y <<= (32 - z)
# project the parameters back to their coordinate ranges.
- [(x * 360.0 / 2**32) - 180.0,
- (y * 180.0 / 2**32) - 90.0,
+ [(x * 360.0 / (2**32)) - 180.0,
+ (y * 180.0 / (2**32)) - 90.0,
z - 8 - (z_offset % 3)]
end
##
# given a location and zoom, return a short string representing it.
def encode(lon, lat, z)
- code = interleave_bits(((lon + 180.0) * 2**32 / 360.0).to_i,
- ((lat + 90.0) * 2**32 / 180.0).to_i)
+ code = interleave_bits(((lon + 180.0) * (2**32) / 360.0).to_i,
+ ((lat + 90.0) * (2**32) / 180.0).to_i)
str = ""
# add eight to the zoom level, which approximates an accuracy of
# one pixel in a tile.
((z + 8) / 3.0).ceil.times do |i|
- digit = (code >> (58 - 6 * i)) & 0x3f
+ digit = (code >> (58 - (6 * i))) & 0x3f
str << ARRAY[digit]
end
# append characters onto the end of the string to represent