cgal/Polygon/include/CGAL/General_polygon_with_holes_2.h

// Copyright (c) 2005
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// and Tel-Aviv University (Israel).  All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL$
// $Id$
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s): Baruch Zukerman <baruchzu@post.tau.ac.il>
//            Efi Fogel <efifogel@gmail.com>

#ifndef CGAL_GENERAL_POLYGON_WITH_HOLES_2_H
#define CGAL_GENERAL_POLYGON_WITH_HOLES_2_H

#include <deque>
#include <iostream>
#include <CGAL/IO/io.h>

namespace CGAL {

/*! \ingroup PkgPolygon2Ref
 *
 * The class `General_polygon_with_holes_2` models the concept
 * `GeneralPolygonWithHoles_2`. It represents a general polygon with holes.
 * It is parameterized with a type `Polygon_` used to define the exposed
 * type `%Polygon_2`. This type represents the outer boundary of the general
 * polygon and each hole.
 *
 * \tparam Polygon_ must have input and output operators.
 *
 * \cgalModels{GeneralPolygonWithHoles_2}
 */
template <typename Polygon_>
class General_polygon_with_holes_2 {
public:
/// \name Definition

/// @{
  /// polygon without hole type
  typedef Polygon_                                    Polygon_2;
#ifndef DOXYGEN_RUNNING
  // Backward compatibility
  typedef Polygon_2                                   General_polygon_2;
#endif
/// @}

  typedef std::deque<Polygon_2>                       Holes_container;

  typedef typename Holes_container::iterator          Hole_iterator;
  typedef typename Holes_container::const_iterator    Hole_const_iterator;

  typedef unsigned int                                Size;

  General_polygon_with_holes_2() = default;


  explicit General_polygon_with_holes_2(const Polygon_2& pgn_boundary) :
    m_pgn(pgn_boundary)
  {}

  explicit General_polygon_with_holes_2(Polygon_2&& pgn_boundary) :
    m_pgn(std::move(pgn_boundary))
  {}

  template <typename HolesInputIterator>
  General_polygon_with_holes_2(const Polygon_2& pgn_boundary,
                               HolesInputIterator h_begin,
                               HolesInputIterator h_end) :
    m_pgn(pgn_boundary),
    m_holes(h_begin, h_end)
  {}

  template <typename HolesInputIterator>
  General_polygon_with_holes_2(Polygon_2&& pgn_boundary,
                               HolesInputIterator h_begin,
                               HolesInputIterator h_end) :
    m_pgn(std::move(pgn_boundary)),
    m_holes(h_begin, h_end)
  {}

  Holes_container& holes() { return m_holes; }

  const Holes_container& holes() const { return m_holes; }

  Hole_iterator holes_begin() { return m_holes.begin(); }

  Hole_iterator holes_end() { return m_holes.end(); }

  Hole_const_iterator holes_begin() const { return m_holes.begin(); }

  Hole_const_iterator holes_end() const { return m_holes.end(); }

  bool is_unbounded() const { return m_pgn.is_empty(); }

  Polygon_2& outer_boundary() { return m_pgn; }

  const Polygon_2& outer_boundary() const { return m_pgn; }

  void add_hole(const Polygon_2& pgn_hole) { m_holes.push_back(pgn_hole); }

  void add_hole(Polygon_2&& pgn_hole) { m_holes.emplace_back(std::move(pgn_hole)); }

  void erase_hole(Hole_iterator hit) { m_holes.erase(hit); }

  void clear_outer_boundary() { m_pgn.clear(); }

  void clear_holes() { m_holes.clear(); }

  bool has_holes() const { return (!m_holes.empty()); }

  Size number_of_holes() const { return static_cast<Size>(m_holes.size()); }

  void clear() {
    m_pgn.clear();
    m_holes.clear();
  }

  bool is_plane() const { return (m_pgn.is_empty() && m_holes.empty()); }

  bool is_empty() const
  {
    if(! outer_boundary().is_empty()) {
        return false;
      }
    for(const auto& h : holes()){
      if(! h.is_empty()){
        return false;
      }
    }
    return true;
  }

protected:
  Polygon_2 m_pgn;
  Holes_container m_holes;
};

//-----------------------------------------------------------------------//
//                          operator<<
//-----------------------------------------------------------------------//
/*!
This operator exports a `General_polygon_with_holes_2` to the output stream `os`.

An \ascii and a binary format exist. The format can be selected with
the \cgal modifiers for streams, `CGAL::IO::set_ascii_mode()` and `CGAL::IO::set_binary_mode()`,
respectively. The modifier `CGAL::IO::set_pretty_mode()` can be used to allow for (a
few) structuring comments in the output. Otherwise, the output would
be free of comments. The default for writing is \ascii without comments.

The number of curves of the outer boundary is exported followed by the
curves themselves. Then, the number of holes
is exported, and for each hole, the number of curves on its outer
boundary is exported followed by the curves themselves.

\relates General_polygon_with_holes_2
*/
template <typename Polygon_>
std::ostream&
operator<<(std::ostream& os, const General_polygon_with_holes_2<Polygon_>& p) {
  typename General_polygon_with_holes_2<Polygon_>::Hole_const_iterator hit;

  switch(IO::get_mode(os)) {
    case IO::ASCII :
      os << p.outer_boundary() << ' ' << p.number_of_holes()<< ' ';
      for (hit = p.holes_begin(); hit != p.holes_end(); ++hit) {
        os << *hit << ' ';
      }
      return os;

    case IO::BINARY :
      os << p.outer_boundary()  << p.number_of_holes();
      for (hit = p.holes_begin(); hit != p.holes_end(); ++hit) {
        os << *hit;
      }
      return os;


    default:
      os << "General_polygon_with_holes_2( " << std::endl;
      os << p.outer_boundary() << " " << p.number_of_holes()<< " ";
      for (hit = p.holes_begin(); hit != p.holes_end(); ++hit) {
        os << *hit << " )";
      }
      return os;
  }
}

//-----------------------------------------------------------------------//
//                          operator>>
//-----------------------------------------------------------------------//

/*!
This operator imports a `General_polygon_with_holes_2` from the input stream `is`.

Both \ascii and binary formats are supported, and the format is automatically detected.

The format consists of the number of curves of the outer boundary
followed by the curves themselves, followed
by the number of holes, and for each hole, the number of curves on its
outer boundary is followed by the curves themselves.

\relates General_polygon_with_holes_2
*/
template <typename Polygon_>
std::istream&
operator>>(std::istream& is, General_polygon_with_holes_2<Polygon_>& p) {
  p.clear();
  is >> p.outer_boundary();

  unsigned int n_holes;
  is >> n_holes;
  if (is) {
    Polygon_ pgn_hole;
    for (unsigned int i=0; i<n_holes; ++i) {
      is >> pgn_hole;
      p.add_hole(std::move(pgn_hole));
    }
  }

  return is;
}


} //namespace CGAL

#endif