CbmKFTrackInterface.h

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/** Abstract base class for track is being used by the CbmKF Kalman Filter
 *
 * @author  S.Gorbunov
 * @version 0.0
 * @since   02.12.05
 *
 * The class members describes to the CbmKF Kalman Filter routines
 * how to get acces to data in a derived (or user) class.
 *
 * To be used by high-level utilites like StsTrackFitter
 *
 * IMPORTANT : you should keep your hits sorted downstream
 *
 * See how-to-use-it below.
 */
#ifndef CBMKFTRACKINTERFACE_H
#define CBMKFTRACKINTERFACE_H
 
#include "TObject.h"
 
class CbmKFHit;
class CbmKFVertexInterface;
 
class CbmKFTrackInterface
{
 
  public:
    CbmKFTrackInterface()
        : fId()
    {}
    virtual ~CbmKFTrackInterface() {}
 
    /** Information not to be changed
     */
 
    virtual Double_t GetMass() { return 0.1396; }   /// Mass hypothesis
    virtual Bool_t IsElectron() { return 0; }       /// Is it electron
 
    /** I/O parameters for extrapolation routines
     */
 
    virtual Double_t* GetTrack();       /// array[6] of track parameters(x,y,tx,ty,qp,z)
    virtual Double_t* GetCovMatrix();   /// array[15] of covariance matrix
 
    /** Parameters during and after the track fit
     */
 
    virtual Double_t& GetRefChi2();   /// Chi^2 after fit
    virtual Int_t& GetRefNDF();       /// Number of Degrees of Freedom after fit
 
    /** Accessors to the track hits during track fit
     */
 
    virtual Int_t GetNOfHits() { return 0; }          /// Number of hits
    virtual CbmKFHit* GetHit(Int_t i) { return 0; }   /// Access to i-th hit
 
    /** Methods
     */
    Int_t Extrapolate(Double_t z, Double_t* QP0 = 0, Bool_t line = false);
    Int_t Fit(Bool_t downstream = 1, Bool_t line = false);
    void Smooth(Double_t Z);
    void Fit2Vertex(CbmKFVertexInterface& vtx);
 
    Int_t Propagate(Double_t z_out, Double_t QP0, Bool_t line = false);
    Int_t Propagate(Double_t z_out, Bool_t line = false);
 
    int Id() const { return fId; };
    void SetId(int id) { fId = id; };
    void SetTrkID(int id) { ststrk = id; };
    int GetTrkID() { return ststrk; };
 
  protected:
    int fId;
 
  private:
    int ststrk;
 
    ClassDef(CbmKFTrackInterface, 1)
};
 
/******************************************************************
 *
 *  There are few ways to let the Kalman Filter treat your track.
 *
 ******************************************************************
 *
 * // The first way: inherit the CbmKFTrackInterface, like :
 *
 * class CbmMyTrack :public CbmKFTrackInterface{
 *  public:
 *   // here overwrite CbmKF virtual methods
 *   Double_t *GetTrack(){ return fT; }
 *   ...
 *   // Here is my methods
 *   ...
 *  private:
 *   Double_t fT[6];
 *   Double_t fVariablesForMyNeeds;
 * };
 *
 * // Then use your track directly:
 *
 * CbmMyTrack my_track;
 * ...
 * CbmKF::Instance()->FitTrack( my_track );
 *
 *
 ******************************************************************
 *
 *
 * // The second way: make interface class to your track, like:
 *
 * class CbmMyTrack{
 *  public:
 *   Double_t *GetFittedTrackParametersAtThePrimaryVertex();
 *   ...
 * };
 *
 * class CbmMyTrackInterface : public CbmKFTrackInterface{
 *  public:
 *   CbmMyTrackInterface( CbmMyTrack *track ):fTrack(track){}
 *   Double_t *GetTrack(){
 *     return ((CbmMyTrack*)fTrack)->GetFittedTrackParametersAtThePrimaryVertex();
 *   }
 *   ...
 *  private:
 *   CbmMyTrackTrack *fTrack;
 * };
 *
 * // Then call the KF routines through the interface, like:
 *
 * CbmMyTrack my_track;
 * ...
 * CbmMyTrackInterface I(my_track);
 * CbmKF::Instance()->FitTrack( I );
 *
 ******************************************************************
 *
 *
 * // Other ways...
 *
 *
 */
 
#endif /* !CBMKFTRACKINTERFACE_H */