【实测可用】GPS纠偏算法-Java版

GPS纠偏算法-Java版

用于WGS-84（地球坐标系）与GCJ-02（火星坐标系）的互转：

package com.xxx.utils;

/**
 * gps纠偏算法，适用于google,高德体系的地图
 */
public abstract class GpsUtil {

	private final static double a = 6378245.0;
	private final static double pi = 3.14159265358979324;
	private final static double ee = 0.00669342162296594323;

	/**
	 * 计算地球上任意两点(经纬度)距离
	 * 
	 * @param long1
	 *            第一点经度
	 * 
	 * @param lat1
	 *            第一点纬度
	 * 
	 * @param long2
	 *            第二点经度
	 * 
	 * @param lat2
	 *            第二点纬度
	 * 
	 * @return 返回距离 单位：米
	 */
	public static double distance(double long1, double lat1, double long2, double lat2) {
		double a, b, R;
		R = 6378137; // 地球半径
		lat1 = lat1 * Math.PI / 180.0;
		lat2 = lat2 * Math.PI / 180.0;
		a = lat1 - lat2;
		b = (long1 - long2) * Math.PI / 180.0;
		double d;
		double sa2, sb2;
		sa2 = Math.sin(a / 2.0);
		sb2 = Math.sin(b / 2.0);
		d = 2 * R * Math.asin(Math.sqrt(sa2 * sa2 + Math.cos(lat1) * Math.cos(lat2) * sb2 * sb2));
		return d;
	}

	/** WGS-84 to GCJ-02 */
	public static double[] toGCJ02Point(double latitude, double longitude) {
		double[] dev = calDev(latitude, longitude);
		double retLat = latitude + dev[0];
		double retLon = longitude + dev[1];
		return new double[] { retLat, retLon };
	}

	/** GCJ-02 to WGS-84 */
	public static double[] toWGS84Point(double latitude, double longitude) {
		double[] dev = calDev(latitude, longitude);
		double retLat = latitude - dev[0];
		double retLon = longitude - dev[1];
		dev = calDev(retLat, retLon);
		retLat = latitude - dev[0];
		retLon = longitude - dev[1];
		return new double[] { retLat, retLon };
	}

	private static double[] calDev(double wgLat, double wgLon) {
		if (isOutOfChina(wgLat, wgLon)) {
			return new double[] { 0, 0 };
		}
		double dLat = calLat(wgLon - 105.0, wgLat - 35.0);
		double dLon = calLon(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);
		return new double[] { dLat, dLon };
	}

	private static boolean isOutOfChina(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 calLat(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 calLon(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;
	}

}