def decode(big_str, coords, base, m):
"""Decodes big number back to delta coordinates
Args:
big_str: Big string encoding as returned by heuristic.big_encode
coords: Delta coordinates of the original polygon used for created big string
base
Returns:
True if the decoded list of delta coordinates matches original delta coordinates `coords`.
False otherwise.
"""
for i in [1,2]:
M = helpers.base_decode(big_str[:i], base)
M = M + 2
big_num = helpers.base_decode(big_str[i:], base)
z = big_num/const.y_factor
Dy_min = big_num - const.y_factor * z
big_num = z
z = big_num/const.x_factor
Dx_min = big_num - const.x_factor * z
big_num = z
deltas = []
flagged = False
while big_num > 0:
m = big_num % M
big_num = big_num / M
deltas.append(int(m))
deltas = deltas[::-1]
deltas[0] -= 1
deltas[1] -= 1
if deltas == coords:
return True
def decode(big_str, coords, base, m):
"""Decodes big number back to delta coordinates
Args:
big_str: Big string encoding as returned by heuristic.big_encode
coords: Delta coordinates of the original polygon used for created big string
base
Returns:
True if the decoded list of delta coordinates matches original delta coordinates `coords`.
False otherwise.
"""
for i in [1,2]:
M = helpers.base_decode(big_str[:i], base)
M = M + 2
big_num = helpers.base_decode(big_str[i:], base)
z = big_num/const.y_factor
Dy_min = big_num - const.y_factor * z
big_num = z
z = big_num/const.x_factor
Dx_min = big_num - const.x_factor * z
big_num = z
deltas = []
flagged = False
while big_num > 0:
m = big_num % M
big_num = big_num / M
deltas.append(int(m))
deltas = deltas[::-1]
deltas[0] -= 1
deltas[1] -= 1
if deltas == coords:
return True
def invert_golomb_trans(s, base, e):
bs = e
result = ''
count = 0
m = 2**e
d = helpers.base_decode(s, base)
b = bin(d)[3:]
while count < 2:
zi = b.find('0')
if zi:
b = b[zi+1:]
v = (zi*m + int(b[:bs], 2)) * m
v += int(b[bs:2*bs], 2)
else:
b = b[zi+1:]
v = int(b[:bs], 2) * m
v += int(b[bs:2*bs], 2)
b = b[2*bs:]
result += str(v) + ','
count += 1
while b:
zi = b.find('0')
b = b[zi+1:]
result += str(zi*m + int(b[:bs], 2)) + ','
b = b[bs:]
return ''.join(result[:-1])
def invert_golomb_trans(s, base, e):
bs = e
result = ''
count = 0
m = 2**e
d = helpers.base_decode(s, base)
b = bin(d)[3:]
while count < 2:
zi = b.find('0')
if zi:
b = b[zi+1:]
v = (zi*m + int(b[:bs], 2)) * m
v += int(b[bs:2*bs], 2)
else:
b = b[zi+1:]
v = int(b[:bs], 2) * m
v += int(b[bs:2*bs], 2)
b = b[2*bs:]
result += str(v) + ','
count += 1
while b:
zi = b.find('0')
b = b[zi+1:]
result += str(zi*m + int(b[:bs], 2)) + ','
b = b[bs:]
return ''.join(result[:-1])
