dpoints_pixter.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_CORE_DPOINTS_PIXTER_HH
# define MLN_CORE_DPOINTS_PIXTER_HH


# include <cassert>
# include <vector>

# include <mln/core/concept/proxy.hh>
# include <mln/core/concept/pixel_iterator.hh>
# include <mln/core/internal/pixel_impl.hh>
# include <mln/metal/converts_to.hh>


namespace mln
{

  /*------------------------.
  | dpoints_fwd_pixter<I>.  |
  `------------------------*/

  template <typename I>
  class dpoints_fwd_pixter
    : public Pixel_Iterator< dpoints_fwd_pixter<I> >,
      public internal::pixel_impl_< I, dpoints_fwd_pixter<I> >
  {
    typedef typename internal::pixel_impl_< I, dpoints_fwd_pixter<I> > super_;

  public:
    template <typename Dps, typename Pref>
    dpoints_fwd_pixter(I& image,
                       const Dps& dps,
                       const Pref& p_ref);

    template <typename Dps, typename Pref>
    dpoints_fwd_pixter(const Generalized_Pixel<Pref>& pxl_ref,
                       const Dps& dps);

    void start();
    void next_();

    void invalidate();
    bool is_valid() const;

    void update();

    const mln_value(I)& center_val() const;

  private:
    template <typename Dps>
    void init_(const Dps& dps);

  private:
    std::vector<int> offset_;
    typename std::vector<int>::const_iterator i_;

    mln_qlf_value(I)** value_ref_;
    const mln_psite(I)* p_ref_;
  };


  /*------------------------.
  | dpoints_bkd_pixter<I>.  |
  `------------------------*/

  template <typename I>
  class dpoints_bkd_pixter
    : public Pixel_Iterator< dpoints_bkd_pixter<I> >,
      public internal::pixel_impl_< I, dpoints_bkd_pixter<I> >
  {
    typedef typename internal::pixel_impl_< I, dpoints_bkd_pixter<I> > super_;

  public:
    template <typename Dps, typename Pref>
    dpoints_bkd_pixter(I& image,
                       const Dps& dps,
                       const Pref& p_ref);

    template <typename Dps, typename Pref>
    dpoints_bkd_pixter(const Generalized_Pixel<Pref>& pxl_ref,
                       const Dps& dps);

    void start();
    void next_();

    void invalidate();
    bool is_valid() const;

    void update();

    const mln_value(I)& center_val() const;

  private:
    template <typename Dps>
    void init_(const Dps& dps);

  private:
    std::vector<int> offset_;
    typename std::vector<int>::const_reverse_iterator i_;

    mln_qlf_value(I)** value_ref_;
    const mln_psite(I)* p_ref_;
  };



#ifndef MLN_INCLUDE_ONLY

  /*------------------------.
  | dpoints_fwd_pixter<I>.  |
  `------------------------*/

  template <typename I>
  template <typename Dps, typename Pref>
  inline
  dpoints_fwd_pixter<I>::dpoints_fwd_pixter(I& image,
                                            const Dps& dps,
                                            const Pref& p_ref)
    : super_(image)
  {
    mln_precondition(image.is_valid());

    mlc_converts_to(Pref, const mln_psite(I)&)::check();
    p_ref_ = & static_cast< const mln_psite(I)& >(p_ref);

    value_ref_ = 0;
    init_(dps);
  }

  template <typename I>
  template <typename Dps, typename Pref>
  inline
  dpoints_fwd_pixter<I>::dpoints_fwd_pixter(const Generalized_Pixel<Pref>& pxl_ref_,
                                            const Dps& dps)
    : super_(internal::force_exact<Pref>(pxl_ref_).ima())
  {
    const Pref& pxl_ref = internal::force_exact<Pref>(pxl_ref_);
    mln_precondition(pxl_ref.ima().is_valid());
    p_ref_ = 0;
    // Potential promotion from (T**) to (const T**) shall be forced.
    value_ref_ = const_cast<mln_qlf_value(I)**>(pxl_ref.address_());
    init_(dps);
  }

  template <typename I>
  inline
  const mln_value(I)&
  dpoints_fwd_pixter<I>::center_val() const
  {
    mln_invariant(value_ref_ != 0 || p_ref_ != 0);
    if (p_ref_)
      return image_(*p_ref_);
    else
      return **value_ref_;
  }

  template <typename I>
  template <typename Dps>
  inline
  void
  dpoints_fwd_pixter<I>::init_(const Dps& dps)
  {
    for (unsigned i = 0; i < dps.size(); ++i)
      offset_.push_back(this->image_.delta_index(dps.dp(i)));
    // offset_[0] is absolute
    // other offsets are relative:
    if (dps.size() > 1)
      for (unsigned i = dps.size() - 1; i > 0; --i)
        offset_[i] -= offset_[i - 1];
    invalidate();
  }

  template <typename I>
  inline
  void
  dpoints_fwd_pixter<I>::update()
  {
    if (is_valid())
      {
        if (p_ref_)
          this->value_ptr_ = & image_(*p_ref_) + *i_;
        else
          this->value_ptr_ = * value_ref_ + *i_;
      }
  }

  template <typename I>
  inline
  void
  dpoints_fwd_pixter<I>::start()
  {
    i_ = offset_.begin();
    update();
  }

  template <typename I>
  inline
  void
  dpoints_fwd_pixter<I>::next_()
  {
    ++i_;
    if (is_valid())
      this->value_ptr_ += *i_;
  }

  template <typename I>
  inline
  bool
  dpoints_fwd_pixter<I>::is_valid() const
  {
    return i_ != offset_.end();
  }

  template <typename I>
  inline
  void
  dpoints_fwd_pixter<I>::invalidate()
  {
    i_ = offset_.end();
  }


  /*------------------------.
  | dpoints_bkd_pixter<I>.  |
  `------------------------*/

  template <typename I>
  template <typename Dps, typename Pref>
  inline
  dpoints_bkd_pixter<I>::dpoints_bkd_pixter(I& image,
                                            const Dps& dps,
                                            const Pref& p_ref)
    : super_(image)
  {
    mln_precondition(image.is_valid());
    internal::get_adr(p_ref_, p_ref);
    value_ref_ = 0;
    init_(dps);
  }

  template <typename I>
  template <typename Dps, typename Pref>
  inline
  dpoints_bkd_pixter<I>::dpoints_bkd_pixter(const Generalized_Pixel<Pref>& pxl_ref_,
                                            const Dps& dps)
    : super_(internal::force_exact<Pref>(pxl_ref_).ima())
  {
    const Pref& pxl_ref = internal::force_exact<Pref>(pxl_ref_);
    mln_precondition(pxl_ref.ima().is_valid());
    p_ref_ = 0;
    // Potential promotion from (T**) to (const T**) shall be forced.
    value_ref_ = const_cast<mln_qlf_value(I)**>(pxl_ref.address_());
    init_(dps);
  }

  template <typename I>
  inline
  const mln_value(I)&
  dpoints_bkd_pixter<I>::center_val() const
  {
    mln_invariant(value_ref_ != 0 || p_ref_ != 0);
    if (p_ref_)
      return image_(*p_ref_);
    else
      return **value_ref_;
  }

  template <typename I>
  template <typename Dps>
  inline
  void
  dpoints_bkd_pixter<I>::init_(const Dps& dps)
  {
    for (unsigned i = 0; i < dps.size(); ++i)
      offset_.push_back(this->image_.delta_index(dps.dp(i)));
    // offset_[size() - 1] is absolute
    // other offsets are relative:
    if (dps.size() > 1)
      for (unsigned i = 0; i < dps.size() - 1; ++i)
        offset_[i] -= offset_[i + 1];
    invalidate();
  }

  template <typename I>
  inline
  void
  dpoints_bkd_pixter<I>::update()
  {
    if (is_valid())
      {
        if (p_ref_)
          this->value_ptr_ = & image_(*p_ref_) + *i_;
        else
          this->value_ptr_ = * value_ref_ + *i_;
      }
  }

  template <typename I>
  inline
  void
  dpoints_bkd_pixter<I>::start()
  {
    i_ = offset_.rbegin();
    update();
  }

  template <typename I>
  inline
  void
  dpoints_bkd_pixter<I>::next_()
  {
    ++i_;
    if (is_valid())
      this->value_ptr_ += *i_;
  }

  template <typename I>
  inline
  bool
  dpoints_bkd_pixter<I>::is_valid() const
  {
    return i_ != offset_.rend();
  }

  template <typename I>
  inline
  void
  dpoints_bkd_pixter<I>::invalidate()
  {
    i_ = offset_.rend();
  }

#endif // ! MLN_INCLUDE_ONLY

} // end of namespace mln


#endif // ! MLN_CORE_DPOINTS_PIXTER_HH