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

  Program:   Visualization Toolkit
  Module:    vtkCastToConcrete.h
  Language:  C++
  Date:      $Date$
  Version:   $Revision$


Copyright (c) 1993-2000 Ken Martin, Will Schroeder, Bill Lorensen 
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=========================================================================*/
// .NAME vtkCastToConcrete - works around type-checking limitations
// .SECTION Description
// vtkCastToConcrete is a filter that works around type-checking limitations
// in the filter classes. Some filters generate abstract types on output, 
// and cannot be connected to the input of filters requiring a concrete
// input type. For example, vtkElevationFilter generates vtkDataSet for output,
// and cannot be connected to vtkDecimate, because vtkDecimate requires 
// vtkPolyData as input. This is true even though (in this example) the input 
// to vtkElevationFilter is of type vtkPolyData, and you know the output of 
// vtkElevationFilter is the same type as its input.
//
// vtkCastToConcrete performs run-time checking to insure that output type
// is of the right type. An error message will result if you try to cast
// an input type improperly. Otherwise, the filter performs the appropriate
// cast and returns the data.

// .SECTION Caveats
// You must specify the input before you can get the output. Otherwise an
// error results.

// .SECTION See Also
// vtkDataSetToDataSetFilter vtkPointSetToPointSetFilter

#ifndef __vtkCastToConcrete_h
#define __vtkCastToConcrete_h

#include "vtkDataSetToDataSetFilter.h"

class VTK_EXPORT vtkCastToConcrete : public vtkDataSetToDataSetFilter
{

public:
  static vtkCastToConcrete *New();
  vtkTypeMacro(vtkCastToConcrete,vtkDataSetToDataSetFilter);

protected:
  vtkCastToConcrete() {};
  ~vtkCastToConcrete() {};
  vtkCastToConcrete(const vtkCastToConcrete&) {};
  void operator=(const vtkCastToConcrete&) {};

  void Execute(); //insures compatibility; satisfies abstract api in vtkFilter
};

#endif
