TGeoPatternFinder.h

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// @(#)root/geom:$Id$
// Author: Andrei Gheata   30/10/01
 
/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/
 
#ifndef ROOT_TGeoPatternFinder
#define ROOT_TGeoPatternFinder
 
#include "TObject.h"
 
#include <mutex>
#include <vector>
 
#include "TGeoVolume.h"
 
class TGeoMatrix;
 
/////////////////////////////////////////////////////////////////////////////////
//                                                                             //
// TGeoPatternFinder - base finder class for patterns. A pattern is specifying //
// a division type                                                             //
//                                                                             //
/////////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternFinder : public TObject
{
public:
   struct ThreadData_t
   {
      TGeoMatrix      *fMatrix;         //! generic matrix
      Int_t            fCurrent;        //! current division element
      Int_t            fNextIndex;      //! index of next node
 
      ThreadData_t();
      ~ThreadData_t();
   private:
      ThreadData_t(const ThreadData_t&) = delete;
      ThreadData_t& operator=(const ThreadData_t&) = delete;
   };
   ThreadData_t& GetThreadData()   const;
   void          ClearThreadData() const;
   void          CreateThreadData(Int_t nthreads);
 
protected :
   enum EGeoPatternFlags {
      kPatternReflected = BIT(14),
      kPatternSpacedOut = BIT(15)
   };
   Double_t            fStep;           // division step length
   Double_t            fStart;          // starting point on divided axis
   Double_t            fEnd;            // ending point
   Int_t               fNdivisions;     // number of divisions
   Int_t               fDivIndex;       // index of first div. node
   TGeoVolume         *fVolume;         // volume to which applies
 
   mutable std::vector<ThreadData_t*> fThreadData; //! Vector of thread private transient data
   mutable Int_t                      fThreadSize; //! Size of the thread vector
   mutable std::mutex                 fMutex;      //! Mutex for thread data
 
protected:
   TGeoPatternFinder(const TGeoPatternFinder&);
   TGeoPatternFinder& operator=(const TGeoPatternFinder&);
 
public:
   // constructors
   TGeoPatternFinder();
   TGeoPatternFinder(TGeoVolume *vol, Int_t ndiv);
   // destructor
   virtual ~TGeoPatternFinder();
   // methods
   virtual TGeoMatrix* CreateMatrix() const = 0;
   virtual void        cd(Int_t /*idiv*/) {}
   virtual TGeoNode   *CdNext();
   virtual TGeoNode   *FindNode(Double_t * /*point*/, const Double_t * /*dir*/=0) {return 0;}
   virtual Int_t       GetByteCount() const {return 36;}
   Int_t               GetCurrent();//      {return fCurrent;}
   Int_t               GetDivIndex()     {return fDivIndex;}
   virtual Int_t       GetDivAxis()      {return 1;}
   virtual TGeoMatrix *GetMatrix();//       {return fMatrix;}
   Int_t               GetNdiv() const   {return fNdivisions;}
   Int_t               GetNext() const;//   {return fNextIndex;}
   TGeoNode           *GetNodeOffset(Int_t idiv) {return fVolume->GetNode(fDivIndex+idiv);}
   Double_t            GetStart() const  {return fStart;}
   Double_t            GetStep() const   {return fStep;}
   Double_t            GetEnd() const    {return fEnd;}
   TGeoVolume         *GetVolume() const {return fVolume;}
   virtual Bool_t      IsOnBoundary(const Double_t * /*point*/) const {return kFALSE;}
   Bool_t              IsReflected() const {return TObject::TestBit(kPatternReflected);}
   Bool_t              IsSpacedOut() const {return TObject::TestBit(kPatternSpacedOut);}
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE) = 0;
   void                Reflect(Bool_t flag=kTRUE) {TObject::SetBit(kPatternReflected,flag);}
   void                SetDivIndex(Int_t index) {fDivIndex = index;}
   void                SetNext(Int_t index);//     {fNextIndex = index;}
   void                SetRange(Double_t start, Double_t step, Int_t ndivisions);
   void                SetSpacedOut(Bool_t flag) {TObject::SetBit(kPatternSpacedOut,flag);}
   void                SetVolume(TGeoVolume *vol) {fVolume = vol;}
   virtual void        UpdateMatrix(Int_t , TGeoHMatrix &) const {}
 
   ClassDef(TGeoPatternFinder, 4)              // patterns to divide volumes
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternX - a X axis divison pattern                                //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoTranslation;
 
class TGeoPatternX : public TGeoPatternFinder
{
public:
   // constructors
   TGeoPatternX();
   TGeoPatternX(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternX(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternX(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternX(const TGeoPatternX &pf);
   TGeoPatternX& operator=(const TGeoPatternX&);
 
   // destructor
   virtual ~TGeoPatternX();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Double_t    FindNextBoundary(Double_t *point, Double_t *dir, Int_t &indnext);
   virtual Int_t       GetDivAxis()      {return 1;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternX, 1)              // X division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternY - a Y axis divison pattern                                //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternY : public TGeoPatternFinder
{
public:
   // constructors
   TGeoPatternY();
   TGeoPatternY(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternY(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternY(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternY(const TGeoPatternY &pf);
   TGeoPatternY& operator=(const TGeoPatternY&);
   // destructor
   virtual ~TGeoPatternY();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Double_t    FindNextBoundary(Double_t *point, Double_t *dir, Int_t &indnext);
   virtual Int_t       GetDivAxis()      {return 2;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternY, 1)              // Y division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternZ - a Z axis divison pattern                                //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternZ : public TGeoPatternFinder
{
public:
   // constructors
   TGeoPatternZ();
   TGeoPatternZ(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternZ(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternZ(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternZ(const TGeoPatternZ &pf);
   TGeoPatternZ& operator=(const TGeoPatternZ&);
   // destructor
   virtual ~TGeoPatternZ();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Double_t    FindNextBoundary(Double_t *point, Double_t *dir, Int_t &indnext);
   virtual Int_t       GetDivAxis()      {return 3;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternZ, 1)              // Z division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternParaX - a X axis divison pattern for PARA shapes            //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternParaX : public TGeoPatternFinder
{
public:
   // constructors
   TGeoPatternParaX();
   TGeoPatternParaX(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternParaX(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternParaX(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternParaX(const TGeoPatternParaX &pf);
   TGeoPatternParaX& operator=(const TGeoPatternParaX&);
 
   // destructor
   virtual ~TGeoPatternParaX();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 1;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternParaX, 1)              // Para X division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternParaY - a Y axis divison pattern for PARA shapes            //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternParaY : public TGeoPatternFinder
{
private :
// data members
   Double_t         fTxy = 0.;      // tangent of alpha
public:
   // constructors
   TGeoPatternParaY();
   TGeoPatternParaY(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternParaY(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternParaY(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternParaY(const TGeoPatternParaY &pf);
   TGeoPatternParaY& operator=(const TGeoPatternParaY&);
 
   // destructor
   virtual ~TGeoPatternParaY();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 2;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternParaY, 1)              // Para Y division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternParaZ - a Z axis divison pattern for PARA shapes            //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternParaZ : public TGeoPatternFinder
{
private :
// data members
   Double_t            fTxz = 0.;  // tangent of alpha xz
   Double_t            fTyz = 0.;  // tangent of alpha yz
public:
   // constructors
   TGeoPatternParaZ();
   TGeoPatternParaZ(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternParaZ(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternParaZ(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternParaZ(const TGeoPatternParaZ &pf);
   TGeoPatternParaZ& operator=(const TGeoPatternParaZ&);
 
   // destructor
   virtual ~TGeoPatternParaZ();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 3;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternParaZ, 1)              // Para Z division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternTrapZ - a Z axis divison pattern for TRAP or GTRA shapes    //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternTrapZ : public TGeoPatternFinder
{
private :
// data members
   Double_t            fTxz = 0.;  // tangent of alpha xz
   Double_t            fTyz = 0.;  // tangent of alpha yz
public:
   // constructors
   TGeoPatternTrapZ();
   TGeoPatternTrapZ(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternTrapZ(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternTrapZ(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternTrapZ(const TGeoPatternTrapZ &pf);
   TGeoPatternTrapZ& operator=(const TGeoPatternTrapZ&);
 
   // destructor
   virtual ~TGeoPatternTrapZ();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   Double_t            GetTxz() const {return fTxz;}
   Double_t            GetTyz() const {return fTyz;}
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 3;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternTrapZ, 1)              // Trap od Gtra Z division pattern
};
 
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternCylR - a cylindrical R divison pattern                      //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternCylR : public TGeoPatternFinder
{
public:
   // constructors
   TGeoPatternCylR();
   TGeoPatternCylR(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternCylR(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternCylR(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternCylR(const TGeoPatternCylR &pf);
   TGeoPatternCylR& operator=(const TGeoPatternCylR&);
   // destructor
   virtual ~TGeoPatternCylR();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 1;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternCylR, 1)              // Cylindrical R division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternCylPhi - a cylindrical phi divison pattern                  //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternCylPhi : public TGeoPatternFinder
{
private :
// data members
   Double_t           *fSinCos = nullptr;   //![2*fNdivisions] table of sines/cosines
 
protected:
   TGeoPatternCylPhi(const TGeoPatternCylPhi& pfc)
     : TGeoPatternFinder(pfc), fSinCos(pfc.fSinCos) {CreateThreadData(1);}
   TGeoPatternCylPhi& operator=(const TGeoPatternCylPhi& pfc)
     {if(this!=&pfc) {TGeoPatternFinder::operator=(pfc); fSinCos=pfc.fSinCos; CreateThreadData(1);}
     return *this;}
 
public:
   // constructors
   TGeoPatternCylPhi();
   TGeoPatternCylPhi(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternCylPhi(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternCylPhi(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   // destructor
   virtual ~TGeoPatternCylPhi();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 2;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternCylPhi, 1)              // Cylindrical phi division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternSphR - a spherical R divison pattern                        //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternSphR : public TGeoPatternFinder
{
public:
   // constructors
   TGeoPatternSphR();
   TGeoPatternSphR(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternSphR(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternSphR(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternSphR(const TGeoPatternSphR &pf);
   TGeoPatternSphR& operator=(const TGeoPatternSphR&);
   // destructor
   virtual ~TGeoPatternSphR();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 1;}
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternSphR, 1)              // spherical R division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternSphTheta - a spherical theta divison pattern                //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternSphTheta : public TGeoPatternFinder
{
public:
   // constructors
   TGeoPatternSphTheta();
   TGeoPatternSphTheta(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternSphTheta(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternSphTheta(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   TGeoPatternSphTheta(const TGeoPatternSphTheta &pf);
   TGeoPatternSphTheta& operator=(const TGeoPatternSphTheta&);
   // destructor
   virtual ~TGeoPatternSphTheta();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 3;}
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternSphTheta, 1)              // spherical theta division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternSphPhi - a spherical phi divison pattern                    //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternSphPhi : public TGeoPatternFinder
{
private:
   Double_t           *fSinCos = nullptr;         //! Sincos table
 
protected:
   TGeoPatternSphPhi(const TGeoPatternSphPhi& pfc) = delete;
   TGeoPatternSphPhi& operator=(const TGeoPatternSphPhi& pfc) = delete;
   Double_t           *CreateSinCos();
public:
   // constructors
   TGeoPatternSphPhi();
   TGeoPatternSphPhi(TGeoVolume *vol, Int_t ndivisions);
   TGeoPatternSphPhi(TGeoVolume *vol, Int_t ndivisions, Double_t step);
   TGeoPatternSphPhi(TGeoVolume *vol, Int_t ndivisions, Double_t start, Double_t end);
   // destructor
   virtual ~TGeoPatternSphPhi();
   // methods
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual Int_t       GetDivAxis()      {return 2;}
   virtual Bool_t      IsOnBoundary(const Double_t *point) const;
   virtual
   TGeoPatternFinder  *MakeCopy(Bool_t reflect=kFALSE);
   virtual void        SavePrimitive(std::ostream &out, Option_t *option = "");
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternSphPhi, 1)              // Spherical phi division pattern
};
 
////////////////////////////////////////////////////////////////////////////
//                                                                        //
// TGeoPatternHoneycomb - a divison pattern specialized for honeycombs    //
//                                                                        //
////////////////////////////////////////////////////////////////////////////
 
class TGeoPatternHoneycomb : public TGeoPatternFinder
{
private :
// data members
   Int_t               fNrows;                  // number of rows
   Int_t               fAxisOnRows;             // axis along each row
   Int_t              *fNdivisions;             // [fNrows] number of divisions for each row
   Double_t           *fStart;                  // [fNrows] starting points for each row
 
protected:
   TGeoPatternHoneycomb(const TGeoPatternHoneycomb&);
   TGeoPatternHoneycomb& operator=(const TGeoPatternHoneycomb&);
 
public:
   // constructors
   TGeoPatternHoneycomb();
   TGeoPatternHoneycomb(TGeoVolume *vol, Int_t nrows);
   // destructor
   virtual ~TGeoPatternHoneycomb();
   // methods
   TGeoPatternFinder  *MakeCopy(Bool_t) {return 0;}
   virtual TGeoMatrix* CreateMatrix() const;
   virtual void        cd(Int_t idiv);
   virtual TGeoNode   *FindNode(Double_t *point, const Double_t *dir=0);
   virtual void        UpdateMatrix(Int_t idiv, TGeoHMatrix &matrix) const;
 
   ClassDef(TGeoPatternHoneycomb, 1)             // pattern for honeycomb divisions
};
 
#endif