text: /*=========================================================================
   *
   *  Copyright Insight Software Consortium
   *
   *  Licensed under the Apache License, Version 2.0 (the "License");
   *  you may not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *
   *         http://www.apache.org/licenses/LICENSE-2.0.txt
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   *=========================================================================*/
  #ifndef __itkTernaryMagnitudeImageFilter_h
  #define __itkTernaryMagnitudeImageFilter_h
  
  #include "itkTernaryFunctorImageFilter.h"
  
  namespace itk
  {
  namespace Functor
  {
  /**
   * \class Modulus3
   * \brief
   * \ingroup ITKImageIntensity
   */
  template< class TInput1, class TInput2, class TInput3, class TOutput >
  class Modulus3
  {
  public:
    Modulus3() {}
    ~Modulus3() {}
    bool operator!=(const Modulus3 &) const
    {
      return false;
    }
  
    bool operator==(const Modulus3 & other) const
    {
      return !( *this != other );
    }
  
    inline TOutput operator()(const TInput1 & A,
                              const TInput2 & B,
                              const TInput3 & C) const
    { return (TOutput)vcl_sqrt( (double)( A * A + B * B + C * C ) ); }
  };
  }
  /** \class TernaryMagnitudeImageFilter
   * \brief Pixel-wise addition of three images.
   *
   * This class is templated over the types of the three
   * input images and the type of the output image.
   * Numeric conversions (castings) are done by the C++ defaults.
   *
   * \ingroup IntensityImageFilters
   * \ingroup ITKImageIntensity
   */
  template< class TInputImage1, class TInputImage2,
            class TInputImage3, class TOutputImage >
  class ITK_EXPORT TernaryMagnitudeImageFilter:
    public
    TernaryFunctorImageFilter< TInputImage1, TInputImage2,
                               TInputImage3, TOutputImage,
                               Functor::Modulus3<
                                 typename TInputImage1::PixelType,
                                 typename TInputImage2::PixelType,
                                 typename TInputImage3::PixelType,
                                 typename TOutputImage::PixelType >   >
  {
  public:
    /** Standard class typedefs. */
    typedef TernaryMagnitudeImageFilter Self;
    typedef TernaryFunctorImageFilter<
      TInputImage1, TInputImage2,
      TInputImage3, TOutputImage,
      Functor::Modulus3<
        typename TInputImage1::PixelType,
        typename TInputImage2::PixelType,
        typename TInputImage3::PixelType,
        typename TOutputImage::PixelType >
      >                                   Superclass;
  
    typedef SmartPointer< Self >       Pointer;
    typedef SmartPointer< const Self > ConstPointer;
  
    /** Method for creation through the object factory. */
    itkNewMacro(Self);
  
    /** Runtime information support. */
    itkTypeMacro(TernaryMagnitudeImageFilter,
                 TernaryFunctorImageFilter);
  protected:
    TernaryMagnitudeImageFilter() {}
    virtual ~TernaryMagnitudeImageFilter() {}
  private:
    TernaryMagnitudeImageFilter(const Self &); //purposely not implemented
    void operator=(const Self &);              //purposely not implemented
  };
  } // end namespace itk
  
  #endif
  