Google地图百度地图GPS经纬度偏移转换(JAVA)

注：用将代码从Java转成C#验证了WGS-84 到 GCJ-02 的转换（即 GPS 加偏），效果不是特别理想，仍然有部分偏移。先凑合一下，后面再想其他离线地图解决办法。。

转：Google地图百度地图GPS经纬度偏移转换(JAVA)

主要就是Google地图，百度地图，GPS经纬度偏移转换

GCJ-02转换BD-09,Google地图经纬度转百度地图经纬度
BD-09转换GCJ-02,百度转google
WGS-84 到 GCJ-02 的转换（即 GPS 加偏）

/**
 * 用于构造地图中的坐标点
 * @author lw
 * **/
public class Point {
     
    private double lat;// 纬度
    private double lng;// 经度
     
    public Point() {
    }
     
    public Point(double lng, double lat) {
        this.lng = lng;
        this.lat = lat;
    }
 
    @Override
    public boolean equals(Object obj) {
        if (obj instanceof Point) {
            Point bmapPoint = (Point) obj;
            return (bmapPoint.getLng() == lng && bmapPoint.getLat() == lat) ? true : false;
        } else {
            return false;
        }
    }
     
    public double getLat() {
        return lat;
    }
    public void setLat(double lat) {
        this.lat = lat;
    }
    public double getLng() {
        return lng;
    }
    public void setLng(double lng) {
        this.lng = lng;
    }
     
    @Override
    public String toString() {
        return "Point [lat=" + lat + ", lng=" + lng + "]";
    }
     
}

/**
 * 地图坐标转换 google,baidu,gps
 * @author lw
 * @Time 2015年4月16日18:19:16
 * 
 * */
public class CoordinateConversion {
    private static final double x_pi = 3.14159265358979324 * 3000.0 / 180.0;
     
    private static final double pi = 3.14159265358979324;
    private static final double a = 6378245.0;
    private static final double ee = 0.00669342162296594323;
     
    /**
     * gg_lat 纬度
     * gg_lon 经度
     * GCJ-02转换BD-09
     * Google地图经纬度转百度地图经纬度
     * */
    public static Point google_bd_encrypt(double gg_lat, double gg_lon){
        Point point=new Point();
        double x = gg_lon, y = gg_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;
        point.setLat(bd_lat);
        point.setLng(bd_lon);
        return point;
    }
     
    /**
     * wgLat 纬度
     * wgLon 经度
     * BD-09转换GCJ-02
     * 百度转google
     * */
    public static Point bd_google_encrypt(double bd_lat, double bd_lon){
        Point point=new Point();
        double x = bd_lon - 0.0065, y = bd_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);  
        point.setLat(gg_lat);
        point.setLng(gg_lon);
        return point;
    }
     
     
     
    /**
     * wgLat 纬度
     * wgLon 经度
     * WGS-84 到 GCJ-02 的转换（即 GPS 加偏）
     * */
    public static Point wgs_gcj_encrypts(double wgLat, double wgLon) {
        Point point=new Point();
        if (outOfChina(wgLat, wgLon)) {
            point.setLat(wgLat);
            point.setLng(wgLon);
            return point;
        }
        double dLat = transformLat(wgLon - 105.0, wgLat - 35.0);
        double dLon = transformLon(wgLon - 105.0, wgLat - 35.0);
        double radLat = wgLat / 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 lat = wgLat + dLat;
        double lon = wgLon + dLon;
        point.setLat(lat);
        point.setLng(lon);
        return point;
    }
     
     
    public static void transform(double wgLat, double wgLon, double[] latlng) {
        if (outOfChina(wgLat, wgLon)) {
            latlng[0] = wgLat;
            latlng[1] = wgLon;
            return;
        }
        double dLat = transformLat(wgLon - 105.0, wgLat - 35.0);
        double dLon = transformLon(wgLon - 105.0, wgLat - 35.0);
        double radLat = wgLat / 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);
        latlng[0] = wgLat + dLat;
        latlng[1] = wgLon + dLon;
    }
 
    private 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;
    }
 
    private 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;
    }
 
    private 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;
    }
}