Trk::TrackStateOnSurfaceComparisonFunction Class Reference

Class providing comparison function, or relational definition, for sorting MeasurementBase objects. More...

#include <TrackStateOnSurfaceComparisonFunction.h>

Collaboration diagram for Trk::TrackStateOnSurfaceComparisonFunction:

Public Member Functions
	TrackStateOnSurfaceComparisonFunction (double cradius)
	Default Constructor, using a given radius.
	TrackStateOnSurfaceComparisonFunction (const Amg::Vector3D &dir)
	Simple relation definition using a 3d distance to the reference point.
	TrackStateOnSurfaceComparisonFunction (const Amg::Vector3D &sp, const Amg::Vector3D &dir)
	Full relation definition using a straight line propagation.
bool	operator() (const Trk::TrackStateOnSurface *one, const Trk::TrackStateOnSurface *two) const
	The comparison function defining in what case a PRD is 'smaller' than a second one.

Private Types
enum	ComparisonMode {   RADIAL_TO_ZERO , TO_GIVEN_RADIUS , DIRECTIONAL_TO_ZERO , DIRECTIONAL_TO_POINT ,   NMODES }

Private Member Functions
double	calculateAppropriatePath (const Trk::Surface *pSurface, const Amg::Vector3D gp) const
double	pathIntersectWithPlane (const Trk::PlaneSurface *psf) const
double	pathIntersectWithLine (const Trk::StraightLineSurface *lsf) const
double	pathIntersectWithLine (const Trk::PerigeeSurface *pgsf) const
double	pathIntersectWithDisc (const Trk::DiscSurface *dsf) const
double	pathIntersectWithCylinder (const Trk::CylinderSurface *csf, const Amg::Vector3D &globalHit) const

Private Attributes
const Amg::Vector3D	m_point {0.,0.,0.}
const Amg::Vector3D	m_direction {0.,0.,0.}
const double	m_radius {0.}
const ComparisonMode	m_mode {RADIAL_TO_ZERO}

Detailed Description

Class providing comparison function, or relational definition, for sorting MeasurementBase objects.

Definition at line 37 of file TrackStateOnSurfaceComparisonFunction.h.

Member Enumeration Documentation

ComparisonMode

enum Trk::TrackStateOnSurfaceComparisonFunction::ComparisonMode

private

Enumerator
RADIAL_TO_ZERO
TO_GIVEN_RADIUS
DIRECTIONAL_TO_ZERO
DIRECTIONAL_TO_POINT
NMODES

Definition at line 110 of file TrackStateOnSurfaceComparisonFunction.h.

                       {RADIAL_TO_ZERO, TO_GIVEN_RADIUS, 
      DIRECTIONAL_TO_ZERO, DIRECTIONAL_TO_POINT, NMODES};

Constructor & Destructor Documentation

TrackStateOnSurfaceComparisonFunction() [1/3]

Trk::TrackStateOnSurfaceComparisonFunction::TrackStateOnSurfaceComparisonFunction ( double cradius )

inline

Default Constructor, using a given radius.

Definition at line 41 of file TrackStateOnSurfaceComparisonFunction.h.

      : m_radius(std::abs(cradius)),
        m_mode{TO_GIVEN_RADIUS}
          {}

TrackStateOnSurfaceComparisonFunction() [2/3]

Trk::TrackStateOnSurfaceComparisonFunction::TrackStateOnSurfaceComparisonFunction ( const Amg::Vector3D & dir )

inline

Simple relation definition using a 3d distance to the reference point.

Definition at line 47 of file TrackStateOnSurfaceComparisonFunction.h.

      : m_direction(dir.unit()), m_mode{DIRECTIONAL_TO_ZERO}
          {}

TrackStateOnSurfaceComparisonFunction() [3/3]

Trk::TrackStateOnSurfaceComparisonFunction::TrackStateOnSurfaceComparisonFunction ( const Amg::Vector3D & sp, const Amg::Vector3D & dir )

inline

Full relation definition using a straight line propagation.

Definition at line 52 of file TrackStateOnSurfaceComparisonFunction.h.

      : m_point(sp), m_direction(dir.unit()), m_mode{DIRECTIONAL_TO_POINT}
      {}

Member Function Documentation

calculateAppropriatePath()

double Trk::TrackStateOnSurfaceComparisonFunction::calculateAppropriatePath ( const Trk::Surface * pSurface, const Amg::Vector3D gp ) const

inlineprivate

Definition at line 118 of file TrackStateOnSurfaceComparisonFunction.h.

                                                                                     {
      double path{0.};
      switch (pSurface->type()){
        case Trk::SurfaceType::Plane:
          path = pathIntersectWithPlane(static_cast <const Trk::PlaneSurface*>(pSurface));
          break;
        case  Trk::SurfaceType::Line:
          path = pathIntersectWithLine(static_cast <const  Trk::StraightLineSurface*>(pSurface));
          break;
        case Trk::SurfaceType::Disc:
          path = pathIntersectWithDisc(static_cast <const  Trk::DiscSurface*>(pSurface));
          break;
        case Trk::SurfaceType::Cylinder:
          path = pathIntersectWithCylinder(static_cast <const  Trk::CylinderSurface*>(pSurface), gp);
          break;
        case Trk::SurfaceType::Perigee:
          path = pathIntersectWithLine(static_cast <const  Trk::PerigeeSurface*>(pSurface));
          break;
        default:
          std::cout << "TrackStateOnSurfaceComparisonFunction: surface type error" << std::endl;
      }
      return path;
    }

operator()()

bool Trk::TrackStateOnSurfaceComparisonFunction::operator() ( const Trk::TrackStateOnSurface * one, const Trk::TrackStateOnSurface * two ) const

inline

The comparison function defining in what case a PRD is 'smaller' than a second one.

Definition at line 61 of file TrackStateOnSurfaceComparisonFunction.h.

                                                                                            {
      Amg::Vector3D gp1;
      Amg::Vector3D gp2;
      gp1.setZero();
      gp2.setZero();
      const Trk::Surface*  surf1 = 0;
      const Trk::Surface*  surf2 = 0;
      if ( ! ( one->trackParameters() || one->measurementOnTrack() ) ){
        std::cout << "TrackStateOnSurfaceComparisonFunction: input TSOS one not sufficient" << std::endl;
        return true;
      }
      if ( ! ( two->trackParameters() || two->measurementOnTrack() ) ){
        std::cout << "TrackStateOnSurfaceComparisonFunction: input TSOS two not sufficient" << std::endl;
        return false;
      }
      if (one->trackParameters()){
        gp1 = one->trackParameters()->position();
        surf1 = &one->trackParameters()->associatedSurface();   
        if (!surf1 && one->measurementOnTrack() ) surf1 = &(one->measurementOnTrack()->associatedSurface());    
      } else if (one->measurementOnTrack()){
        gp1 = one->measurementOnTrack()->globalPosition();
        surf1 = &(one->measurementOnTrack()->associatedSurface());    
      }
      if (two->trackParameters()){
        gp2 = two->trackParameters()->position();
        surf2 = &two->trackParameters()->associatedSurface();   
        if (!surf2 && two->measurementOnTrack() ) surf2 = &(two->measurementOnTrack()->associatedSurface());    
      } else if (two->measurementOnTrack()) {
        gp2 = two->measurementOnTrack()->globalPosition();
        surf2 = &(two->measurementOnTrack()->associatedSurface());    
      }
      // --- very simple case, check radial distances
      if (m_mode == RADIAL_TO_ZERO) {
        return ( std::abs(gp1.perp() - m_radius)< std::abs(gp2.perp() - m_radius) );
      }
      // --- simple case, just use global position distances
      else if (m_mode == TO_GIVEN_RADIUS) {
        return ( (gp1 - m_point).mag() < (gp2 - m_point).mag());
      } else {// --- flexible sorting along a predicted direction
        if ( ! ( surf1 && surf2 ) ){
          std::cout << "TrackStateOnSurfaceComparisonFunction: surface missing" << std::endl;
          return false;
        }
        double path1 = calculateAppropriatePath(surf1, gp1); //note: only cylinder needs
        double path2 = calculateAppropriatePath(surf2, gp2); //the second param.
        return path1 < path2;
      }
    }

pathIntersectWithCylinder()

double Trk::TrackStateOnSurfaceComparisonFunction::pathIntersectWithCylinder ( const Trk::CylinderSurface * csf, const Amg::Vector3D & globalHit ) const

inlineprivate

Definition at line 180 of file TrackStateOnSurfaceComparisonFunction.h.

                                                                  { 
      // --- code from TrkExSlPropagator/LineCylinderIntersection.cxx
      // get the rotation by reference
      const Amg::Transform3D& locTrans = csf->transform();
      // take two points of line and calculate them to the 3D frame of the cylinder
      Amg::Vector3D point1(locTrans.inverse() * m_point);
      Amg::Vector3D point2raw = m_point + m_direction;
      Amg::Vector3D point2(locTrans.inverse() * point2raw); // do it in two steps - CLHEP stability
      // new direction in 3D frame of cylinder
      Amg::Vector3D direc((point2 - point1).unit());
      if (!direc.x()){
        return 0.;
      } else {
        // get line and circle constants
        double k = (direc.y())/(direc.x());
        double d = (point2.x()*point1.y() - point1.x()*point2.y())/(point2.x() - point1.x());
        double R = csf->bounds().r();
        double first = 0.;
        double second= 0.;
    
        // and solve the quadratic equation  Trk::RealQuadraticEquation pquad(1+k*k, 2*k*d, d*d-R*R);
        double a = 1 + k*k;
        double p = 2*k*d;
        double q = d*d - R*R;
        double discriminant = p*p - 4*a*q;
        if (discriminant<0) {
          return 0.;
        } else {
          //          solutions = (discriminant==0) ? one : two;
          double x0 = -0.5*(p + (p>0 ? std::sqrt(discriminant) : -std::sqrt(discriminant)));
          first = x0/a;
          second = q/x0;
        }
        double t1 = (first  - point1.x())/direc.x();
        double t2 = (second - point1.x())/direc.x();
        // the solutions in the 3D frame of the cylinder
        Amg::Vector3D dist1raw(point1 + t1 * direc - globalHit);
        Amg::Vector3D dist2raw(point1 + t2 * direc - globalHit);
        // return the solution which is closer to Meas'Base's global coordinates
        if ( dist1raw.mag() < dist2raw.mag() ) {
          return t1; // FIXME - wrong line parameterisation
        } else {
          return t2;
        }
      }
    }

pathIntersectWithDisc()

double Trk::TrackStateOnSurfaceComparisonFunction::pathIntersectWithDisc ( const Trk::DiscSurface * dsf ) const

inlineprivate

Definition at line 173 of file TrackStateOnSurfaceComparisonFunction.h.

                                                          {
      double denom = m_direction.dot(dsf->normal());
      return denom ? dsf->normal().dot(dsf->center() - m_point)/denom :
        denom;
    }

pathIntersectWithLine() [1/2]

double Trk::TrackStateOnSurfaceComparisonFunction::pathIntersectWithLine ( const Trk::PerigeeSurface * pgsf ) const

inlineprivate

Definition at line 163 of file TrackStateOnSurfaceComparisonFunction.h.

                                                              {
      Amg::Vector3D trackToWire(pgsf->center() - m_point);
      double     parallelity = m_direction.dot(Trk::s_zAxis);
      double     denom       = 1 - parallelity*parallelity;
      return (std::abs(denom)>10e-7) ?
        (trackToWire.dot(m_direction)- trackToWire.dot(Trk::s_zAxis) * parallelity)/denom :
        0.;
    }

pathIntersectWithLine() [2/2]

double Trk::TrackStateOnSurfaceComparisonFunction::pathIntersectWithLine ( const Trk::StraightLineSurface * lsf ) const

inlineprivate

Definition at line 151 of file TrackStateOnSurfaceComparisonFunction.h.

                                                                  {
      Amg::Vector3D dirWire(lsf->transform().rotation().col(2).unit());
      Amg::Vector3D trackToWire(lsf->center() - m_point);
      double     parallelity = m_direction.dot(dirWire);
      double     denom       = 1 - parallelity*parallelity;
      return (std::abs(denom)>10e-7)                       ?
        (trackToWire.dot(m_direction) 
         - trackToWire.dot(dirWire)*parallelity)/denom :
        0.                                             ;
    }

pathIntersectWithPlane()

double Trk::TrackStateOnSurfaceComparisonFunction::pathIntersectWithPlane ( const Trk::PlaneSurface * psf ) const

inlineprivate

Definition at line 144 of file TrackStateOnSurfaceComparisonFunction.h.

                                                             {
      double denom = m_direction.dot(psf->normal()); // c++ can be unreadable
      return denom ?psf->normal().dot(psf->center() - m_point)/denom :
        denom                                            ;
    }

Member Data Documentation

m_direction

const Amg::Vector3D Trk::TrackStateOnSurfaceComparisonFunction::m_direction {0.,0.,0.}

private

Definition at line 113 of file TrackStateOnSurfaceComparisonFunction.h.

{0.,0.,0.};

m_mode

const ComparisonMode Trk::TrackStateOnSurfaceComparisonFunction::m_mode {RADIAL_TO_ZERO}

private

Definition at line 115 of file TrackStateOnSurfaceComparisonFunction.h.

{RADIAL_TO_ZERO};

m_point

const Amg::Vector3D Trk::TrackStateOnSurfaceComparisonFunction::m_point {0.,0.,0.}

private

Definition at line 112 of file TrackStateOnSurfaceComparisonFunction.h.

{0.,0.,0.};

m_radius

const double Trk::TrackStateOnSurfaceComparisonFunction::m_radius {0.}

private

Definition at line 114 of file TrackStateOnSurfaceComparisonFunction.h.

{0.};

---

The documentation for this class was generated from the following file:

• TrackStateOnSurfaceComparisonFunction.h