/*********GCJ-02 to WGS-84*******/
this.GcjToWgs = function(Longitude,Latitude)
{
    var Dev = CalDev(Longitude,Latitude);


    var RetLat = Latitude - Dev.Lat;


    var RetLon = Longitude - Dev.Lon;


    Dev = this.CalDev(RetLon,RetLat);


    RetLat = Latitude - Dev.Lat;


    RetLon = Longitude - Dev.Lon;


    return {Lon:RetLon,Lat:RetLat};
}
/*********計算偏差***************/
this.CalDev = function(WgLon,WgLat)
{
    var ee = 0.00669342162296594323;


    var a = 6378245.0;


    if (IsOutOfChina(WgLon,WgLat))
    {
        return {Lon:0,Lat:0};
    }
    var Lat = CalLat(WgLon - 105.0, WgLat - 35.0);


    var Lon = CalLon(WgLon - 105.0, WgLat - 35.0);


    var RadLat = WgLat / 180.0 * Math.PI;


    var Magic = Math.sin(RadLat);


    Magic = 1 - ee * Magic * Magic;


    var sqrtMagic = Math.sqrt(Magic);


    Lat = (Lat * 180.0) / ((a * (1 - ee)) / (Magic * sqrtMagic) * Math.PI);


    Lon = (Lon * 180.0) / (a / sqrtMagic * Math.cos(RadLat) * Math.PI);


    return  {Lon:Lon,Lat:Lat};
}


/******判斷座標是否在國外******/
this.IsOutOfChina = function(Lon,Lat)
{
    if (Lon < 72.004 || Lon > 137.8347)
    {
        return true;
    }
    if (Lat < 0.8293 || Lat > 55.8271)
    {
        return true;
    }


    return false;
}


/****** 計算緯度******/
this.CalLat = function(X, Y)
{
    var ResultLat = -100.0 + 2.0 * X + 3.0 * Y + 0.2 * Y * Y + 0.1 * X * Y + 0.2 * Math.sqrt(Math.abs(X));


    ResultLat += (20.0 * Math.sin(6.0 * X * Math.PI) + 20.0 * Math.sin(2.0 * X * Math.PI)) * 2.0 / 3.0;


    ResultLat += (20.0 * Math.sin(Y * Math.PI) + 40.0 * Math.sin(Y / 3.0 * Math.PI)) * 2.0 / 3.0;


    ResultLat += (160.0 * Math.sin(Y / 12.0 * Math.PI) + 320 * Math.sin(Y * Math.PI / 30.0)) * 2.0 / 3.0;


    return ResultLat;
}


 /******計算經度******/
this.CalLon = function(X, Y)
{
    var ResultLon = 300.0 + X + 2.0 * Y + 0.1 * X * X + 0.1 * X * Y + 0.1 * Math.sqrt(Math.abs(X));


    ResultLon += (20.0 * Math.sin(6.0 * X * Math.PI) + 20.0 * Math.sin(2.0 * X * Math.PI)) * 2.0 / 3.0;


    ResultLon += (20.0 * Math.sin(X * Math.PI) + 40.0 * Math.sin(X / 3.0 * Math.PI)) * 2.0 / 3.0;


    ResultLon += (150.0 * Math.sin(X / 12.0 * Math.PI) + 300.0 * Math.sin(X / 30.0 * Math.PI)) * 2.0 / 3.0;


    return ResultLon;

}

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