int Line::intersect(std::list<Kernel::V3D> &PntOut, const Cylinder &Cyl) const
/**
For the line that intersects the cylinder generate
add the point to the VecOut, return number of points
added. It does not check the points for validity.
@param PntOut :: Vector of points found by the line/cylinder intersection
@param Cyl :: Cylinder to intersect line with
@return Number of points found by intersection
*/
{
const Kernel::V3D Cent = Cyl.getCentre();
const Kernel::V3D Ax = Origin - Cent;
const Kernel::V3D N = Cyl.getNormal();
const double R = Cyl.getRadius();
const double vDn = N.scalar_prod(Direct);
const double vDA = N.scalar_prod(Ax);
// First solve the equation of intersection
double C[3];
C[0] = 1.0 - (vDn * vDn);
C[1] = 2.0 * (Ax.scalar_prod(Direct) - vDA * vDn);
C[2] = Ax.scalar_prod(Ax) - (R * R + vDA * vDA);
std::pair<std::complex<double>, std::complex<double>> SQ;
const int ix = solveQuadratic(C, SQ);
// This takes the centre displacement into account:
return lambdaPair(ix, SQ, PntOut);
}
