Google Maps API V3学习（事例不断增加中）

如果知道两点的坐标，如何求两点之间的距离？ 新手较菜忽喷~~

mysql function 实现版本


CREATE DEFINER=`root`@`%` FUNCTION `F_calculate_distance`(Lat1 float,Lon1 float,Lat2 float,Lon2 float) RETURNS float
BEGIN

declare ret float;

declare r float;

declare A float;

declare B float;

declare RA float;

declare RB float;

declare RL1 float;

declare RL2 float;

set  r = 6378137;

set  A = abs(Lat1 - Lat2);

set  B = abs(Lon1 - Lon2);

set  RA = A * pi() / 180.0;

set RB = B * pi() / 180.0;

set  RL1 = Lat1 * pi() / 180.0;

set  RL2 = Lat2 * pi() / 180.0;

set  ret = cast(2 * r * asin(sqrt(sin(RA/2) * sin(RA/2) + cos(RL1) * cos(RL2) * sin(RB/2) * sin(RB/2))) as decimal(8,0));

return ret;

END;