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

  Program:   Visualization Toolkit
  Module:    vtkImageLaplacian.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.

=========================================================================*/
/**
 * @class   vtkImageLaplacian
 * @brief   Computes divergence of gradient.
 *
 * vtkImageLaplacian computes the Laplacian (like a second derivative)
 * of a scalar image.  The operation is the same as taking the
 * divergence after a gradient.  Boundaries are handled, so the input
 * is the same as the output.
 * Dimensionality determines how the input regions are interpreted.
 * (images, or volumes). The Dimensionality defaults to two.
 */

#ifndef vtkImageLaplacian_h
#define vtkImageLaplacian_h

#include "vtkImagingGeneralModule.h" // For export macro
#include "vtkThreadedImageAlgorithm.h"

class VTKIMAGINGGENERAL_EXPORT vtkImageLaplacian : public vtkThreadedImageAlgorithm
{
public:
  static vtkImageLaplacian* New();
  vtkTypeMacro(vtkImageLaplacian, vtkThreadedImageAlgorithm);
  void PrintSelf(ostream& os, vtkIndent indent) override;

  //@{
  /**
   * Determines how the input is interpreted (set of 2d slices ...)
   */
  vtkSetClampMacro(Dimensionality, int, 2, 3);
  vtkGetMacro(Dimensionality, int);
  //@}

protected:
  vtkImageLaplacian();
  ~vtkImageLaplacian() override = default;

  int Dimensionality;

  int RequestUpdateExtent(vtkInformation*, vtkInformationVector**, vtkInformationVector*) override;
  void ThreadedRequestData(vtkInformation* request, vtkInformationVector** inputVector,
    vtkInformationVector* outputVector, vtkImageData*** inData, vtkImageData** outData,
    int outExt[6], int id) override;

private:
  vtkImageLaplacian(const vtkImageLaplacian&) = delete;
  void operator=(const vtkImageLaplacian&) = delete;
};

#endif
