Added new data members to remove magic numbers

[u/mrichter/AliRoot.git] / EMCAL / AliEMCALGeometry.h

#ifndef ALIEMCALGEOMETRY_H
#define ALIEMCALGEOMETRY_H
/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 * See cxx source for full Copyright notice                               */

/* $Id$ */

//_________________________________________________________________________
// Geometry class  for EMCAL : singleton
// EMCAL consists of a layers of scintillator, and lead.
//                  
//*-- Author: Sahal Yacoob (LBL / UCT)
//*--   and : Yves Schutz (Subatech)

#include <assert.h> 

// --- ROOT system ---
#include "TString.h"
#include "TObjArray.h"
#include "TVector3.h"

// --- AliRoot header files ---

#include "AliGeometry.h"

class AliEMCALGeometry : public AliGeometry {
 public:
    AliEMCALGeometry() {
	// default ctor,  must be kept public for root persistency purposes,
	// but should never be called by the outside world
    };
    AliEMCALGeometry(const AliEMCALGeometry & geom) {
	// cpy ctor requested by Coding Convention but not yet needed
	assert(0==1);
    };
    virtual ~AliEMCALGeometry(void) ; 
    static AliEMCALGeometry * GetInstance(const Text_t* name,
					  const Text_t* title="") ; 
    static AliEMCALGeometry * GetInstance() ;
    AliEMCALGeometry & operator = (const AliEMCALGeometry  & rvalue) const {
	// assignement operator requested by coding convention but not needed
	assert(0==1) ;
	return *(GetInstance()) ; 
    };
    virtual void GetGlobal(const AliRecPoint *, TVector3 &, TMatrix &) const {}
    virtual void GetGlobal(const AliRecPoint *, TVector3 &) const {}
    // General
    Bool_t  IsInitialized(void) const { return fgInit ; }
    // Return EMCA geometrical parameters
    // geometry
    const Float_t GetAirGap() const { return fAirGap ; }
    const Float_t GetAlFrontThickness() const { return fAlFrontThick;}
    const Float_t GetArm1PhiMin() const { return fArm1PhiMin ; }
    const Float_t GetArm1PhiMax() const { return fArm1PhiMax ; }
    const Float_t GetArm1EtaMin() const { return fArm1EtaMin;}
    const Float_t GetArm1EtaMax() const { return fArm1EtaMax;}
    const Float_t GetIPDistance()   const { return  fIPDistance  ; } 
    const Float_t GetEnvelop(Int_t index) const { return fEnvelop[index] ; }  
    const Float_t GetShellThickness() const { return fShellThickness ; }
    const Float_t GetZLength() const { return fZLength ; } 
    const Float_t GetGap2Active() const {return  fGap2Active ; }
    const Float_t GetDeltaEta() const {return (fArm1EtaMax-fArm1EtaMin)/
					   ((Float_t)fNZ);}
    const Float_t GetDeltaPhi() const {return (fArm1PhiMax-fArm1PhiMin)/
					   ((Float_t)fNPhi);}
    const Int_t   GetNLayers() const {return fNLayers ;}
    const Int_t   GetNZ() const {return fNZ ;}
    const Int_t   GetNEta() const {return fNZ ;}
    const Int_t   GetNPhi() const {return fNPhi ;}
    const Float_t GetPbRadThick(){ // returns Pb radiator thickness in cm.
	return fPbRadThickness;
    }
    const Float_t GetFullSintThick(){ // returns Full tower sintilator
	                              // thickness in cm.
	return fFullShowerSintThick;
    }
    const Float_t GetPreSintThick(){ // returns PreShower tower sintilator
	                              // thickness in cm.
	return fPreShowerSintThick;
    }
    Float_t AngleFromEta(Float_t eta){ // returns angle in radians for a given
	// pseudorapidity.
	return 2.0*TMath::ATan(TMath::Exp(-eta));
	}
    Float_t ZFromEtaR(Float_t r,Float_t eta){ // returns z in for a given
	// pseudorapidity and r=sqrt(x*x+y*y).
	return r/TMath::Tan(AngleFromEta(eta));
	}
    Int_t TowerIndex(Int_t iz,Int_t iphi,Int_t ipre); // returns tower index
    // returns tower indexs iz, iphi.
    void TowerIndexes(Int_t index,Int_t &iz,Int_t &iphi,Int_t &ipre);
    // for a given tower index it returns eta and phi of center of that tower.
    void EtaPhiFromIndex(Int_t index,Float_t &eta,Float_t &phi);
    // for a given eta and phi in the EMCAL it returns the tower index.
    Int_t TowerIndexFromEtaPhi(Float_t eta,Float_t phi);
    // for a given eta and phi in the EMCAL it returns the pretower index.
    Int_t PreTowerIndexFromEtaPhi(Float_t eta,Float_t phi);
    // Returns theta and phi (degree) for a given EMCAL cell indecated by relid
    void RelPosInModule(const Int_t *relid,Float_t &theta,Float_t &phi);
    // Returns an array indicating the Tower/preshower, iz, and iphi for a
    // specific EMCAL indes.
    Bool_t AbsToRelNumbering(Int_t AbsId, Int_t *relid);
    /*
    // Returns kTRUE if the two indexs are neighboring towers or preshowers.
    Boot_t AliEMCALGeometry::AreNeighbours(Int_t index1,Int_t index2);
 */

 protected:
    AliEMCALGeometry(const Text_t* name, const Text_t* title="") :
	AliGeometry(name, title) {// ctor only for internal usage (singleton)
	Init();
    };
    void Init(void) ;            // initializes the parameters of EMCAL

 private:
    static AliEMCALGeometry * fgGeom ; // pointer to the unique instance
                                       // of the singleton 
    static Bool_t fgInit;// Tells if geometry has been succesfully set up.
    Float_t fAirGap;     // Distance between envelop and active material
    Float_t fAlFrontThick; // Thickness of the front Al face of the support box
    Float_t fPreShowerSintThick; // Thickness of the sintilator for the
                                 // preshower part of the calorimeter
    Float_t fFullShowerSintThick;// Thickness of the sintilaor for the full
                                 // shower part of the calorimeter
    Float_t fPbRadThickness; // Thickness of Pb radiators cm.
    Float_t fArm1PhiMin; // Minimum angular position of EMCAL in Phi (degrees)
    Float_t fArm1PhiMax; // Maximum angular position of EMCAL in Phi (degrees)
    Float_t fArm1EtaMin; // Minimum pseudorapidity position of EMCAL in Eta
    Float_t fArm1EtaMax; // Maximum pseudorapidity position of EMCAL in Eta

    // It is assumed that Arm1 and Arm2 have the same following parameters
    Float_t fEnvelop[3];      // the GEANT TUB for the detector 
    Float_t fIPDistance; // Radial Distance of the inner surface of the EMCAL
    Float_t fShellThickness; // Total thickness in (x,y) direction
    Float_t fZLength;        // Total length in z direction
    Float_t fGap2Active;     // Gap between the envelop and the active material
    Int_t   fNLayers;        // Number of layers of material in the R direction
    Int_t   fNZ;             // Number of Towers in the Z direction
    Int_t   fNPhi;           //Number of Towers in the Phi Direction
 
    ClassDef(AliEMCALGeometry,3) // EMCAL geometry class 

};

#endif // AliEMCALGEOMETRY_H