Introduction

To demonstrate use of VirtualMC, several Geant4 examples and one Garfield example have been rewritten as VMC applications: E01, E02, E03, E06, A01, ExGarfield, Gflash, Monopole, TR.

The correspondence with the examples in Geant4 (since 10.00.x) is:

E01 - no equivalent
E02 - basic/B2
E03 - basic/B4
E06 - extended/optical/OpNovice
A01 - basic/B5
Gflash - extended/parameterisation/gflash
Monopole - extended/exoticphysics/monopole
TR - extended/electromagnetic/TestEm10

In previous versions of Geant4 (up to 9.6), these examples were provided as novice (N01, N02, N03, N06) and extended (A01, gflash, TestEm10) examples. See more detail description in the README files within each example subdirectory:

Geometry definition

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

Since the integration of the TGeo geometry modeller, users have 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 the example with Geant3
run_g4.C   - for running the example with Geant4

Since Geant4 VMC 3.0 loading of libraries was separated from run_g3[g4].C macros in new macros:

load_g3.C   - loading all libraries needed to run the example with Geant3
load_g4.C   - loading all libraries needed to run the example with Geant4

Configuration macros:

The selection of the concrete MC, geometry navigation and eventually other options is done in the configuration macros. The following configuration macros are 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 load_g3.C
root[1] .x run_g3.C

With G4:
root[0] .x load_g4.C
root[1] .x run_g4.C

With G4 + TGeo navigation:
root[0] .x load_g4.C
root[1] .x run_g4.C("g4tgeoConfig.C");

Test macros:

To test all possible configurations, a test macro (or a set of macros) is provided for each example:

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 via the test suite:

test_suite.sh

which saves all test outputs in the files which names correspond to test 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.