TrajectoryStateClosestToPoint.h

Go to the documentation of this file.

#ifndef TrajectoryStateClosestToPoint_H
#define TrajectoryStateClosestToPoint_H
 
#include "TrackingTools/TrajectoryState/interface/TrajectoryStateOnSurface.h"
#include "TrackingTools/TrajectoryState/interface/FreeTrajectoryState.h"
#include "TrackingTools/TrajectoryParametrization/interface/PerigeeTrajectoryParameters.h"
#include "TrackingTools/TrajectoryParametrization/interface/PerigeeTrajectoryError.h"
#include "TrackingTools/TrajectoryState/interface/PerigeeConversions.h"
 
class TrajectoryStateClosestToPoint {
  typedef TrajectoryStateOnSurface TSOS;
  typedef FreeTrajectoryState FTS;
 
public:
  TrajectoryStateClosestToPoint() : valid(false), theFTSavailable(false), errorIsAvailable(false) {}
 
  TrajectoryStateClosestToPoint(const PerigeeTrajectoryParameters& perigeeParameters,
                                double pt,
                                const GlobalPoint& referencePoint,
                                const MagneticField* field)
      : theField(field),
        theRefPoint(referencePoint),
        theParameters(perigeeParameters),
        thePt(pt),
        valid(true),
        theFTSavailable(false),
        errorIsAvailable(false) {}
 
  TrajectoryStateClosestToPoint(const PerigeeTrajectoryParameters& perigeeParameters,
                                double pt,
                                const PerigeeTrajectoryError& perigeeError,
                                const GlobalPoint& referencePoint,
                                const MagneticField* field)
      : theField(field),
        theRefPoint(referencePoint),
        theParameters(perigeeParameters),
        thePt(pt),
        thePerigeeError(perigeeError),
        valid(true),
        theFTSavailable(false),
        errorIsAvailable(true) {}
 
  const GlobalPoint& referencePoint() const { return theRefPoint; }
 
  const PerigeeTrajectoryParameters& perigeeParameters() const { return theParameters; }
 
  double pt() const { return thePt; }
 
  const PerigeeTrajectoryError& perigeeError() const { return thePerigeeError; }
 
  GlobalPoint position() const { return PerigeeConversions::positionFromPerigee(theParameters, theRefPoint); }
 
  GlobalVector momentum() const { return PerigeeConversions::momentumFromPerigee(theParameters, thePt, theRefPoint); }
 
  TrackCharge charge() const { return theParameters.charge(); }
 
  const FreeTrajectoryState& theState() const {
    if (!theFTSavailable)
      calculateFTS();
    return theFTS;
  }
 
  bool hasError() const { return errorIsAvailable; }
 
  bool isValid() const { return valid; }
 
  friend class TrajectoryStateClosestToPointBuilder;
 
  TrajectoryStateClosestToPoint(const FTS& originalFTS, const GlobalPoint& referencePoint);
 
  void calculateFTS() const;
 
private:
  const MagneticField* theField;
 
  mutable FTS theFTS;
 
  GlobalPoint theRefPoint;
  PerigeeTrajectoryParameters theParameters;
  double thePt;
  PerigeeTrajectoryError thePerigeeError;
  bool valid;
  mutable bool theFTSavailable;
  bool errorIsAvailable;
};
#endif