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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkShrinkPolyData.h,v $

  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 vtkShrinkPolyData - shrink cells composing PolyData
// .SECTION Description
// vtkShrinkPolyData shrinks cells composing a polygonal dataset (e.g., 
// vertices, lines, polygons, and triangle strips) towards their centroid. 
// The centroid of a cell is computed as the average position of the
// cell points. Shrinking results in disconnecting the cells from
// one another. The output dataset type of this filter is polygonal data.
//
// During execution the filter passes its input cell data to its
// output. Point data attributes are copied to the points created during the
// shrinking process.

// .SECTION Caveats
// It is possible to turn cells inside out or cause self intersection
// in special cases.
// Users should use the vtkTriangleFilter to triangulate meshes that 
// contain triangle strips.

// .SECTION See Also
// vtkShrinkFilter

#ifndef __vtkShrinkPolyData_h
#define __vtkShrinkPolyData_h

#include "vtkPolyDataAlgorithm.h"

class VTK_GRAPHICS_EXPORT vtkShrinkPolyData : public vtkPolyDataAlgorithm 
{
public:
  static vtkShrinkPolyData *New();
  vtkTypeRevisionMacro(vtkShrinkPolyData,vtkPolyDataAlgorithm);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Set the fraction of shrink for each cell.
  vtkSetClampMacro(ShrinkFactor,double,0.0,1.0);

  // Description:
  // Get the fraction of shrink for each cell.
  vtkGetMacro(ShrinkFactor,double);

protected:
  vtkShrinkPolyData(double sf=0.5);
  ~vtkShrinkPolyData() {};

  int RequestData(vtkInformation *, vtkInformationVector **, vtkInformationVector *);
  double ShrinkFactor;
private:
  vtkShrinkPolyData(const vtkShrinkPolyData&);  // Not implemented.
  void operator=(const vtkShrinkPolyData&);  // Not implemented.
};

#endif
