/// <summary>
/// Shortens the full code by removing four or six digits, depending on the provided reference point
/// </summary>
/// <param name="latitude">Reference location latitude</param>
/// <param name="longitude">Reference location longitude</param>
/// <returns>Returns a new Open Location Code with less digits</returns>
public static OpenLocationCode Shorten(this OpenLocationCode code, double latitude, double longitude)
{
if (!code.IsFull)
{
throw new InvalidOperationException("Can only shorten a full Open Location Code.");
}
if (code.IsPadded)
{
throw new InvalidOperationException("Can only shorten an Open Location Code that isn't padded.");
}
Bounds bounds = code.Decode();
double latitudeDiff = Math.Abs(latitude - bounds.CenterLatitude);
double longitudeDiff = Math.Abs(longitude - bounds.CenterLongitude);
if (latitudeDiff < Constants.LatitudePrecision8Digits && longitudeDiff < Constants.LatitudePrecision8Digits)
{
return(new OpenLocationCode(code.Code.Substring(8)));
}
else if (latitudeDiff < Constants.LatitudePrecision6Digits && longitudeDiff < Constants.LatitudePrecision6Digits)
{
return(new OpenLocationCode(code.Code.Substring(6)));
}
else if (latitudeDiff < Constants.LatitudePrecision4Digits && longitudeDiff < Constants.LatitudePrecision4Digits)
{
return(new OpenLocationCode(code.Code.Substring(4)));
}
throw new ArgumentException("Location is too far from the Open Location Code center.");
}
public static OpenLocationCode Recover(this OpenLocationCode code, double latitude, double longitude)
{
if (code.IsFull)
{
return(code);
}
latitude = Builder.ClipLatitude(latitude);
longitude = Builder.NormalizeLongitude(longitude);
int digitsToRecover = 8 - code.Code.IndexOf(Constants.Separator);
double paddedArea = Math.Pow(20, 2 - (digitsToRecover / 2));
// use reference location to pad the supplied code
string prefix = OpenLocationCode.Encode(latitude, longitude)
.Substring(0, digitsToRecover);
var recoveredCode = new OpenLocationCode(prefix + code.Code);
var recoveredCodeBounds = recoveredCode.Decode();
double recoveredLatitude = recoveredCodeBounds.CenterLatitude;
double recoveredLongitude = recoveredCodeBounds.CenterLongitude;
// adjust latitude resolution
double latitudeDiff = recoveredLatitude - latitude;
if (latitudeDiff > (paddedArea / 2))
{
recoveredLatitude -= paddedArea;
}
else if (latitudeDiff < (-paddedArea / 2))
{
recoveredLatitude += paddedArea;
}
// adjust longitude resolution
double longitudeDiff = recoveredLongitude - longitude;
if (longitudeDiff > (paddedArea / 2))
{
recoveredLongitude -= paddedArea;
}
else if (longitudeDiff < (-paddedArea / 2))
{
recoveredLongitude += paddedArea;
}
return(new OpenLocationCode(recoveredLatitude, recoveredLongitude, recoveredCode.Code.Length - 1));
}