The VMC examples

Introduction

To demonstrate use of VirtualMC, four Geant4 novice examples (N01, N02, N03, N06) has been rewritten as VMC applications: E01, E02, E03, E06.

See more detail description in the README files withing each example subdirectory:

• Example E01
• Example E02
• Example E03
• Example E06

Geometry definition

The VirtualMC defines since beginning the methods for geometry construction in Geant3 style (the functions have the same names and the same parameters sequence as the functions in Geant3). This makes easier transition from Geant3 application to VMC.

Since the integration of the TGeo geometry modeller, user has a possibility to define geometry directly via TGeo, with more user-friendly interfaces.

All VMC examples define by default geometry via TGeo (since Geant4 VMC version 2.0). The equivalent geometry definition via TVirtualMC interface can be activated by setting the option "oldGeometry" to the MC application (via Ex0nMCApplication::SetOldGeometry(kTRUE)).

Macros for running examples

In all examples there are provides macros:

  
  run_g3.C   - for running example with Geant3
  run_g4.C   - for running example with Geant4      
  

Configuration macros:

The selection of the concrete MC, geometry navigation and eventually other options is done in the configuration macros. Here is a list of configuration macros provided with the examples:

  
  g3Config.C      - for G3 with native geometry 
  g3tgeoConfig.C  - for G3 with TGeo geometry (default)

  g4Config.C      - for G4 with native geometry navigation (default)
  g4tgeoConfig.C  - for G4 with TGeo geometry navigation
  xyzOld.C        - the same as above but for geometry defined via VMC

  g4config.in  - macro for G4 configuration using G4 commands
  g4vis.in     - macro for G4 visualization settings
  

To run an example:

  
  With G3 + TGeo:
  root[0] .x run_g3.C

  With G4:
  root[0] .x run_g4.C

  With G4 + TGeo navigation:
  root[0] .x run_g4.C("g4tgeoConfig.C"); 
  

Test macros:

To test all possible configurations, there is provided a test macro for each examples

  
  test_En.C(const TString& configMacro, Bool_t oldGeometry)
  

with parameters:

• configMacro: configuration macro loaded in initialization
• oldGeometry: if true - geometry is defined via VMC, otherwise via TGeo

The tests with all configurations can be run within the test suite:

  
  test_suite.sh
  

which saves all test outputs in the files which names correspond to run configuration:

  test_g3_tgeo_tgeo.out - G3, geometry defined via TGeo, TGeo navigation
  test_g3_vmc_nat.out   - G3, geometry defined via VMC,  G3 native navigation
  test_g3_vmc_tgeo.out  - G3, geometry defined via VMC,  TGeo navigation
  test_g4_tgeo_nat.out  - G4, geometry defined via TGeo, G4 native navigation
  test_g4_tgeo_tgeo.out - G4, geometry defined via TGeo, TGeo navigation
  test_g4_vmc_nat.out   - G4, geometry defined via VMC,  G4 native navigation
  test_g4_vmc_tgeo.out  - G4, geometry defined via VMC,  TGeo navigation
  

The files are saved in log/E0n directory. The reference output files, which are updated with each release, can be found at log_ref directory.

All run_*.C macros can be run via run suite script:

  
  run_suite.sh
  

which saves all output in run_*.out files.