坐标转换

static double pi = 3.14159265358979324;//圆周率
static double a = 6378140.0;//卫星椭球坐标投影到平面地图坐标系的投影因子
static double ee = 0.00669342162296594323;//椭球的偏心率
public final static double x_pi = 3.14159265358979324 * 3000.0 / 180.0;//圆周率转换量


public static double[] wgs2bd(double lat, double lon) {
      double[] wgs2gcj = wgs2gcj(lat, lon);
      double[] gcj2bd = gcj2bd(wgs2gcj[0], wgs2gcj[1]);
      return gcj2bd;
}


// GCJ坐标转换为百度坐标
public static double[] gcj2bd(double lat, double lon) {
      double x = lon, y = lat;
      double z = Math.sqrt(x * x + y * y) + 0.00002 * Math.sin(y * x_pi);
      double theta = Math.atan2(y, x) + 0.000003 * Math.cos(x * x_pi);
      double bd_lon = z * Math.cos(theta) + 0.0065;
      double bd_lat = z * Math.sin(theta) + 0.006;
      return new double[] { bd_lat, bd_lon };
}


public static double[] bd2gcj(double lat, double lon) {
      double x = lon - 0.0065, y = lat - 0.006;
      double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * x_pi);
      double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * x_pi);
      double gg_lon = z * Math.cos(theta);
      double gg_lat = z * Math.sin(theta);
      return new double[] { gg_lat, gg_lon };
}


// WGS坐标转换为GCJ坐标
public static double[] wgs2gcj(double lat, double lon) {
      double dLat = transformLat(lon - 105.0, lat - 35.0);
      double dLon = transformLon(lon - 105.0, lat - 35.0);
      double radLat = lat / 180.0 * pi;
      double magic = Math.sin(radLat);
      magic = 1 - ee * magic * magic;
      double sqrtMagic = Math.sqrt(magic);
      dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
      dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
      double mgLat = lat + dLat;
      double mgLon = lon + dLon;
      double[] loc = { mgLat, mgLon };
      return loc;
}


private static double transformLat(double lat, double lon) {
      double ret = -100.0 + 2.0 * lat + 3.0 * lon + 0.2 * lon * lon + 0.1 * lat * lon + 0.2 * Math.sqrt(Math.abs


(lat));
      ret += (20.0 * Math.sin(6.0 * lat * pi) + 20.0 * Math.sin(2.0 * lat * pi)) * 2.0 / 3.0;
      ret += (20.0 * Math.sin(lon * pi) + 40.0 * Math.sin(lon / 3.0 * pi)) * 2.0 / 3.0;
      ret += (160.0 * Math.sin(lon / 12.0 * pi) + 320 * Math.sin(lon * pi  / 30.0)) * 2.0 / 3.0;
      return ret;
}


private static double transformLon(double lat, double lon) {
      double ret = 300.0 + lat + 2.0 * lon + 0.1 * lat * lat + 0.1 * lat * lon + 0.1 * Math.sqrt(Math.abs(lat));
      ret += (20.0 * Math.sin(6.0 * lat * pi) + 20.0 * Math.sin(2.0 * lat * pi)) * 2.0 / 3.0;
      ret += (20.0 * Math.sin(lat * pi) + 40.0 * Math.sin(lat / 3.0 * pi)) * 2.0 / 3.0;
      ret += (150.0 * Math.sin(lat / 12.0 * pi) + 300.0 * Math.sin(lat / 30.0 * pi)) * 2.0 / 3.0;
      return ret;
}