##  Geant4  ############################

  * install geant4 (Mac)

    % install xerces-c
    +-------------------------+
    | $ brew install xerces-c |
    +-------------------------+
    % set environment
    +---------------------------------------------------+
    | export G4INSTALL=/usr/local/geant4/geant4.9.6.p02 |
    +---------------------------------------------------+
    % get geant4 code
    +-------------------------------------------------------------------+
    | $ wget http://geant4.cern.ch/support/source/geant4.9.6.p02.tar.gz |
    | $ cd /usr/local                                                   |
    | $ mkdir geant                                                     |
    | $ cd geant                                                        |
    | $ tar zxvf ~/geant4.9.6.p02.tar.gz                                |
    | $ mkdir geant4.9.6.p02-build                                      |
    | $ cd geant4.9.6.p02-build                                         |
    +-------------------------------------------------------------------+
    % make
    +---------------------------------------------------------------------------------------+
    | $ cmake -DCMAKE_INSTALL_PREFIX=/usr/local -DXERCESC_ROOT_DIR=/opt/local \             |
    |   -DGEANT4_USE_OPENGL_X11=ON -DGEANT4_USE_RAYTRACER_X11=ON -DGEANT4_INSTALL_DATA=ON \ |
    |   -DGEANT4_USE_GDML=ON $G4INSTALL                                                     |
    | $ make -j4                                                                            |
    | $ make install                                                                        |
    +---------------------------------------------------------------------------------------+
    NOTE : ln -s /opt/X11 /usr/X11R6 is needed

    % geant.sh
    +---------------------+
    | $ cd /usr/local/bin |
    | $ source geant4.sh  |
    | $ cd -  > /dev/null |
    +---------------------+
    NOTE : DYLD_LIBRARY_PATH should be ""


  * cmake src with ROOT
  +-----------------------------------------------------------------------+
  | $ cmake -DGeant4_DIR=/usr/local/lib/Geant4-9.6.2 \                    |
  |   -DCMAKE_MODULE_PATH=/usr/local/geant/geant4.9.6.p02/cmake/Modules \ |
  |   ../<src_dir>                                                        |
  +-----------------------------------------------------------------------+

  * install VRML (Mac)

    use FreeWRL 
  +-------------------------------------------------------------------------------------------------+
  | $ cd                                                                                            |
  | $ cp /Volumes/FreeWRL\ 1.22.13-Pre1\ install/FreeWRL-1.22.13-pre1.pkg/Contents/Archive.pax.gz . |
  | $ gunzip Archive.pax.gz                                                                         |
  | $ open Archive.pax                                                                              |
  | $ cd unidst                                                                                     |
  | $ cp -pr Applications/FreeWRL /Applications                                                     |
  | $ sudo cp -p usr/local/lib/lib* /usr/local/lib/                                                 |
  | $ sudo cp -p usr/bin/* /usr/local/bin/                                                          |
  +-------------------------------------------------------------------------------------------------+
    % no need ?
    +-----------------------------------------------+
    | $ rm /usr/local/lib/libfree*                  |
    | $ sudo ln -s /opt/X11/lib/libfreetype.6.dylib |
    +-----------------------------------------------+

    export G4VRMLFILE_VIEWER=freewrl  at .zshrc

    /vis/open VRML2FILE
    /vis/viewer/flush


  * cmake error about ROOT

    if geant can not find root path,
    edit /usr/local/geant/geant4.10.00/cmake/Modules/FindROOT.cmake

    +---------------------------------------------+
    | if(NOT ROOT_CONFIG_EXECUTABLE)              |
    |   set(ROOT_FOUND FALSE)                     |
    | else()                                      |
    |   set(ROOT_FOUND TRUE)                      |
    |  ^set(ROOT_CONFIG_EXECUTABLE "root-config")^|
    +---------------------------------------------+


  * suppress G4ParticleGun messages

  +------------------------------------------------------------------------------+
  | ^#include "G4strstreambuf.hh"^                                               |
  |                                                                              |
  | ^G4strstreambuf* oldBuffer = dynamic_cast<G4strstreambuf*>(G4cout.rdbuf(0));^|
  |  ...                                                                         |
  |    particleGun->SetParticleMomentum(G4ThreeVector(px*GeV, py*GeV, pz*GeV));  |
  |  ...                                                                         |
  | ^G4cout.rdbuf(oldBuffer);^                                                   |
  +------------------------------------------------------------------------------+


  * set filter for trajectries in macro

  +-------------------------------------------------------------------------------+
  | /vis/filtering/trajectories/create/particleFilter                             |
  | /vis/filtering/trajectories/particleFilter-0/add <particle>                   |
  |                                                                               |
  | /vis/filtering/trajectories/create/chargeFilter                               |
  | /vis/filtering/trajectories/chargeFilter-0/add <charge>                       |
  |                                                                               |
  | /vis/filtering/trajectories/create/attributeFilter                            |
  | /vis/filtering/trajectories/attributeFilter-0/setAttribute IMag               |
  | /vis/filtering/trajectories/attributeFilter-0/addInterval <min> MeV <max> MeV |
  +-------------------------------------------------------------------------------+
    % particle
      anti_proton, gamma, etc.