/// <summary>
/// Calculate the distance between 2 points along the surface of the earth using the haversine formula
/// </summary>
public static ArcDistance Distance(GeoPoint a, GeoPoint b)
{
a = a.ToRadians();
b = b.ToRadians();
double u = Math.Sin((b.Latitude - a.Latitude) / 2);
double v = Math.Sin((b.Longitude - a.Longitude) / 2);
var radians = 2.0 * Math.Asin(Math.Sqrt(u * u + Math.Cos(b.Latitude) * Math.Cos(a.Latitude) * v * v));
return new ArcDistance(radians);
}
public NamedGeoPoint(string name, GeoPoint point)
{
Name = name;
Point = point;
}
public Entry(double lat, double lon)
{
Point = new GeoPoint(lat, lon);
}
public Entry(T item, GeoPoint point)
{
Point = point;
Item = item;
}
/// <summary>
/// The distance to a point, see Distance
/// </summary>
/// <param name="other"></param>
public ArcDistance DistanceTo(GeoPoint other)
{
return Distance(this, other);
}