gmv_io.h

来自「一个用来实现偏微分方程中网格的计算库」· C头文件 代码 · 共 331 行

// $Id: gmv_io.h 2501 2007-11-20 02:33:29Z benkirk $

// The libMesh Finite Element Library.
// Copyright (C) 2002-2007  Benjamin S. Kirk, John W. Peterson
  
// 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 __gmv_io_h__
#define __gmv_io_h__

// C++ includes
#include <cstring>  // for memcpy
#include <map>

// Local includes
#include "libmesh_common.h"
#include "mesh_output.h"
#include "mesh_input.h"
#include "elem_type.h"

// Forward declarations
class MeshBase;



/**
 * This class implements writing meshes in the GMV format.
 * For a full description of the GMV format and to obtain the
 * GMV software see
 * <a href="http://laws.lanl.gov/XCM/gmv/GMVHome.html">the GMV home page</a>
 *
 * @author Benjamin S. Kirk, 2004
 */

// ------------------------------------------------------------
// GMVIO class definition
class GMVIO : public MeshInput<MeshBase>,
	      public MeshOutput<MeshBase>
{
 public:

  /**
   * Constructor.  Takes a reference to a constant mesh object.
   * This constructor will only allow us to write the mesh.
   */
  GMVIO (const MeshBase&);

  /**
   * Constructor.  Takes a writeable reference to a mesh object.
   * This constructor is required to let us read in a mesh.
   */
  GMVIO (MeshBase&);
  
  /**
   * This method implements writing a mesh to a specified file.
   */
  virtual void write (const std::string& );

   /**
    * This method implements reading a mesh from a specified file.
    */
  virtual void read (const std::string& mesh_file);
  
//   /**
//    * This method implements reading a mesh from a specified file.
//    */
//   virtual void read (const std::string& mesh_file)
//   { this->read_mesh_and_nodal_data(mesh_file, NULL); }

//   /**
//    * Extension of the MeshInput::read() routine which
//    * also takes an optional EquationSystems pointer and
//    * tries to read field variables from the GMV file
//    * into the EquationSystems object.
//    */
//   virtual void read_mesh_and_nodal_data (const std::string& ,
// 					 EquationSystems* es=NULL);
  
  /**
   * This method implements writing a mesh with nodal data to a
   * specified file where the nodal data and variable names are provided.
   */
  virtual void write_nodal_data (const std::string&,
				 const std::vector<Number>&,
				 const std::vector<std::string>&);

  /**
   * Flag indicating whether or not to write a binary file.  While binary
   * files may end up being smaller than equivalent ASCII files, they will
   * almost certainly take longer to write.  The reason for this is that
   * the ostream::write() function which is used to write "binary" data to
   * streams, only takes a pointer to char as its first argument.  This means
   * if you want to write anything other than a buffer of chars, you first
   * have to use a strange memcpy hack to get the data into the desired format.
   * See the templated to_binary_stream() function below.
   */
  bool & binary ();
   
  /**
   * Flag indicating whether or not to write the mesh
   * as discontinuous cell patches
   */
  bool & discontinuous();
  
  /**
   * Flag indicating whether or not to write the partitioning
   * information for the mesh.
   */
  bool & partitioning();
  
  /**
   * Flag indicating whether or not to subdivide second order
   * elements
   */
  bool & subdivide_second_order();
  
  /**
   * Flag indicating whether or not to write p level
   * information for p refined meshes
   */
  bool & p_levels();
  
  /**
   * Writes a GMV file with discontinuous data
   */ 
  void write_discontinuous_gmv (const std::string& name, 
				const EquationSystems& es,
				const bool write_partitioning) const;
  

  /**
   * This method implements writing a mesh with nodal data to a
   * specified file where the nodal data and variable names are optionally
   * provided.  This will write an ASCII file.   This is the new implementation
   * (without subcells).
   */
  void write_ascii_new_impl (const std::string&,
			     const std::vector<Number>* = NULL,
			     const std::vector<std::string>* = NULL);

  /**
   * Takes a vector of cell-centered data to be plotted.
   * You must ensure that for every active element e,
   * v[e->id()] is a valid number.  You can add an arbitrary
   * number of different cell-centered data sets by calling
   * this function multiple times.
   *
   * .) GMV does not like spaces in the cell_centered_data_name
   * .) No matter what order you add cell-centered data, it will be
   *    output alphabetically.
   */
  void add_cell_centered_data (const std::string&       cell_centered_data_name,
			       const std::vector<Real>* cell_centered_data_vals);

  /**
   * If we read in a nodal solution while reading in a mesh, we can attempt
   * to copy that nodal solution into an EquationSystems object.
   */
  void copy_nodal_solution(EquationSystems& es);
  
private:

  /**
   * This method implements writing a mesh with nodal data to a
   * specified file where the nodal data and variable names are optionally
   * provided.  This will write an ASCII file.  This is the old implementation
   * (using subcells) which was the default in libMesh-0.4.3-rc2.
   */
  void write_ascii_old_impl (const std::string&,
			     const std::vector<Number>* = NULL,
			     const std::vector<std::string>* = NULL);

  /**
   * This method implements writing a mesh with nodal data to a
   * specified file where the nodal data and variable names are optionally
   * provided.  
   */
  void write_binary (const std::string&,
		     const std::vector<Number>* = NULL,
		     const std::vector<std::string>* = NULL);
  
  /**
   * Helper function for writing unsigned ints to an ostream in binary format.
   * Implemented via memcpy as suggested in the standard.
   */
  template <typename T>
  void to_binary_stream(std::ostream& out,
			const T i);
  
  /**
   * Flag to write binary data.
   */
  bool _binary;
 
  /**
   * Flag to write the mesh as discontinuous patches.
   */
  bool _discontinuous;
 
  /**
   * Flag to write the mesh partitioning.
   */
  bool _partitioning;
 
  /**
   * Flag to subdivide second order elements
   */
  bool _subdivide_second_order;
 
  /**
   * Flag to write the mesh p refinement levels.
   */
  bool _p_levels;

  /**
   * Storage for arbitrary cell-centered data.  Ex: You can use this
   * to plot the effectivity index for a given cell.  The map is
   * between the string representing the variable name and a pointer
   * to a vector containing the data.
   */
  std::map<std::string, const std::vector<Real>* > _cell_centered_data;

  /**
   * Helper functions for reading nodes/cells from a GMV file
   */
  void _read_nodes();
  unsigned int _next_elem_id;
  void _read_one_cell();
  ElemType _gmv_elem_to_libmesh_elem(const char* elemname);
  void _read_materials();
  void _read_var();
  std::map<std::string, std::vector<Number> > _nodal_data;
};



// ------------------------------------------------------------
// GMVIO inline members
inline
GMVIO::GMVIO (const MeshBase& mesh) :
  MeshOutput<MeshBase>    (mesh),
  _binary                 (false),
  _discontinuous          (false),  
  _partitioning           (true),
  _subdivide_second_order (true),
  _p_levels               (true),
  _next_elem_id           (0)
{
}

inline
GMVIO::GMVIO (MeshBase& mesh) :
  MeshInput<MeshBase> (mesh),
  MeshOutput<MeshBase>(mesh),
  _binary (false),
  _discontinuous          (false),  
  _partitioning           (true),
  _subdivide_second_order (true),
  _p_levels               (true),
  _next_elem_id           (0)
{
}



inline
bool & GMVIO::binary ()
{
  return _binary;
}



inline
bool & GMVIO::discontinuous ()
{
  return _discontinuous;
}



inline
bool & GMVIO::partitioning ()
{
  return _partitioning;
}



inline
bool & GMVIO::subdivide_second_order ()
{
  return _subdivide_second_order;
}



inline
bool & GMVIO::p_levels()
{
  return _p_levels;
}



template <typename T>
void GMVIO::to_binary_stream(std::ostream& out,
			     const T i)
{
  static char buf[sizeof(T)];
  memcpy(buf, &i, sizeof(T));
  out.write(buf, sizeof(T));
}


#endif // #define __gmv_io_h__