not Done Inline Actions this way seemed to look more like Python to me, but I should better just conform with the API. I'll change it to bmesh.new emu: this way seemed to look more like Python to me, but I should better just conform with the API.
		emuAuthorUnsubmitted Not Done Inline Actions Or perhaps I'll just remove this function for now. It's commented out from the UI. I have this functionality in a branch, but it will take a few more weeks to finish. emu: Or perhaps I'll just remove this function for now. It's commented out from the UI. I have this…
sticker_color = bpy.props.FloatVectorProperty(name="Tabs Outline", description="Outline color of sticking tabs", default=(0.0, 0.0, 0.0), min=0, max=1, subtype='COLOR', size=3)		default=1.5, min=1, soft_max=3, subtype='FACTOR')
sticker_width = bpy.props.FloatProperty(name="Tabs Outline Thickness", description="Thickness of tabs outer line, in pixels", default=1, min=0, soft_max=10, precision=1)
text_color = bpy.props.FloatVectorProperty(name="Text Color", description="Color of all text used in the document", default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)		convex_color = bpy.props.FloatVectorProperty(name="Inner Convex Lines",
		description="Color of lines to be folded to a convex angle",
		default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)
		convex_style = bpy.props.EnumProperty(name="Convex Lines Drawing Style",
		description="Drawing style of lines to be folded to a convex angle",
		default='DASH', items=line_styles)
		convex_width = bpy.props.FloatProperty(name="Convex Lines Thickness",
		description="Thickness of concave lines, in pixels",
		default=1, min=0, soft_max=10, precision=1)
		concave_color = bpy.props.FloatVectorProperty(name="Inner Concave Lines",
		description="Color of lines to be folded to a concave angle",
		default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)
		concave_style = bpy.props.EnumProperty(name="Concave Lines Drawing Style",
		description="Drawing style of lines to be folded to a concave angle",
		default='DASHDOT', items=line_styles)
		concave_width = bpy.props.FloatProperty(name="Concave Lines Thickness",
		description="Thickness of concave lines, in pixels",
		default=1, min=0, soft_max=10, precision=1)
		use_inbg = bpy.props.BoolProperty(name="Highlight Inner Lines",
		description="Add another line below every line to improve contrast",
		default=True)
		inbg_color = bpy.props.FloatVectorProperty(name="Inner Highlight",
		description="Color of the highlight for inner lines",
		default=(1.0, 1.0, 1.0, 1.0), min=0, max=1, subtype='COLOR', size=4)
		inbg_width = bpy.props.FloatProperty(name="Inner Highlight Scale",
		description="Thickness of the highlighting lines as a multiple of the inner line",
		default=1, min=1, soft_max=3, subtype='FACTOR')

		sticker_fill = bpy.props.FloatVectorProperty(name="Tabs Fill",
		description="Fill color of sticking tabs",
		default=(0.9, 0.9, 0.9, 1.0), min=0, max=1, subtype='COLOR', size=4)
		text_color = bpy.props.FloatVectorProperty(name="Text Color",
		description="Color of all text used in the document",
		default=(0.0, 0.0, 0.0, 1.0), min=0, max=1, subtype='COLOR', size=4)
bpy.utils.register_class(PaperModelStyle)		bpy.utils.register_class(PaperModelStyle)


class ExportPaperModel(bpy.types.Operator):		class ExportPaperModel(bpy.types.Operator):
"""Blender Operator: save the selected object's net and optionally bake its texture"""		"""Blender Operator: save the selected object's net and optionally bake its texture"""

bl_idname = "export_mesh.paper_model"		bl_idname = "export_mesh.paper_model"
bl_label = "Export Paper Model"		bl_label = "Export Paper Model"
bl_description = "Export the selected object's net and optionally bake its texture"		bl_description = "Export the selected object's net and optionally bake its texture"
filepath = bpy.props.StringProperty(name="File Path", description="Target file to save the SVG")		filepath = bpy.props.StringProperty(name="File Path",
filename = bpy.props.StringProperty(name="File Name", description="Name of the file")		description="Target file to save the SVG")
directory = bpy.props.StringProperty(name="Directory", description="Directory of the file")		filename = bpy.props.StringProperty(name="File Name",
page_size_preset = bpy.props.EnumProperty(name="Page Size", description="Size of the exported document", default='A4', update=page_size_preset_changed, items=[		description="Name of the file")
		directory = bpy.props.StringProperty(name="Directory",
		description="Directory of the file")
		page_size_preset = bpy.props.EnumProperty(name="Page Size",
		description="Size of the exported document",
		default='A4', update=page_size_preset_changed, items=[
('USER', "User defined", "User defined paper size"),		('USER', "User defined", "User defined paper size"),
('A4', "A4", "International standard paper size"),		('A4', "A4", "International standard paper size"),
('A3', "A3", "International standard paper size"),		('A3', "A3", "International standard paper size"),
('US_LETTER', "Letter", "North American paper size"),		('US_LETTER', "Letter", "North American paper size"),
('US_LEGAL', "Legal", "North American paper size")])		('US_LEGAL', "Legal", "North American paper size")
output_size_x = bpy.props.FloatProperty(name="Page Width", description="Width of the exported document", default=0.210, soft_min=0.105, soft_max=0.841, subtype="UNSIGNED", unit="LENGTH")		])
output_size_y = bpy.props.FloatProperty(name="Page Height", description="Height of the exported document", default=0.297, soft_min=0.148, soft_max=1.189, subtype="UNSIGNED", unit="LENGTH")		output_size_x = bpy.props.FloatProperty(name="Page Width",
output_margin = bpy.props.FloatProperty(name="Page Margin", description="Distance from page borders to the printable area", default=0.005, min=0, soft_max=0.1, subtype="UNSIGNED", unit="LENGTH")		description="Width of the exported document",
output_dpi = bpy.props.FloatProperty(name="Unfolder DPI", description="Resolution of images and lines in pixels per inch", default=90, min=1, soft_min=30, soft_max=600, subtype="UNSIGNED")		default=0.210, soft_min=0.105, soft_max=0.841, subtype="UNSIGNED", unit="LENGTH")
output_type = bpy.props.EnumProperty(name="Textures", description="Source of a texture for the model", default='NONE', items=[		output_size_y = bpy.props.FloatProperty(name="Page Height",
		description="Height of the exported document",
		default=0.297, soft_min=0.148, soft_max=1.189, subtype="UNSIGNED", unit="LENGTH")
		output_margin = bpy.props.FloatProperty(name="Page Margin",
		description="Distance from page borders to the printable area",
		default=0.005, min=0, soft_max=0.1, subtype="UNSIGNED", unit="LENGTH")
		output_dpi = bpy.props.FloatProperty(name="Unfolder DPI",
		description="Resolution of images and lines in pixels per inch",
		default=90, min=1, soft_min=30, soft_max=600, subtype="UNSIGNED")
		output_type = bpy.props.EnumProperty(name="Textures",
		description="Source of a texture for the model",
		default='NONE', items=[
('NONE', "No Texture", "Export the net only"),		('NONE', "No Texture", "Export the net only"),
('TEXTURE', "Face Texture", "Export the active texture as it is in the 3D View"),		('TEXTURE', "Face Texture", "Export the active texture as it is in the 3D View"),
('RENDER', "Full Render", "Render the material of the model, including all illumination"),		('RENDER', "Full Render", "Render the material of the model, including all illumination"),
('SELECTED_TO_ACTIVE', "Selected to Active", "Use the selected surrounding objects as a texture")])		('SELECTED_TO_ACTIVE', "Selected to Active", "Use the selected surrounding objects as a texture")
do_create_stickers = bpy.props.BoolProperty(name="Create Tabs", description="Create gluing tabs around the net (useful for paper)", default=True)		])
do_create_numbers = bpy.props.BoolProperty(name="Create Numbers", description="Enumerate edges to make it clear which edges should be sticked together", default=True)		do_create_stickers = bpy.props.BoolProperty(name="Create Tabs",
sticker_width = bpy.props.FloatProperty(name="Tabs and Text Size", description="Width of gluing tabs and their numbers", default=0.005, soft_min=0, soft_max=0.05, subtype="UNSIGNED", unit="LENGTH")		description="Create gluing tabs around the net (useful for paper)",
image_packing = bpy.props.EnumProperty(name="Image Packing Method", description="Method of attaching baked image(s) to the SVG", default='PAGE_LINK', items=[		default=True)
		do_create_numbers = bpy.props.BoolProperty(name="Create Numbers",
		description="Enumerate edges to make it clear which edges should be sticked together",
		default=True)
		sticker_width = bpy.props.FloatProperty(name="Tabs and Text Size",
		description="Width of gluing tabs and their numbers",
		default=0.005, soft_min=0, soft_max=0.05, subtype="UNSIGNED", unit="LENGTH")
		image_packing = bpy.props.EnumProperty(name="Image Packing Method",
		description="Method of attaching baked image(s) to the SVG",
		default='PAGE_LINK', items=[
('PAGE_LINK', "Single Linked", "Bake one image per page of output"),		('PAGE_LINK', "Single Linked", "Bake one image per page of output"),
('ISLAND_LINK', "Linked", "Bake images separately for each island and save them in a directory"),		('ISLAND_LINK', "Linked", "Bake images separately for each island and save them in a directory"),
('ISLAND_EMBED', "Embedded", "Bake images separately for each island and embed them into the SVG")])		('ISLAND_EMBED', "Embedded", "Bake images separately for each island and embed them into the SVG")
scale = bpy.props.FloatProperty(name="Scale", description="Divisor of all dimensions when exporting", default=1, soft_min=1.0, soft_max=10000.0, subtype='UNSIGNED', precision=0)		])
do_create_uvmap = bpy.props.BoolProperty(name="Create UVMap", description="Create a new UV Map showing the islands and page layout", default=False)		scale = bpy.props.FloatProperty(name="Scale",
ui_expanded_document = bpy.props.BoolProperty(name="Show Document Settings Expanded", description="Shows the box 'Document Settings' expanded in user interface", default=True)		description="Divisor of all dimensions when exporting",
ui_expanded_style = bpy.props.BoolProperty(name="Show Style Settings Expanded", description="Shows the box 'Colors and Style' expanded in user interface", default=False)		default=1, soft_min=1.0, soft_max=10000.0, subtype='UNSIGNED', precision=0)
		do_create_uvmap = bpy.props.BoolProperty(name="Create UVMap",
		description="Create a new UV Map showing the islands and page layout",
		default=False)
		ui_expanded_document = bpy.props.BoolProperty(name="Show Document Settings Expanded",
		description="Shows the box 'Document Settings' expanded in user interface",
		default=True)
		ui_expanded_style = bpy.props.BoolProperty(name="Show Style Settings Expanded",
		description="Shows the box 'Colors and Style' expanded in user interface",
		default=False)
style = bpy.props.PointerProperty(type=PaperModelStyle)		style = bpy.props.PointerProperty(type=PaperModelStyle)

unfolder=None		unfolder = None
largest_island_ratio=0		largest_island_ratio = 0

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

def execute(self, context):		def execute(self, context):
try:		try:
if self.object.data.paper_island_list:		if self.object.data.paper_island_list:
self.unfolder.copy_island_names(self.object.data.paper_island_list)		self.unfolder.copy_island_names(self.object.data.paper_island_list)
self.unfolder.save(self.properties)		self.unfolder.save(self.properties)
self.report({'INFO'}, "Saved {}-page document".format(len(self.unfolder.mesh.pages)))		self.report({'INFO'}, "Saved a {}-page document".format(len(self.unfolder.mesh.pages)))
return {'FINISHED'}		return {'FINISHED'}
except UnfoldError as error:		except UnfoldError as error:
self.report(type={'ERROR_INVALID_INPUT'}, message=error.args[0])		self.report(type={'ERROR_INVALID_INPUT'}, message=error.args[0])
return {'CANCELLED'}		return {'CANCELLED'}
except:		except:
raise		raise
def get_scale_ratio(self, sce, margin=0):
if min(self.output_size_x, self.output_size_y) <= 2*self.output_margin:		def get_scale_ratio(self, sce):
		margin = self.output_margin + self.sticker_width + 1e-5
		if min(self.output_size_x, self.output_size_y) <= 2 * margin:
return False		return False
ratio = self.unfolder.mesh.largest_island_ratio(M.Vector((self.output_size_x-2margin, self.output_size_y-2margin)))		output_inner_size = M.Vector((self.output_size_x - 2margin, self.output_size_y - 2margin))
		ratio = self.unfolder.mesh.largest_island_ratio(output_inner_size)
return ratio * sce.unit_settings.scale_length / self.scale		return ratio * sce.unit_settings.scale_length / self.scale

def invoke(self, context, event):		def invoke(self, context, event):
sce=context.scene		sce = context.scene

self.scale = sce.paper_model.scale		self.scale = sce.paper_model.scale
self.object = context.active_object		self.object = context.active_object
self.unfolder = Unfolder(self.object)		self.unfolder = Unfolder(self.object)
self.unfolder.prepare(create_uvmap=self.do_create_uvmap, scale=sce.unit_settings.scale_length/self.scale)		self.unfolder.prepare(create_uvmap=self.do_create_uvmap, scale=sce.unit_settings.scale_length/self.scale)
scale_ratio = self.get_scale_ratio(sce, self.output_margin + self.sticker_width + 1e-5)		scale_ratio = self.get_scale_ratio(sce)
if scale_ratio > 1:		if scale_ratio > 1:
self.scale *= scale_ratio		self.scale *= scale_ratio
wm = context.window_manager		wm = context.window_manager
wm.fileselect_add(self)		wm.fileselect_add(self)
return {'RUNNING_MODAL'}		return {'RUNNING_MODAL'}

def draw(self, context):		def draw(self, context):
layout = self.layout		layout = self.layout
layout.prop(self.properties, "scale", text="Scale: 1") # a little hack: prints out, e.g., "Scale: 1: 72"		# a little hack: this prints out something like "Scale: 1: 72"
		layout.prop(self.properties, "scale", text="Scale: 1")
scale_ratio = self.get_scale_ratio(context.scene)		scale_ratio = self.get_scale_ratio(context.scene)
if scale_ratio > 1:		if scale_ratio > 1:
layout.label(text="An island is "+strf(scale_ratio)+"x bigger than page", icon="ERROR")		layout.label(text="An island is roughly {:.1f}x bigger than page".format(scale_ratio), icon="ERROR")
elif scale_ratio > 0:		elif scale_ratio > 0:
layout.label(text="Largest island is 1/"+strf(1/scale_ratio)+" of page")		layout.label(text="Largest island is roughly 1/{:.1f} of page".format(1 / scale_ratio))
layout.prop(self.properties, "do_create_uvmap")		layout.prop(self.properties, "do_create_uvmap")

box = layout.box()		box = layout.box()
row = box.row(align=True)		row = box.row(align=True)
row.prop(self.properties, "ui_expanded_document", text="", icon=('TRIA_DOWN' if self.ui_expanded_document else 'TRIA_RIGHT'), emboss=False)		row.prop(self.properties, "ui_expanded_document", text="",
		icon=('TRIA_DOWN' if self.ui_expanded_document else 'TRIA_RIGHT'), emboss=False)
row.label(text="Document Settings")		row.label(text="Document Settings")

if self.ui_expanded_document:		if self.ui_expanded_document:
box.prop(self.properties, "page_size_preset")		box.prop(self.properties, "page_size_preset")
col = box.column(align=True)		col = box.column(align=True)
col.active = self.page_size_preset == 'USER'		col.active = self.page_size_preset == 'USER'
col.prop(self.properties, "output_size_x")		col.prop(self.properties, "output_size_x")
col.prop(self.properties, "output_size_y")		col.prop(self.properties, "output_size_y")
Show All 12 Lines	if self.ui_expanded_document:
if len(self.object.data.uv_textures) == 8:		if len(self.object.data.uv_textures) == 8:
col.label(text="No UV slots left, No Texture is the only option.", icon='ERROR')		col.label(text="No UV slots left, No Texture is the only option.", icon='ERROR')
elif context.scene.render.engine != 'BLENDER_RENDER' and self.output_type != 'NONE':		elif context.scene.render.engine != 'BLENDER_RENDER' and self.output_type != 'NONE':
col.label(text="Blender Internal engine will be used for texture baking.", icon='ERROR')		col.label(text="Blender Internal engine will be used for texture baking.", icon='ERROR')
col.prop(self.properties, "image_packing", text="Images")		col.prop(self.properties, "image_packing", text="Images")

box = layout.box()		box = layout.box()
row = box.row(align=True)		row = box.row(align=True)
row.prop(self.properties, "ui_expanded_style", text="", icon=('TRIA_DOWN' if self.ui_expanded_style else 'TRIA_RIGHT'), emboss=False)		row.prop(self.properties, "ui_expanded_style", text="",
		icon=('TRIA_DOWN' if self.ui_expanded_style else 'TRIA_RIGHT'), emboss=False)
row.label(text="Colors and Style")		row.label(text="Colors and Style")

if self.ui_expanded_style:		if self.ui_expanded_style:
col = box.column()		col = box.column()
col.prop(self.style, "outer_color")		col.prop(self.style, "outer_color")
col.prop(self.style, "outer_width", text="Width (pixels)")		col.prop(self.style, "outer_width", text="Width (pixels)")
col.prop(self.style, "outer_style", text="Style")		col.prop(self.style, "outer_style", text="Style")
col = box.column()		col = box.column()
Show All 16 Lines	if self.ui_expanded_style:
col.prop(self.style, "use_inbg", text="Inner Lines Highlight:")		col.prop(self.style, "use_inbg", text="Inner Lines Highlight:")
sub = col.column()		sub = col.column()
sub.active = self.output_type != 'NONE' and self.style.use_inbg		sub.active = self.output_type != 'NONE' and self.style.use_inbg
sub.prop(self.style, "inbg_color", text="")		sub.prop(self.style, "inbg_color", text="")
sub.prop(self.style, "inbg_width", text="Relative width")		sub.prop(self.style, "inbg_width", text="Relative width")
col = box.column()		col = box.column()
col.active = self.do_create_stickers		col.active = self.do_create_stickers
col.prop(self.style, "sticker_fill")		col.prop(self.style, "sticker_fill")
col.prop(self.style, "sticker_color")
col.prop(self.style, "sticker_width", text="Outline width (pixels)")
box.prop(self.style, "text_color")		box.prop(self.style, "text_color")


def menu_func(self, context):		def menu_func(self, context):
self.layout.operator("export_mesh.paper_model", text="Paper Model (.svg)")		self.layout.operator("export_mesh.paper_model", text="Paper Model (.svg)")

class VIEW3D_PT_paper_model(bpy.types.Panel):
bl_label = "Paper Model"		class VIEW3D_PT_paper_model_tools(bpy.types.Panel):
		bl_label = "Tools"
bl_space_type = "VIEW_3D"		bl_space_type = "VIEW_3D"
bl_region_type = "TOOLS"		bl_region_type = "TOOLS"
		bl_category = "Paper Model"

def draw(self, context):		def draw(self, context):
layout = self.layout		layout = self.layout
sce = context.scene		sce = context.scene
obj = context.active_object		obj = context.active_object
mesh = obj.data if obj and obj.type == 'MESH' else None		mesh = obj.data if obj and obj.type == 'MESH' else None

layout.prop(sce.paper_model, "scale", text="Scale: 1")		layout.operator("export_mesh.paper_model")

box = layout.box()		col = layout.column(align=True)
box.prop(sce.paper_model, "limit_by_page")		col.label("Customization:")
if sce.paper_model.limit_by_page:		col.operator("mesh.unfold")
col = box.column(align=True)
col.prop(sce.paper_model, "output_size_x")		if context.mode == 'EDIT_MESH':
col.prop(sce.paper_model, "output_size_y")		row = layout.row(align=True)
		row.operator("mesh.mark_seam", text="Mark Seam").clear = False
		row.operator("mesh.mark_seam", text="Clear Seam").clear = True
		else:
		layout.operator("mesh.clear_all_seams")

		layout.prop(sce.paper_model, "scale", text="Model Scale: 1")

		col = layout.column(align=True)
		col.prop(sce.paper_model, "limit_by_page")
		sub = col.column(align=True)
		sub.active = sce.paper_model.limit_by_page
		sub.prop(sce.paper_model, "output_size_x")
		sub.prop(sce.paper_model, "output_size_y")


		class VIEW3D_PT_paper_model_islands(bpy.types.Panel):
		bl_label = "Islands"
		bl_space_type = "VIEW_3D"
		bl_region_type = "TOOLS"
		bl_category = "Paper Model"

		def draw(self, context):
		layout = self.layout
		sce = context.scene
		obj = context.active_object
		mesh = obj.data if obj and obj.type == 'MESH' else None

layout.operator("mesh.make_unfoldable")
box = layout.box()
if mesh and mesh.paper_island_list:		if mesh and mesh.paper_island_list:
box.label(text="1 island:" if len(mesh.paper_island_list) == 1 else "{} islands:".format(len(mesh.paper_island_list)))		layout.label(text="1 island:" if len(mesh.paper_island_list) == 1 else
box.template_list('UI_UL_list', 'paper_model_island_list', mesh, 'paper_island_list', mesh, 'paper_island_index', rows=1, maxrows=5)		"{} islands:".format(len(mesh.paper_island_list)))
# The first one is the identifier of the registered UIList to use (if you want only the default list,		layout.template_list('UI_UL_list', 'paper_model_island_list', mesh,
# with no custom draw code, use "UI_UL_list").		'paper_island_list', mesh, 'paper_island_index', rows=1, maxrows=5)
# layout.template_list("MATERIAL_UL_matslots_example", "", obj, "material_slots", obj, "active_material_index")
if mesh.paper_island_index >= 0:		if mesh.paper_island_index >= 0:
list_item = mesh.paper_island_list[mesh.paper_island_index]		list_item = mesh.paper_island_list[mesh.paper_island_index]
sub = box.column(align=True)		sub = layout.column(align=True)
sub.prop(list_item, "label")		sub.prop(list_item, "label")
sub.prop(list_item, "auto_abbrev")		sub.prop(list_item, "auto_abbrev")
row = sub.row()		row = sub.row()
row.active = not list_item.auto_abbrev		row.active = not list_item.auto_abbrev
row.prop(list_item, "abbreviation")		row.prop(list_item, "abbreviation")
#layout.prop(sce.paper_model, "display_labels", icon='RESTRICT_VIEW_OFF')
else:		else:
box.label(text="Not unfolded")		layout.label(text="Not unfolded")
sub = box.column(align=True)		layout.box().label("Use the 'Unfold' tool")
		sub = layout.column(align=True)
sub.active = bool(mesh and mesh.paper_island_list)		sub.active = bool(mesh and mesh.paper_island_list)
sub.prop(sce.paper_model, "display_islands", icon='RESTRICT_VIEW_OFF')		sub.prop(sce.paper_model, "display_islands", icon='RESTRICT_VIEW_OFF')
row = sub.row()		row = sub.row(align=True)
row.active = bool(sce.paper_model.display_islands and mesh and mesh.paper_island_list)		row.active = bool(sce.paper_model.display_islands and mesh and mesh.paper_island_list)
row.prop(sce.paper_model, "islands_alpha", slider=True)		row.prop(sce.paper_model, "islands_alpha", slider=True)

#sub = box.column(align=True)
#sub.active = bool(mesh.paper_island_list)
#sub.prop(sce.paper_model, "display_tabs", icon='RESTRICT_VIEW_OFF')
#sub.prop(sce.paper_model, "display_tabs_size")

layout.operator("export_mesh.paper_model")

def display_islands(self, context):		def display_islands(self, context):
#TODO: save the vertex positions and don't recalculate them always		# TODO: save the vertex positions and don't recalculate them always?
ob = context.active_object		ob = context.active_object
if not ob or ob.type != 'MESH':		if not ob or ob.type != 'MESH':
return		return
mesh = ob.data		mesh = ob.data
if not mesh.paper_island_list or mesh.paper_island_index == -1:		if not mesh.paper_island_list or mesh.paper_island_index == -1:
return		return

bgl.glMatrixMode(bgl.GL_PROJECTION)		bgl.glMatrixMode(bgl.GL_PROJECTION)
perspMatrix = context.space_data.region_3d.perspective_matrix		perspMatrix = context.space_data.region_3d.perspective_matrix
perspBuff = bgl.Buffer(bgl.GL_FLOAT, (4,4), perspMatrix.transposed())		perspBuff = bgl.Buffer(bgl.GL_FLOAT, (4, 4), perspMatrix.transposed())
bgl.glLoadMatrixf(perspBuff)		bgl.glLoadMatrixf(perspBuff)
bgl.glMatrixMode(bgl.GL_MODELVIEW)		bgl.glMatrixMode(bgl.GL_MODELVIEW)
objectBuff = bgl.Buffer(bgl.GL_FLOAT, (4,4), ob.matrix_world.transposed())		objectBuff = bgl.Buffer(bgl.GL_FLOAT, (4, 4), ob.matrix_world.transposed())
bgl.glLoadMatrixf(objectBuff)		bgl.glLoadMatrixf(objectBuff)
bgl.glEnable(bgl.GL_BLEND)		bgl.glEnable(bgl.GL_BLEND)
bgl.glBlendFunc(bgl.GL_SRC_ALPHA, bgl.GL_ONE_MINUS_SRC_ALPHA);		bgl.glBlendFunc(bgl.GL_SRC_ALPHA, bgl.GL_ONE_MINUS_SRC_ALPHA)
bgl.glEnable(bgl.GL_POLYGON_OFFSET_FILL)		bgl.glEnable(bgl.GL_POLYGON_OFFSET_FILL)
bgl.glPolygonOffset(0, -10) #offset in Zbuffer to remove flicker		bgl.glPolygonOffset(0, -10) # offset in Zbuffer to remove flicker
bgl.glPolygonMode(bgl.GL_FRONT_AND_BACK, bgl.GL_FILL)		bgl.glPolygonMode(bgl.GL_FRONT_AND_BACK, bgl.GL_FILL)
bgl.glColor4f(1.0, 0.4, 0.0, self.islands_alpha)		bgl.glColor4f(1.0, 0.4, 0.0, self.islands_alpha)
island = mesh.paper_island_list[mesh.paper_island_index]		island = mesh.paper_island_list[mesh.paper_island_index]
for lface in island.faces:		for lface in island.faces:
face = mesh.polygons[lface.id]		face = mesh.polygons[lface.id]
bgl.glBegin(bgl.GL_POLYGON)		bgl.glBegin(bgl.GL_POLYGON)
for vertex_id in face.vertices:		for vertex_id in face.vertices:
vertex = mesh.vertices[vertex_id]		vertex = mesh.vertices[vertex_id]
bgl.glVertex4f(*vertex.co.to_4d())		bgl.glVertex4f(*vertex.co.to_4d())
bgl.glEnd()		bgl.glEnd()
bgl.glPolygonOffset(0.0, 0.0)		bgl.glPolygonOffset(0.0, 0.0)
bgl.glDisable(bgl.GL_POLYGON_OFFSET_FILL)		bgl.glDisable(bgl.GL_POLYGON_OFFSET_FILL)
bgl.glLoadIdentity()		bgl.glLoadIdentity()
display_islands.handle = None		display_islands.handle = None


def display_islands_changed(self, context):		def display_islands_changed(self, context):
"""Switch highlighting islands on/off"""		"""Switch highlighting islands on/off"""
if self.display_islands:		if self.display_islands:
if not display_islands.handle:		if not display_islands.handle:
display_islands.handle = bpy.types.SpaceView3D.draw_handler_add(display_islands, (self, context), 'WINDOW', 'POST_VIEW')		display_islands.handle = bpy.types.SpaceView3D.draw_handler_add(display_islands, (self, context), 'WINDOW', 'POST_VIEW')
else:		else:
if display_islands.handle:		if display_islands.handle:
bpy.types.SpaceView3D.draw_handler_remove(display_islands.handle, 'WINDOW')		bpy.types.SpaceView3D.draw_handler_remove(display_islands.handle, 'WINDOW')
display_islands.handle = None		display_islands.handle = None


def label_changed(self, context):		def label_changed(self, context):
"""The labelling of an island was changed"""		"""The labelling of an island was changed"""
# access the properties via [..] to avoid a recursive call after the update		# accessing properties via [..] to avoid a recursive call after the update
if self.auto_abbrev:		if self.auto_abbrev:
self["abbreviation"] = "".join(first_letters(self.label)).upper()		self["abbreviation"] = "".join(first_letters(self.label)).upper()
elif len(self.abbreviation) > 3:		elif len(self.abbreviation) > 3:
self["abbreviation"] = self.abbreviation[:3]		self["abbreviation"] = self.abbreviation[:3]

self.name = "[{}] {} ({} {})".format(self.abbreviation, self.label, len(self.faces), "faces" if len(self.faces) > 1 else "face")		self.name = "[{}] {} ({} {})".format(self.abbreviation, self.label, len(self.faces), "faces" if len(self.faces) > 1 else "face")


class FaceList(bpy.types.PropertyGroup):		class FaceList(bpy.types.PropertyGroup):
id = bpy.props.IntProperty(name="Face ID")		id = bpy.props.IntProperty(name="Face ID")


class IslandList(bpy.types.PropertyGroup):		class IslandList(bpy.types.PropertyGroup):
faces = bpy.props.CollectionProperty(type=FaceList, name="Faces", description="Faces belonging to this island")		faces = bpy.props.CollectionProperty(type=FaceList, name="Faces",
label = bpy.props.StringProperty(name="Label", description="Label on this island", default="", update=label_changed)		description="Faces belonging to this island")
abbreviation = bpy.props.StringProperty(name="Abbreviation", description="Three-letter label to use when there is not enough space", default="", update=label_changed)		label = bpy.props.StringProperty(name="Label",
auto_abbrev = bpy.props.BoolProperty(name="Auto Abbreviation", description="Generate the abbreviation automatically", default=True, update=label_changed)		description="Label on this island",
		default="", update=label_changed)
		abbreviation = bpy.props.StringProperty(name="Abbreviation",
		description="Three-letter label to use when there is not enough space",
		default="", update=label_changed)
		auto_abbrev = bpy.props.BoolProperty(name="Auto Abbreviation",
		description="Generate the abbreviation automatically",
		default=True, update=label_changed)
bpy.utils.register_class(FaceList)		bpy.utils.register_class(FaceList)
bpy.utils.register_class(IslandList)		bpy.utils.register_class(IslandList)

#flip = bm.edges.layers.int.new("flip_tab")
#bmm.edges[0][bmm.edges.layers.int["flip_tab"]]

def display_tabs(self, context):
if context.active_object.type != 'MESH':
return
from bmesh import new as BMesh
bm = BMesh()
ob = context.active_object
bm.from_mesh(ob.data)
size = context.scene.paper_model.display_tabs_size

# remember the original value
polygonMode = bgl.Buffer(bgl.GL_INT, 2)
bgl.glGetIntegerv(bgl.GL_POLYGON_MODE, polygonMode)
try:
bgl.glMatrixMode(bgl.GL_PROJECTION)
perspMatrix = context.space_data.region_3d.perspective_matrix
perspBuff = bgl.Buffer(bgl.GL_FLOAT, (4,4), perspMatrix.transposed())
bgl.glLoadMatrixf(perspBuff)
bgl.glMatrixMode(bgl.GL_MODELVIEW)
bgl.glLoadIdentity()
#objectBuff = bgl.Buffer(bgl.GL_FLOAT, (4,4), ob.matrix_world.transposed())
#bgl.glLoadMatrixf(objectBuff)
bgl.glEnable(bgl.GL_POLYGON_OFFSET_LINE)
bgl.glPolygonOffset(0, -10) #offset in Zbuffer to remove flicker
bgl.glPolygonMode(bgl.GL_FRONT_AND_BACK, bgl.GL_LINE)
bgl.glColor3f(1.0, 0.2, 0.0)

matworld = ob.matrix_world
lin = matworld.to_3x3()
inv = lin.inverted()
invt = inv.transposed()

for edge in bm.edges:
# TODO: skip uncut edges whatsoever
for loop in edge.link_loops[1:]: # TODO: use custom edge layer to skip the correct one
face = loop.face
va, vb = loop.vert, loop.link_loop_next.vert

# TODO: decrease the size and increase the shear depending on the face's shape
shear = lin*(vb.co - va.co)
offset = -shear.cross(invt*face.normal)
shear = shear * size / shear.length
offset = offset * size / offset.length

bgl.glBegin(bgl.GL_POLYGON)
bgl.glVertex3f((matworldva.co))
bgl.glVertex3f((matworldvb.co))
bgl.glVertex3f((matworldvb.co + offset - shear))
bgl.glVertex3f((matworldva.co + offset + shear))
bgl.glEnd()

finally:
bgl.glPolygonOffset(0.0, 0.0)
bgl.glPolygonMode(bgl.GL_FRONT_AND_BACK, polygonMode[0])
del polygonMode
bgl.glDisable(bgl.GL_POLYGON_OFFSET_LINE)
bgl.glLoadIdentity()
display_tabs.handle = None

def display_tabs_changed(self, context):
if self.display_tabs:
if not display_tabs.handle:
display_tabs.handle = bpy.types.SpaceView3D.draw_handler_add(display_tabs, (self, context), 'WINDOW', 'POST_VIEW')
else:
if display_tabs.handle:
bpy.types.SpaceView3D.draw_handler_remove(display_tabs.handle, 'WINDOW')
display_tabs.handle = None

class PaperModelSettings(bpy.types.PropertyGroup):		class PaperModelSettings(bpy.types.PropertyGroup):
display_islands = bpy.props.BoolProperty(name="Highlight selected island", options={'SKIP_SAVE'}, update=display_islands_changed)		display_islands = bpy.props.BoolProperty(name="Highlight selected island",
islands_alpha = bpy.props.FloatProperty(name="Opacity", description="Opacity of island highlighting", min=0.0, max=1.0, default=0.3)		description="Highlight faces corresponding to the selected island in the 3D View",
display_tabs = bpy.props.BoolProperty(name="Display sticking tabs", options={'SKIP_SAVE'}, update=display_tabs_changed)		options={'SKIP_SAVE'}, update=display_islands_changed)
display_tabs_size = bpy.props.FloatProperty(name="Tab Size", description="Size of the sticker tabs in the 3D View", min=0.0, soft_max=0.2, default=0.05, unit='LENGTH')		islands_alpha = bpy.props.FloatProperty(name="Opacity",
limit_by_page = bpy.props.BoolProperty(name="Limit Island Size", description="Limit island size by page dimensions")		description="Opacity of island highlighting", min=0.0, max=1.0, default=0.3)
output_size_x = bpy.props.FloatProperty(name="Page Width", description="Maximal width of an island", default=0.210, soft_min=0.105, soft_max=0.841, subtype="UNSIGNED", unit="LENGTH")		limit_by_page = bpy.props.BoolProperty(name="Limit Island Size",
output_size_y = bpy.props.FloatProperty(name="Page Height", description="Maximal height of an island", default=0.297, soft_min=0.148, soft_max=1.189, subtype="UNSIGNED", unit="LENGTH")		description="Do not create islands larger than given dimensions", default=False)
scale = bpy.props.FloatProperty(name="Scale", description="Divisor of all dimensions when exporting", default=1, soft_min=1.0, soft_max=10000.0, subtype='UNSIGNED', precision=0)		output_size_x = bpy.props.FloatProperty(name="Width",
		description="Maximal width of an island",
		default=0.2, soft_min=0.105, soft_max=0.841, subtype="UNSIGNED", unit="LENGTH")
		output_size_y = bpy.props.FloatProperty(name="Height",
		description="Maximal height of an island",
		default=0.29, soft_min=0.148, soft_max=1.189, subtype="UNSIGNED", unit="LENGTH")
		scale = bpy.props.FloatProperty(name="Scale",
		description="Divisor of all dimensions when exporting",
		default=1, soft_min=1.0, soft_max=10000.0, subtype='UNSIGNED', precision=0)
		do_ignore_errors = bpy.props.BoolProperty(name="Ignore Errors",
		description="In case of geometry errors, take a less cautious approach. May produce incorrect output", default=False)
bpy.utils.register_class(PaperModelSettings)		bpy.utils.register_class(PaperModelSettings)


def register():		def register():
bpy.utils.register_module(__name__)		bpy.utils.register_module(__name__)

bpy.types.Scene.paper_model = bpy.props.PointerProperty(type=PaperModelSettings, name="Paper Model", description="Settings of the Export Paper Model script", options={'SKIP_SAVE'})		bpy.types.Scene.paper_model = bpy.props.PointerProperty(type=PaperModelSettings,
bpy.types.Mesh.paper_island_list = bpy.props.CollectionProperty(type=IslandList, name= "Island List", description= "")		name="Paper Model",
bpy.types.Mesh.paper_island_index = bpy.props.IntProperty(name="Island List Index", default= -1, min= -1, max= 100, options={'SKIP_SAVE'})		description="Settings of the Export Paper Model script",
		options={'SKIP_SAVE'})
		bpy.types.Mesh.paper_island_list = bpy.props.CollectionProperty(type=IslandList,
		name="Island List", description="")
		bpy.types.Mesh.paper_island_index = bpy.props.IntProperty(name="Island List Index",
		default=-1, min=-1, max=100, options={'SKIP_SAVE'})
bpy.types.INFO_MT_file_export.append(menu_func)		bpy.types.INFO_MT_file_export.append(menu_func)


def unregister():		def unregister():
bpy.utils.unregister_module(__name__)		bpy.utils.unregister_module(__name__)
bpy.types.INFO_MT_file_export.remove(menu_func)		bpy.types.INFO_MT_file_export.remove(menu_func)
if display_islands.handle:		if display_islands.handle:
bpy.types.SpaceView3D.draw_handler_remove(display_islands.handle, 'WINDOW')		bpy.types.SpaceView3D.draw_handler_remove(display_islands.handle, 'WINDOW')
display_islands.handle = None		display_islands.handle = None
if display_tabs.handle:
bpy.types.SpaceView3D.draw_handler_remove(display_tabs.handle, 'WINDOW')
display_tabs.handle = None

if __name__ == "__main__":		if __name__ == "__main__":
register()		register()