------------------------------------------------
 The Geant4 Virtual Monte Carlo package
 Copyright (C) 2007 - 2017 Ivana Hrivnacova
 All rights reserved.

 For the licensing terms see geant4_vmc/LICENSE.
 Contact: root-vmc@cern.ch
-------------------------------------------------

Tags (history):
===============
  11/12/2020
  v5-3:
    All packages:
    - Migration to Geant4 10.7
      - Added G4Threading.hh includes where G4MULTITHREADED is used
      - Updated process maps
      - Update commands for setting optical parameters in E06/g4config.in
        and take into account new value of the PDG encoding for opticalphoton
        (-22, was 0 in 10.6.px)

    Tested with VMC 1.0.p3, Geant4 10.7 (with embedded CLHEP 2.4.4.0.)
      Root 6.22/06, VGM 4.8, Garfield master at 17a26cca556f50f16

  24/07/2020
  v5-2:
    Geant4 VMC:
    - Added geometry option geomVMC+RootToGeant4:
      For geometries defined with both VMC and ROOT and Geant4 native navigation.
    - Added commands for user control of the parameters for killing looping
      particles:
      /mcPhysics/useLowLooperThresholds
      /mcPhysics/useHighLooperThresholds
      /mcRun/setLooperThresholdWarningEnergy value unit
      /mcRun/setLooperThresholImportantEnergy value unit
      /mcRun/setNumberOfLooperThresholdTrials value
    - Increase RunAction verbosity level to 3
      Level 2 just adds printing of summary of looping thresholds;
      level 3 adds all other debug printings

    Fixes:
    Geant4 VMC:
    - Fixed caching pointers in TG4PrimaryGeneratorAction
    - Fix in applying zero magnetic fields
    Geant4 VMC, Examples:
    - Fixed generation of root dictionary maps
    - Restored the dictionaries relocability, improve security and clean up for packaging
      (Thanks to Christian Tacke, GSI.)
  
    Tested with VMC 1.0.p3, Geant4 10.6.p02 (with embedded CLHEP 2.4.1.3)
      Root 6.22/00, VGM 4.8, Garfield master at 17a26cca556f50f16

  11/03/2020
  v5-1:
    All packages:
    - Migration to Geant4 10.6.p01
      - Removed G4VIS_USE, G4UI_USE pre-processor options
      - Updated CMake for using Geant4 cmake use file and removed UseGeant4.cmake.
      - Updated size_t types in loops, process maps, TG4BiasingOperation

    Tested with VMC 1.0, Geant4 10.6.p01 (with embedded CLHEP 2.4.1.3)
      Root 6.20/00, VGM 4.8, Garfield master at 940d64b1a5be99a64

  24/02/2020
  v5-0:
    All packages:
    - Added support for building against VMC stand-alone
    - Updated CMake to make the installation relocatable:
      - Removed the obsolete find modules for Geant4 and require CMake config for all required packages
      - Avoid hard-coded library paths in the targets:
      - Added the list of selected ROOT libraries which we depend on (ROOT_DEPS)
      - Added target_include_directories
    - Added script and configuration file for clang-format and applied formatting
      to all  .h, .icc, .cxx files in examples, g4root, mtroot, source
      (except files for Doxygen)
    - Removed trailing whitespaces from all .h, .hh, .icc, .cxx, .cc, .C, .sh, -README-, history, CMake files
    - Upgraded license to GPL 3.0

    Geant4 VMC:
    - Implemented Multiple-engine usage: with this update GEANT4_VMC becomes capable
      of running together with other engines sharing the simulation of one event.
    - Implemented special biasing that allows to activate INCLXX hadronic model in selected media.
    - Improved commands for setting special physics models:
      - Added "setOneRegion" command to supports names with spaces
      - Added support for abc* pattern
      For example:
      /mcPhysics/biasing/setRegions ITS*
         # set biasing to all media starting with ITS
      /mcPhysics/biasing/setOneRegion ITS_SPD-BUS CU KAPTON$
         #set biasing to "ITS_SPD-BUS CU KAPTON$" medium
    - Added recent magnetic field steppers and  set the default to G4DormandPrince745 (as in Geant4)
      - Added steppers:
        G4BogackiShampine[23,45], G4DormandPrince[745,RK56,RK78], G4TsitourasRK45
        and FSAL steppers: G4RK547FEq[1,2,3]
     - Code clean-up in TG4MagneticField
     - Fixed deleting objects in TG4Field
    - Take into account new TVirtualMCApplication::EndOfEvent(), called by MC at the end of
      event before SD's end of event
    - Implemented TGeant4::ProcessEvent() and added TGeant4::FinishEvent()
      This allows event-by-event processing in TGeant4. The FinishEvent() function has to be called by the user after all events have been processed.
    - Added a new command
      /mcPrimaryGenerator/skipUnknownParticles true|false:
      it permits to skip unknown particles (not defined in Geant4) instead of aborting the execution with an exception
    - Simplified TG4Verbose class

    Examples:
    - E01: Added test for gMC->Mixture(.. Float_t) to control a recent bug fix in TGeoMCGeometry
    - Added new E03 example variant: E03c to demonstrate/test multiple engine mode
    - Improved E03: Added [b,c] to the names of classes specific to the example variants
    - Modularise examples test suites and added new command line args of test_suite.sh:
      --examples, --debug, --cmp-ref

    Fixes:
    Geant4 VMC:
    - Fixes in applying cuts:
      - Do not let neutron decay if it is stopped with a specialCut and has assigned the neutron
        killer process.
      - Removed special cut processes which never apply a cut (ForEplus, ForOther).
    - Removed creating Root UI at initialisation :
      this should hopefully fix the break when running in batch mode without GUI observed in ALICE tests on MAC OSX
    - Fixed resetting the primary particles ids
      (thanks to B. Volkel (CERN) for reporting this problems)
    - Fixed stopping a track if called from MCApplication::PreTrack()
      (thanks to B. Volkel, CERN, for reporting this problem)
    - Allow compiling with non Apple Clang on macOS

    G4Root
    - OpNovice: Use "UseGeant4" instead of ${Geant4_USE_FILE}
      (thanks to Oliver Freyermuth (Physics Institute of the University of Bonn))

    Examples:
    - Test suites:
      - Add missing "export" of LD_LIBRARY_PATH in test_suite.sh
      - Use correct path to executables for E03 sub-examples
      (thanks to Oliver Freyermuth (Physics Institute of the University of Bonn))
    - E03:
      - Fixed cut values: Applied the low limit 10keV (the minimal value accepted by Geant3)
      - Fixed generation of dictionary map files
    - ExGarfield: Fixed G3 macros
    - Monopole: Fixed failure when built with Geant4 MT

    Tested with VMC 1.0 (*), Geant4 10.5.p01 (with embedded CLHEP  2.4.1.0)
      Root 6.18/04 (*), VGM 4.6, Garfield master at c5efc3e352101b59e

  (*) VMC 1.0 is ahead of the vmc in ROOT 6.18/04,
  it includes fixes scheduled for the next ROOT tags 6.18/06 and 6.20/00.
  For this reason, the new multiple engine mode works correctly only with the
  VMC stand-alone or with vmc in ROOT master or v6-18-patches or v6-20-patches.

  18/12/2018
  v4-0:
    All packages:
    - Migration to Geant4 10.5
    - Stopped support for Root 5.x version.

    Geant4 VMC:
    - Added support for user defined sensitive detectors and new TVirtualMC…::NIELEdep():
      - Implemented new functions in TVirtualMC:
          void SetSensitiveDetector(const TString &volName, TVirtualMCSensitiveDetector *sd);
          TVirtualMCSensitiveDetector *GetSensitiveDetector(const TString &volName) const;
          void SetExclusiveSDScoring(Bool_t exclusiveSDScoring);
          TVirtualMC::NIELEdep() function
      - Added new UI commands:
          /mcDet/setExclusiveSDScoring true|false
          /mcDet/printUserSDs
    - Updated field classes for changes in Geant4 10.5:
      - Added new TG4Field base class for magnetic, electromagnetic and gravity
        fields which strength is defined via TVirtualMagField.
      - Added new commands to select a field type and activate monopole field:
        /mcMagField/fieldType fieldType
            fieldType = Magnetic | ElectroMagnetic | Gravity
        /mcMagField/setIsMonopole true|false
    - Added monopole physics classes extracted from the Geant4 monopole
      example in a new sub-category, physics_monopole
    - Added TG4RunConfiguration::SetParameter(const TString& name, Double_t value)
      for setting special parameters which need to be set before creating TGeant4,
      actually used for monopole properties:
      monopoleMass, monopoleElCharge, monopoleMagCharge
    - Allow to proceed empty events:
      In TG4PrimaryGeneratorAction: issue just a warning (instead of an exception)
      when there are no particles to be tracked.
      (Requested by ALICE)
    - Added a new command to (in)activate special stacking mechanism:
      /mcTracking/waitPrimary true|false
      (The command is available only when the special stacking action is activated
      in TG4RunConfiguration constructor (in g4Config.C))

    MTRoot:
    - Merged classes in a single TMCRootManager class and removed locking of
      Root IO operations except for creating and deleting Root files.

    Examples:
    - Splitting E03 in two options:
       E03a - scoring via sensitive volumes and MCApplication::Stepping (old way)
       E03b - scoring via sensitive detectors derived from new TVirtualMCSensitiveDetector
              interface
    - Added Monopole example (working only with Geant4)

    Fixes:
    Geant4 VMC:
      - Fixed creating regions with special physics via the command:
        /mcPhysics/emModel/setRegions regionName
        It was failing when the medium name was associated with a material
        with a different name.
      - Process the extra boundary step only for alive tracks.
        (Thanks to Benedikt Volkel for pointing at this inconsistency.)
      - Fixes in application of VMC cuts:
        the DCUTE, DCUTM, BCUTE, BCUTM cuts are applied only in the track first step
        what emulates a production cut
        (This fixes the problem reported by ALICE, JIRA ALIROOT-7121)
      - Fix in implementation of TVirtualMC::VolName(Int_t volId)
        (Thank to A. Morsch, CERN for reporting the problem.)
      - Fix in CMake:
        Comparing the ROOT version with LESS instead of LESS_EQUAL, as it is not available
        in CMake minimum version declared
      - Fix for excluding TMCAutoLock in MTRoot installation.
        TMCAutoLock was excluded from the library but TMCAutoLock.h was still present in
        the installed include

    Tested with Geant4 10.05 (with embedded CLHEP  2.4.1.0)
      Root 6.14/06, VGM 4.4, Garfield master at 07c0ec50a0d3086b3 (*)

    (*) with fixes in MR #1 in https://gitlab.cern.ch/garfield/garfieldpp

  22/01/2018
  v3-6:
    All packages:
    - Migration to Geant4 10.4

    Geant4 VMC:
    - Improved VGM messenger: the VGM objects are created only when processing a
      command. (This prevents from creating an empty ROOT geometry named VGM which
      name may then persist in a user real geometry.)

    Tested with Geant4 10.04 (with embedded CLHEP 2.4.0.0)
      Root 6.12/04 and 5.34/36, VGM 4.4, Garfield v1.0


  27/10/2017
  v3-5:
    Geant4 VMC:
    - Implemented new TVirtualMC functions TrackPosition|Momentum(Float_t& ...)
    - Added calls to new TVirtualMCApplication non-const functions for MT
    - Let execute at rest processes when stopping a particle via user tracking cut:
      this makes the behavior as in Geant3
    - Added a new command which allows to activate skipping neutrinos in external decayer
      (this feature is switched off by default since this version):
      /mcPhysics/skipExtDecayerNeutrino true|false
    - Take into account tracking medium parameter 'ifield = 0':
      - Set zero magnetic field to logical volumes assoiciated with tracking medium
        with 'ifield = 0' if global magnetic field is defined.
      - The feature must be activated with a new command:
        /mcDet/setIsZeroMagField true
    - Added new command for setting gamma to muons cross section factor:
      /mcPhysics/setGammaToMuonsCrossSectionFactor  value

    MTRoot
    - Do not include TMCAutoLock in MTRoot installation since Root version 6.08/06;
      the class was moved in Root since this version

    Fixes:
    All packages:
    - Fixes in CMake build:
      - Handle also a case when -std flag is not defined in root-config --cflags
      - Do not override CMAKE_INSTALL_LIBDIR (thanks to Dennis Klein, GSI)
      - Add support for ROOT compiled with C++14 (thanks to Dario Berzano, CERN)
    Geant4 VMC:
    - Fixed implementations  for performance optimization applied in 3.4:
      - Do not cache pointer to stepping action as this made calls to VMC functions
        inavailable in initialization.
      - Added new function TG4RunManager::CacheMCStack() called from
        TG4PrimaryGeneratorAction::GeneratePrimaries so that the stack can
        be defined by the user up to MCApplication::BeginEvent at latest
    - Do not skip neutrinos in TG4ExtDecayer by default;
      (requirement from Thomas Ruf, ShipSoft)
    - Added AnnihiToMuPair, ee2hadr, GammaToMuPair processes in the VMC process maps
      which were missing
    Examples:
    - Exclude ExGarfield from compilation and tests with Root 6
      (as Garfield++ requires Root 5x)

    Tested with Geant4 10.03.p03 (with embedded CLHEP   2.3.4.3.)
      Root 5.34/36, 6.11/02 and 6.10/08(*), VGM 4.4, Garfield v1.0

    (*) + fix in TGeoManager required when running in Geant4 multi-threaded mode
        (git commit 971ef8af82)


  08/03/2017
  v3-4:
    All packages:
    - Migration to Geant4 10.3.p01

    Geant4 VMC:
    - Implemented new commands to define radiator properties:
      and removed hard-coded values from TG4TransitionRadiationPhysics.
    - Changes for performance optimization (according to suggestion by S, Wenzel, CERN):
      - Cache pointers to the thread-local static in data members of client classes
    - Set the default build mode to RelWithDebInfo (thanks to S. Wenzel, CERN)

    Examples:
    - Example Garfield renamed to ExGarfield
    - Example TR: Define radiator via new commands
    - Example E03:
      Changes for performance optimization (according to suggestion by S, Wenzel, CERN):
      - Cache pointers to the thread-local static in data members of client classes

    Fixes:
    Geant4 VMC:
    - Fix in transforming primaries from TParticle to G4PrimaryParticle:
      do not override the user defined mass with the PDG mass
      - thanks to Oliver Freyermuth (Physics Institute of the University of Bonn).
    - Fixed in applying stack popper process
      Do not force the exclusive step when the parent track is suspended;
      this fixes the problem observed in ALICE simulation.
    - Fixed compilation with gcc 4.9.3 and 5.3.0
      - thanks to Oliver Freyermuth (Physics Institute of the University of Bonn).
    - Fixed CMake warning (policy CMP0042)
    - Fixed handling the default zero value for argv in TG4RunManager:
      (JIRA bug report VMC-7)

    Tested with Geant4 10.03.p01 (with embedded CLHEP   2.3.4.3.)
      Root 5.34/36 and Root 6.08/06, VGM 4.4, Garfield v1.0

  15/01/2016
  v3-3:
    All packages:
    - Migration to Geant4 10.2

    Geant4 VMC:
      - Integration of fast simulation based on the Geant4 framework:
        - Added TG4VUserFastSimulation base class for user defined
          fast simulation models
        - Added TG4GflashFastSimulation and its messenger:
          this makes possible to activate Gflash fast simulation via an option in
          the configuration macro
      - Added support for transition radiation physics:
        - Added TG4TransitionRadiation physics builder, according to
          the Geant4 extended example TestEm10
        - Added new command to define a radiator:
          /mcDet/setRadiator ...
      - Implemented command to override the default G4 production cuts table energy range:
        - /mcPhysics/productionCutsTableEnergyRange
          (used in the Garfield example)

    Examples:
      - Added new examples:
        - Gflash - use of Geant4 GFlash fast simulation
        - Garfield - integration of Garfield++ using Geant4 fast simulation framework
        - TR - use of Geant4 transition radiation physics
      - All new examples use features of Geant4; when run with Geant3 the Geant3
        standard configuration & physics is used
      - The examples should be run in sequential mode.

    Fixes:
    Geant4 VMC:
      - Fix in TG4ParticlesManager::CreateDynamicParticle(TParticle*):
        the particle polarization was not propagated from TParticle to Geant4;
        this affected the particles added to tracking by the user via stackPopper
      - Fixed deleting TG4SpecialControlsV2 instance in MT mode
    Examples:
      - In E06: fixed in cloning MCApplication on workers

    Tested with Geant4 10.02 (with embedded CLHEP  2.3.1.1.)
      Root 5.34/34 and Root 6.06/00, VGM 4.3, Garfield v1.0

  17/08/2015
  v3-2:
    Geant4 VMC:
    - Added support for local magnetic fields.
    - Added cached magnetic field and a related UI command :
        /mcMagneticField/setConstDistance value unit
      The cached magnetic field is created automatically when
      the ConstDistance parameter is set to a non zero value.
    - Added a possibility to include a user defined magnetic field equation of motion
      and its integrator
    - Integrated a new special UrbanMsc model adapted for ALICE EMCAL by V. Ivantchenko
      and introduced a new set of commands (which do not allow invalid configurations):
        /mcPhysics/emModel/setEmModel modelName
        /mcPhysics/emModel/setParticles particleName1 particleName2 ...
        /mcPhysics/emModel/setRegions regionName1 regionName2 ...

    Examples:
    - E03: Added a test configuration for including a user defined magnetic field equation
           of motion and its integrator in example E03 and included the test in test suites
    - E06: Added test for adding tracks in VMC stack by user (in E06 example)
    - A01: Implemented option for use of local magnetic field and
           added a test with use of local fields in test suites

    Fixes:
    Geant4 VMC:
    - Fixed TG4StackPopper class handling adding particles on the stack
      from the user application. The user tracks generated at the last step of parent track
      were not popped to the stack.
    - Fixed implementation of TVirtualMC::IsTrackDisappeared():
      return false if fSuspend, true if fStopAndKill.
    - Use G4PAIPhotModel instead of G4PAIPhotonModel (recommended since Geant4 10.00)
    - Fixed the expected names of output-files from rootcint (required by CMake 3.2.x):
      - thanks to Oliver Freyermuth (Physics Institute of the University of Bonn).

    G4Root (A. Gheata):
      Fixed boundary crossing errors (by A. Gheata)
      -  This error was due to the G4 field propagator which was exiting
         some volume inside the mother and expecting a non-zero step, but in fact
         was entering a daughter volume right away.
      This fixes killing tracks by G4PropagatorInField as:
      *** G4Exception : GeomNav1002
              issued by : G4PropagatorInField::ComputeStep()
      Particle is stuck; it will be killed.
          Zero progress for 51 attempted steps.
          Proposed Step is 1.78471e-05 but Step Taken is 1.78471e-05
         in volume TPC_Drift
      *** This is just a warning message. ***

    Known problems:
    - On MAC OSX, a build option for Root VMC library has to be activated
      for running in MT mode
      o At present, this requires a customised ROOT installation with a
        modification of TMCtls.h in root/montecarlo/vmc/include

    Tested with Geant4 10.01.p02 (with embedded CLHEP 2.2.0.4)
      Root 5.34/26 and Root 6.04/02, VGM 4.3

  19/12/2014
  v3-1:
    All packages:
    - Migration to Geant4 10.1 and Root 6.02/02

    Geant4 VMC:
    Improved implementation of range cuts:
    - The range cut calculated per region for electron is now by default applied
      also to positron and proton
    - Implemented commands which allow to inactivate applying range cuts
      per particle:
      /mcRegions/applyForXYZ true|false  where XYZ=Gamma, Electron,Positron,Proton
    - Added a command for setting the range cut for proton:
      /mcPhysics/rangeCutForProton
    - Implemented commands to reduce Geant4 output from Geant4 hadronics physics:
      /mcPhysics/g4NeutronHPVerbose
      /mcPhysics/g4HadronicProcessStoreVerbose

    Known problems:
    - The problems listed in v3-0 (related to MT only)  are remaining.
    - test_suite_exe.sh fails for example A01 (during loading geometry from a file)
      with Root 6.02/02 - the problem requires a fix in Root

    Tested with Geant4 10.01 (with embedded CLHEP 2.2.0.4)
      Root 5.34/23 and Root 6.02/02, VGM 4.2

  17/11/2014
  v3-0:
    All packages:
    - Consolidated migration to Geant4  multi-threading
      o Added an option to select to run an application in sequential mode
        also with Geant4 libraries built in MT mode
      o Made setting defined via Geant4 actions available in PreInit phase
    - Migration to Root 6.02/xx
      (note that this involves building against C++11 standard)
    - Migration to CMake build system (and removed "old" Makefiles)
      o see new installation instructions at:
        http://root.cern.ch/drupal/content/installing-geant4vmc-cmake
    - Made use of G4Root package optional

    Geant4 VMC:
    - Removed obsolete "interfaces" category

    G4Root (A. Gheata):
    - Replaced old g4root test based on Geant4 N06 example with a new one based
      on Geant4 OpNovice example (A. Gheata)
    - Enabled Geant4 visualization of bounding box in TG4RootSolid.

    Examples:
    - Separated macros for loading libraries (load_g3|4.C) from run macros
       (run_g3|4.C) - required for cling (Root6)
    - Improved examples test suites:
       o Possibility to select g3/g4 test via arguments
       o Added summary message and return code
       o Possibility to define build dir via arguments

    Fixes:
    - Fixed optional compilation without Geant4 G3toG4 package
    - Fixed TG4GeometryManager destructor
    - Fix in TG4RegionsManager to restore optional regions printing (was affected
      by changes in Geant4 10.0)
    - Fixed description of /mcPhysics/printAllProcess and /mcPhysics/dumpAllProcess
      commands
    - Fixed g4root test geometry (Andrei Gheata)
    - Fixed TG4RootNavigator: added missing include and forward declarations
    - Fix in G4Root for MT mode (by A. Gheata):
      set G4Root navigator also to G4SteppingManager
    - Fixed returning names via const char* (was failing on Mac)
    - Fixed incorrectly used G4cout (instead of G4endl) in TG4SDConstruction.cxx,
      TG4Medium.cxx

    Known problems:
    - Problem at exit in E02 example in MT mode
    - On MAC OSX, a build option for Root VMC library has to be activated
      for running in MT mode
      o At present, this requires a customised ROOT installation with a
        modification of TMCtls.h in root/montecarlo/vmc/include

    Aknowledgment:
     Thanks to Oliver Freyermuth, Physics Institute of the University of Bonn
     for testing CMake build and examples test suites and his contributions.

    Tested with Geant4 10.00.p03 (with embedded CLHEP 2.1.4.1)
      Root 5.34/23 and Root 6.02/01, VGM 4.2

  14/03/2014
  v3-00-b01:
    Migration to Geant4 10.00 MT (beta release)
    Geant4 VMC:
      Developments:
      - Migration to Geant4 multi-threading
      Fixes:
      - Fixed SetDecayMode(): do not fill empty channels (as this causes
        problems in MT)
      - Added protection for zero return from G4ParticleTable::GetParticle(i)
      - Fixed implementation of special controls
      - Fixed compilation with NO_G3TOG4
    Examples:
      Developments:
      - Migration to Geant4 multi-threading
      - Added examples and examples tests main functions and CMake
        configuration files for bulding programs linked with all libraries

    Tested with Geant4 10.00.p01 (with embedded CLHEP 2.1.4.1)
      Root 5.34/18 (+patch in TCint class), VGM 3.06

  10/12/2013
  v2-15:
    Migration to Geant4 10.00
    Geant4 VMC:
    Developments:
    - Applying step limit in low density materials made optional;
      the default step value changed to 10m
    - Added commands:
      /mcDet/setIsUserMaxStep true|false
      /mcDet/setIsMaxStepInLowDensityMaterials true|false
    - TG4SpecialStackingAction adapted for G4SmartTrackStack
      (in Geant4 since 9.6.x);  secondaries are not ordered even
       when the special stacking is activated
    - Added filtering of Geant4 compiler flags in makefiles
      (needed for Geant4 10.0)

    Fixes:
    - Fixed filling optical photon status in TVirtualMC::StepProcess()
    - Fixed setting of PAI model to selected particles in TG4EmModelPhysics
    - Fixed missing initialization in TG4RegionsManager
      (thanks to O. Freyermuth)
    - Fixed g4libs.C to handle correctly using external CLHEP
      (thanks to I. Das)
    - Fixed TG4TrackingAction to work properly with the default stacking of
      optical photons
    - Fixed compiler warnings issued with Geant4 compiler flags not
      enabled by default (mainly shadowed variables)

    Tested with Geant4 10.00 (with embedded CLHEP 2.1.4.1)
      + patch provided at http://bugzilla-geant4.kek.jp/show_bug.cgi?id=1537,
      Root 5.34/13, VGM 3.06

  14/12/2012
  v2-14:
    Migration to Geant4 9.6
    Geant4 VMC:
    Developments:
    - Implemented commands for activating saving random number status
      and restoring it from a file:
    - Improved TG4VSpecialCuts: reorganized code to avoid unnecessary
      calculations before tests
    - Removed obsolete features:
      classes  TG4LVStructure, TG4LVTree, TG4LVTreeMessenger;
      methood TG4EventAction::DisplayEvent; command /mcEvent/drawTracks
    - Added an option to exclude G3toG4 dependent code which can be activated
      by setting NO_G3TOG4 environment variable
    G4Root:
    - Added TG4RootNavigator::GetGlobalExitNormal(), required with Geant4 9.6.
      (A. Gheata)

    Fixes:
    - Fixed mapping between Rootino and geantino;
      user can now introduce chargedgeantino by setting the title
      "ChargedRootino" to Rootino particle.
    - Fixed bug in TVirtualMC::Gdtom() implementation
    - Fixed units in stacking particles
    - Fix in TVirtualMC::GetSecondary implementation: get track global time
      instead of the local one
    - Fixes to support Geant4 native geometries: handling copyNo, taking into
      account the user limits
    - Fixed units in material optical properties

    Examples:
    - Added new A01 example
    - Improved g4vis.in macros and removed use of gean4_vmc commands
      (now removed)
    - In E02, E03: Default physics list changed to FTFP_BERT to be consistent
      with the examples in Geant4 9.6

    Tested with Geant4 9.6 (with embedded CLHEP 2.1.3.1),
      Root 5.34/03, VGM 3.06


  13/12/2011
  v2-13:
    Migration to Geant4 9.5:
    In Makefiles: use of geant4-config if G4INSTALL is not defined

    Geant4 VMC:
    Developments:
    - Implemented a possibility to select sensitive volumes by the user;
      in this case TVirtualMCApplication::Stepping() function is called only when
      track is located in a sensitive volume.
    - Added the user physics selection in the TGeant4 title, so that
      it can be retrievable in a user application.
    - Migration to changes in G4PhysListFactory
      (now all hadronic lists can be combined with all EM options)
    - Modified building of physics list:
      Added TG4ExtraPhysicsList with the following optional Geant4 builders:
      G4ExtraPhysics   -  moved from TG4EmPhysicsList;
      G4OpticalPhysics -  which has replaced TG4OpticalPhysics;
        this implies the changes of commands for configuring optical processes
      G4RadioactiveDecayBuilder - new
    - Faster implementation of TVirtualMC::GetMediumID()
      (the medium ID is now added in TG4SensitiveDetector object)

    Fixes:
    - Fix in GetSecondary(..) (bug reported by L. Zambelli)
      there was missing conversion of units in the returned value of particle
      momentum.
    - Fixing compilation with G4UI_NONE and G4VIS_NONE

    Examples:
    - new g4libs.C macro with use of geant4-config;
      the macro based on liblist renamed to g4libs_old.C;
      previous g4libs_old.C (explicit loading) removed
    - E06:
      - Added setting parameters for Optical Mie Scattering (according N06)
      - Updated configuration optical processes using G4 commands
      - Removed special setting for G3 (it was causing G4 exception
        and seems not to be needed for G3)

    Tested with Geant4 9.5 (with embedded CLHEP 2.1.1.0),
      Root 5.30/04 and Root 5.32/00 + patch in root/etc from rev.42474,
      VGM 3.05

  14/07/2011
  v2-12:
    Migration to Root v5.30/00 and Geant4 9.5.b01

    Geant4 VMC:
    Developments:
    - Implemented new TVirtualMC functions:
      Bool_t GetMaterial(Int_t imat, ...);
      ... which replaced the current Gfmate(...) functions
    - Mapping physics processes from 9.4.p02
    - Adding light anti-ions (ani_deuteron, anti_triton, anti_alpha, anti_He3)
      so that users do not to define them themselves via
      TVirtualMC::DefineParticle.

    Fixes:
    - Coverity defects
    - Fix in TG4ParticlesManager for handling particles which have
      no equivalent in TDatabasePDG: the particle is now added in TDatabasePDG
      without issuing an exception

    Examples:
    - Adding a test for testing all available G4 physics lists
    - Adding a test for the new function GetMaterial() in E01
    - Removing code calling Geant3 visualization functions from all
      examples code and macros
    - Adding a primary generator with anti_nuclei in E03 and added this test
      in test_suite

    Tested with Geant4 9.4.p02 and 9.5.b01, CLHEP 2.1.0.1,
      Root 5.28/00e and Root 5.30/00, VGM 3.04

  22/12/2010
  v2-11:
    Migration to Geant4 9.4 release.

    Tested with Geant4 9.4, CLHEP 2.1.0.1, Root 5.28/00, VGM 3.04

  02/10/2010
  v2-10:
    Geant4 VMC:
    Improvements:
    - Implemented new TVirtualMC functions:
      virtual void   SetCollectTracks(...);
      virtual Bool_t IsCollectTracks() const;
      virtual Bool_t CurrentBoundaryNormal(...) const;
   - Added new TG4EmModelPhysics which allows user selection of an extra
      EM energy loss and fluctuations models.
   -  Adding a utility class, TG4ParticlesChecker, for comparing particles
      properties defined in Root and Geant4 and its messenger
      TG4ParticlesCheckerMessenger.
    - Implemented commands to allow user to customise the setting of the
      the max allowed step in materials with a density below a limit value
    - Added a possbility to switch off passing the random number seed from
      TRandom in CLHEP::HepRandom; this allows using standard Geant4 commands
      for saving and restoring the random number generator status
    - Mapped processed used in CHIPS and QBBC physics lists
    - Migration to Geant4 9.4.b01:
      - updated TG4UserParticlesPhysics, mapped processes present in new

    Fixes:
    - Fixed the time of flight returned via TVirtualMC::TrackPosition():
      return the global track time (= time since the event in which the track
      belongs is created) instead of local track time (= the local time since
      the current track is created) in order to be consistent with Geant3.

    Tested with Geant4 9.3.p02, CLHEP 2.0.4.5, Root 5.27/06, VGM 3.03
            and Geant4 9.4.b01, CLHEP 2.0.4.6

    Examples:
      Removed macros for running examples with Fluka

    Tested with Geant3 1.11, Geant4 VMC 2.10

  20/05/2010
  v2-9:
    G4Root
      - Moved from Root in Geant4 VMC

    Geant4 VMC:
    Improvements:
      - Added new class TG4FieldParameters which allows customization of Geant4
        magnetic field integrator and accuracy parameters.
        (See E02/g4config.in an example of new commands.)
      - Added new class TG4CrossSectionManager which allows inspecting
        hadronic cross sections.
        (See: http://root.cern.ch/drupal/content/physics-list)
      - The available hadron physics lists names are now taken directly from
        G4PhysListFactory.

    Fixes:
      - In TG4RegionsManager:
        - set the range cuts to result always to an energy cut below the user
          cut value.
        - set ranges also for the world volume
        - increased the maximum order of search ranges (to 1km)
        - fixed CheckCut method (the cut from range must be <= VMC cut)
      - In TG4StepManager:
        - Adding its own G4Navigator object, which is used for LocateGlobalPoint...
          calls in pre-track phase.
          (Fixes the problem reported by A. Robert.)
      - In TG4OpGeometryManager, TG4OpticalPhysics
        - Do not set RINDEX material property if defined with zero values.
          (The zero value is a Geant3 convention to define material as metal
          which was not adopted in Geant4, where 0 values cause unpredictable
          behavior in G4OpBoundary process.)
        - The Raileigh and boundary processes were not added to opticalphoton
          process manager.
      - Fix in applying MCApplication::TrackingRMax,TrackingZMax.

    Examples:
      - Frozen testing examples with Fluka.

    Tested with Geant4 9.3.p01, CLHEP 2.0.4.5, Root 5.26/00b, VGM 3.03;

  21/01/2010
  v2-8:
    Geant4 VMC:
    Improvements:
       - In optical physics:
         Implemented new command for user customization
         of optical physics list;
         Changed/added the default parameters:
           fgkDefaultMaxNumPhotons = 20;
           fgkDefaultMaxBetaChange = 1.0;
           fgkDefaultYieldFactor = 1.0;
       - Passing the random number seed from TRandom in CLHEP::HepRandom
         (on the request from FairRoot)
       - Added an option to print memory usage at the end of event
       - Added an option to print all regions
       - New, faster implementation of VMC functions:
           Int_t VolId(const Text_t* volName) const;
           const char* VolName(Int_t id) const;

    Fixes:
      - Fixes in applying VMC cuts:
        - fixed processes names in TG4G3CutVector
        - fix in applying PPCUTM: the cut is now applied as a limit
          to the total energy of e+e- pair procuced by muon;
          the cut is not applied for e+e- pair from gamma conversion
      - Fix in handling feedback photons: keep the feedback photon
          PDG encoding which is different from opticalphoton
      - Fix in applying max step limit
      - Fix in TG4RunConfiguration constructor:
          to handle correctly special physics options.
          Thanks to M. Al-Turany for reporting this problem.
      - Fixes for running with option G4UI_NONE
          Thanks to V. Di Benedetto for reporting this problem.
      - Fixed handling of particle weights
          Thanks to Vito Di Benedetto for pointing at this.

    Tested with Geant4 9.3, CLHEP 2.0.4.5, Root 5.26/00, VGM 3.02;

    Examples:
       - Added an example of magnetic field class Ex02MagField in E02

    Tested with Geant3 1.11, Geant4 VMC 2.8, Fluka VMC 0.4


  15/07/2009
  v2-7:
    Geant4 VMC:
      - Implemented new TVirtualMC function:
        virtual void SetUserParameters(Bool_t isUserParameters);
        which allows to activate the parameters defined in tracking media
        (DEEMAX, STMIN, STEMAX), which are, be default, ignored.
        In Geant4 case, only STEMAX is taken into account.
      - New implementation of VMC cuts via regions;
        this limits the number of secondaries produced beyond
        tracking cuts and speeds up simulation.
      - New implementation of support for special controls (G3 flags):
        The process TG4SpecialControls is replaced with a manager class
        TG4SpecialControlsV2, which functions are colled from tracking
        and stepping functions.
      - When using special stacking action, neutrinos are not killed
        by default, but optionally. This options can be set via a command:
        /mcTracking/skipNeutrino  [true|false]
       Fixes:
      - Fix in applying special controls (the original processes activation
        was not always restored when particle got out from a given tracking
        medium or stopped).
      - Fix in applying SetMaxStep (the original step limit was not always
        restored when particle got out from a given tracking
        medium or stopped).

     Tested with Geant4 9.2.p01, CLHEP 2.0.4.2, Root 5.24/00, VGM 3.02;

   Examples:
      - Fixes in E02 example: fixing a problem reported by A, Robert,
        when using stack for a large events, links to mother particles
        get lost after a few hundreds of events.

     Tested with Geant3 1.11, Geant4 VMC 2.7, Fluka VMC 0.4

  06/03/2009
  v2-6:
    Geant4 VMC:
       - Adaptation to the new TGeo mag field interface
       - Implemented TVirtualMC::SetUserDecay
       - Including the names of Root assemblies in volume names
         when exporting Root geometry in Geant4 (optinal)
       - Removing G4VisManager inheritance from TG4VisManager;
         G4VisExecutive is now used for instatiating G4 visualzation
         drivers
      Fixes:
       - Fix in mapping primary particles Ids in TG4TrackManager.
       - Increase copyNo from divisions by 1 when running with G4 native
         geometry (to be compatible with TGeo numbering.)
       - Migration to gcc 4.3.2

    Examples:
      - Migration to the new TGeo mag field interface
      - Material definition using directly Root objects,
      - Added test for user decay (in E03)
      - Macro g4libs.C replaced with a new one using Geant4 liblist;
        thanks to Ch.H. Christensen and D. Naumov for this development.

    Tested with Geant4 9.2, CLHEP 2.0.4.2, Root 5.23/02, VGM 3.02

  21/07/2008
  v2-5:
    Geant4 VMC:
      - Implemented user defined regions via TG4VUserRegionConstruction
        base class
      - Implemented a possibility to select particles for
        which the external decayer will have a priority over
        using Geant4 decay table; the new command:
        /mcPhysics/setExtDecayerSelection [particleName1 ..]
      - Fix in applying CUTELE (problem reported by Stefano Sparato)
      - Fixing problem (undefined symbols) when running in batch mode
        (reported by Mohammad Al-Turrany)
      - Implemented TVirtualMC::ForceDecayTime()
      - Improved and completed documentation
      - Plus other minor fixes and corrections

    Examples:
      - Adding macros for running with Fluka
      - In E03: added an example for user defined regions in Geant4
      - Adding setting FPE mask to zero, in order to make sure than FPE for
        FE_OVERFLOW is disabled what is required for Geant4.

    Tested with Geant4 9.1.p02, CLHEP 2.0.3.2, Root 5.20/00, VGM 3.01

  18/12/2007
  v2-4:
    Geant4 VMC:
      - Geant4 VMC default physics list replaced with the
        physics lists provided in Geant4 selected by user
        via an option in TG4RunConfiguration class.
        - The classes used for selecting/building physics list
          are now moved in a new directory physics_list
        - The physics constructor classes were renamed
          from  TG4PhysicsConstructorXYZ to TG4XYZPhysics
        - Some command defined in /mcPhysics were changed
          with these modifications
      - Implemented new TVirtualMC functions for user defined
        particles, including their decay channels:
          DefineParticle()
          SetDecayMode()
      - Revised TMCProcess constants, adding new constants
        needed for Geant4 physics in root/vmc

    Examples:
      - In E03: added an example for adding particles and ions
        thanks to Mohammad Al-Turany

    Tested with Geant4 9.1, CLHEP 2.0.3.2, Root 5.17/08, VGM 3.00

  03/07/2007
  v2-3:
    Geant4 VMC:
      - Implemented non zero energy deposit in case of optical
        boundary process with the status Detection
        required by ALICE - thanks to Andrei Gheata
      - Migration to Geant4 9.0

     Tested with Geant4 9.0, CLHEP 2.0.3.1, Root 5.16/00, VGM 2.09


  30/05/2007:
  v2-2:
    Geant4 VMC:
      - Added a special process which pops particles
        defined by user during tracking from the VMC stack
        and passes them to Geant4.
        The process is not activated by default,
        but it has to be set via TG4PhysicsListOptions object.
      - Added an option for storing secondary particles in VMC
        in stepping; by default the secondaries are stored after
        the particle is tracked.
        The saving secondaries in stepping can be selected via
        command: /mcTracking/saveSecondariesInStep true
      - Implemented calls to a new VMC application function
        TVirtualMCApplication::MisalignGeometry()

     Tested with Geant4 8.3, CLHEP 2.0.3.1, Root 5.15/08, VGM 2.09

  22/03/2007:
  v2-1:
    Geant4 VMC:
      - Adding application state, which is updated with each phase
        of MC; the calls to VMC are now checked with respect to
        the application state and a warning is issued of the call happens
        at wrong time.
      - A few fixes for running with G4Root navigation

     Tested with Geant4 8.2.p01, CLHEP 2.0.3.1, Root 5.15/04, VGM 2.08.04

  18/12/2006
  v2-0:
    Geant4 VMC:
      - Added support for G4Root navigation
      - In TG4RunConfiguration user has to specify explicitely
        the way of geometry definition and selected navigation
        via these options:
        - geomVMCtoGeant4   - geometry defined via VMC, G4 native navigation
        - geomVMCtoRoot     - geometry defined via VMC, Root navigation
        - geomRoot          - geometry defined via Root, Root navigation
        - geomRootToGeant4  - geometry defined via Root, G4 native navigation
        - geomGeant4        - geometry defined via Geant4, G4 native navigation
     - Restructuring code in geometry category:
       - Implementation of the VMC functions for building geometry
         now in TG4MCGeometry : TVirtualMCGeometry;
       - TGeant4 instatiates either TG4MCGeometry or TGeoMCGeometry
         depending on user choice
     - Migration to Geant4 8.2:
         Updated TG4ParticlesManager - PDG codes for nuclei now
         defined in Geant4, these codes are used when storing particles
         in the VMC stack

    Examples:
       - In all example geometry is now by default defined via in Root;
         geonmetry defined via VMC is moved in Ex0NDetectorConstractionOld
         class
       - Getting media Id needded for setting cuts or optical properties
         via new function TVirtualMC::MediumId(const Text_t* mediumName)
       - Updated test_suite to include all ways of geometry
         definition/naviagtion, added new run_suite.sh to test run_*C macros

    Tested with Geant4 8.2, CLHEP 2.0.3.1, Root 5.14/00, VGM 2.08.04


  06/07/2006
  v1-9:
    Geant4 VMC:
      Added support for geometry and primary generator defined via Geant4;
      user can now override also functions
      TG4RunConfiguration::CreateDetectorConstruction();
      TG4RunConfiguration::CreatePrimaryGenerator()

    Tested with Geant4 8.1, CLHEP 2.0.2.3, Root 5.11/06, VGM 2.08

  12/01/2006
  v1-8:
    Geant4 VMC:
      Migration to Geant4 8.0:
      - TG4RunConfiguration now only provides functions for creating
        user mandatory and action classes; ConfigureRunManager() function
        is moved in TG4RunManager;
        in a user derived class it now sufficient to override only the
        TG4RunConfiguration::CreatePhysicsList() method.
      - New way of selecting physics via TG4PhysicsListOptions
      - Migration to CLHEP 2.0.2.2

    Tested with Geant4 8.0, CLHEP 1.9.2.2 and 2.0.2.2, Root 5.08/00, VGM 2.07

  22/07/2005
  v1-7:
    Geant4 VMC:
     - Implemented new VMC functions for definition of surfaces
       and material properties for optical physics
     - Added possibility to define maximum number of optical photons
       per step by user (command /mcPhysics/setCerenkovMaxPhotons)

    Examples:
     - Added E06 example which demonstrates Cherenkov and optical photon
       processes

    Tested with Geant4 7.0 and 7.1, Root 5.02/00, VGM 2.05

  29/03/2005
  v1-6:
    Geant4 VMC:
      - Added possibility to use VGM for geometry conversion and
        export to XML as an alternative to geant4_vmc/convertors;
        use of VGM is optional, handled by the environment variable USE_VGM.
        If USE_VGM is set, the VGM is used for all geometry conversions
        by default, old roottog4 convertor can be selected via command:
        /mcDet/useVGM false
        old g4toxml convertor is disabled.
      - Fixed setting cuts and G3 controls via special cuts and
        special control processes.

    Tested with Geant4 7.0, Root 4.03/02, VGM 2.03


  04/01/2005
  v1-5:
    Geant4 VMC:
      Migration to Geant4 version 7.0;
      correction in passing step limits defined in tracking media
      to Geant4.
      Doxygen documentation.

    Examples:
      Added test_suite.sh to test automatically all examples with
      all MCs; added configuration macros for TGeant3TGeo.

    Tested with Geant4 7.0, Root 4.02/00


  05/10/2004
  v1-4:
    Geant4_vmc:
      Updated for modifications in TVirtualMC;
      corrections in Gmtod(), Gdtom() functions

    Convertors
    g4toxml:
      AGDD convertor now generates full AGDD document,
      the TOP.xml file is not needed anymore.
    roottog4:
      Added support for composite shapes;
      Added support for divisions in reflected mothers;
      Corrections in mapping tracking media Ids to G4 logical volumes

    Platform names have been changed according to root-config --arch;
    this changes also the target lib and tmp directories names.
    Tested with Geant4 6.2, Root 4.01/02


  26/04/2004
  v1-3:
    Convertors:
    g4toxml:
      Design updated to support two XML format: AGDD and GDML (new);
      the command for XML file generation changed to
        /xml/generateAGDD [volName]
        /xml/generateGDML [volName]

    roottog4:
       Bug fixes in sphere (rmax); polycone and polyhedra solids
       (do not modify original parameters of TGeo shapes).

    Tested with Geant4 6.1, Root 3.10/02 and Root 4.00/03.


  18/12/2003:
  v1-2:
    Geant4_vmc:
    Update to Geant4 6.0 (removal of g4std, G4std);
    updated physics contructors according to novice examples in
    Geant4 6.0.

    Convertors - g4toxml:
    Corrected export of reflected volumes.

    Tested with Geant4 6.0, Root 3.10/01.


  10/10/2003:
  v1-1:
    Geant4_vmc:
    Implemented new functions from TVirtualMC
    enabling user to define own particles and ions
    + getter functions:
    DefineParticle(..)
    DefineIon(..)
    ParticleName(..) const
    ParticleMass(..) const
    Double_t  ParticleCharge(..) const
    Double_t  ParticleLifeTime(..) const
    TMCParticleType ParticleMCType(..) const

    Examples:
    Update to changes in VMC:
    removed functions TrackingRmax, TrackingZmax (not needed if default is used);
    removed calls to gMC->DefineParticles() in InitMC
    (this function is going to be removed from TVirtualMC).

    Tested with Geant4 5.2, Root 3.10/01.

  21/07/2003:
  v1-0:
    Convertors:
    Added new directory with geometry convertors:
    - roottog4 - convertor from Root to G4 (still in development);
    - g4toxml - convertor from G4 to XML (AGDD) - separated from
                geant4_vmc

    Geant4_vmc:
    Updated for changes in TVirtualMCStack;
    modifications to support geometry defined via TGeo
    using roottog4 convertor.

    Examples:
    In E01 added new functions for building geometry via TGeo
    as an alternative to old way via VMC;
    update for changes in TVirtualStack.

    Tested with Geant4 5.2, Root 3.05/06.

  03/06/2003:
  v0-5:
    geant4_vmc:
    Enabled a user defined physics list:
    TG4VRunConfiguration can be overriden by a user own
    class instantiating a user own physics list
    (derived from G4VUserPhysicsList).
    Update for Geant4 5.1.

    Examples:
    Corrected deleting of MC application
    (to avoid warning from deleting static G4 objects when exiting Root)

    Tested with Geant4 5.1, Root 3.05/04.

  13/03/2003:
  v0-4:
    geant4_vmc:
    Saving secondary particles to MC stack made optional
    (added /mcTracking/saveSecondaries command);
    a few corrections.

    Examples:
    New example E03;
    Corrected implementation in the examples stack classes
    - fixed meaning of the argument done (renamed toBeDone)
    to be consistent with TGeant3 implementation;

    Tested with Geant4 5.0, Root 3.05/03.

  29/01/2003:
  v0-3:
    Update to changes in TVirtualMC;
    the XML convertor classes made independent from Geant4 VMC.
    Tested with Geant4 5.0, Root 3.05/00.

  18/12/2002:
  v0-2:
    Update for new Geant4 version;
    a few corrections (mainly in makefiles).
    Tested with Geant4 5.0, Root 3.04/01.

  12/10/2002:
  v0-1:
    The first released version;
    tested with Geant4 4.1 + patch01, Root 3.03/09.

  20/09/2002:
  First revision:
    Implementation of TVirtualMC interface (in Root) for Geant4;
    source: AliRoot/TGeant4.
    See previous history in AliRoot/AliGeant4/doc/history.