1. Getting source. 
2. Installation.
----------------
   -  create out-of-source build directory ( recommended ):
      > mkdir <build-dir>
   -  move to this newly created directory:
      > cd <build-dir>
   -  run cmake ( ccmake or easiest cmake-gui if available on your system)
      to generate makefiles:
      > cmake -D ROOT_CONFIG_EXECUTABLE=<path-to-root-config>/root-config \\
              -D GEANT4_CONFIG_EXECUTABLE=<path-to-geant4-config>/geant4-config \\
              -D LCIO_DIR=<path-to-where-LCIO-is-installed>  \\
              -D CMAKE_INSTALL_PREFIX=<dir-where-you-want-have-LUCAS-installed> \\
               <buld-dir>
optionally you may use ( if you have installed ) graphical cmake interface ccmake or cmake-gui
 
   -  if cmake completed successfully do:
      > make
      > make install
Now you have created Lucas exe file and root dictionary libLucasDict.so, the latter is needed
to access root tree created by Lucas.

3.Running Lucas.
----------------
  When all above done, change to <dir-where-you-want-have-LUCAS-installed> :
      > cd <dir-where-you-want-have-LUCAS-installed>
  Setup run-time environment :
      > source ./bin/setup.sh    ( or setup.csh if you work in csh environment )
 Now you can start using Lucas, eg.
      > Lucas -h              prints comand-line options 

      > Lucas -i              runs in interactive mode with default detector geometry
                              several macros sources examples can found in installed
                              ./examples/geant4-macros

      > Lucas -s <steering-file-name> 
      this make Lucas read and execute directives from steering file 
      ( see lucas.steer in ./examples). On output you will find:
       - <some_name>.root   ROOT file with simulated hits and MCParticles
       - <some_name>.slcio  LCIO file with info as above
       - LucasGear.xml       LumiCal geometry description needed by Marlin processors

In batch mode results of simulation are writen to ROOT  and LCIO files. ROOT file
can processed with root macros examples installed in ./examples/root-macros. The LCIO 
output can be analysed with Marlin LumicalClusterer processor ( see FCalClusterer package
in ilcsoft ). All parameters names and their default values are listed in lucas.steer
example.