Fil

<?php


/* is (lon, lat) inside the polygon $p?
 * use ray casting algorithm (http://en.wikipedia.org/wiki/Point_in_polygon)
 * ie. project a horizontal line from our point to each segment
 * code adapted from http://stackoverflow.com/questions/14149099/raycasting-algorithm-with-gps-coordinates
 */
function inside_polygon($test_point, $points) {