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

 Program:   Visualization Toolkit
 Module:    vtkUniformGridGhostDataGenerator.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.

 =========================================================================*/
// .NAME vtkUniformGridGhostDataGenerator.h--Ghost generator for uniform grids.
//
// .SECTION Description
//  A concrete implementation of vtkDataSetGhostGenerator for generating ghost
//  data on partitioned uniform grids on a single process. For a distributed
//  data-set see vtkPUniformGridGhostDataGenerator.
//
// .SECTION Caveats
//  <ol>
//   <li>
//    The input multi-block dataset must:
//    <ul>
//      <li> Have the whole-extent set </li>
//      <li> Each block must be an instance of vtkUniformGrid </li>
//      <li> Each block must have its corresponding global extent set in the
//           meta-data using the PIECE_EXTENT() key </li>
//      <li> The spacing of each block is the same </li>
//      <li> All blocks must have the same fields loaded </li>
//    </ul>
//   </li>
//   <li>
//    The code currently does not handle the following cases:
//    <ul>
//      <li>Ghost cells along Periodic boundaries</li>
//      <li>Growing ghost layers beyond the extents of the neighboring grid</li>
//    </ul>
//   </li>
//  </ol>
//
// .SECTION See Also
//  vtkDataSetGhostGenerator, vtkPUniformGhostDataGenerator

#ifndef VTKUNIFORMGRIDGHOSTDATAGENERATOR_H_
#define VTKUNIFORMGRIDGHOSTDATAGENERATOR_H_

#include "vtkFiltersGeometryModule.h" // For export macro
#include "vtkDataSetGhostGenerator.h"

// Forward declarations
class vtkMultiBlockDataSet;
class vtkIndent;
class vtkStructuredGridConnectivity;

class VTKFILTERSGEOMETRY_EXPORT vtkUniformGridGhostDataGenerator :
  public vtkDataSetGhostGenerator
{
public:
  static vtkUniformGridGhostDataGenerator* New();
  vtkTypeMacro(vtkUniformGridGhostDataGenerator,vtkDataSetGhostGenerator);
  void PrintSelf(ostream& os, vtkIndent indent );

protected:
  vtkUniformGridGhostDataGenerator();
  virtual ~vtkUniformGridGhostDataGenerator();

  // Description:
  // Computes the global origin
  void ComputeOrigin(vtkMultiBlockDataSet *in);

  // Description:
  // Computes the global spacing vector
  void ComputeGlobalSpacingVector(vtkMultiBlockDataSet *in);

  // Description:
  // Registers the grid associated with this instance of multi-block.
  void RegisterGrids(vtkMultiBlockDataSet *in);

  // Description:
  // Creates the output
  void CreateGhostedDataSet(
      vtkMultiBlockDataSet *in,
      vtkMultiBlockDataSet *out );

  // Description:
  // Generates ghost layers.
  void GenerateGhostLayers(
      vtkMultiBlockDataSet *in, vtkMultiBlockDataSet *out);

  double GlobalSpacing[3];
  double GlobalOrigin[3];
  vtkStructuredGridConnectivity *GridConnectivity;

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

#endif /* VTKUNIFORMGRIDGHOSTDATAGENERATOR_H_ */
