地球坐标系<WGS-84>转换到火星坐标系<GCJ-02>算法分析

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分析一下这段代码，在能明白的地方加点注释，诸位将就着看吧

//// Copyright (C) 1000 - 9999 Somebody Anonymous// NO WARRANTY OR GUARANTEE//using System;namespace Navi{    class EvilTransform    {        const double pi = 3.14159265358979324;        //        // Krasovsky 1940        //        // a = 6378245.0, 1/f = 298.3        // b = a * (1 - f)        // ee = (a^2 - b^2) / a^2;        const double a = 6378245.0;//参考椭球体半长径        const double ee = 0.00669342162296594323;//第一偏心率平方        //        // World Geodetic System ==> Mars Geodetic System        public static void transform(double wgLat, double wgLon, out double mgLat, out double mgLon)        {            if (outOfChina(wgLat, wgLon))            {//判断需要转换的坐标是否在中国境内，只有我大天朝使用此种加密方法                mgLat = wgLat;                mgLon = wgLon;                return;            }            double dLat = transformLat(wgLon - 105.0, wgLat - 35.0);//计算偏移量            double dLon = transformLon(wgLon - 105.0, wgLat - 35.0);            double radLat = wgLat / 180.0 * pi;//转换为度数            double magic = Math.Sin(radLat);//求正弦值            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);            mgLat = wgLat + dLat;            mgLon = wgLon + dLon;        }        static bool 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;        }        static double transformLat(double x, double y)        {//对纬度的初步处理函数            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;        }        static double transformLon(double x, double y)        {//对经度的初步处理函数            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;        }    }}

这是第一偏心率的解释（来自百度知道）

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