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

  Program:   Insight Segmentation & Registration Toolkit
  Module:    $RCSfile: itkLaplacianSegmentationLevelSetFunction.h,v $
  Language:  C++
  Date:      $Date: 2004/08/08 12:18:38 $
  Version:   $Revision: 1.8 $

  Copyright (c) Insight Software Consortium. All rights reserved.
  See ITKCopyright.txt or http://www.itk.org/HTML/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 notices for more information.

=========================================================================*/
#ifndef __itkLaplacianSegmentationLevelSetFunction_h_
#define __itkLaplacianSegmentationLevelSetFunction_h_

#include "itkSegmentationLevelSetFunction.h"

namespace itk {


/**
 *
 *
 * Assumes a strictly POSITIVE feature image
 */
template <class TImageType, class TFeatureImageType = TImageType>
class ITK_EXPORT LaplacianSegmentationLevelSetFunction
  : public SegmentationLevelSetFunction<TImageType, TFeatureImageType>
{
public:
  /** Standard class typedefs. */
  typedef LaplacianSegmentationLevelSetFunction Self;
  typedef SegmentationLevelSetFunction<TImageType, TFeatureImageType> Superclass;
  typedef SmartPointer<Self> Pointer;
  typedef SmartPointer<const Self> ConstPointer;
  typedef TFeatureImageType FeatureImageType;

  /** Method for creation through the object factory. */
  itkNewMacro(Self);

  /** Run-time type information (and related methods) */
  itkTypeMacro( LaplacianSegmentationLevelSetFunction, SegmentationLevelSetFunction );

  /** Extract some parameters from the superclass. */
  typedef typename Superclass::ImageType ImageType;
  typedef typename Superclass::ScalarValueType ScalarValueType;
  typedef typename Superclass::FeatureScalarType FeatureScalarType;
  typedef typename Superclass::RadiusType RadiusType;

  /** Extract some parameters from the superclass. */
  itkStaticConstMacro(ImageDimension, unsigned int,
                      Superclass::ImageDimension);


  virtual void CalculateSpeedImage();

  virtual void Initialize(const RadiusType &r)
  {
    Superclass::Initialize(r);
    
    this->SetAdvectionWeight( NumericTraits<ScalarValueType>::Zero);
    this->SetPropagationWeight(-1.0 * NumericTraits<ScalarValueType>::One);
    this->SetCurvatureWeight(NumericTraits<ScalarValueType>::One);
  }
  
  /**
   * The Laplacian level set does not use an advection term. We clamp
   * the value to ZERO here because a superclass may try to set it
   * otherwise. in fact, SegmentationLevelSetImageFilter tries to set
   * it when SetFeatureScaling is called.
   */
  void SetAdvectionWeight(const ScalarValueType value)
    {
      if (value == NumericTraits<ScalarValueType>::Zero)
        {
        Superclass::SetAdvectionWeight(value);
        }
    }

protected:

  LaplacianSegmentationLevelSetFunction()
  {
    this->SetAdvectionWeight(0.0);
    this->SetPropagationWeight(1.0);
    this->SetCurvatureWeight(1.0);
  }
  virtual ~LaplacianSegmentationLevelSetFunction() {}

  LaplacianSegmentationLevelSetFunction(const Self&); //purposely not implemented
  void operator=(const Self&); //purposely not implemented
};
  
} // end namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#include "itkLaplacianSegmentationLevelSetFunction.txx"
#endif

#endif
