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sent triangulate from polyhedron.py to polygon.py

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Pilar 2021-03-30 15:12:54 -04:00
parent e353a7c800
commit 17ff59827e
2 changed files with 255 additions and 255 deletions
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254
city_model_structure/attributes/polygon.py
View File

@ -155,3 +155,257 @@ class Polygon:
return alpha
else:
return -alpha
def triangulate(self):
"""
triangulates a polygon following the ear clipping methodology
:return: list[triangles]
"""
points_list = self.points_list
normal = self.normal
# are points concave or convex?
total_points_list, concave_points, convex_points = self._starting_lists(points_list, normal)
# list of ears
ears = []
while len(concave_points) > 3 or len(convex_points) != 0:
for i in range(0, len(concave_points)):
ear = self._triangle(points_list, total_points_list, concave_points[i])
rest_points = []
for p in total_points_list:
rest_points.append(list(self.points[p]))
if self._is_ear(ear, rest_points):
ears.append(ear)
point_to_remove = concave_points[i]
previous_point_in_list, next_point_in_list = self._enveloping_points(point_to_remove, total_points_list)
total_points_list.remove(point_to_remove)
concave_points.remove(point_to_remove)
# Was any of the adjacent points convex? -> check if changed status to concave
# for j in range(0, len(convex_points)):
for convex_point in convex_points:
if convex_point == previous_point_in_list:
concave_points, convex_points, end_loop = self._if_concave_change_status(normal, points_list,
convex_point, total_points_list,
concave_points, convex_points,
previous_point_in_list)
if end_loop:
break
continue
if convex_point == next_point_in_list:
concave_points, convex_points, end_loop = self._if_concave_change_status(normal, points_list,
convex_point, total_points_list,
concave_points, convex_points,
next_point_in_list)
if end_loop:
break
continue
break
if len(total_points_list) <= 3 and len(convex_points) > 0:
sys.stderr.write(f'Not able to triangulate polygon\n')
return [self]
last_ear = self._triangle(points_list, total_points_list, concave_points[1])
ears.append(last_ear)
return ears
@staticmethod
def _starting_lists(points_list, normal):
"""
creates the list of vertices (points) that define the polygon (total_points_list), together with other two lists
separating points between convex and concave
:param points_list: points_list
:param normal: normal
:return: list[point], list[point], list[point]
"""
concave_points = []
convex_points = []
# lists of concave and convex points
# case 1: first point
point = points_list[0:3]
previous_point = points_list[len(points_list) - 3:]
next_point = points_list[3:6]
index = 0
total_points_list = [index]
if Polygon._point_is_concave(normal, point, previous_point, next_point):
concave_points.append(index)
else:
convex_points.append(index)
# case 2: all points except first and last
for i in range(0, int((len(points_list)-6)/3)):
point = points_list[(i+1)*3:(i+2)*3]
previous_point = points_list[i*3:(i+1)*3]
next_point = points_list[(i+2)*3:(i+3)*3]
index = i+1
total_points_list.append(index)
if Polygon._point_is_concave(normal, point, previous_point, next_point):
concave_points.append(index)
else:
convex_points.append(index)
# case 3: last point
point = points_list[len(points_list) - 3:]
previous_point = points_list[len(points_list) - 6:len(points_list) - 3]
next_point = points_list[0:3]
index = int(len(points_list)/3) - 1
total_points_list.append(index)
if Polygon._point_is_concave(normal, point, previous_point, next_point):
concave_points.append(index)
else:
convex_points.append(index)
return total_points_list, concave_points, convex_points
@staticmethod
def _triangle(points_list, total_points_list, point_position):
"""
creates a triangular polygon out of three points
:param points_list: points_list
:param total_points_list: [point]
:param point_position: int
:return: polygon
"""
index = point_position * 3
previous_point_index, next_point_index = Polygon._enveloping_points_indices(point_position, total_points_list)
points = points_list[previous_point_index:previous_point_index + 3]
points = np.append(points, points_list[index:index + 3])
points = np.append(points, points_list[next_point_index:next_point_index + 3])
points = gh.to_points_matrix(points)
triangle = Polygon(points)
return triangle
@staticmethod
def _enveloping_points_indices(point_position, total_points_list):
"""
due to the fact that the lists are not circular, a method to find the previous and next points
of an specific one is needed
:param point_position: int
:param total_points_list: [point]
:return: int, int
"""
previous_point_index = None
next_point_index = None
if point_position == total_points_list[0]:
previous_point_index = total_points_list[len(total_points_list) - 1] * 3
next_point_index = total_points_list[1] * 3
if point_position == total_points_list[len(total_points_list) - 1]:
previous_point_index = total_points_list[len(total_points_list) - 2] * 3
next_point_index = total_points_list[0] * 3
for i in range(1, len(total_points_list)-1):
if point_position == total_points_list[i]:
previous_point_index = total_points_list[i - 1] * 3
next_point_index = total_points_list[i + 1] * 3
return previous_point_index, next_point_index
@staticmethod
def _enveloping_points(point_to_remove, total_points_list):
"""
due to the fact that the lists are not circular, a method to find the previous and next points
of an specific one is needed
:param point_to_remove: point
:param total_points_list: [point]
:return: point, point
"""
index = total_points_list.index(point_to_remove)
if index == 0:
previous_point_in_list = total_points_list[len(total_points_list) - 1]
next_point_in_list = total_points_list[1]
elif index == len(total_points_list) - 1:
previous_point_in_list = total_points_list[len(total_points_list) - 2]
next_point_in_list = total_points_list[0]
else:
previous_point_in_list = total_points_list[index - 1]
next_point_in_list = total_points_list[index + 1]
return previous_point_in_list, next_point_in_list
@staticmethod
def _is_ear(ear, points) -> bool:
"""
finds whether a triangle is an ear of the polygon
:param ear: polygon
:param points: [point]
:return: boolean
"""
area_ear = ear.area
for point in points:
area_points = 0
point_is_not_vertex = True
for i in range(0, 3):
if abs(np.linalg.norm(point) - np.linalg.norm(ear.points[i])) < 0.0001:
point_is_not_vertex = False
break
if point_is_not_vertex:
for i in range(0, 3):
if i != 2:
new_points = ear.points[i][:]
new_points = np.append(new_points, ear.points[i + 1][:])
new_points = np.append(new_points, point[:])
else:
new_points = ear.points[i][:]
new_points = np.append(new_points, point[:])
new_points = np.append(new_points, ear.points[0][:])
new_points = gh.to_points_matrix(new_points)
new_triangle = Polygon(new_points)
area_points += new_triangle.area
if abs(area_points - area_ear) < 1e-6:
# point_inside_ear = True
return False
return True
@staticmethod
def _if_concave_change_status(normal, points_list, convex_point, total_points_list,
concave_points, convex_points, point_in_list):
"""
checks whether an convex specific point change its status to concave after removing one ear in the polygon
returning the new convex and concave points lists together with a flag advising that the list of total points
already 3 and, therefore, the triangulation must be finished.
:param normal: normal
:param points_list: points_list
:param convex_point: int
:param total_points_list: [point]
:param concave_points: [point]
:param convex_points: [point]
:param point_in_list: int
:return: list[points], list[points], boolean
"""
end_loop = False
point = points_list[point_in_list * 3:(point_in_list + 1) * 3]
pointer = total_points_list.index(point_in_list) - 1
if pointer < 0:
pointer = len(total_points_list) - 1
previous_point = points_list[total_points_list[pointer] * 3:total_points_list[pointer] * 3 + 3]
pointer = total_points_list.index(point_in_list) + 1
if pointer >= len(total_points_list):
pointer = 0
next_point = points_list[total_points_list[pointer] * 3:total_points_list[pointer] * 3 + 3]
if Polygon._point_is_concave(normal, point, previous_point, next_point):
if concave_points[0] > convex_point:
concave_points.insert(0, convex_point)
elif concave_points[len(concave_points) - 1] < convex_point:
concave_points.append(convex_point)
else:
for p in range(0, len(concave_points) - 1):
if concave_points[p] < convex_point < concave_points[p + 1]:
concave_points.insert(p + 1, convex_point)
convex_points.remove(convex_point)
end_loop = True
return concave_points, convex_points, end_loop
@staticmethod
def _point_is_concave(normal, point, previous_point, next_point) -> bool:
"""
returns whether a point is concave
:param normal: normal
:param point: point
:param previous_point: point
:param next_point: point
:return: boolean
"""
is_concave = False
accepted_error = 0.1
points = np.append(previous_point, point)
points = np.append(points, next_point)
points = gh.to_points_matrix(points)
triangle = Polygon(points)
error_sum = 0
for i in range(0, len(normal)):
error_sum += triangle.normal[i] - normal[i]
if np.abs(error_sum) < accepted_error:
is_concave = True
return is_concave

256
city_model_structure/attributes/polyhedron.py
View File

@ -4,13 +4,11 @@ SPDX - License - Identifier: LGPL - 3.0 - or -later
Copyright © 2020 Project Author Guille Gutierrez guillermo.gutierrezmorote@concordia.ca
Contributors Pilar Monsalvete pilar_monsalvete@yahoo.es
"""
import sys
import numpy as np
from trimesh import Trimesh
from helpers.geometry_helper import GeometryHelper
from helpers.configuration_helper import ConfigurationHelper
from city_model_structure.attributes.polygon import Polygon
from helpers.geometry_helper import GeometryHelper as gh
class Polyhedron:
@ -64,258 +62,6 @@ class Polyhedron:
self._vertices = np.asarray(self._vertices)
return self._vertices
def _triangulate(self, polygon) -> [Polygon]:
"""
triangulates a polygon following the ear clipping methodology
:param polygon: polygon
:return: list[triangles]
"""
points_list = polygon.points_list
normal = polygon.normal
# are points concave or convex?
total_points_list, concave_points, convex_points = self._starting_lists(points_list, normal)
# list of ears
ears = []
while len(concave_points) > 3 or len(convex_points) != 0:
for i in range(0, len(concave_points)):
ear = self._triangle(points_list, total_points_list, concave_points[i])
rest_points = []
for p in total_points_list:
rest_points.append(list(polygon.points[p]))
if self._is_ear(ear, rest_points):
ears.append(ear)
point_to_remove = concave_points[i]
previous_point_in_list, next_point_in_list = self._enveloping_points(point_to_remove, total_points_list)
total_points_list.remove(point_to_remove)
concave_points.remove(point_to_remove)
# Was any of the adjacent points convex? -> check if changed status to concave
# for j in range(0, len(convex_points)):
for convex_point in convex_points:
if convex_point == previous_point_in_list:
concave_points, convex_points, end_loop = self._if_concave_change_status(normal, points_list,
convex_point, total_points_list,
concave_points, convex_points,
previous_point_in_list)
if end_loop:
break
continue
if convex_point == next_point_in_list:
concave_points, convex_points, end_loop = self._if_concave_change_status(normal, points_list,
convex_point, total_points_list,
concave_points, convex_points,
next_point_in_list)
if end_loop:
break
continue
break
if len(total_points_list) <= 3 and len(convex_points) > 0:
sys.stderr.write(f'Not able to triangulate polygon\n')
return [polygon]
last_ear = self._triangle(points_list, total_points_list, concave_points[1])
ears.append(last_ear)
return ears
def _if_concave_change_status(self, normal, points_list, convex_point, total_points_list,
concave_points, convex_points, point_in_list):
"""
checks whether an convex specific point change its status to concave after removing one ear in the polygon
returning the new convex and concave points lists together with a flag advising that the list of total points
already 3 and, therefore, the triangulation must be finished.
:param normal: normal
:param points_list: points_list
:param convex_point: int
:param total_points_list: [point]
:param concave_points: [point]
:param convex_points: [point]
:param point_in_list: int
:return: list[points], list[points], boolean
"""
end_loop = False
point = points_list[point_in_list * 3:(point_in_list + 1) * 3]
pointer = total_points_list.index(point_in_list) - 1
if pointer < 0:
pointer = len(total_points_list) - 1
previous_point = points_list[total_points_list[pointer] * 3:total_points_list[pointer] * 3 + 3]
pointer = total_points_list.index(point_in_list) + 1
if pointer >= len(total_points_list):
pointer = 0
next_point = points_list[total_points_list[pointer] * 3:total_points_list[pointer] * 3 + 3]
if self._point_is_concave(normal, point, previous_point, next_point):
if concave_points[0] > convex_point:
concave_points.insert(0, convex_point)
elif concave_points[len(concave_points) - 1] < convex_point:
concave_points.append(convex_point)
else:
for p in range(0, len(concave_points) - 1):
if concave_points[p] < convex_point < concave_points[p + 1]:
concave_points.insert(p + 1, convex_point)
convex_points.remove(convex_point)
end_loop = True
return concave_points, convex_points, end_loop
def _starting_lists(self, points_list, normal):
"""
creates the list of vertices (points) that define the polygon (total_points_list), together with other two lists
separating points between convex and concave
:param points_list: points_list
:param normal: normal
:return: list[point], list[point], list[point]
"""
concave_points = []
convex_points = []
# lists of concave and convex points
# case 1: first point
point = points_list[0:3]
previous_point = points_list[len(points_list) - 3:]
next_point = points_list[3:6]
index = 0
total_points_list = [index]
if self._point_is_concave(normal, point, previous_point, next_point):
concave_points.append(index)
else:
convex_points.append(index)
# case 2: all points except first and last
for i in range(0, int((len(points_list)-6)/3)):
point = points_list[(i+1)*3:(i+2)*3]
previous_point = points_list[i*3:(i+1)*3]
next_point = points_list[(i+2)*3:(i+3)*3]
index = i+1
total_points_list.append(index)
if self._point_is_concave(normal, point, previous_point, next_point):
concave_points.append(index)
else:
convex_points.append(index)
# case 3: last point
point = points_list[len(points_list) - 3:]
previous_point = points_list[len(points_list) - 6:len(points_list) - 3]
next_point = points_list[0:3]
index = int(len(points_list)/3) - 1
total_points_list.append(index)
if self._point_is_concave(normal, point, previous_point, next_point):
concave_points.append(index)
else:
convex_points.append(index)
return total_points_list, concave_points, convex_points
@staticmethod
def _point_is_concave(normal, point, previous_point, next_point) -> bool:
"""
returns whether a point is concave
:param normal: normal
:param point: point
:param previous_point: point
:param next_point: point
:return: boolean
"""
is_concave = False
accepted_error = 0.1
points = np.append(previous_point, point)
points = np.append(points, next_point)
points = gh.to_points_matrix(points)
triangle = Polygon(points)
error_sum = 0
for i in range(0, len(normal)):
error_sum += triangle.normal[i] - normal[i]
if np.abs(error_sum) < accepted_error:
is_concave = True
return is_concave
def _triangle(self, points_list, total_points_list, point_position) -> Polygon:
"""
creates a triangular polygon out of three points
:param points_list: points_list
:param total_points_list: [point]
:param point_position: int
:return: polygon
"""
index = point_position * 3
previous_point_index, next_point_index = self._enveloping_points_indices(point_position, total_points_list)
points = points_list[previous_point_index:previous_point_index + 3]
points = np.append(points, points_list[index:index + 3])
points = np.append(points, points_list[next_point_index:next_point_index + 3])
points = gh.to_points_matrix(points)
triangle = Polygon(points)
return triangle
@staticmethod
def _enveloping_points_indices(point_position, total_points_list):
"""
due to the fact that the lists are not circular, a method to find the previous and next points
of an specific one is needed
:param point_position: int
:param total_points_list: [point]
:return: int, int
"""
previous_point_index = None
next_point_index = None
if point_position == total_points_list[0]:
previous_point_index = total_points_list[len(total_points_list) - 1] * 3
next_point_index = total_points_list[1] * 3
if point_position == total_points_list[len(total_points_list) - 1]:
previous_point_index = total_points_list[len(total_points_list) - 2] * 3
next_point_index = total_points_list[0] * 3
for i in range(1, len(total_points_list)-1):
if point_position == total_points_list[i]:
previous_point_index = total_points_list[i - 1] * 3
next_point_index = total_points_list[i + 1] * 3
return previous_point_index, next_point_index
@staticmethod
def _enveloping_points(point_to_remove, total_points_list):
"""
due to the fact that the lists are not circular, a method to find the previous and next points
of an specific one is needed
:param point_to_remove: point
:param total_points_list: [point]
:return: point, point
"""
index = total_points_list.index(point_to_remove)
if index == 0:
previous_point_in_list = total_points_list[len(total_points_list) - 1]
next_point_in_list = total_points_list[1]
elif index == len(total_points_list) - 1:
previous_point_in_list = total_points_list[len(total_points_list) - 2]
next_point_in_list = total_points_list[0]
else:
previous_point_in_list = total_points_list[index - 1]
next_point_in_list = total_points_list[index + 1]
return previous_point_in_list, next_point_in_list
@staticmethod
def _is_ear(ear, points) -> bool:
"""
finds whether a triangle is an ear of the polygon
:param ear: polygon
:param points: [point]
:return: boolean
"""
area_ear = ear.area
for point in points:
area_points = 0
point_is_not_vertex = True
for i in range(0, 3):
if abs(np.linalg.norm(point) - np.linalg.norm(ear.points[i])) < 0.0001:
point_is_not_vertex = False
break
if point_is_not_vertex:
for i in range(0, 3):
if i != 2:
new_points = ear.points[i][:]
new_points = np.append(new_points, ear.points[i + 1][:])
new_points = np.append(new_points, point[:])
else:
new_points = ear.points[i][:]
new_points = np.append(new_points, point[:])
new_points = np.append(new_points, ear.points[0][:])
new_points = gh.to_points_matrix(new_points)
new_triangle = Polygon(new_points)
area_points += new_triangle.area
if abs(area_points - area_ear) < 1e-6:
# point_inside_ear = True
return False
return True
@property
def faces(self) -> [[int]]:
@ -332,7 +78,7 @@ class Polyhedron:
face = []
points = polygon.points
if len(points) != 3:
sub_polygons = self._triangulate(polygon)
sub_polygons = polygon.triangulate()
# todo: I modified this! To be checked @Guille
if len(sub_polygons) >= 1:
for sub_polygon in sub_polygons: