gps坐标系转百度坐标系（超级准）

上java代码

/**
 * gps转百度坐标系
 * @author ardo
 * 
 * WGS-84：是国际标准，GPS坐标（Google Earth使用、或者GPS模块） 
	GCJ-02：中国坐标偏移标准，Google 
	Map、高德、腾讯使用 BD-09：百度坐标偏移标准，Baidu Map使用
	
	pi: 圆周率。
	a: 卫星椭球坐标投影到平面地图坐标系的投影因子。
	ee: 椭球的偏心率。
	x_pi: 圆周率转换量。
	transformLat(lat, lon): 转换方法，比较复杂，不必深究了。输入：横纵坐标，输出：转换后的横坐标。
	transformLon(lat, lon): 转换方法，同样复杂，自行脑补吧。输入：横纵坐标，输出：转换后的纵坐标。
	wgs2gcj(lat, lon): WGS坐标转换为GCJ坐标。
	gcj2bd(lat, lon): GCJ坐标转换为百度坐标。
	
	出现差错的 把 x的 y位置调一下
 *
 */
public class GpsToBaidu {
	
	static double pi = 3.14159265358979324;
	static double a = 6378245.0;
	static double ee = 0.00669342162296594323;
	public final static double x_pi = 3.14159265358979324 * 3000.0 / 180.0;
	
	public static void main(String[] args) {
		double[] point = wgs2bd(39.042366, 117.224174);
		System.out.println("y=" + point[0] + " x=" + point[1]);
		//117.2368628208316,39.04962672134104 -quanlei
		//117.2368519061299,39.04963023317262 -转后
	}
	
	public static double[] wgs2bd(double lat, double lon) {
	       double[] wgs2gcj = wgs2gcj(lat, lon);
	       double[] gcj2bd = gcj2bd(wgs2gcj[0], wgs2gcj[1]);
	       return gcj2bd;
	}

	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 };
	}

	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;
	}

}