def build_intersections(self):
for street_name in self.streets.keys():
for adjacent_street_name in self.adjacent_street_names[
street_name]:
current_street = self.streets[street_name]
adjacent_street = self.streets[adjacent_street_name]
current_street_heading = current_street.road_component_list[
len(current_street.road_component_list) - 1].heading
adjacent_street_heading = adjacent_street.road_component_list[
0].heading
end_point_incoming_street = current_street.road_component_list[
len(current_street.road_component_list) - 1].end_point
start_point_outgoing_street = adjacent_street.road_component_list[
0].start_point
# Always take the last road component
if current_street_heading == adjacent_street_heading:
# Current street and adjacent street have the same heading. Intersection will have only one
# road component; it starts where the incoming street ends, and ends where the outgoing street
# starts.
intersection_road_component = RoadComponent(
heading=adjacent_street.road_component_list[0].heading,
start=end_point_incoming_street,
end=start_point_outgoing_street)
intersection = Intersection()
intersection.add_road_component(
intersection_road_component)
# Place the intersection in the intersection dictionary
if street_name not in self.corresponding_intersections:
self.corresponding_intersections[street_name] = dict()
self.corresponding_intersections[street_name][
adjacent_street_name] = intersection
else:
# Streets have different heading, meaning 2 road components (90 degree turn)
intersection = Intersection()
intersection_first_line_start = end_point_incoming_street
if current_street_heading in (MapHeading.NORTH,
MapHeading.SOUTH):
intersection_first_line_end = MapPoint(
x=start_point_outgoing_street.x,
y=end_point_incoming_street.y)
else:
intersection_first_line_end = MapPoint(
x=end_point_incoming_street.x,
y=start_point_outgoing_street.y)
intersection_first_road_component = RoadComponent(
heading=current_street_heading,
start=intersection_first_line_start,
end=intersection_first_line_end)
intersection.add_road_component(
intersection_first_road_component)
intersection_second_line_start = intersection_first_line_end
intersection_second_line_end = start_point_outgoing_street
intersection_second_road_component = RoadComponent(
heading=adjacent_street_heading,
start=intersection_second_line_start,
end=intersection_second_line_end)
intersection.add_road_component(
intersection_second_road_component)
if street_name not in self.corresponding_intersections:
self.corresponding_intersections[street_name] = dict()
self.corresponding_intersections[street_name][
adjacent_street_name] = intersection
