Added new tool: tnl-decompose-mesh

# This module will try to find METIS and define the following:

#  METIS_FOUND - True iff METIS was found

#  METIS_INCLUDE_DIRS - METIS include directories

#  METIS_LIBRARIES - METIS library paths

find_path(METIS_INCLUDE_DIR metis.h

          PATHS /usr/include /usr/local/include

          DOC "METIS include directory")

find_library(METIS_LIBRARY metis

             PATHS /usr/lib /usr/local/lib ${PROJECT_SOURCE_DIR}/metis

             DOC "Path to METIS library")

include(FindPackageHandleStandardArgs)

# handle the QUIETLY and REQUIRED arguments and set METIS_FOUND to TRUE

# if all listed variables are TRUE

find_package_handle_standard_args(METIS  DEFAULT_MSG

                                  METIS_LIBRARY METIS_INCLUDE_DIR)

mark_as_advanced(METIS_INCLUDE_DIR METIS_LIBRARY)

set(METIS_LIBRARIES ${METIS_LIBRARY})

set(METIS_INCLUDE_DIRS ${METIS_INCLUDE_DIR})

inline std::string getTypeName( float ) { return "Float32"; }

inline std::string getTypeName( double ) { return "Float64"; }

/**

 * Ghost points and ghost cells

 *

 * The following bit fields are consistent with the corresponding VTK enums [1], which in turn

 * are consistent with VisIt ghost zones specification [2].

 *

 * - [1] https://github.com/Kitware/VTK/blob/060f626b8df0b8144ec8f10c41f936b712c0330b/Common/DataModel/vtkDataSetAttributes.h#L118-L138

 * - [2] http://www.visitusers.org/index.php?title=Representing_ghost_data

 */

enum class CellGhostTypes

: std::uint8_t

{

   DUPLICATECELL = 1,        // the cell is present on multiple processors

   HIGHCONNECTIVITYCELL = 2, // the cell has more neighbors than in a regular mesh

   LOWCONNECTIVITYCELL = 4,  // the cell has less neighbors than in a regular mesh

   REFINEDCELL = 8,          // other cells are present that refines it.

   EXTERIORCELL = 16,        // the cell is on the exterior of the data set

   HIDDENCELL = 32           // the cell is needed to maintain connectivity, but the data values should be ignored.

};

enum class PointGhostTypes

: std::uint8_t

{

   DUPLICATEPOINT = 1,  // the cell is present on multiple processors

   HIDDENPOINT = 2      // the point is needed to maintain connectivity, but the data values should be ignored.

};

/**

 * A DataArray with this name is used in the parallel VTK files to indicate ghost regions.

 * Each value must be assigned according to the bit fields PointGhostTypes or CellGhostType.

 *

 * For details, see https://blog.kitware.com/ghost-and-blanking-visibility-changes/

 */

inline const char* ghostArrayName()

{

   return "vtkGhostType";

}

} // namespace VTK

} // namespace Meshes

} // namespace TNL

   target_link_libraries(tnl-mesh-converter tinyxml2::tinyxml2)

endif()

find_package( METIS QUIET )

if( METIS_FOUND )

   add_executable(tnl-decompose-mesh tnl-decompose-mesh.cpp)

   target_include_directories(tnl-decompose-mesh PUBLIC ${METIS_INCLUDE_DIRS})

   target_link_libraries(tnl-decompose-mesh ${METIS_LIBRARIES})

   if( ZLIB_FOUND )

      target_compile_definitions(tnl-decompose-mesh PUBLIC "-DHAVE_ZLIB")

      target_include_directories(tnl-decompose-mesh PUBLIC ${ZLIB_INCLUDE_DIRS})

      target_link_libraries(tnl-decompose-mesh ${ZLIB_LIBRARIES})

   endif()

   if( tinyxml2_FOUND )

      target_compile_definitions(tnl-decompose-mesh PUBLIC "-DHAVE_TINYXML2")

      target_link_libraries(tnl-decompose-mesh tinyxml2::tinyxml2)

   endif()

   install( TARGETS tnl-decompose-mesh DESTINATION bin )

endif()

IF( BUILD_CUDA )

   CUDA_ADD_EXECUTABLE( tnl-cuda-arch tnl-cuda-arch.cu )

   INSTALL( TARGETS tnl-cuda-arch