/// <summary>
/// Crosses the plane with an other plane and returns the crossline.
/// </summary>
/// <param name="aPlane">The other plane</param>
/// <returns></returns>
public LineType Cross(Plane aPlane)
{
LineType Result = new LineType();
xyz Dir = NormalUnit & aPlane.NormalUnit;
if (Dir.isZero())
{
return(Result);
}
xyz s = Dir & NormalUnit;
double Lam = (aPlane.P - P) * aPlane.NormalUnit / (s * aPlane.NormalUnit);
Result.P = P + s * Lam;
Result.Direction = Dir;
return(Result);
}