/// <summary>
/// Get a rectangle which contains a path along the given line 'pathWidth' wide
/// </summary>
/// <param name="pathWidth"></param>
/// <returns></returns>
public RectangleD GetPathRectangle(Double pathWidth, Double extend)
{
PointD p1 = ((PointD)P1).GetPointAt(Bearing.AddDegrees(90), pathWidth / 2) as PointD;
PointD p2 = ((PointD)P1).GetPointAt(Bearing.SubtractDegrees(90), pathWidth / 2) as PointD;
PointD p3 = ((PointD)P2).GetPointAt(Bearing.SubtractDegrees(90), pathWidth / 2) as PointD;
PointD p4 = ((PointD)P2).GetPointAt(Bearing.AddDegrees(90), pathWidth / 2) as PointD;
if (extend > 0)
{
p1 = p1.GetPointAt(Bearing.AddDegrees(180), extend) as PointD;
p2 = p2.GetPointAt(Bearing.AddDegrees(180), extend) as PointD;
p3 = p3.GetPointAt(Bearing, extend) as PointD;
p4 = p4.GetPointAt(Bearing, extend) as PointD;
}
return(new RectangleD(p1, p2, p3, p4));
}