User Interface I: Hands-on

We will use the simple example B1 available under the '/examples/basic/' 
directory of the Geant4 code. The goal of the hands-on is to see some of 
the commands, command submission modes that are discussed during the lecture 
in a simple example.    


================================================================================
TaskC0: 
Make a copy of the Geant4 /examples/basic/B1 example and build it:

> cd $G4WORKDIR
> mkdir TaskC
> cd TaskC
> cp -r $G4EXAMPLES/basic/B1 .

Then we will build the application, by creating the build directory inside the 
copied B1 example directory:

> mkdir B1/build
> cd B1/build
> cmake ../ -DGeant4_DIR=$G4COMP
> make

After this we have the executable 'exampleB1' in our (current) 
'$G4WORKDIR/TaskC/B1/build' directory.


================================================================================
TaskC1:
Open the main method ('$G4WORKDIR/TaskC/B1/exampleB1.cc') of the B1 application 
and investigate the 3 different ways of UI command submission: 
 - interactive
 - batch 
 - hard-coded 
 
 Then execute the application in interactive mode:
 
 > $G4WORKDIR/TaskC/B1/build/exampleB1 

 
Deactivate the (Qt) Graphical User Interface and set the C-shell (tcsh) like 
character terminal by:

 1. change (line #55): 
   ui = new G4UIExecutive(argc, argv); 
   to 
   ui = new G4UIExecutive(argc, argv, "tcsh");

 2. and comment the following lines (line # 84, 87, 102 and 112):
   G4VisManager* visManager = new G4VisExecutive;
   visManager->Initialize();
   UImanager->ApplyCommand("/control/execute init_vis.mac");
   delete visManager;
   
Then go to the 'build' directory, rebuild the application and execute again 
in interactive mode:

> cd $G4WORKDIR/TaskC/B1/build/ 
> make
> ./exampleB1

You should see a simple, C-shell like character terminal and you B1 application 
in its Geant4 'PreInit' state waiting for your commands.


================================================================================
TaskC2:
Continue TaskC1 by executing the simulation application using the default 
settings. 

First one needs to initialize the application by:

PreInit>/run/initialize

that brings the application into the Geant4 'Idle' state waiting for further 
commands. If default values will be used for all parameters, one can execute 
the simulation application by:

Idle>/run/beamOn 10  

Investigate the output of the simulation (primary particle type, energy, etc.)


================================================================================
TaskC3:
Continue TaskC2 by executing the simulation now using some of the available 
commands of the Geant4 Particle Gun (that is used go generate primary particles)
in this application: set electrons(e-) as primary particles with 1.0 MeV kinetic
energy:

Idle>/gun/particle e-
Idle>/gun/energy 1.0 MeV
Idle>/run/beamOn 10  

Change the tarcking verbose value to 1 and see what happens:

Idle>/tracking/verbose 1
Idle>/run/beamOn 10  


================================================================================
TaskC4:
Exit the application and execute now the application in batch mode using the 
'run1.mac' macro file.

Way 1.:

Idle>/exit
> ./exampleB1 run1.mac

Way 2.:
> ./exampleB1
PreInit>/control/execute run1.mac

Edit the 'run1.mac' to set primary particle type to electron (e-) and kinetic 
energy to 1.0 MeV. Run the application.