火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法

 include

 const double x_pi = 3.14159265358979324 * 3000.0 / 180.0;

 void bd_encrypt(double gg_lat, double gg_lon, double &bd_lat, double &bd_lon)
 {
     double x = gg_lon, y = gg_lat;
     double z = sqrt(x * x + y * y) + 0.00002 * sin(y * x_pi);
     double theta = atan2(y, x) + 0.000003 * cos(x * x_pi);
     bd_lon = z * cos(theta) + 0.0065;
     bd_lat = z * sin(theta) + 0.006;
 }

 void bd_decrypt(double bd_lat, double bd_lon, double &gg_lat, double &gg_lon)
 {
     double x = bd_lon - 0.0065, y = bd_lat - 0.006;
     double z = sqrt(x * x + y * y) - 0.00002 * sin(y * x_pi);
     double theta = atan2(y, x) - 0.000003 * cos(x * x_pi);
     gg_lon = z * cos(theta);
     gg_lat = z * sin(theta);
 }