/// <returns>
/// A new OpenLocationCode instance representing a full Open Location Code from this
/// (short) Open Location Code, given the reference location
/// </returns>
/// <param name="referenceLatitude">The reference latitude in decimal degrees.</param>
/// <param name="referenceLongitude">The reference longitude in decimal degrees.</param>
public OpenLocationCode Recover(double referenceLatitude, double referenceLongitude)
{
if (IsFull())
{
// Note: each code is either full xor short, no other option.
return(this);
}
referenceLatitude = ClipLatitude(referenceLatitude);
referenceLongitude = NormalizeLongitude(referenceLongitude);
int digitsToRecover = SeparatorPosition - Code.IndexOf(Separator);
// The precision (height and width) of the missing prefix in degrees.
double prefixPrecision = Math.Pow(EncodingBase, 2 - (digitsToRecover / 2));
// Use the reference location to generate the prefix.
string recoveredPrefix =
new OpenLocationCode(referenceLatitude, referenceLongitude).Code.Substring(0, digitsToRecover);
// Combine the prefix with the short code and decode it.
OpenLocationCode recovered = new OpenLocationCode(recoveredPrefix + Code);
CodeArea recoveredCodeArea = recovered.Decode();
// Work out whether the new code area is too far from the reference location. If it is, we
// move it. It can only be out by a single precision step.
double recoveredLatitude = recoveredCodeArea.CenterLatitude;
double recoveredLongitude = recoveredCodeArea.CenterLongitude;
// Move the recovered latitude by one precision up or down if it is too far from the reference,
// unless doing so would lead to an invalid latitude.
double latitudeDiff = recoveredLatitude - referenceLatitude;
if (latitudeDiff > prefixPrecision / 2 && recoveredLatitude - prefixPrecision > -LatitudeMax)
{
recoveredLatitude -= prefixPrecision;
}
else if (latitudeDiff < -prefixPrecision / 2 && recoveredLatitude + prefixPrecision < LatitudeMax)
{
recoveredLatitude += prefixPrecision;
}
// Move the recovered longitude by one precision up or down if it is too far from the
// reference.
double longitudeDiff = recoveredCodeArea.CenterLongitude - referenceLongitude;
if (longitudeDiff > prefixPrecision / 2)
{
recoveredLongitude -= prefixPrecision;
}
else if (longitudeDiff < -prefixPrecision / 2)
{
recoveredLongitude += prefixPrecision;
}
return(new OpenLocationCode(recoveredLatitude, recoveredLongitude, recovered.Code.Length - 1));
}
private static OpenLocationCode RecoverNearestValid(string shortCode, double referenceLatitude, double referenceLongitude)
{
referenceLatitude = ClipLatitude(referenceLatitude);
referenceLongitude = NormalizeLongitude(referenceLongitude);
int digitsToRecover = SeparatorPosition - shortCode.IndexOf(SeparatorCharacter);
// The precision (height and width) of the missing prefix in degrees.
double prefixPrecision = Math.Pow(EncodingBase, 2 - (digitsToRecover / 2));
// Use the reference location to generate the prefix.
string recoveredPrefix =
new OpenLocationCode(referenceLatitude, referenceLongitude).Code.Substring(0, digitsToRecover);
// Combine the prefix with the short code and decode it.
OpenLocationCode recovered = new OpenLocationCode(recoveredPrefix + shortCode);
GeoPoint recoveredCodeAreaCenter = recovered.Decode().Center;
// Work out whether the new code area is too far from the reference location. If it is, we
// move it. It can only be out by a single precision step.
double recoveredLatitude = recoveredCodeAreaCenter.Latitude;
double recoveredLongitude = recoveredCodeAreaCenter.Longitude;
// Move the recovered latitude by one precision up or down if it is too far from the reference,
// unless doing so would lead to an invalid latitude.
double latitudeDiff = recoveredLatitude - referenceLatitude;
if (latitudeDiff > prefixPrecision / 2 && recoveredLatitude - prefixPrecision > -LatitudeMax)
{
recoveredLatitude -= prefixPrecision;
}
else if (latitudeDiff < -prefixPrecision / 2 && recoveredLatitude + prefixPrecision < LatitudeMax)
{
recoveredLatitude += prefixPrecision;
}
// Move the recovered longitude by one precision up or down if it is too far from the reference.
double longitudeDiff = recoveredCodeAreaCenter.Longitude - referenceLongitude;
if (longitudeDiff > prefixPrecision / 2)
{
recoveredLongitude -= prefixPrecision;
}
else if (longitudeDiff < -prefixPrecision / 2)
{
recoveredLongitude += prefixPrecision;
}
return(new OpenLocationCode(recoveredLatitude, recoveredLongitude, recovered.CodeDigits.Length));
}