height.hh

// Copyright (C) 2007, 2008, 2009 EPITA Research and Development Laboratory
// (LRDE)
//
// This file is part of Olena.
//
// Olena is free software: you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation, version 2 of the License.
//
// Olena 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 Olena.  If not, see <http://www.gnu.org/licenses/>.
//
// As a special exception, you may use this file as part of a free
// software project 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 MLN_ACCU_SHAPE_HEIGHT_HH
# define MLN_ACCU_SHAPE_HEIGHT_HH

/*
This accumulator uses an mln::util::pix (pixel) to update the
height information of the component.

The class mln/accu/height is not a general-purpose accumulator;
it is used to implement height-based connected filters.
\see mln::morpho::closing::height
\see mln::morpho::opening::height
*/

# include <mln/accu/internal/base.hh>
# include <mln/core/concept/meta_accumulator.hh>

# include <mln/util/pix.hh>
# include <mln/math/min.hh>
# include <mln/math/max.hh>

namespace mln
{

  namespace accu
  {

    namespace shape
    {

      //
      template <typename I>
      struct height
        : public mln::accu::internal::base< unsigned , height<I> >
      {
        typedef util::pix<I> argument;
        typedef typename argument::value value;

        height();

        void init();
        void take(const argument&);
        void take(const height<I>& other);

        void set_value(unsigned h);

        unsigned to_result() const;

        bool is_valid() const;

      protected:
        value min_level__;
        value max_level__;
        unsigned height_;
      };


    } // end of mln::accu::shape


    namespace meta
    {

      namespace shape
      {

        struct height : public Meta_Accumulator< height >
        {
          template <typename I>
          struct with
          {
            typedef accu::shape::height<I> ret;
          };
        };

      } // end of namespace mln::accu::meta::shape

    } // end of namespace mln::accu::meta


# ifndef MLN_INCLUDE_ONLY

    namespace shape
    {

      template <typename I>
      inline
      height<I>::height()
      {
        init();
      }

      template <typename I>
      inline
      void
      height<I>::init()
      {
        min_level__ = mln_max(value);
        max_level__ = mln_min(value);
        height_ = 0;
      }

      template <typename I>
      inline
      void
      height<I>::take(const argument& t)
      {
        min_level__ = mln::math::min(min_level__, t.v());
        max_level__ = mln::math::max(max_level__, t.v());
        height_ = max_level__ - min_level__;
      }

      template <typename I>
      inline
      void
      height<I>::take(const height<I>& other)
      {
        min_level__ = mln::math::min(min_level__, other.min_level__);
        max_level__ = mln::math::max(max_level__, other.max_level__);
        height_ = max_level__ - min_level__;
      }

      template <typename I>
      inline
      unsigned
      height<I>::to_result() const
      {
        return height_;
      }

      template <typename I>
      inline
      void
      height<I>::set_value(unsigned h)
      {
        height_ = h;
        // Reset the other members.
        min_level__ = mln_max(value);
        max_level__ = mln_min(value);
      }

      template <typename I>
      inline
      bool
      height<I>::is_valid() const
      {
        return true;
      }

    } // end of namespace mln::accu::shape

# endif // ! MLN_INCLUDE_ONLY

  } // end of namespace mln::accu

} // end of namespace mln


#endif // ! MLN_ACCU_SHAPE_HEIGHT_HH