unity 两点距离 unity求两点距离

计算地图上两点间的距离，使用的是谷歌地图

class GeoHelper
{
/**
* @param int $lat1
* @param int $lon1
* @param int $lat2
* @param int $lon2
* @param string $unit
* @return
*/
public static function distance($lat1, $lon1, $lat2, $lon2, $unit = "K")
{
$theta = $lon1 - $lon2;
$dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) + cos(deg2rad($lat1)) * cos(deg2rad
($lat2)) * cos(deg2rad($theta));
$dist = acos($dist);
$dist = rad2deg($dist);
$miles = $dist * 60 * 1.1515;
$unit = strtoupper($unit);
if ($unit == "K") {
return ($miles * 1.609344);
} else
if ($unit == "N") {
return ($miles * 0.8684);
} else { //mi
return $miles;
}
}
/**
*
* @param string $address
* @param string $apikey
* @return array [1]:lat [0]:lng
*/
public static function getLatLng($address, $apikey)
{
$find = array("\\n", "\\r", " ");
$replace = array("", "", "+");
$address = str_replace($find, $replace, $address);
$url = 'http://maps.google.com/maps/geo?q=' . $address . '&key=' . $apikey .
'&sensor=false&output=xml&oe=utf8';
$response = self::xml2array($url);
$coordinates = $response['kml']['Response']['Placemark']['Point']['coordinates'];
if (!empty($coordinates)) {
$point_array = split(",", $coordinates);
return $point_array;
}
}
}

利用JS实现的根据经纬度计算地球上两点之间的距离