Logo ROOT   6.18/05
Reference Guide
TGenerator.h
Go to the documentation of this file.
1// @(#)root/eg:$Id$
2// Author: Ola Nordmann 21/09/95
3
4/*************************************************************************
5 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
6 * All rights reserved. *
7 * *
8 * For the licensing terms see $ROOTSYS/LICENSE. *
9 * For the list of contributors see $ROOTSYS/README/CREDITS. *
10 *************************************************************************/
11
12
13//////////////////////////////////////////////////////////////////////////
14// //
15// TGenerator //
16// //
17// Is an base class, that defines the interface of ROOT to various //
18// event generators. Every event generator should inherit from //
19// TGenerator or its subclasses. //
20// //
21// Derived class can overload the member function GenerateEvent //
22// to do the actual event generation (e.g., call PYEVNT or similar). //
23// //
24// The derived class should overload the member function //
25// ImportParticles (both types) to read the internal storage of the //
26// generated event into either the internal TObjArray or the passed //
27// TClonesArray of TParticles. //
28// //
29// If the generator code stores event data in the /HEPEVT/ common block //
30// Then the default implementation of ImportParticles should suffice. //
31// The common block /HEPEVT/ is structed like //
32// //
33// /* C */ //
34// typedef struct { //
35// Int_t nevhep; //
36// Int_t nhep; //
37// Int_t isthep[4000]; //
38// Int_t idhep[4000]; //
39// Int_t jmohep[4000][2]; //
40// Int_t jdahep[4000][2]; //
41// Double_t phep[4000][5]; //
42// Double_t vhep[4000][4]; //
43// } HEPEVT_DEF; //
44// //
45// //
46// C Fortran //
47// COMMON/HEPEVT/NEVHEP,NHEP,ISTHEP(4000),IDHEP(4000), //
48// + JMOHEP(2,4000),JDAHEP(2,4000),PHEP(5,4000),VHEP(4,4000) //
49// INTEGER NEVHEP,NHEP,ISTHEP,IDHEP,JMOHEP,JDAHEP //
50// DOUBLE PRECISION PHEP,VHEP //
51// //
52// The generic member functions SetParameter and GetParameter can be //
53// overloaded to set and get parameters of the event generator. //
54// //
55// Note, if the derived class interfaces a (set of) Fortran common //
56// blocks (like TPythia, TVenus does), one better make the derived //
57// class a singleton. That is, something like //
58// //
59// class MyGenerator : public TGenerator //
60// { //
61// public: //
62// static MyGenerator* Instance() //
63// { //
64// if (!fgInstance) fgInstance = new MyGenerator; //
65// return fgInstance; //
66// } //
67// void GenerateEvent() { ... } //
68// void ImportParticles(TClonesArray* a, Option_t opt="") {...} //
69// Int_t ImportParticles(Option_t opt="") { ... } //
70// Int_t SetParameter(const char* name, Double_t val) { ... } //
71// Double_t GetParameter(const char* name) { ... } //
72// virtual ~MyGenerator() { ... } //
73// protected: //
74// MyGenerator() { ... } //
75// MyGenerator(const MyGenerator& o) { ... } //
76// MyGenerator& operator=(const MyGenerator& o) { ... } //
77// static MyGenerator* fgInstance; //
78// ClassDef(MyGenerator,0); //
79// }; //
80// //
81// Having multiple objects accessing the same common blocks is not //
82// safe. //
83// //
84// concrete TGenerator classes can be loaded in scripts and subseqent- //
85// ly used in compiled code: //
86// //
87// // MyRun.h //
88// class MyRun : public TObject //
89// { //
90// public: //
91// static MyRun* Instance() { ... } //
92// void SetGenerator(TGenerator* g) { fGenerator = g; } //
93// void Run(Int_t n, Option_t* option="") //
94// { //
95// TFile* file = TFile::Open("file.root","RECREATE"); //
96// TTree* tree = new TTree("T","T"); //
97// TClonesArray* p = new TClonesArray("TParticles"); //
98// tree->Branch("particles", &p); //
99// for (Int_t event = 0; event < n; event++) { //
100// fGenerator->GenerateEvent(); //
101// fGenerator->ImportParticles(p,option); //
102// tree->Fill(); //
103// } //
104// file->Write(); //
105// file->Close(); //
106// } //
107// ... //
108// protected: //
109// TGenerator* fGenerator; //
110// ClassDef(MyRun,0); //
111// }; //
112// //
113// // Config.C //
114// void Config() //
115// { //
116// MyRun* run = MyRun::Instance(); //
117// run->SetGenerator(MyGenerator::Instance()); //
118// } //
119// //
120// // main.cxx //
121// int //
122// main(int argc, char** argv) //
123// { //
124// TApplication app("", 0, 0); //
125// gSystem->ProcessLine(".x Config.C"); //
126// MyRun::Instance()->Run(10); //
127// return 0; //
128// } //
129// //
130// This is especially useful for example with TVirtualMC or similar. //
131// //
132//////////////////////////////////////////////////////////////////////////
133
134#ifndef ROOT_TGenerator
135#define ROOT_TGenerator
136
137#include "TNamed.h"
138
139class TBrowser;
140class TParticle;
141class TClonesArray;
142class TObjArray;
143
144class TGenerator : public TNamed {
145
146protected:
147 Float_t fPtCut; //!Pt cut. Do not show primaries below
148 Bool_t fShowNeutrons; //!display neutrons if true
149 TObjArray *fParticles; //->static container of the primary particles
150
151 TGenerator(const TGenerator& tg) :
152 TNamed(tg), fPtCut(tg.fPtCut), fShowNeutrons(tg.fShowNeutrons),fParticles(tg.fParticles) { }
153 TGenerator& operator=(const TGenerator& tg) {
154 if(this!=&tg) {
155 TNamed::operator=(tg); fPtCut=tg.fPtCut; fShowNeutrons=tg.fShowNeutrons;
156 fParticles=tg.fParticles;
157 }
158 return *this;
159 }
160
161public:
162
163 TGenerator(): fPtCut(0), fShowNeutrons(kTRUE), fParticles(0) { } //Used by Dictionary
164 TGenerator(const char *name, const char *title="Generator class");
165 virtual ~TGenerator();
166 virtual void Browse(TBrowser *b);
167 virtual Int_t DistancetoPrimitive(Int_t px, Int_t py);
168 virtual void Draw(Option_t *option="");
169 virtual void ExecuteEvent(Int_t event, Int_t px, Int_t py);
170 virtual void GenerateEvent();
171 virtual Double_t GetParameter(const char* /*name*/) const { return 0.; }
172 virtual Int_t ImportParticles(TClonesArray *particles, Option_t *option="");
173 virtual TObjArray *ImportParticles(Option_t *option="");
174 virtual TParticle *GetParticle(Int_t i) const;
175 Int_t GetNumberOfParticles() const;
176 virtual TObjArray *GetListOfParticles() const {return fParticles;}
177 virtual TObjArray *GetPrimaries(Option_t *option="") {return ImportParticles(option);}
178 Float_t GetPtCut() const {return fPtCut;}
179 virtual void Paint(Option_t *option="");
180 virtual void SetParameter(const char* /*name*/,Double_t /*val*/){}
181 virtual void SetPtCut(Float_t ptcut=0); // *MENU*
182 virtual void SetViewRadius(Float_t rbox = 1000); // *MENU*
183 virtual void SetViewRange(Float_t xmin=-10000,Float_t ymin=-10000,Float_t zmin=-10000
184 ,Float_t xmax=10000,Float_t ymax=10000,Float_t zmax=10000); // *MENU*
185 virtual void ShowNeutrons(Bool_t show=1); // *MENU*
186
187 ClassDef(TGenerator,1) //Event generator interface abstract baseclass
188};
189
190#endif
b
#define b(i)
Definition: RSha256.hxx:100
Int_t
int Int_t
Definition: RtypesCore.h:41
Bool_t
bool Bool_t
Definition: RtypesCore.h:59
Double_t
double Double_t
Definition: RtypesCore.h:55
Float_t
float Float_t
Definition: RtypesCore.h:53
kTRUE
const Bool_t kTRUE
Definition: RtypesCore.h:87
Option_t
const char Option_t
Definition: RtypesCore.h:62
ClassDef
#define ClassDef(name, id)
Definition: Rtypes.h:326
name
char name[80]
Definition: TGX11.cxx:109
xmin
float xmin
Definition: THbookFile.cxx:93
ymin
float ymin
Definition: THbookFile.cxx:93
xmax
float xmax
Definition: THbookFile.cxx:93
ymax
float ymax
Definition: THbookFile.cxx:93
TBrowser
Using a TBrowser one can browse all ROOT objects.
Definition: TBrowser.h:37
TClonesArray
An array of clone (identical) objects.
Definition: TClonesArray.h:32
TGenerator
The interface to various event generators.
Definition: TGenerator.h:144
TGenerator::GetParticle
virtual TParticle * GetParticle(Int_t i) const
Returns pointer to primary number i;.
Definition: TGenerator.cxx:515
TGenerator::GetNumberOfParticles
Int_t GetNumberOfParticles() const
Return the number of particles in the stack.
Definition: TGenerator.cxx:506
TGenerator::GetParameter
virtual Double_t GetParameter(const char *) const
Definition: TGenerator.h:171
TGenerator::SetViewRadius
virtual void SetViewRadius(Float_t rbox=1000)
Set lower and upper values of the view range.
Definition: TGenerator.cxx:549
TGenerator::ExecuteEvent
virtual void ExecuteEvent(Int_t event, Int_t px, Int_t py)
Execute action corresponding to one event.
Definition: TGenerator.cxx:495
TGenerator::Paint
virtual void Paint(Option_t *option="")
Paint one event.
Definition: TGenerator.cxx:528
TGenerator::~TGenerator
virtual ~TGenerator()
Event generator default destructor.
Definition: TGenerator.cxx:176
TGenerator::GenerateEvent
virtual void GenerateEvent()
must be implemented in concrete class (see eg TPythia6)
Definition: TGenerator.cxx:189
TGenerator::GetListOfParticles
virtual TObjArray * GetListOfParticles() const
Definition: TGenerator.h:176
TGenerator::TGenerator
TGenerator(const TGenerator &tg)
Definition: TGenerator.h:151
TGenerator::fShowNeutrons
Bool_t fShowNeutrons
Pt cut. Do not show primaries below.
Definition: TGenerator.h:148
TGenerator::ImportParticles
virtual Int_t ImportParticles(TClonesArray *particles, Option_t *option="")
It reads the /HEPEVT/ common block which has been filled by the GenerateEvent method.
Definition: TGenerator.cxx:270
TGenerator::SetPtCut
virtual void SetPtCut(Float_t ptcut=0)
Set Pt threshold below which primaries are not drawn.
Definition: TGenerator.cxx:537
TGenerator::fParticles
TObjArray * fParticles
display neutrons if true
Definition: TGenerator.h:149
TGenerator::fPtCut
Float_t fPtCut
Definition: TGenerator.h:147
TGenerator::DistancetoPrimitive
virtual Int_t DistancetoPrimitive(Int_t px, Int_t py)
Compute distance from point px,py to objects in event.
Definition: TGenerator.cxx:334
TGenerator::GetPrimaries
virtual TObjArray * GetPrimaries(Option_t *option="")
Definition: TGenerator.h:177
TGenerator::Draw
virtual void Draw(Option_t *option="")
Insert one event in the pad list.
Definition: TGenerator.cxx:348
TGenerator::operator=
TGenerator & operator=(const TGenerator &tg)
Definition: TGenerator.h:153
TGenerator::Browse
virtual void Browse(TBrowser *b)
browse generator
Definition: TGenerator.cxx:324
TGenerator::ShowNeutrons
virtual void ShowNeutrons(Bool_t show=1)
Set flag to display or not neutrons.
Definition: TGenerator.cxx:574
TGenerator::SetViewRange
virtual void SetViewRange(Float_t xmin=-10000, Float_t ymin=-10000, Float_t zmin=-10000, Float_t xmax=10000, Float_t ymax=10000, Float_t zmax=10000)
Set lower and upper values of the view range.
Definition: TGenerator.cxx:559
TGenerator::SetParameter
virtual void SetParameter(const char *, Double_t)
Definition: TGenerator.h:180
TGenerator::GetPtCut
Float_t GetPtCut() const
Definition: TGenerator.h:178
TNamed
The TNamed class is the base class for all named ROOT classes.
Definition: TNamed.h:29
TNamed::operator=
TNamed & operator=(const TNamed &rhs)
TNamed assignment operator.
Definition: TNamed.cxx:51
TObjArray
An array of TObjects.
Definition: TObjArray.h:37
TParticle
Description of the dynamic properties of a particle.
Definition: TParticle.h:26