关于地图中，各个地图系相互转换的方法，此处是复制别人的，仅作收藏。
在转换过程中一度出现精度偏差的情况，这里要注意 pi 的取值，原博客没有注意此问题，在应用的过程中纠结了很久。
/** * 各地图API坐标系统比较与转换; * WGS84坐标系：即地球坐标系，国际上通用的坐标系。设备一般包含GPS芯片或者北斗芯片获取的经纬度为WGS84地理坐标系, * 谷歌地图采用的是WGS84地理坐标系（中国范围除外）; * GCJ02坐标系：即火星坐标系，是由中国国家测绘局制订的地理信息系统的坐标系统。由WGS84坐标系经加密后的坐标系。 * 谷歌中国地图和搜搜中国地图采用的是GCJ02地理坐标系; BD09坐标系：即百度坐标系，GCJ02坐标系经加密后的坐标系; * 搜狗坐标系、图吧坐标系等，估计也是在GCJ02基础上加密而成的。 chenhua */ public class PositionUtil { public static final String BAIDU_LBS_TYPE = "bd09ll"; public static double pi = 3.1415926535897932384626 * 3000.0 / 180.0; //此处注意 pi = 派 * 3000 / 180 ; public static double a = 6378245.0; public static double ee = 0.00669342162296594323; /** * 84 to 火星坐标系 (GCJ-02) World Geodetic System ==> Mars Geodetic System * * @param lat * @param lon * @return */ public static Gps gps84_To_Gcj02(double lat, double lon) { if (outOfChina(lat, lon)) { return null; } 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; return new Gps(mgLat, mgLon); } /** * * 火星坐标系 (GCJ-02) to 84 * * @param lon * @param lat * @return * */ public static Gps gcj_To_Gps84(double lat, double lon) { Gps gps = transform(lat, lon); double lontitude = lon * 2 - gps.getWgLon(); double latitude = lat * 2 - gps.getWgLat(); return new Gps(latitude, lontitude); } /** * 火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法 将 GCJ-02 坐标转换成 BD-09 坐标 * * @param gg_lat * @param gg_lon */ public static Gps gcj02_To_Bd09(double gg_lat, double gg_lon) { double x = gg_lon, y = gg_lat; double z = Math.sqrt(x * x + y * y) + 0.00002 * Math.sin(y * pi); double theta = Math.atan2(y, x) + 0.000003 * Math.cos(x * pi); double bd_lon = z * Math.cos(theta) + 0.0065; double bd_lat = z * Math.sin(theta) + 0.006; return new Gps(bd_lat, bd_lon); } /** * * 火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法 * * 将 BD-09 坐标转换成GCJ-02 坐标 * * @param * bd_lat * @param bd_lon * @return */ public static Gps bd09_To_Gcj02(double bd_lat, double bd_lon) { double x = bd_lon - 0.0065, y = bd_lat - 0.006; double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * pi); double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * pi); double gg_lon = z * Math.cos(theta); double gg_lat = z * Math.sin(theta); return new Gps(gg_lat, gg_lon); } /** * (BD-09)-->84 * @param bd_lat * @param bd_lon * @return */ public static Gps bd09_To_Gps84(double bd_lat, double bd_lon) { Gps gcj02 = PositionUtil.bd09_To_Gcj02(bd_lat, bd_lon); Gps map84 = PositionUtil.gcj_To_Gps84(gcj02.getWgLat(), gcj02.getWgLon()); return map84; } public static boolean outOfChina(double lat, double lon) { if (lon < 72.004 || lon > 137.8347) return true; if (lat < 0.8293 || lat > 55.8271) return true; return false; } public static Gps transform(double lat, double lon) { if (outOfChina(lat, lon)) { return new Gps(lat, 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; return new Gps(mgLat, mgLon); } public static double transformLat(double x, double y) { double ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * Math.sqrt(Math.abs(x)); ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0; ret += (20.0 * Math.sin(y * pi) + 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0; ret += (160.0 * Math.sin(y / 12.0 * pi) + 320 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0; return ret; } public static double transformLon(double x, double y) { double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * Math.sqrt(Math.abs(x)); ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0; ret += (20.0 * Math.sin(x * pi) + 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0; ret += (150.0 * Math.sin(x / 12.0 * pi) + 300.0 * Math.sin(x / 30.0 * pi)) * 2.0 / 3.0; return ret; } public static void main(String[] args) { // 北斗芯片获取的经纬度为WGS84地理坐标 31.426896,119.496145 Gps gps = new Gps(31.426896, 119.496145); System.out.println("gps :" + gps); Gps gcj = gps84_To_Gcj02(gps.getWgLat(), gps.getWgLon()); System.out.println("gcj :" + gcj); Gps star = gcj_To_Gps84(gcj.getWgLat(), gcj.getWgLon()); System.out.println("star:" + star); Gps bd = gcj02_To_Bd09(gcj.getWgLat(), gcj.getWgLon()); System.out.println("bd :" + bd); Gps gcj2 = bd09_To_Gcj02(bd.getWgLat(), bd.getWgLon()); System.out.println("gcj :" + gcj2); } }
public class Gps { private double wgLat; private double wgLon; public Gps(double wgLat, double wgLon) { setWgLat(wgLat); setWgLon(wgLon); } public double getWgLat() { return wgLat; } public void setWgLat(double wgLat) { this.wgLat = wgLat; } public double getWgLon() { return wgLon; } public void setWgLon(double wgLon) { this.wgLon = wgLon; } @Override public String toString() { return wgLat + "," + wgLon; } }