/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkDirectedGraph.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
/*-------------------------------------------------------------------------
  Copyright 2008 Sandia Corporation.
  Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
  the U.S. Government retains certain rights in this software.
-------------------------------------------------------------------------*/
// .NAME vtkDirectedGraph - A directed graph.
//
// .SECTION Description
// vtkDirectedGraph is a collection of vertices along with a collection of
// directed edges (edges that have a source and target). ShallowCopy()
// and DeepCopy() (and CheckedShallowCopy(), CheckedDeepCopy())
// accept instances of vtkTree and vtkMutableDirectedGraph.
//
// vtkDirectedGraph is read-only. To create an undirected graph,
// use an instance of vtkMutableDirectedGraph, then you may set the
// structure to a vtkDirectedGraph using ShallowCopy().
//
// .SECTION See Also
// vtkGraph vtkMutableDirectedGraph

#ifndef __vtkDirectedGraph_h
#define __vtkDirectedGraph_h

#include "vtkGraph.h"

class VTK_FILTERING_EXPORT vtkDirectedGraph : public vtkGraph
{
public:
  static vtkDirectedGraph *New();
  vtkTypeRevisionMacro(vtkDirectedGraph, vtkGraph);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Return what type of dataset this is.
  virtual int GetDataObjectType() {return VTK_DIRECTED_GRAPH;}

  //BTX
  // Description:
  // Retrieve a graph from an information vector.
  static vtkDirectedGraph *GetData(vtkInformation *info);
  static vtkDirectedGraph *GetData(vtkInformationVector *v, int i=0);
  //ETX

protected:
  vtkDirectedGraph();
  ~vtkDirectedGraph();

  // Description:
  // Check the storage, and accept it if it is a valid
  // undirected graph.
  virtual bool IsStructureValid(vtkGraph *g);

private:
  vtkDirectedGraph(const vtkDirectedGraph&);  // Not implemented.
  void operator=(const vtkDirectedGraph&);  // Not implemented.
};

#endif
