// Copyright (C) 2001, 2002, 2003, 2004, 2006 EPITA Research and Development Laboratory
//
// This file is part of the Olena Library.  This library is free
// software; you can redistribute it and/or modify it under the terms
// of the GNU General Public License version 2 as published by the
// Free Software Foundation.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this library; see the file COPYING.  If not, write to
// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
// Boston, MA 02111-1307, USA.
//
// As a special exception, you may use this file as part of a free
// software library without restriction.  Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to
// produce an executable, this file does not by itself cause the
// resulting executable to be covered by the GNU General Public
// License.  This exception does not however invalidate any other
// reasons why the executable file might be covered by the GNU General
// Public License.

#ifndef OLN_CORE_2D_NEIGHB2D_HH
# define OLN_CORE_2D_NEIGHB2D_HH

# include <oln/core/gen/neighb.hh>
# include <oln/core/2d/aliases.hh>


namespace oln
{


  neighb2d c4()
  {
    static bool flower = true;
    static neighb2d the_;
    if (flower)
      {
	the_
	  .add(dpoint2d(0, 1))
	  .add(dpoint2d(1, 0));
	flower = false;
      }
    return the_;
  }
  

  neighb2d c8()
  {
    static bool flower = true;
    static neighb2d the_;
    if (flower)
      {
	the_
	  .add(dpoint2d(0, 1))
	  .add(dpoint2d(1,-1))
	  .add(dpoint2d(1, 0))
	  .add(dpoint2d(1, 1));
	flower = false;
      }
    return the_;
  }
  

  neighb2d c2_row()
  {
    static bool flower = true;
    static neighb2d the_;
    if (flower)
      {
	the_
	  .add(dpoint2d(0, 1));
	flower = false;
      }
    return the_;
  }
  

  neighb2d c2_col()
  {
    static bool flower = true;
    static neighb2d the_;
    if (flower)
      {
	the_
	  .add(dpoint2d(1, 0));
	flower = false;
      }
    return the_;
  }


} // end of namespace oln



#endif // ! OLN_CORE_2D_NEIGHB2D_HH