// 坐标转换
GPS转百度
var location = transformFromWGS84ToBaidu(Float,Float);
console.log(location.lat + " _ " + location.lng);
百度转GPS
var location = transformFromBaiduToWGS84(Float,Float);
console.log(location.lat + " _ " + location.lng);
/**
*
* 计算两个坐标之间距离（米）
*
*/
public class DistUtil
{
/**
* @param args
*/
public static void main(String[] args)
{
double[] a = {84.74704, 44.429556};
double[] b = {84.721156, 44.450052};
double[] c = {84.742773, 44.432865};
// a点 -- b点 实时上报c点
int ac = (int)DistUtil.LantitudeLongitudeDists(a, c);
int cb = (int)DistUtil.LantitudeLongitudeDists(c, b);
int ab = (int)DistUtil.LantitudeLongitudeDists(a, b);
System.out.println(ac + "_" + cb + "_" + ab);
if (ac + cb < ab + 10)
{
System.out.println("OK");
}
}
public static double LantitudeLongitudeDists(double[] a, double[] b)
{
return LantitudeLongitudeDist(a[0], a[1], b[0], b[1]);
}
private static final double EARTH_RADIUS = 6378137;// 赤道半径(单位m)
/**
* 转化为弧度(rad)
*/
private static double rad(double d)
{
return d * Math.PI / 180.0;
}
/**
* 基于余弦定理求两经纬度距离
*
* @param lon1 第一点的精度
* @param lat1 第一点的纬度
* @param lon2 第二点的精度
* @param lat3 第二点的纬度
* @return 返回的距离，单位km
*/
public static double LantitudeLongitudeDist(double lon1, double lat1, double lon2, double lat2)
{
double radLat1 = rad(lat1);
double radLat2 = rad(lat2);
double radLon1 = rad(lon1);
double radLon2 = rad(lon2);
if (radLat1 < 0)
radLat1 = Math.PI / 2 + Math.abs(radLat1);// south
if (radLat1 > 0)
radLat1 = Math.PI / 2 - Math.abs(radLat1);// north
if (radLon1 < 0)
radLon1 = Math.PI * 2 - Math.abs(radLon1);// west
if (radLat2 < 0)
radLat2 = Math.PI / 2 + Math.abs(radLat2);// south
if (radLat2 > 0)
radLat2 = Math.PI / 2 - Math.abs(radLat2);// north
if (radLon2 < 0)
radLon2 = Math.PI * 2 - Math.abs(radLon2);// west
double x1 = EARTH_RADIUS * Math.cos(radLon1) * Math.sin(radLat1);
double y1 = EARTH_RADIUS * Math.sin(radLon1) * Math.sin(radLat1);
double z1 = EARTH_RADIUS * Math.cos(radLat1);
double x2 = EARTH_RADIUS * Math.cos(radLon2) * Math.sin(radLat2);
double y2 = EARTH_RADIUS * Math.sin(radLon2) * Math.sin(radLat2);
double z2 = EARTH_RADIUS * Math.cos(radLat2);
double d = Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2) + (z1 - z2) * (z1 - z2));
// 余弦定理求夹角
double theta = Math.acos((EARTH_RADIUS * EARTH_RADIUS + EARTH_RADIUS * EARTH_RADIUS - d * d) / (2 * EARTH_RADIUS * EARTH_RADIUS));
double dist = theta * EARTH_RADIUS;
return dist;
}
}