/// <summary>
/// Gets the elevation from this location to another location (positive = up).
/// </summary>
/// <param name="from">This starting point location.</param>
/// <param name="to">The destination location.</param>
/// <returns>The distance vector between the two locations.</returns>
public static double ElevationTo(this ILocation from, ILocation to)
{
if (from == null)
{
throw new ArgumentNullException(nameof(from), "The from location is null");
}
if (to == null)
{
throw new ArgumentNullException(nameof(to), "The to location is null");
}
return(from.ElevationTo(to, from.HaversineDistanceTo(to)));
}
/// <summary>
/// Gets the direction from this location to another location.
/// </summary>
/// <param name="from">This starting point location.</param>
/// <param name="to">The destination location.</param>
/// <returns>The distance vector between the two locations.</returns>
public static IDirectionVector DirectionTo(this ILocation from, ILocation to)
{
if (from == null)
{
throw new ArgumentNullException(nameof(from), "The from location is null");
}
if (to == null)
{
throw new ArgumentNullException(nameof(to), "The to location is null");
}
// computing distance only once and passing it to elevation to optimize performance
var distance = from.HaversineDistanceTo(to);
return(new DirectionVector(
from,
to,
distance,
from.GreatCircleBearingTo(to),
from.ElevationTo(to, distance)));
}