緯度と経度とウェブメルカトル図法の間の変換

        public static double[] Mercator2LonLat(double X, double Y)
        {
            double[] d = new double[2];
            double x = X / 20037508.34 * 180;
            double y = Y / 20037508.34 * 180;
            y = 180 / Math.PI * (2 * Math.Atan(Math.Exp(y * Math.PI / 180)) - Math.PI / 2);
            d[0] = x;
            d[1] = y;
            return d;
        }

        public static double[] LonLat2Mercator(double X, double Y)
        {
            double[] d = new double[2];
            double x = X * 20037508.34 / 180;
            double y = Math.Log(Math.Tan((90 + Y) * Math.PI / 360)) / (Math.PI / 180);
            y = y * 20037508.34 / 180;
            d[0] = x;
            d[1] = y;
            return d;
        }