<?php
# Do steps 1-11 given here 
# https://developers.google.com/maps/documentation/utilities/polylinealgorithm
# in reverse order and inverted (i.e. left shift -> right shift, add -> subtract)

$string = "udgiEctkwIldeRe}|x@cfmXq|flA`nrvApihC";
# Step 11) unpack the string as unsigned char 'C'
$byte_array = array_merge(unpack('C*', $string));
$results = array();

$index = 0; # tracks which