/// <summary>
/// This method calculates the distance to a point Pt.
/// The parameter Lam can be used to calculate the nearest point of the LineType, which is
/// also returned by the outvalue Nearest
/// </summary>
/// <param name="Pt">Point to calculate the distance to the LineType</param>
/// <param name="Lam">Parameter to calculate the nearest point</param>
/// <param name="Nearest">Point on the Line, with the lowest distance to Pt</param>
/// <returns>Returns the distance from the line to the point Pt</returns>
public double Distance(xyz Pt, out double Lam, out xyz Nearest)
{
if (Utils.Equals(Direction.length(), 0))
{
Lam = 0;
Nearest = P;
return(Pt.dist(P));
}
Lam = Direction.normalized().Scalarproduct(Pt.sub(P)) / Direction.length();
Nearest = P.add(Direction.mul(Lam));
return(Nearest.dist(Pt));
}
/// <summary>
/// The base will be transformed by the Matrix m.
/// </summary>
/// <param name="m">m holds the transform matrix which will be applied to the base</param>
/// <returns></returns>
public Base mul(Matrix m)
{
Base result = new Base();
result.BaseO = BaseO.mul(m);
xyz InHomogen = m * new xyz(0, 0, 0);
result.BaseX = BaseX.mul(m) - InHomogen;
result.BaseY = BaseY.mul(m) - InHomogen;
result.BaseZ = BaseZ.mul(m) - InHomogen;
return(result);
}
/// <summary>
/// This method calculates the distance to a Line L
/// The parameter Lam1 can be taken to calculate the point, which has the lowest distance to
/// the other Line L . Nearest1 = Value(Lam1).
/// The parameter Lam2 can be taken to calculate the point of L , which has the lowest distance to
/// the Linetype this. Nearest2 = L.Value(Lam2).
/// </summary>
/// <param name="L">The other LineType</param>
/// <param name="Lam1">Paramter which belongs to this line : Nearest1 = Value(Lam1)</param>
/// <param name="Lam2">Paramter which belongs to the Line L: Nearest2 = L.Value(Lam2)</param>
/// <param name="Nearest1">The point on the Line, which has the smallest distance to the Line L</param>
/// <param name="Nearest2">The point on the Line L, which has the smallest distance </param>
/// <returns>Returns the distance to the line L</returns>
public double Distance(LineType L, out double Lam1, out double Lam2, out xyz Nearest1, out xyz Nearest2)
{
xyz PQ = L.P.sub(P);
double PQV = PQ.Scalarproduct(Direction);
double PQW = PQ.Scalarproduct(L.Direction);
double vv = Direction.Scalarproduct(Direction);
double ww = L.Direction.Scalarproduct(L.Direction);
double vw = L.Direction.Scalarproduct(Direction);
double Det = vv * ww - vw * vw;
if (Det == 0)// parallele
{
xyz n = PQ.cross(Direction).cross(Direction).normalized();
double result = PQ.Scalarproduct(n);
Nearest2 = P.add(n.mul(result));
Nearest1 = P;
Lam1 = 0;
Lam2 = L.Direction.normalized().Scalarproduct(Nearest2.sub(L.P));
return(System.Math.Abs(result));
}
else
{
Lam1 = (PQV * ww - PQW * vw) / Det;
Lam2 = -(PQW * vv - PQV * vw) / Det;
Nearest1 = P.add(Direction.mul(Lam1));
Nearest2 = L.P.add(L.Direction.mul(Lam2));
return(Nearest1.dist(Nearest2));
}
}
/// <summary>
/// Calculate the cross point with a line.
/// </summary>
/// <param name="aLine">A line which intersects the plane</param>
/// <param name="Lam">Is a parameter, which determines the crosspoint</param>
/// <param name="pt">Is the cross point</param>
/// <returns>returns true, if there is a crosspoint.</returns>
/// <example><code>
/// //the following snippet shows the meaning of lam
/// Plane p = new Plane( new xyz(0, 0, 0), new xyz(1, 5, 5));
/// LineType l = new LineType( new xyz (3,-1,3), new xyz(2, 1, 5));
/// if (p.Cross(l, out Lam, out pt))
/// {
/// // you can also get p through the following
/// pt = l.P + l.Direction*lam;
/// }
/// </code></example>
public bool Cross(LineType aLine, out double Lam, out xyz pt)
{
pt = aLine.P;
Lam = -1;
xyz Direction = aLine.Direction.normalized();
double En = Direction.Scalarproduct(NormalUnit);
if (System.Math.Abs(En) < Utils.epsilon)
{
return(false);
}
xyz OP = aLine.P;
OP = OP.sub(P);
Lam = -OP.Scalarproduct(NormalUnit) / En;
pt = pt.add(Direction.mul(Lam));
Lam /= (aLine.P - aLine.Q).length();
return(true);
}