Installing VMC

VMC requires ROOT.

The vmc core package was separated from the ROOT source into a new stand-alone vmc package in the GitHub vmc-project organization. The motivation for this step was a gain in flexibility and faster workflow for new developments of multiple engine mode. The vmc package in ROOT is deprecated since ROOT version 6.18 (its compilation is optional) and it is going to be removed in the next ROOT version, 6.26. The VMC stand-alone is then needed for building Geant3 and Geant4 VMC when using ROOT compiled with the vmc disabled (default).

VMC uses CMake to configure a build system for compiling and installing the headers, libraries and Cmake configuration files. To install VMC:

  1. First get the VMC source from the Download page. We will assume that the VMC package sits in a subdirectory
/mypath/vmc
  1. Create build directory alongside our source directory
$ cd /mypath
$ mkdir vmc_build
$ ls
 vmc vmc_build
  1. To configure the build, change into the build directory and run CMake:
$ cd /mypath/vmc_build
$ cmake -DCMAKE_INSTALL_PREFIX=/mypath/vmc_install /mypath/vmc

  • If ROOT environment was defined using thisroot.{c}sh script, there is no need to provide the path to its installation. Otherwise, they can be provided using -DROOT_DIR cmake option.

  • The VMC core is built by default in RelWithDebInfo build mode (Optimized build with debugging symbols). This default can be changed via the standard CMake option CMAKE_BUILD_TYPE. The other useful values are

    • Release : Optimized build, no debugging symbols
    • Debug : Debugging symbols, no optimization
  1. After the configuration has run, CMake will have generated Unix Makefiles for building VMC. To run the build, simply execute make in the build directory:
$ make -jN

where N is the number of parallel jobs you require (e.g. if your machine has a dual core processor, you could set N to 2).

  • If you need more output to help resolve issues or simply for information, run make as
$ make -jN VERBOSE=1
  1. Once the build has completed, you can install VMC to the directory you specified earlier in CMAKE_INSTALL_PREFIX by running
$ make install