private static Zone GetZoneByLocation(double lon, double lat, int level)
{
if (lat < -90 || lat > 90 || lon < -180 || lon > 180 || level < 0 || level > 15)
{
return(null);
}
level += 2;
double h_size = Calculations.CalcHexSize(level);
XY z_xy = Calculations.Loc2Xy(lon, lat);
double lon_grid = z_xy.x;
double lat_grid = z_xy.y;
double unit_x = 6 * h_size;
double unit_y = 6 * h_size * Constants.h_k;
double h_pos_x = (lon_grid + lat_grid / Constants.h_k) / unit_x;
double h_pos_y = (lat_grid - Constants.h_k * lon_grid) / unit_y;
double h_x_0 = Math.Floor(h_pos_x);
double h_y_0 = Math.Floor(h_pos_y);
double h_x_q = h_pos_x - h_x_0;
double h_y_q = h_pos_y - h_y_0;
double h_x = Math.Round(h_pos_x);
double h_y = Math.Round(h_pos_y);
if (h_y_q > -h_x_q + 1)
{
if ((h_y_q < 2 * h_x_q) && (h_y_q > 0.5 * h_x_q))
{
h_x = h_x_0 + 1;
h_y = h_y_0 + 1;
}
}
else if (h_y_q < -h_x_q + 1)
{
if ((h_y_q > (2 * h_x_q) - 1) && (h_y_q < (0.5 * h_x_q) + 0.5))
{
h_x = h_x_0;
h_y = h_y_0;
}
}
double h_lat = (Constants.h_k * h_x * unit_x + h_y * unit_y) / 2;
double h_lon = (h_lat - h_y * unit_y) / Constants.h_k;
Location z_loc = Calculations.XyToLoc(h_lon, h_lat);
double z_loc_x = z_loc.Longitude;
double z_loc_y = z_loc.Latitude;
if (Constants.h_base - h_lon < h_size)
{
z_loc_x = 180;
double h_xy = h_x;
h_x = h_y;
h_y = h_xy;
}
StringBuilder h_code = new StringBuilder();
List <Int32> code3_x = new List <Int32>();
List <Int32> code3_y = new List <Int32>();
StringBuilder code3 = new StringBuilder();
StringBuilder code9 = new StringBuilder();
double mod_x = h_x;
double mod_y = h_y;
for (int i = 0; i <= level; i++)
{
double h_pow = Math.Pow(3, level - i);
if (mod_x >= Math.Ceiling(h_pow / 2))
{
code3_x.Add(2);
mod_x -= h_pow;
}
else if (mod_x <= -Math.Ceiling(h_pow / 2))
{
code3_x.Add(0);
mod_x += h_pow;
}
else
{
code3_x.Add(1);
}
if (mod_y >= Math.Ceiling(h_pow / 2))
{
code3_y.Add(2);
mod_y -= h_pow;
}
else if (mod_y <= -Math.Ceiling(h_pow / 2))
{
code3_y.Add(0);
mod_y += h_pow;
}
else
{
code3_y.Add(1);
}
}
for (int i = 0; i < code3_x.Count; i++)
{
code3.Append("" + code3_x[i] + code3_y[i]);
//Convert to terneral (Base 3) not standard supported in .Net
code9.Append(BaseConverter.BaseStringToValue(code3.ToString(), 3));
h_code.Append(code9);
code9.Length = 0;
code3.Length = 0;
}
String h_2 = h_code.ToString(3, (h_code.Length) - 3);
int h_1 = Convert.ToInt32(h_code.ToString(0, 3));
int h_a1 = (int)Math.Floor((double)h_1 / 30);
int h_a2 = h_1 % 30;
StringBuilder h_code_r = new StringBuilder();
h_code_r.Append(Constants.h_key[h_a1]).Append(Constants.h_key[h_a2]).Append(h_2.ToString());
return(new Zone(z_loc_y, z_loc_x, h_x, h_y, h_code_r.ToString()));
}
private static Zone GetZoneByCode(String code)
{
int level = code.Length;
double h_size = Calculations.CalcHexSize(level);
double unit_x = 6 * h_size;
double unit_y = 6 * h_size * Constants.h_k;
double h_x = 0;
double h_y = 0;
string h_dec9 = "" + (Constants.h_key.IndexOf(code[0]) * 30 + Constants.h_key.IndexOf(code[1].ToString()) + "") + code.Substring(2);
if (h_dec9.Length >= 3)
{
if (RegMatch(h_dec9[0], INC15) && RegMatch(h_dec9[1], EXC125) && RegMatch(h_dec9[2], EXC125))
{
if (h_dec9[0] == '5')
{
h_dec9 = "7" + h_dec9.Substring(1, h_dec9.Length - 1);
}
else if (h_dec9[0] == '1')
{
h_dec9 = "3" + h_dec9.Substring(1, h_dec9.Length - 1);
}
}
}
int d9xlen = h_dec9.Length;
for (int i = 0; i < level + 1 - d9xlen; i++)
{
h_dec9 = "0" + h_dec9;
d9xlen++;
}
StringBuilder h_dec3 = new StringBuilder();
for (int i = 0; i < d9xlen; i++)
{
String h_dec0 = BaseConverter.NumberToBaseString(h_dec9[i].ToString(), 3).ToString();
if (h_dec0.Length == 1)
{
h_dec3.Append("0");
}
h_dec3.Append(h_dec0);
}
List <char> h_decx = new List <char>();
List <char> h_decy = new List <char>();
for (int i = 0; i < h_dec3.Length / 2; i++)
{
h_decx.Add(h_dec3[i * 2]);
h_decy.Add(h_dec3[(i * 2 + 1)]);
}
for (int i = 0; i <= level; i++)
{
double h_pow = Math.Pow(3, level - i);
if (h_decx[i] == '0')
{
h_x -= h_pow;
}
else if (h_decx[i] == '2')
{
h_x += h_pow;
}
if (h_decy[i] == '0')
{
h_y -= h_pow;
}
else if (h_decy[i] == '2')
{
h_y += h_pow;
}
}
double h_lat_y = (Constants.h_k * h_x * unit_x + h_y * unit_y) / 2;
double h_lon_x = (h_lat_y - h_y * unit_y) / Constants.h_k;
Location h_loc = Calculations.XyToLoc(h_lon_x, h_lat_y);
if (h_loc.Longitude > 180)
{
h_loc.Longitude -= 360;
}
else if (h_loc.Longitude < -180)
{
h_loc.Longitude += 360;
}
return(new Zone(h_loc.Latitude, h_loc.Longitude, h_x, h_y, code));
}