Calculation of new variables needed for Non-id HBT added. (Z. Chajecki)

[u/mrichter/AliRoot.git] / STEER / AliTrackReference.cxx

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 * Author: The ALICE Off-line Project.                                    *
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 * documentation strictly for non-commercial purposes is hereby granted   *
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/* $Id$ */

#include "TLorentzVector.h"
#include "TVirtualMC.h"

#include "AliRun.h"
#include "AliTrackReference.h"

// 
// Track Reference object is created every time particle is 
// crossing detector bounds. The object is created by Step Manager
//
// The class stores the following informations:
// track label, 
// track position: X,Y,X
// track momentum px, py, pz
// track length and time of fligth: both in cm
// status bits from Monte Carlo
//


ClassImp(AliTrackReference)

//_______________________________________________________________________
 AliTrackReference::AliTrackReference():
   fTrack(0),
   fX(0),
   fY(0),
   fZ(0),
   fPx(0),
   fPy(0),
   fPz(0),
   fLength(0)
{
  //
  // Default constructor
  // Creates empty object

  for(Int_t i=0; i<16; i++) ResetBit(BIT(i));
}

//_______________________________________________________________________
AliTrackReference::AliTrackReference(Int_t label) {
  //
  // Create Reference object out of label and
  // data in TVirtualMC object
  //
  // Creates an object and fill all parameters 
  // from data in VirtualMC
  //
  // Sylwester Radomski, (S.Radomski@gsi.de)
  // GSI, Jan 31, 2003
  //
    
  TLorentzVector vec;
  
  fTrack = label;
  fLength = gMC->TrackLength();
  fTime = gMC->TrackTime();

  gMC->TrackPosition(vec);

  fX = vec[0];
  fY = vec[1];
  fZ = vec[2];
  
  gMC->TrackMomentum(vec);
  
  fPx = vec[0];
  fPy = vec[1];
  fPz = vec[2];

  // Set Up status code 
  // Copy Bits from virtual MC

  for(Int_t i=0; i<16; i++) ResetBit(BIT(i));

  SetBit(BIT(0), gMC->IsNewTrack());
  SetBit(BIT(1), gMC->IsTrackAlive());
  SetBit(BIT(2), gMC->IsTrackDisappeared());
  SetBit(BIT(3), gMC->IsTrackEntering());
  SetBit(BIT(4), gMC->IsTrackExiting());
  SetBit(BIT(5), gMC->IsTrackInside());
  SetBit(BIT(6), gMC->IsTrackOut());
  SetBit(BIT(7), gMC->IsTrackStop()); 
}
//_______________________________________________________________________