/// <summary>Creates a new instance using the specified end points.</summary>
public Segment(Position start, Position end)
{
_Start = start;
_End = end;
}
/// <summary>
/// Returns the distance from the segment to the specified position.
/// </summary>
/// <param name="position"></param>
/// <returns></returns>
/// <remarks>This method analyzes the relative position of the segment to the line to determine the
/// best mathematical approach.</remarks>
public Distance DistanceTo(Position position)
{
if(_Start.Equals(_End))
return position.DistanceTo(_Start);
Position Delta = _End.Subtract(_Start);
double Ratio = ((position.Longitude.DecimalDegrees - _Start.Longitude.DecimalDegrees)
* Delta.Longitude.DecimalDegrees + (position.Latitude.DecimalDegrees - _Start.Latitude.DecimalDegrees)
* Delta.Latitude.DecimalDegrees) / (Delta.Longitude.DecimalDegrees * Delta.Longitude.DecimalDegrees + Delta.Latitude.DecimalDegrees
* Delta.Latitude.DecimalDegrees);
if(Ratio < 0)
return position.DistanceTo(_Start);
else if(Ratio > 1)
return position.DistanceTo(_End);
else
{
Position Destination = new Position(
new Latitude((1 - Ratio) * _Start.Latitude.DecimalDegrees + Ratio * _End.Latitude.DecimalDegrees),
new Longitude((1 - Ratio) * _Start.Longitude.DecimalDegrees + Ratio * _End.Longitude.DecimalDegrees));
return position.DistanceTo(Destination);
}
}
