def __init__(self, bbox, db):
self.bbox = bbox
height, width = bbox.spheric_sizes()
# Compute number of squares, assumming a size of 500 meters
# per square
self.width_square_count = width / 500
self.height_square_count = height / 500
# Compute the size in angles of the squares
self.width_square_angle = abs(bbox.get_top_left()[1] - bbox.get_bottom_right()[1]) / self.width_square_count
self.height_square_angle = abs(bbox.get_top_left()[0] - bbox.get_bottom_right()[0]) / self.height_square_count
# Compute the lists of longitudes and latitudes of the
# horizontal and vertical lines delimiting the square
self.vertical_lines = [
bbox.get_top_left()[1] + x * self.width_square_angle
for x in xrange(0, int(math.floor(self.width_square_count)) + 1)
]
self.horizontal_lines = [
bbox.get_top_left()[0] - x * self.height_square_angle
for x in xrange(0, int(math.floor(self.height_square_count)) + 1)
]
# Compute the lists of labels
self.vertical_labels = [
utils.gen_vertical_square_label(x) for x in xrange(0, int(math.ceil(self.width_square_count)))
]
self.horizontal_labels = [
utils.gen_horizontal_square_label(x) for x in xrange(0, int(math.ceil(self.height_square_count)))
]
l.debug("vertical lines: %s" % self.vertical_lines)
l.debug("horizontal lines: %s" % self.horizontal_lines)
l.debug("vertical labels: %s" % self.vertical_labels)
l.debug("horizontal labels: %s" % self.horizontal_labels)
def _user_readable_label(squares):
"""Creates a label usable in the street index adjacent to the map
from a square list."""
def couple_compare(x,y):
a = y[0] - x[0]
if a:
return a
return y[1] - x[1]
def distance(a,b):
return (b[0]-a[0])**2 + (b[1]-a[1])**2
minx = min([x[0] for x in squares])
maxx = max([x[0] for x in squares])
miny = min([x[1] for x in squares])
maxy = max([x[1] for x in squares])
if len(squares) == 1:
label = (utils.gen_vertical_square_label(squares[0][0]) +
utils.gen_horizontal_square_label(squares[0][1]))
elif minx == maxx:
label = ('%s%s-%s' % (utils.gen_vertical_square_label(minx),
utils.gen_horizontal_square_label(miny),
utils.gen_horizontal_square_label(maxy)))
elif miny == maxy:
label = ('%s-%s%s' % (utils.gen_vertical_square_label(minx),
utils.gen_vertical_square_label(maxx),
utils.gen_horizontal_square_label(miny)))
elif (maxx - minx + 1) * (maxy - miny + 1) == len(squares):
label = ('%s-%s%s-%s' % (utils.gen_vertical_square_label(minx),
utils.gen_vertical_square_label(maxx),
utils.gen_horizontal_square_label(miny),
utils.gen_horizontal_square_label(maxy)))
else:
squares_x_first = sorted(squares, couple_compare)
squares_y_first = sorted(squares, lambda x,y: couple_compare(y,x))
if (distance(squares_x_first[0], squares_x_first[-1]) >
distance(squares_y_first[0], squares_y_first[-1])):
first = squares_x_first[0]
last = squares_x_first[-1]
else:
first = squares_y_first[0]
last = squares_y_first[-1]
label = '%s%s...%s%s' % (utils.gen_vertical_square_label(first[0]),
utils.gen_horizontal_square_label(first[1]),
utils.gen_vertical_square_label(last[0]),
utils.gen_horizontal_square_label(last[1]))
return label
