Reconstruction/MdcPatRec/TrkBase/include/TrkBase/TrkSimpTraj.h

Go to the documentation of this file.

//--------------------------------------------------------------------------
// File and Version Information:
//      $Id: TrkSimpTraj.h,v 1.2 2006/03/28 01:02:36 zhangy Exp $
//
// Description:  TrkSimpTraj is an abstract class for trajectories that
//     contain a simple set of parameters (i.e. it's not a composite
//     trajectory).  It is a base class for things like HelixTraj and
//     LineTraj, and inherits from TrkDifTraj.  The reference point (what
//     the parameters implicitly use to relate to BaBar 3-space) is now
//     an explicit member, as opposed to being implicitly set to 0,0,0.
//
// Note: the HP compiler is too stupid to process the default ctor, so instead
// the origin will be hard-coded to 0,0,0 for the HP (only).  This could
// well cause problems for HP users someday, but complaints should be addressed
// to the manufacturer of those boxes, not me.
//
//
// Environment:
//      Software developed for the BaBar Detector at the SLAC B-Factory.
//
// Author(s): Steve Schaffner, Dave Brown
//
//------------------------------------------------------------------------
 
#ifndef TRKSIMPTRAJ_HH
#define TRKSIMPTRAJ_HH
 
#include "CLHEP/Geometry/Point3D.h"
#include "TrkBase/TrkDifTraj.h"
#include "TrkBase/TrkKalDeriv.h"
#include "TrkBase/TrkParams.h"
#ifndef ENABLE_BACKWARDS_COMPATIBILITY
typedef HepGeom::Point3D<double> HepPoint3D;
#endif
#include "CLHEP/Matrix/SymMatrix.h"
#include "CLHEP/Matrix/Vector.h"
 
#include <vector>
 
class TrkVisitor;
using CLHEP::HepSymMatrix;
using CLHEP::HepVector;
#include <iosfwd>
 
//  Prototype the point translation functions.  This is kind of ugly
typedef void ( *TranslateParams )( const HepPoint3D& oldpoint, const HepPoint3D& newpoint,
                                   const HepVector& oldpar, const HepSymMatrix& oldcov,
                                   HepVector& newpar, HepSymMatrix& newcov, double fltlen );
 
// Class interface //
class TrkSimpTraj : public TrkDifTraj, public TrkKalDeriv {
 
public:
  static HepPoint3D _theOrigin; // define the origin as a HepPoint3D
 
public:
  //-----------------------
  // Constructors and such
  //-----------------------
  TrkSimpTraj( const HepVector& params, const HepSymMatrix& cov,
               const double startRange = -99999., const double endRange = 99999.,
               const HepPoint3D& refpoint = _theOrigin );
  TrkSimpTraj( const TrkParams& params, const double startRange = -99999.,
               const double endRange = 99999., const HepPoint3D& refpoint = _theOrigin );
  virtual ~TrkSimpTraj();
 
  virtual TrkSimpTraj* clone() const = 0;
 
  //--------------------------------------------------
  //  Access to parameters, errors and reference point
  //--------------------------------------------------
  TrkParams*                 parameters() { return &_dtparams; }
  const TrkParams*           parameters() const { return &_dtparams; }
  virtual const TrkSimpTraj* localTrajectory( double fltLen, double& localFlt ) const;
  const HepPoint3D&          referencePoint() const { return _refpoint; }
  virtual void               print( std::ostream& os ) const;
  virtual void               printAll( std::ostream& os ) const;
  // yzhang
  virtual int nPar() const { return parameters()->nPar(); }
  // zhangy
  //--------------------------------------------------
  //  Change contents
  //--------------------------------------------------
  //  Change the reference point and the parameters
  void changePoint( const HepPoint3D& newpoint, double& fltlen );
  // Set the ref point and don't change the params
  void setPoint( const HepPoint3D& newpoint ) { _refpoint = newpoint; }
  // inversion function: this inverts both the flight range and the parameters
  // so that the same traj is described but going in the opposite direction.
  TrkSimpTraj& invert();
  // invert the track parameters passed in newparams.
  // Returns true in flags if the inversion requires a sign change in the
  // covariance matrix as well.
  virtual void invertParams( TrkParams* newparams, std::vector<bool>& flags ) const = 0;
  // Provide function which translates the reference point of parameters
  virtual TranslateParams paramFunction() const = 0;
 
  //--------------------------------------------------
  // Visitor access for momentum functions
  //--------------------------------------------------
 
  virtual void visitAccept( TrkVisitor* vis ) const = 0;
 
  bool operator==( const TrkSimpTraj& ) const; // return equivalence, not identy
 
protected:
  TrkParams  _dtparams;
  HepPoint3D _refpoint; // reference point for parameters
private:
  // Preempt
  TrkSimpTraj( const TrkSimpTraj& );
  TrkSimpTraj& operator=( const TrkSimpTraj& );
};
#endif