#ifndef __fpa__Image__Functors__SimpleNeighborhood__hxx__
#define __fpa__Image__Functors__SimpleNeighborhood__hxx__

// -------------------------------------------------------------------------
template< unsigned int _VDim >
typename fpa::Image::Functors::SimpleNeighborhood< _VDim >::
TOutput fpa::Image::Functors::SimpleNeighborhood< _VDim >::
Evaluate( const TIndex& center ) const
{
  if( this->m_Offsets.size( ) == 0 )
  {
    if( this->m_Order == 1 )
      this->_1stCombination( );
    else
      this->_2ndCombination( );

  } // fi

  TOutput res;
  typename TImage::RegionType reg = this->m_Image->GetRequestedRegion( );
  for( int i = 0; i < this->m_Offsets.size( ); ++i )
  {
    TIndex idx = center + this->m_Offsets[ i ];
    if( reg.IsInside( idx ) && idx != center )
      res.push_back( idx );

  } // rof
  return( res );
}

// -------------------------------------------------------------------------
template< unsigned int _VDim >
fpa::Image::Functors::SimpleNeighborhood< _VDim >::
SimpleNeighborhood( )
  : Superclass( ),
    m_Order( 1 )
{
}

// -------------------------------------------------------------------------
template< unsigned int _VDim >
 fpa::Image::Functors::SimpleNeighborhood< _VDim >::
~SimpleNeighborhood( )
{
}

// -------------------------------------------------------------------------
template< unsigned int _VDim >
void fpa::Image::Functors::SimpleNeighborhood< _VDim >::
_1stCombination( ) const
{
  for( int d = 0; d < TImage::ImageDimension; ++d )
  {
    typename TIndex::OffsetType off;
    off.Fill( 0 );
    for( int i = -1; i <= 1; i += 2 )
    {
      off[ d ] = i;
      this->m_Offsets.push_back( off );

    } // rof

  } // rof
}

// -------------------------------------------------------------------------
template< unsigned int _VDim >
void fpa::Image::Functors::SimpleNeighborhood< _VDim >::
_2ndCombination( ) const
{
  std::vector< std::vector< std::vector< int > > > M;
  M.push_back( std::vector< std::vector< int > >( ) );

  std::vector< int > base;
  base.push_back( -1 );
  base.push_back(  0 );
  base.push_back(  1 );
  int dim = TImage::ImageDimension;

  M.push_back( std::vector< std::vector< int > >( ) );
  for( int j = 0; j < base.size( ); ++j )
    M[ 1 ].push_back( std::vector< int >( 1, base[ j ] ) );

  for( int i = 2; i <= dim; ++i )
  {
    M.push_back( std::vector< std::vector< int > >( ) );
    for( int j = 0; j < base.size( ); ++j )
    {
      for( int k = 0; k < M[ i - 1 ].size( ); ++k )
      {
        M[ i ].push_back( std::vector< int >( 1, base[ j ] ) );
        for( int l = 0; l < M[ i - 1 ][ k ].size( ); ++l )
          M[ i ].back( ).push_back( M[ i - 1 ][ k ][ l ] );

      } // rof

    } // rof

  } // rof

  for( int i = 0; i < M[ dim ].size( ); ++i )
  {
    TOffset off;
    for( int j = 0; j < M[ dim ][ i ].size( ); ++j )
      off[ j ] = M[ dim ][ i ][ j ];
    this->m_Offsets.push_back( off );

  } // rof
}

#endif // __fpa__Image__Functors__SimpleNeighborhood__hxx__

// eof - $RCSfile$