centroid_partitioner.h

Go to the documentation of this file.

// The libMesh Finite Element Library.
// Copyright (C) 2002-2018 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner

// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.

// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


#ifndef LIBMESH_CENTROID_PARTITIONER_H
#define LIBMESH_CENTROID_PARTITIONER_H

// Local includes
#include "libmesh/partitioner.h"
#include "libmesh/point.h"
#include "libmesh/auto_ptr.h" // libmesh_make_unique

// C++ includes
#include <utility> // pair
#include <vector>

namespace libMesh
{

// Forward declarations
class Elem;

class CentroidPartitioner : public Partitioner
{
public:

  enum CentroidSortMethod {X=0,
                           Y,
                           Z,
                           RADIAL,
                           INVALID_METHOD};

  explicit
  CentroidPartitioner (const CentroidSortMethod sm=X) : _sort_method(sm) {}

  CentroidPartitioner (const CentroidPartitioner &) = default;
  CentroidPartitioner (CentroidPartitioner &&) = default;
  CentroidPartitioner & operator= (const CentroidPartitioner &) = default;
  CentroidPartitioner & operator= (CentroidPartitioner &&) = default;
  virtual ~CentroidPartitioner() = default;

  virtual std::unique_ptr<Partitioner> clone () const override
  {
    return libmesh_make_unique<CentroidPartitioner>(*this);
  }

  CentroidSortMethod sort_method () const { return _sort_method; }

  void set_sort_method (const CentroidSortMethod sm) { _sort_method = sm; }

  virtual void partition_range(MeshBase & mesh,
                               MeshBase::element_iterator it,
                               MeshBase::element_iterator end,
                               const unsigned int n) override;

protected:

  virtual void _do_partition (MeshBase & mesh,
                              const unsigned int n) override;

private:

  void compute_centroids (MeshBase::element_iterator it,
                          MeshBase::element_iterator end);

  static bool sort_x (const std::pair<Point, Elem *> & lhs,
                      const std::pair<Point, Elem *> & rhs);

  static bool sort_y (const std::pair<Point, Elem *> & lhs,
                      const std::pair<Point, Elem *> & rhs);

  static bool sort_z (const std::pair<Point, Elem *> & lhs,
                      const std::pair<Point, Elem *> & rhs);

  static bool sort_radial (const std::pair<Point, Elem *> & lhs,
                           const std::pair<Point, Elem *> & rhs);

  CentroidSortMethod _sort_method;

  std::vector<std::pair<Point, Elem *>> _elem_centroids;
};

} // namespace libMesh

#endif // LIBMESH_CENTROID_PARTITIONER_H