#ifndef __FPA__IMAGE__ALGORITHM__HXX__
#define __FPA__IMAGE__ALGORITHM__HXX__

#include <itkConstNeighborhoodIterator.h>

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
Algorithm( )
  : Superclass( ),
    m_NeighborhoodOrder( 1 )
{
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
~Algorithm( )
{
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
void fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
_BeforeGenerateData( )
{
  this->Superclass::_BeforeGenerateData( );
  this->AllocateOutputs( );
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
void fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
_InitMarks( )
{
  TOutputImage* out = this->GetOutput( );
  this->m_Marks = TMarkImage::New( );
  this->m_Marks->CopyInformation( out );
  this->m_Marks->SetRequestedRegion( out->GetRequestedRegion( ) );
  this->m_Marks->SetBufferedRegion( out->GetBufferedRegion( ) );
  this->m_Marks->Allocate( );
  this->m_Marks->FillBuffer( 0 );
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
void fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
_InitResults( )
{
  this->GetOutput( )->FillBuffer( TScalar( 0 ) );
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
void fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
_DeallocateAuxiliary( )
{
  this->m_Marks = NULL;
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
typename fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
TFrontId fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
_GetMark( const TVertex& v )
{
  if( this->m_Marks->GetRequestedRegion( ).IsInside( v ) )
    return( this->m_Marks->GetPixel( v ) );
  else
    return( 0 );
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
void fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
_Visit( const TNode& n )
{
  if( this->m_Marks->GetRequestedRegion( ).IsInside( n.Vertex ) )
  {
    this->m_Marks->SetPixel( n.Vertex, n.FrontId );
    this->GetOutput( )->SetPixel( n.Vertex, n.Result );

  } // fi
}

// -------------------------------------------------------------------------
template< class _TInputImage, class _TOutputImage >
typename fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
TVertices fpa::Image::Algorithm< _TInputImage, _TOutputImage >::
_GetNeighborhood( const TVertex& v ) const
{
  TVertices neighs;
  auto reg = this->GetInput( )->GetRequestedRegion( );
  if( this->m_NeighborhoodOrder == 1 )
  {
    for( unsigned int d = 0; d < _TInputImage::ImageDimension; d++ )
    {
      for( int i = -1; i <= 1; i += 2 )
      {
        TVertex n = v;
        n[ d ] += i;
        if( reg.IsInside( n ) )
          neighs.push_back( n );

      } // rof

    } // rof
  }
  else
  {
    typedef itk::ConstNeighborhoodIterator< _TInputImage > _TNeighIt;
    typename _TInputImage::SizeType nSize;
    nSize.Fill( 1 );

    _TNeighIt nIt( nSize, this->GetInput( ), reg );
    nIt.SetLocation( v );
    for( unsigned int i = 0; i < nIt.Size( ); i++ )
    {
      TVertex n = nIt.GetIndex( i );
      if( n == v )
        continue;
      if( reg.IsInside( n ) )
        neighs.push_back( n );

    } // rof

  } // fi
  return( neighs );
}

#endif // __FPA__IMAGE__ALGORITHM__HXX__

// eof - $RCSfile$