The Makefile.lammps file in this directory is used when building
LAMMPS with its USER-VTK package installed.  The file has several
settings needed to compile and link LAMMPS with the VTK library.  You
should choose a Makefile.lammps.* file compatible with your system and
your version of VTK, and copy it to Makefile.lammps before building
LAMMPS itself.  You may need to edit one of the provided files to
match your system.

If you create a new Makefile.lammps file suitable for some version of
VTK on some system, that is not a match to one of the provided
Makefile.lammps.* files, you can send it to the developers, and we can
include it in the distribution for others to use.

To illustrate, these are example settings from the
Makefile.lammps.ubuntu14.04_vtk6 file:

vtk_SYSINC = -I/usr/include/vtk-6.0
vtk_SYSLIB = -lvtkCommonCore-6.0 -lvtkIOCore-6.0 -lvtkIOXML-6.0 -lvtkIOLegacy-6.0 -lvtkCommonDataModel-6.0
vtk_SYSPATH =

vtk_SYSINC refers to the include directory of the installed VTK library

vtk_SYSLIB refers to the libraries needed to link to from an
application (LAMMPS in this case) to "embed" VTK in the
application. VTK consists of multiple shared libraries which are
needed when using the USER-VTK package.

vtk_SYSPATH = refers to the path (e.g. -L/usr/local/lib) where the VTK
library can be found.  You may not need this setting if the path is
already included in your LD_LIBRARY_PATH environment variable.