Line data    Source code

       1             : // The libMesh Finite Element Library.
       2             : // Copyright (C) 2002-2025 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner
       3             : 
       4             : // This library is free software; you can redistribute it and/or
       5             : // modify it under the terms of the GNU Lesser General Public
       6             : // License as published by the Free Software Foundation; either
       7             : // version 2.1 of the License, or (at your option) any later version.
       8             : 
       9             : // This library is distributed in the hope that it will be useful,
      10             : // but WITHOUT ANY WARRANTY; without even the implied warranty of
      11             : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12             : // Lesser General Public License for more details.
      13             : 
      14             : // You should have received a copy of the GNU Lesser General Public
      15             : // License along with this library; if not, write to the Free Software
      16             : // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
      17             : 
      18             : 
      19             : 
      20             : #ifndef LIBMESH_MESH_SMOOTHER_LAPLACE_H
      21             : #define LIBMESH_MESH_SMOOTHER_LAPLACE_H
      22             : 
      23             : // C++ Includes
      24             : #include <vector>
      25             : 
      26             : // Local Includes
      27             : #include "libmesh/libmesh.h"
      28             : #include "libmesh/mesh_smoother.h"
      29             : 
      30             : namespace libMesh
      31             : {
      32             : 
      33             : /**
      34             :  * This class defines the data structures necessary for Laplace
      35             :  * smoothing.
      36             :  *
      37             :  * \note This is a simple averaging smoother, which does \e not
      38             :  * guarantee that points will be smoothed to valid locations, e.g.
      39             :  * locations inside the boundary!  This aspect could use work.
      40             :  *
      41             :  * \author John W. Peterson
      42             :  * \date 2002-2007
      43             :  */
      44             : class LaplaceMeshSmoother : public MeshSmoother
      45             : {
      46             : public:
      47             :   /**
      48             :    * Constructor.  Sets the constant mesh reference
      49             :    * in the protected data section of the class.
      50             :    */
      51             :   explicit
      52             :   LaplaceMeshSmoother(UnstructuredMesh & mesh);
      53             : 
      54             :   /**
      55             :    * Destructor.
      56             :    */
      57         768 :   virtual ~LaplaceMeshSmoother() = default;
      58             : 
      59             :   /**
      60             :    * Redefinition of the smooth function from the
      61             :    * base class.  All this does is call the smooth
      62             :    * function in this class which takes an int, using
      63             :    * a default value of 1.
      64             :    */
      65           0 :   virtual void smooth() override { this->smooth(1); }
      66             : 
      67             :   /**
      68             :    * The actual smoothing function, gets called whenever
      69             :    * the user specifies an actual number of smoothing
      70             :    * iterations.
      71             :    */
      72             :   void smooth(unsigned int n_iterations);
      73             : 
      74             :   /**
      75             :    * Initialization for the Laplace smoothing routine
      76             :    * is basically identical to building an "L-graph"
      77             :    * which is expensive.  It's provided separately from
      78             :    * the constructor since you may or may not want
      79             :    * to build the L-graph on construction.
      80             :    */
      81             :   void init();
      82             : 
      83             :   /**
      84             :    * Mainly for debugging, this function will print
      85             :    * out the connectivity graph which has been created.
      86             :    */
      87             :   void print_graph(std::ostream & out_stream = libMesh::out) const;
      88             : 
      89             : private:
      90             :   /**
      91             :    * This function allgather's the (local) graph after
      92             :    * it is computed on each processor by the init() function.
      93             :    */
      94             :   void allgather_graph();
      95             : 
      96             :   /**
      97             :    * True if the L-graph has been created, false otherwise.
      98             :    */
      99             :   bool _initialized;
     100             : 
     101             :   /**
     102             :    * Data structure for holding the L-graph
     103             :    */
     104             :   std::vector<std::vector<dof_id_type>> _graph;
     105             : };
     106             : 
     107             : 
     108             : } // namespace libMesh
     109             : 
     110             : #endif // LIBMESH_MESH_SMOOTHER_LAPLACE_H