def brute_sweep_intersections(segments):
start = time()
counter = 0
status = {
"upper": 0,
"lower": 1,
}
points = []
event_queue = Tree(event_lt)
status_queue = {}
for segment in segments:
event_queue.insert(upper_end(*segment), (status["upper"], segment))
event_queue.insert(lower_end(*segment), (status["lower"], segment))
while not event_queue.empty():
(_, (label, segment)) = event_queue.pop()
if label == status["upper"]:
for other in list(status_queue.keys()):
counter += 1
point = point_of_intersection(segment, other)
if point is not None:
points.append(point)
status_queue[segment] = None
else:
del status_queue[segment]
print(results(True, counter, not len(points) == len(set(points)), start))
return (segments, points)
def sweep_intersections(segments):
start = time()
counter = 0
status = {
"upper": 0,
"intersection": 1,
"lower": 2,
}
points = []
memo = {}
event_queue = Tree(event_lt)
status_queue = Tree(status_lt)
for segment in segments:
event_queue.insert(upper_end(*segment), (status["upper"], segment))
event_queue.insert(lower_end(*segment), (status["lower"], segment))
while not event_queue.empty():
(event, (label, payload)) = event_queue.pop()
(_, y) = event
if label == status["upper"]:
memo[payload] = event
status_queue.insert((event, payload), None)
(left, right) = status_queue.neighbors((event, payload))
if left is not None:
((_, left_segment), _) = left
counter += 1
update_points(
event_queue,
y,
left_segment,
payload,
status["intersection"],
)
if right is not None:
((_, right_segment), _) = right
counter += 1
update_points(
event_queue,
y,
payload,
right_segment,
status["intersection"],
)
elif label == status["lower"]:
(left, right) = status_queue.neighbors((memo[payload], payload))
status_queue.delete((memo[payload], payload))
if (left is not None) and (right is not None):
((_, left_segment), _) = left
((_, right_segment), _) = right
counter += 1
update_points(
event_queue,
y,
left_segment,
right_segment,
status["intersection"],
)
else:
points.append(event)
(right, left) = payload
status_queue.delete((memo[left], left))
status_queue.delete((memo[right], right))
memo[left] = event
memo[right] = event
status_queue.insert((memo[left], left), None)
status_queue.insert((memo[right], right), None)
(far_left, _) = status_queue.neighbors((memo[left], left))
(_, far_right) = status_queue.neighbors((memo[right], right))
if far_left is not None:
((_, far_left_segment), _) = far_left
counter += 1
update_points(
event_queue,
y,
far_left_segment,
left,
status["intersection"],
)
if far_right is not None:
((_, far_right_segment), _) = far_right
counter += 1
update_points(
event_queue,
y,
right,
far_right_segment,
status["intersection"],
)
print(results(False, counter, not len(points) == len(set(points)), start))
return (segments, points)
