def execute(delta, theta, center, max_connection_dist, contours, lines):
# rotate contours in the opposite direction, so that we
# process lines that are aligned with x and y axes
neg_rot_contours = []
for contour in contours:
neg_rot_contours.append(rotate_xy(contour, -theta, center))
lines = pcu.clip_lines(lines, neg_rot_contours)
lines = _connect_lines(lines, delta, theta, center, max_connection_dist)
return lines
def _connect_lines(lines, delta, theta, center, max_connection_dist):
# lines are np arrays of np arrays tha represent vertices
connected_lines = []
# lines should be aligned left-right and be parallel to X-axis
lines_by_y = {}
d_lines = []
for line in lines:
# align left to right
if line[0][0] > line[-1][0]:
line = line[::-1]
# line should be a list of np arrays that represent vertices
line = list(line)
d_lines.append(line)
lines_by_y.setdefault(line[0][1], []).append(line)
y_positions = sorted(lines_by_y.keys())
dist_squared = max_connection_dist ** 2
while len(lines_by_y) > 0:
prev_y = y_positions[0]
# line has to be a list, not a np array
# because points will be added to it
line = lines_by_y[prev_y].pop()
# used y-positions to be removed from line collections
used_ys = [prev_y]
for y in y_positions[1:]:
if not prev_y < y < prev_y + (2 * delta): # > prev_y and np.isclose(y, prev_y + delta):
break
# find if any of lines at the next y is close enough to connect
next_line_connection_side = 0 if ((len(line) % 4) is 0) else -1
current_line_connection_vertex = line[-1]
for line_idx, l in enumerate(lines_by_y[y]):
next_line_vertex = l[next_line_connection_side]
# TODO: maybe do a clip in the square between points and if resulting number of polygons
# is 1 than we cont need the euclidean dist -> just put that polygon into line
if euclidean_dist_square(current_line_connection_vertex, next_line_vertex) < dist_squared:
del lines_by_y[y][line_idx]
used_ys.append(y)
# properly orient the line
if next_line_connection_side is -1:
l = l[::-1]
line.extend(list(l))
# go for next y position
break
prev_y = y
for y in used_ys:
if len(lines_by_y[y]) is 0:
del lines_by_y[y]
y_positions.remove(y)
# convert back to np array
connected_lines.append(rotate_xy(to_ndarray(line), theta, center))
return connected_lines