/// <summary>
/// TierBoxId is latitude box id + longitude box id
/// where latitude box id, and longitude box id are transposed in to position
/// coordinates.
/// </summary>
/// <param name="latitude">The latitude.</param>
/// <param name="longitude">The longitude.</param>
/// <returns></returns>
public double GetTierBoxId(double latitude, double longitude)
{
double[] coords = _projector.Coords(latitude, longitude);
double id = GetBoxId(coords[0]) + (GetBoxId(coords[1]) / TierVerticalPosDivider);
return(id);
}