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 __itkImageRegionIterator_h
  #define __itkImageRegionIterator_h
  
  #include "itkImageRegionConstIterator.h"
  
  namespace itk
  {
  /** \class ImageRegionIterator
   * \brief A multi-dimensional iterator templated over image type that walks a
   * region of pixels.
   *
   * The itk::ImageRegionIterator is optimized for iteration speed and is the
   * first choice for iterative, pixel-wise operations on an image.
   * ImageRegionIterator is the least specialized of the ITK image iterator
   * classes.  ImageRegionIterator is templated over the image type, and is
   * constrained to walk only within the specified region and along a line
   * parallel to one of the coordinate axes, "wrapping" to the next line as it
   * reaches the boundary of the image.  To walk the entire image, specify the
   * region to be \c image->GetRequestedRegion().
   *
   * Most of the functionality is inherited from the ImageRegionConstIterator.
   * The current class only adds write access to image pixels.
   *
   * \par MORE INFORMATION
   * For a complete description of the ITK Image Iterators and their API, please
   * see the Iterators chapter in the ITK Software Guide.  The ITK Software Guide
   * is available in print and as a free .pdf download from http://www.itk.org.
   *
   * example ImageRegionIterator.cxx
   * \ingroup ImageIterators
   *
   * \sa ImageConstIterator \sa ConditionalConstIterator
   * \sa ConstNeighborhoodIterator \sa ConstShapedNeighborhoodIterator
   * \sa ConstSliceIterator  \sa CorrespondenceDataStructureIterator
   * \sa FloodFilledFunctionConditionalConstIterator
   * \sa FloodFilledImageFunctionConditionalConstIterator
   * \sa FloodFilledImageFunctionConditionalIterator
   * \sa FloodFilledSpatialFunctionConditionalConstIterator
   * \sa FloodFilledSpatialFunctionConditionalIterator
   * \sa ImageConstIterator \sa ImageConstIteratorWithIndex
   * \sa ImageIterator \sa ImageIteratorWithIndex
   * \sa ImageLinearConstIteratorWithIndex  \sa ImageLinearIteratorWithIndex
   * \sa ImageRandomConstIteratorWithIndex  \sa ImageRandomIteratorWithIndex
   * \sa ImageRegionConstIterator \sa ImageRegionConstIteratorWithIndex
   * \sa ImageRegionExclusionConstIteratorWithIndex
   * \sa ImageRegionExclusionIteratorWithIndex
   * \sa ImageRegionIterator  \sa ImageRegionIteratorWithIndex
   * \sa ImageRegionReverseConstIterator  \sa ImageRegionReverseIterator
   * \sa ImageReverseConstIterator  \sa ImageReverseIterator
   * \sa ImageSliceConstIteratorWithIndex  \sa ImageSliceIteratorWithIndex
   * \sa NeighborhoodIterator \sa PathConstIterator  \sa PathIterator
   * \sa ShapedNeighborhoodIterator  \sa SliceIterator
   * \sa ImageConstIteratorWithIndex
   * \ingroup ITKCommon
   *
   * \wiki
   * \wikiexample{Iterators/ImageRegionIterator,Iterate over a region of an image (with write access)}
   * \endwiki
   */
  template< typename TImage >
  class ITK_EXPORT ImageRegionIterator:public ImageRegionConstIterator< TImage >
  {
  public:
    /** Standard class typedefs. */
    typedef ImageRegionIterator                Self;
    typedef ImageRegionConstIterator< TImage > Superclass;
  
    /** Types inherited from the Superclass */
    typedef typename Superclass::IndexType             IndexType;
    typedef typename Superclass::SizeType              SizeType;
    typedef typename Superclass::OffsetType            OffsetType;
    typedef typename Superclass::RegionType            RegionType;
    typedef typename Superclass::ImageType             ImageType;
    typedef typename Superclass::PixelContainer        PixelContainer;
    typedef typename Superclass::PixelContainerPointer PixelContainerPointer;
    typedef typename Superclass::InternalPixelType     InternalPixelType;
    typedef typename Superclass::PixelType             PixelType;
    typedef typename Superclass::AccessorType          AccessorType;
  
    /** Default constructor. Needed since we provide a cast constructor. */
    ImageRegionIterator();
  
    /** Constructor establishes an iterator to walk a particular image and a
     * particular region of that image. */
    ImageRegionIterator(ImageType *ptr, const RegionType & region);
  
    /** Constructor that can be used to cast from an ImageIterator to an
     * ImageRegionIterator. Many routines return an ImageIterator but for a
     * particular task, you may want an ImageRegionIterator.  Rather than
     * provide overloaded APIs that return different types of Iterators, itk
     * returns ImageIterators and uses constructors to cast from an
     * ImageIterator to a ImageRegionIterator. */
    ImageRegionIterator(const ImageIterator< TImage > & it);
  
    /** Set the pixel value */
    void Set(const PixelType & value) const
    {
      this->m_PixelAccessorFunctor.Set(*( const_cast< InternalPixelType * >(
                                            this->m_Buffer + this->m_Offset ) ), value);
    }
  
    /** Return a reference to the pixel
     * This method will provide the fastest access to pixel
     * data, but it will NOT support ImageAdaptors. */
    PixelType & Value(void)
    { return *( const_cast< InternalPixelType * >( this->m_Buffer + this->m_Offset ) ); }
  
    /** Return an iterator for the beginning of the region. "Begin"
     * is defined as the first pixel in the region.
     * \deprecated Use GoToBegin() instead */
    itkLegacyMacro(Self Begin(void) const);
  
    /** Return an iterator for the end of the region. "End" is defined
     * as one pixel past the last pixel of the region.
     * \deprecated Use GoToEnd() instead */
    itkLegacyMacro(Self End(void) const);
  
  protected:
    /** the construction from a const iterator is declared protected
        in order to enforce const correctness. */
    ImageRegionIterator(const ImageRegionConstIterator< TImage > & it);
    Self & operator=(const ImageRegionConstIterator< TImage > & it);
  };
  } // end namespace itk
  
  #ifndef ITK_MANUAL_INSTANTIATION
  #include "itkImageRegionIterator.hxx"
  #endif
  
  #endif
  