| Geant4 Cross Reference |
>> 1 $Id: README 74479 2013-10-08 14:58:59Z ihrivnac $
1 ---------------------------------------------- 2 -------------------------------------------------------------------
2 3
3 ========================================= 4 =========================================================
4 Geant4 - an Object-Oriented Toolkit for S 5 Geant4 - an Object-Oriented Toolkit for Simulation in HEP
5 ========================================= 6 =========================================================
6 7
7 Example B1 8 Example B1
8 ----------- 9 -----------
9 10
10 This example demonstrates a very simple appli 11 This example demonstrates a very simple application where an energy
11 deposit is accounted in user actions and thei 12 deposit is accounted in user actions and their associated objects
12 and a dose in a selected volume is calculated << 13 and a dose in a selected volume is calculated.
13 <<
14 14
>> 15
15 1- GEOMETRY DEFINITION 16 1- GEOMETRY DEFINITION
16 << 17
17 The geometry is constructed in the B1::Dete << 18 The geometry is constructed in the B1DetectorConstruction class.
18 The setup consists of a an envelope of box 19 The setup consists of a an envelope of box shape containing two
19 volumes: a spherical cone and a trapezoid. 20 volumes: a spherical cone and a trapezoid.
20 21
21 In this example we use some common materia 22 In this example we use some common materials materials for medical
22 applications. The envelope is made of water 23 applications. The envelope is made of water and the two inner volumes
23 are made from tissue and bone materials. << 24 are made from tissue and bone materials.
24 The materials are created with the help of 25 The materials are created with the help of the G4NistManager class,
25 which allows to build a material from the N 26 which allows to build a material from the NIST database using their
26 names. All available materials can be found 27 names. All available materials can be found in the Geant4 User's Guide
27 for Application Developers, Appendix 10: Ge 28 for Application Developers, Appendix 10: Geant4 Materials Database.
28 << 29
29 2- PHYSICS LIST 30 2- PHYSICS LIST
30 << 31
31 The particle's type and the physic processe 32 The particle's type and the physic processes which will be available
32 in this example are set in the QBBC physics << 33 in this example are set in the QBBC physics list. This physics list
33 requires data files for electromagnetic and 34 requires data files for electromagnetic and hadronic processes.
34 See more on installation of the datasets in 35 See more on installation of the datasets in Geant4 Installation Guide,
35 Chapter 3.3: Note On Geant4 Datasets: 36 Chapter 3.3: Note On Geant4 Datasets:
36 http://geant4.web.cern.ch/geant4/UserDocume 37 http://geant4.web.cern.ch/geant4/UserDocumentation/UsersGuides
37 /In 38 /InstallationGuide/html/ch03s03.html
38 The following datasets: G4LEDATA, G4LEVELGA << 39 The following datasets: G4LEDATA, G4LEVELGAMMADATA, G4NEUTRONXSDATA and
39 G4SAIDXSDATA and G4ENSDFSTATEDATA are manda << 40 G4SAIDXSDATA are mandatory for this example.
40 41
41 In addition the build-in interactive comman 42 In addition the build-in interactive command:
42 /process/(in)activate processNa 43 /process/(in)activate processName
43 allows to activate/inactivate the processes 44 allows to activate/inactivate the processes one by one.
44 << 45
45 3- ACTION INITALIZATION 46 3- ACTION INITALIZATION
46 47
47 A newly introduced class, B1::ActionInitial << 48 A newly introduced class, B1ActionInitialization, instantiates and registers
48 to Geant4 kernel all user action classes. 49 to Geant4 kernel all user action classes.
49 50
50 While in sequential mode the action classes 51 While in sequential mode the action classes are instatiated just once,
51 via invoking the method: 52 via invoking the method:
52 B1::ActionInitialization::Build() << 53 B1ActionInitialization::Build()
53 in multi-threading mode the same method is 54 in multi-threading mode the same method is invoked for each thread worker
54 and so all user action classes are defined 55 and so all user action classes are defined thread-local.
55 56
56 A run action class is instantiated both thr << 57 A run action class is instantiated both thread-local
57 and global that's why its instance is creat << 58 and global that's why its instance has is created also in the method
58 B1::ActionInitialization::BuildForMaster << 59 B1ActionInitialization::BuildForMaster()
59 which is invoked only in multi-threading mo 60 which is invoked only in multi-threading mode.
60 << 61
61 4- PRIMARY GENERATOR 62 4- PRIMARY GENERATOR
62 << 63
63 The primary generator is defined in the B1: << 64 The primary generator is defined in the B1PrimaryGeneratorAction class.
64 The default kinematics is a 6 MeV gamma, ra 65 The default kinematics is a 6 MeV gamma, randomly distributed in front
65 of the envelope across 80% of the transvers << 66 of the envelope across 80% of the transverse (X,Y) envelope size.
66 This default setting can be changed via the << 67 This default setting can be changed via the Geant4 built-in commands
67 of the G4ParticleGun class. 68 of the G4ParticleGun class.
68 << 69
69 5- DETECTOR RESPONSE 70 5- DETECTOR RESPONSE
70 71
71 This example demonstrates a simple scoring 72 This example demonstrates a simple scoring implemented directly
72 in the user action classes. Alternative wa << 73 in the user action classes and B1Run object.
73 can be found in the other examples. << 74 Alternative ways of scoring via Geant4 classes can be found in the
74 << 75 other examples.
>> 76
75 The energy deposited is collected step by s 77 The energy deposited is collected step by step for a selected volume
76 in B1::SteppingAction and accumulated event << 78 in B1SteppingAction and accumulated event by event in B1EventAction.
77 << 79
78 At end of event, the value acummulated in B << 80 At end of event, the value acummulated in B1EventAction is added in B1Run
79 and summed over the whole run (see B1::Even << 81 and summed over the whole run (see B1EventAction::EndOfevent()).
80 << 82
81 Total dose deposited is computed at B1::Run << 83 Total dose deposited is computed at B1RunAction::EndOfRunAction(),
82 and printed together with informations abou 84 and printed together with informations about the primary particle.
83 In multi-threading mode the energy accumula << 85
84 workers is merged to the master in B1::RunA << 86 In multi-threading mode the energy accumulated in B1Run objects per
>> 87 workers is merged to the master in B1Run::Merge() and the final
85 result is printed on the screen. 88 result is printed on the screen.
86 89
87 G4Parameter<G4double> type instead of G4dou << 90 An example of creating and computing new units (e.g., dose) is also shown
88 data members in order to facilitate merging << 91 in the class constructor.
89 to the master. Currently the accumulables <<
90 and G4AccumulablesManager::Merge() has to b <<
91 to be further simplified with a closer inte <<
92 the Geant4 kernel next year. <<
93 <<
94 An example of creating and computing new un <<
95 in the class constructor. <<
96 92
97 The following paragraphs are common to all ba 93 The following paragraphs are common to all basic examples
98 94
99 A- VISUALISATION 95 A- VISUALISATION
100 96
101 The visualization manager is set via the G4 97 The visualization manager is set via the G4VisExecutive class
102 in the main() function in exampleB1.cc. << 98 in the main() function in exampleB1.cc.
103 The initialisation of the drawing is done v 99 The initialisation of the drawing is done via a set of /vis/ commands
104 in the macro vis.mac. This macro is automat 100 in the macro vis.mac. This macro is automatically read from
105 the main function when the example is used 101 the main function when the example is used in interactive running mode.
106 102
107 By default, vis.mac opens an OpenGL viewer 103 By default, vis.mac opens an OpenGL viewer (/vis/open OGL).
108 The user can change the initial viewer by c 104 The user can change the initial viewer by commenting out this line
109 and instead uncommenting one of the other / 105 and instead uncommenting one of the other /vis/open statements, such as
110 HepRepFile or DAWNFILE (which produce files 106 HepRepFile or DAWNFILE (which produce files that can be viewed with the
111 HepRApp and DAWN viewers, respectively). N 107 HepRApp and DAWN viewers, respectively). Note that one can always
112 open new viewers at any time from the comma 108 open new viewers at any time from the command line. For example, if
113 you already have a view in, say, an OpenGL 109 you already have a view in, say, an OpenGL window with a name
114 "viewer-0", then 110 "viewer-0", then
115 /vis/open DAWNFILE 111 /vis/open DAWNFILE
116 then to get the same view 112 then to get the same view
117 /vis/viewer/copyView viewer-0 113 /vis/viewer/copyView viewer-0
118 or to get the same view *plus* scene-modifi 114 or to get the same view *plus* scene-modifications
119 /vis/viewer/set/all viewer-0 115 /vis/viewer/set/all viewer-0
120 then to see the result 116 then to see the result
121 /vis/viewer/flush 117 /vis/viewer/flush
122 118
123 The DAWNFILE, HepRepFile drivers are always 119 The DAWNFILE, HepRepFile drivers are always available
124 (since they require no external libraries), 120 (since they require no external libraries), but the OGL driver requires
125 that the Geant4 libraries have been built w 121 that the Geant4 libraries have been built with the OpenGL option.
126 122
127 From Release 9.6 the vis.mac macro in examp 123 From Release 9.6 the vis.mac macro in example B1 has additional commands
128 that demonstrate additional functionality o 124 that demonstrate additional functionality of the vis system, such as
129 displaying text, axes, scales, date, logo a 125 displaying text, axes, scales, date, logo and shows how to change
130 viewpoint and style. Consider copying thes 126 viewpoint and style. Consider copying these to other examples or
131 your application. To see even more command 127 your application. To see even more commands use help or
132 ls or browse the available UI commands in t 128 ls or browse the available UI commands in the Application
133 Developers Guide, Section 7.1. 129 Developers Guide, Section 7.1.
134 130
135 For more information on visualization, incl 131 For more information on visualization, including information on how to
136 install and run DAWN, OpenGL and HepRApp, s 132 install and run DAWN, OpenGL and HepRApp, see the visualization tutorials,
137 for example, 133 for example,
138 http://geant4.slac.stanford.edu/Presentatio 134 http://geant4.slac.stanford.edu/Presentations/vis/G4[VIS]Tutorial/G4[VIS]Tutorial.html
139 (where [VIS] can be replaced by DAWN, OpenG 135 (where [VIS] can be replaced by DAWN, OpenGL and HepRApp)
140 136
141 The tracks are automatically drawn at the e 137 The tracks are automatically drawn at the end of each event, accumulated
142 for all events and erased at the beginning 138 for all events and erased at the beginning of the next run.
143 139
144 B- USER INTERFACES 140 B- USER INTERFACES
145 << 141
146 The user command interface is set via the G 142 The user command interface is set via the G4UIExecutive class
147 in the main() function in exampleB1.cc << 143 in the main() function in exampleB1.cc
148 The selection of the user command interface << 144 The selection of the user command interface is then done automatically
149 according to the Geant4 configuration or it << 145 according to the Geant4 configuration or it can be done explicitly via
150 the third argument of the G4UIExecutive con << 146 the third argument of the G4UIExecutive constructor (see exampleB4a.cc).
151 << 147
152 C- HOW TO RUN 148 C- HOW TO RUN
153 149
154 - Execute exampleB1 in the 'interactive mo 150 - Execute exampleB1 in the 'interactive mode' with visualization:
155 % ./exampleB1 151 % ./exampleB1
156 and type in the commands from run1.mac l << 152 and type in the commands from run1.mac line by line:
157 Idle> /control/verbose 2 153 Idle> /control/verbose 2
158 Idle> /tracking/verbose 1 154 Idle> /tracking/verbose 1
159 Idle> /run/beamOn 10 << 155 Idle> /run/beamOn 10
160 Idle> ... 156 Idle> ...
161 Idle> exit 157 Idle> exit
162 or 158 or
163 Idle> /control/execute run1.mac 159 Idle> /control/execute run1.mac
164 .... 160 ....
165 Idle> exit 161 Idle> exit
166 162
167 - Execute exampleB1 in the 'batch' mode f << 163 - Execute exampleB1 in the 'batch' mode from macro files
168 (without visualization) 164 (without visualization)
169 % ./exampleB1 run2.mac 165 % ./exampleB1 run2.mac
170 % ./exampleB1 exampleB1.in > exampleB1 166 % ./exampleB1 exampleB1.in > exampleB1.out
171 167
172 << 168