Plugins/PMP/Scene_facegraph_item_k_ring_selection.h

#ifndef SCENE_FACEGRAPH_ITEM_K_RING_SELECTION_H
#define SCENE_FACEGRAPH_ITEM_K_RING_SELECTION_H
#include "Scene_facegraph_item_k_ring_selection_config.h"
#include "Scene_surface_mesh_item.h"
#include <CGAL/Three/Three.h>
#include <CGAL/iterator.h>
#include <set>
#include <CGAL/Qt/qglviewer.h>
#include <QKeyEvent>
#include <QMouseEvent>
#include <QMainWindow>
#include <QObject>
#include <CGAL/Three/Viewer_interface.h>

#include <map>
#include <queue>

#include <CGAL/boost/graph/selection.h>
#include <CGAL/Polygon_mesh_processing/connected_components.h>
#include <CGAL/Polygon_mesh_processing/border.h>
#include <CGAL/iterator.h>

#include <CGAL/Polygon_2.h>
typedef Scene_surface_mesh_item Scene_facegraph_item;
typedef EPICK FG_Traits;

typedef Scene_facegraph_item::Face_graph FaceGraph;
typedef boost::graph_traits<FaceGraph>::vertex_descriptor fg_vertex_descriptor;
typedef boost::graph_traits<FaceGraph>::edge_descriptor fg_edge_descriptor;
typedef boost::graph_traits<FaceGraph>::face_descriptor fg_face_descriptor;
typedef boost::graph_traits<FaceGraph>::halfedge_descriptor fg_halfedge_descriptor;

struct FG_is_selected_edge_property_map{
  typedef boost::property_map<FaceGraph,boost::edge_index_t>::type EImap;

  std::vector<bool>* is_selected_ptr;
  EImap* edge_index_map;
  FG_is_selected_edge_property_map()
    : is_selected_ptr(nullptr), edge_index_map(nullptr) {}
  FG_is_selected_edge_property_map(std::vector<bool>& is_selected, EImap* map)
    : is_selected_ptr( &is_selected), edge_index_map(map)
  {}

  std::size_t id(fg_edge_descriptor ed) {
    return get(*edge_index_map, ed);
  }

  friend bool get(FG_is_selected_edge_property_map map, fg_edge_descriptor ed)
  {
    CGAL_assertion(map.is_selected_ptr!=nullptr);
    return (*map.is_selected_ptr)[map.id(ed)];
  }

  friend void put(FG_is_selected_edge_property_map map, fg_edge_descriptor ed, bool b)
  {
    CGAL_assertion(map.is_selected_ptr!=nullptr);
    (*map.is_selected_ptr)[map.id(ed)]=b;
  }
};

inline CGAL::Three::Viewer_interface* getViewerUnderCursor()
{
  QWidget* widget = QApplication::widgetAt(QCursor::pos());
  CGAL::Three::Viewer_interface* viewer = qobject_cast<CGAL::Three::Viewer_interface*>(widget);
  if(!viewer)
    viewer = CGAL::Three::Three::activeViewer();
  return viewer;
}

class SCENE_FACEGRAPH_ITEM_K_RING_SELECTION_EXPORT Scene_facegraph_item_k_ring_selection
  : public QObject
{
  Q_OBJECT
public:
  struct Active_handle {
    enum Type{ VERTEX = 0, FACET = 1, EDGE = 2 , CONNECTED_COMPONENT = 3, PATH = 4};
  };

  typedef CGAL::Polygon_2<FG_Traits> Polygon_2;
  typedef std::vector<FG_Traits::Point_2> Polyline_2;
  typedef std::vector<Polyline_2> Polylines;

  // Hold mouse keyboard state together
  struct Mouse_keyboard_state
  {
    Mouse_keyboard_state() : shift_pressing(false), left_button_pressing(false) { }
    bool shift_pressing, left_button_pressing;
  };

  Mouse_keyboard_state  state;
  QMainWindow* mainwindow;
  Active_handle::Type    active_handle_type;
  int                    k_ring;
  Scene_facegraph_item* poly_item;
  bool is_active;
  bool is_current_selection;
  bool is_highlighting;

  Scene_facegraph_item_k_ring_selection() {}

  Scene_facegraph_item_k_ring_selection
    (Scene_facegraph_item* poly_item, QMainWindow* mw, Active_handle::Type aht, int k_ring)
      :is_active(false),is_current_selection(true), is_edit_mode(false)
  {
    init(poly_item, mw, aht, k_ring);
  }

  void setHighLighting(bool b)
  {
    cut_highlighting = !b;
  }
  void setEditMode(bool b)
  {
    is_edit_mode = b;
    Q_FOREACH(CGAL::QGLViewer* viewer,CGAL::QGLViewer::QGLViewerPool()){
      //for highlighting
      viewer->setMouseTracking(true);
    }
  }

  void init(Scene_facegraph_item* poly_item, QMainWindow* mw, Active_handle::Type aht,
            int k_ring) {
    this->poly_item = poly_item;
    this->active_handle_type = aht;
    this->k_ring = k_ring;
    polyline = new Polylines(0);
    polyline->push_back(Polyline_2());
    mainwindow = mw;
    is_highlighting = false;
    is_ready_to_highlight = true;
    cut_highlighting = false;
    is_ready_to_paint_select = true;
    is_lasso_active = false;

    Q_FOREACH(CGAL::QGLViewer* viewer,CGAL::QGLViewer::QGLViewerPool()){
      viewer->installEventFilter(this);
      viewer->setMouseBindingDescription(Qt::Key_D, Qt::ShiftModifier, Qt::LeftButton, "(When in selection plugin) Removes the clicked primitive from the selection. ");
    }
    mw->installEventFilter(this);
    connect(mw, SIGNAL(newViewerCreated(QObject*)),
            this, SLOT(connectNewViewer(QObject*)));
    connect(poly_item, SIGNAL(selected_vertex(void*)), this, SLOT(vertex_has_been_selected(void*)));
    connect(poly_item, SIGNAL(selected_facet(void*)), this, SLOT(facet_has_been_selected(void*)));
    connect(poly_item, SIGNAL(selected_edge(void*)), this, SLOT(edge_has_been_selected(void*)));
  }
  void setCurrentlySelected(bool b)
  {
    is_current_selection = b;
  }
  void set_lasso_mode(bool b) { is_lasso_active = b; }

public Q_SLOTS:
  // slots are called by signals of polyhedron_item
  void connectNewViewer(QObject* o)
  {
    o->installEventFilter(this);
  }
  void vertex_has_been_selected(void* void_ptr)
  {
    if((*CGAL::QGLViewer::QGLViewerPool().begin())->property("performing_selection").toBool())
      return;
    is_active=true;
    if(active_handle_type == Active_handle::VERTEX || active_handle_type == Active_handle::PATH)
    {
      typedef boost::graph_traits<FaceGraph>::vertices_size_type size_type;
      size_type h = static_cast<size_type>(reinterpret_cast<std::size_t>(void_ptr));
      process_selection( static_cast<fg_vertex_descriptor>(h) );
    }
    updateIsTreated();
  }
  void facet_has_been_selected(void* void_ptr)
  {
    if((*CGAL::QGLViewer::QGLViewerPool().begin())->property("performing_selection").toBool())
      return;
    is_active=true;
    if (active_handle_type == Active_handle::FACET
      || active_handle_type == Active_handle::CONNECTED_COMPONENT)
    {
      typedef boost::graph_traits<FaceGraph>::faces_size_type size_type;
      size_type h = static_cast<size_type>(reinterpret_cast<std::size_t>(void_ptr));
      process_selection( static_cast<fg_face_descriptor>(h) );
    }
    updateIsTreated();
  }
  void edge_has_been_selected(void* void_ptr)
  {
    if((*CGAL::QGLViewer::QGLViewerPool().begin())->property("performing_selection").toBool())
      return;
    is_active=true;
    if(active_handle_type == Active_handle::EDGE)
    {
      typedef boost::graph_traits<FaceGraph>::edges_size_type size_type;
      size_type h = static_cast<size_type>(reinterpret_cast<std::size_t>(void_ptr));
      process_selection( static_cast<fg_edge_descriptor>(h) );
    }
    updateIsTreated();
  }

  void paint_selection()
  {
    if(is_ready_to_paint_select)
    {
      const CGAL::qglviewer::Vec offset = CGAL::Three::Three::mainViewer()->offset();
      // paint with mouse move event
      CGAL::QGLViewer* viewer = CGAL::Three::Three::activeViewer();
      CGAL::qglviewer::Camera* camera = viewer->camera();
      viewer->makeCurrent();
      bool found = false;
      const CGAL::qglviewer::Vec& point = camera->pointUnderPixel(paint_pos, found) - offset;
      if(found)
      {
       CGAL::qglviewer::Vec orig;
       CGAL::qglviewer::Vec dir;
       if(camera->type() == CGAL::qglviewer::Camera::PERSPECTIVE)
       {
         orig = camera->position() - offset;
         dir = point - orig;
       }
       else
       {
         dir = camera->viewDirection();
         orig = CGAL::qglviewer::Vec(point.x - dir.x,
                                     point.y - dir.y,
                                     point.z - dir.z);

       }
        poly_item->select(orig.x, orig.y, orig.z, dir.x, dir.y, dir.z);
      }
      viewer->doneCurrent();
      is_ready_to_paint_select = false;
    }
  }

  void lasso_selection()
  {
    CGAL::QGLViewer* viewer = CGAL::Three::Three::activeViewer();
    const CGAL::qglviewer::Vec offset = CGAL::Three::Three::mainViewer()->offset();

    CGAL::qglviewer::Camera* camera = viewer->camera();
    const FaceGraph& poly = *poly_item->polyhedron();
    std::set<fg_face_descriptor> face_sel;
    boost::property_map<FaceGraph,CGAL::vertex_point_t>::const_type vpmap = get(boost::vertex_point, poly);
    //select all faces if their screen projection is inside the lasso
    for(fg_face_descriptor f : faces(poly))
    {
      for(fg_vertex_descriptor v : CGAL::vertices_around_face(halfedge(f, poly), poly))
      {
        FG_Traits::Point_3 p = get(vpmap, v);
        CGAL::qglviewer::Vec vp(p.x(), p.y(), p.z());
        CGAL::qglviewer::Vec vsp = camera->projectedCoordinatesOf(vp+offset);
        if(is_vertex_selected(vsp))
        {
          face_sel.insert(f);
          break;
        }
      }
    }
    if(face_sel.empty())
    {
      contour_2d.clear();
      qobject_cast<CGAL::Three::Viewer_interface*>(viewer)->set2DSelectionMode(false);
      return;
    }
    //get border edges of the selected patches
    std::vector<fg_halfedge_descriptor> boundary_edges;
    CGAL::Polygon_mesh_processing::border_halfedges(face_sel, poly, std::back_inserter(boundary_edges));
    std::vector<bool> mark(edges(poly).size(), false);
    boost::property_map<FaceGraph, boost::edge_index_t>::type edge_index
      = get(boost::edge_index, poly);
    FG_is_selected_edge_property_map spmap(mark, &edge_index);
    for(fg_halfedge_descriptor h : boundary_edges)
      put(spmap, edge(h, poly), true);

    boost::vector_property_map<int,
      boost::property_map<FaceGraph, boost::face_index_t>::type>
      fccmap(static_cast<unsigned>(num_faces(poly)));

    //get connected componant from the picked face
    std::set<fg_face_descriptor> final_sel;
    //std::vector<Polyhedron::Face_handle> cc;
    std::size_t nb_cc = CGAL::Polygon_mesh_processing::connected_components(poly
          , fccmap
          , CGAL::Polygon_mesh_processing::parameters::edge_is_constrained_map(spmap));
    std::vector<bool> is_cc_done(nb_cc, false);

    for(fg_face_descriptor f : face_sel)
    {
      int cc_id = get(fccmap, f);
      if(is_cc_done[cc_id])
      {
        continue;
      }
      CGAL::Halfedge_around_face_circulator<FaceGraph> hafc(halfedge(f, poly), poly);
      CGAL::Halfedge_around_face_circulator<FaceGraph> end = hafc;
      double x(0), y(0), z(0);
      int total(0);
      CGAL_For_all(hafc, end)
      {
        FG_Traits::Point_3 p = get(vpmap, target(*hafc, poly));
        x+=p.x(); y+=p.y(); z+=p.z();
        total++;
      }
      if(total == 0)
        continue;
      CGAL::qglviewer::Vec center(x/(double)total, y/(double)total, z/(double)total);
      CGAL::qglviewer::Vec orig;
      CGAL::qglviewer::Vec dir;
      if(camera->type() == CGAL::qglviewer::Camera::PERSPECTIVE)
      {
        orig = camera->position() - offset;
        dir = center - orig;
      }
      else
      {
        dir = camera->viewDirection();
        orig = CGAL::qglviewer::Vec(center.x - dir.x,
                                    center.y - dir.y,
                                    center.z - dir.z);
      }
      if(poly_item->intersect_face(orig.x,
                                   orig.y,
                                   orig.z,
                                   dir.x,
                                   dir.y,
                                   dir.z,
                                   f))
      {
        is_cc_done[cc_id] = true;
      }
    }
    for(fg_face_descriptor f : faces(poly))
    {
      if(is_cc_done[get(fccmap, f)])
        final_sel.insert(f);
    }
    switch(active_handle_type)
    {
    case Active_handle::FACET:
      selected(final_sel);
      break;
    case Active_handle::EDGE:
    {
      std::set<fg_edge_descriptor> e_sel;
      for(fg_face_descriptor f : final_sel)
      {
        for(fg_halfedge_descriptor h : CGAL::halfedges_around_face(halfedge(f, poly), poly))
        {
          FG_Traits::Point_3 p = get(vpmap, target(h, poly));
          CGAL::qglviewer::Vec vp1(p.x(), p.y(), p.z());
          CGAL::qglviewer::Vec vsp1 = camera->projectedCoordinatesOf(vp1+offset);
          p = get(vpmap, target(opposite(h, poly), poly));
          CGAL::qglviewer::Vec vp2(p.x(), p.y(), p.z());
          CGAL::qglviewer::Vec vsp2 = camera->projectedCoordinatesOf(vp2+offset);
          if(is_vertex_selected(vsp1) || is_vertex_selected(vsp2))
            e_sel.insert(edge(h, poly));
        }
      }
      selected(e_sel);
      break;
    }
    case Active_handle::VERTEX:
    {
      std::set<fg_vertex_descriptor> v_sel;
      for(fg_face_descriptor f : final_sel)
      {
        for(fg_vertex_descriptor v : CGAL::vertices_around_face(halfedge(f, poly), poly))
        {
          FG_Traits::Point_3 p = get(vpmap, v);
          CGAL::qglviewer::Vec vp(p.x(), p.y(), p.z());
          CGAL::qglviewer::Vec vsp = camera->projectedCoordinatesOf(vp+offset);
          if(is_vertex_selected(vsp))
            v_sel.insert(v);
        }
      }
      selected(v_sel);
      break;
    }
    default:
      break;
    }
    contour_2d.clear();
    Q_EMIT endSelection();
    qobject_cast<CGAL::Three::Viewer_interface*>(viewer)->set2DSelectionMode(false);
  }

  void highlight()
  {
    const CGAL::qglviewer::Vec offset = CGAL::Three::Three::mainViewer()->offset();
    if(is_ready_to_highlight)
    {
      // highlight with mouse move event
      CGAL::QGLViewer* viewer = getViewerUnderCursor();
      CGAL::qglviewer::Camera* camera = viewer->camera();
      viewer->makeCurrent();
      bool found = false;
      const CGAL::qglviewer::Vec& point = camera->pointUnderPixel(hl_pos, found) - offset;
      if(found)
      {
        CGAL::qglviewer::Vec orig;
        CGAL::qglviewer::Vec dir;
        if(camera->type() == CGAL::qglviewer::Camera::PERSPECTIVE)
        {
          orig = camera->position() - offset;
          dir = point - orig;
        }
        else
        {
          dir = camera->viewDirection();
          orig = CGAL::qglviewer::Vec(point.x - dir.x,
                                      point.y - dir.y,
                                      point.z - dir.z);

        }
        is_highlighting = true;
        poly_item->select(orig.x, orig.y, orig.z, dir.x, dir.y, dir.z);
        is_highlighting = false;
      }
      else
      {
        Q_EMIT clearHL();
      }
      is_ready_to_highlight = false;
    }
  }

Q_SIGNALS:
  void selected(const std::set<fg_vertex_descriptor>&);
  void selected(const std::set<fg_face_descriptor>&);
  void selected(const std::set<fg_edge_descriptor>&);
  void selected_HL(const std::set<fg_vertex_descriptor>&);
  void selected_HL(const std::set<fg_face_descriptor>&);
  void selected_HL(const std::set<fg_edge_descriptor>&);
  void toogle_insert(const bool);
  void endSelection();
  void resetIsTreated();
  void isCurrentlySelected(Scene_facegraph_item_k_ring_selection*);
  void clearHL();

protected:

  void updateIsTreated()
  {
    static ushort i = 0;
    i++;
    if(i==3)
    {
      i = 0;
      Q_EMIT resetIsTreated();
    }
  }
  template<class HandleType>
  void process_selection(HandleType clicked) {
    //keeps the highlighting on track if the brush_size is not 0
    int current_ring = 0;
    if(active_handle_type != Active_handle::PATH && !is_edit_mode)
      current_ring = k_ring;
    const std::set<HandleType>& selection = extract_k_ring(clicked, current_ring);
    if(is_highlighting)
    {
      Q_EMIT selected_HL(selection);
    }
    else
      Q_EMIT selected(selection);
  }

  template <class Handle>
  struct Is_selected_from_set{
    std::set<Handle>& selection;
    Is_selected_from_set(std::set<Handle>& selection)
      :selection(selection) {}
    friend bool get(Is_selected_from_set<Handle> map, Handle k)
    {
      return map.selection.count(k);
    }
    friend void put(Is_selected_from_set<Handle> map, Handle k, bool b)
    {
      if (b)
        map.selection.insert(k);
      else
        map.selection.erase(k);
    }
  };

  std::set<fg_vertex_descriptor>
  extract_k_ring(fg_vertex_descriptor clicked, unsigned int k)
  {
    std::set<fg_vertex_descriptor> selection;
    selection.insert(clicked);
    if (k>0)
      CGAL::expand_vertex_selection(CGAL::make_array(clicked),
                                    *poly_item->polyhedron(),
                                    k,
                                    Is_selected_from_set<fg_vertex_descriptor>(selection),
                                    CGAL::Emptyset_iterator());

    return selection;
  }

  std::set<fg_face_descriptor>
  extract_k_ring(fg_face_descriptor clicked, unsigned int k)
  {
    std::set<fg_face_descriptor> selection;
    selection.insert(clicked);
    if (k>0)
      CGAL::expand_face_selection(CGAL::make_array(clicked),
                                  *poly_item->polyhedron(),
                                  k,
                                  Is_selected_from_set<fg_face_descriptor>(selection),
                                  CGAL::Emptyset_iterator());

    return selection;
  }

  std::set<fg_edge_descriptor>
  extract_k_ring(fg_edge_descriptor clicked, unsigned int k)
  {
    std::set<fg_edge_descriptor> selection;
    selection.insert(clicked);

    if (k>0)
      CGAL::expand_edge_selection(CGAL::make_array(clicked),
                                  *poly_item->polyhedron(),
                                  k,
                                  Is_selected_from_set<fg_edge_descriptor>(selection),
                                  CGAL::Emptyset_iterator());
    return selection;
  }


  bool eventFilter(QObject* target, QEvent *event)
  {
    static QImage background;
    // This filter is both filtering events from 'viewer' and 'main window'

    // key events
      if(event->type() == QEvent::KeyPress || event->type() == QEvent::KeyRelease)  {
      QKeyEvent *keyEvent = static_cast<QKeyEvent*>(event);
      Qt::KeyboardModifiers modifiers = keyEvent->modifiers();

      state.shift_pressing = modifiers.testFlag(Qt::ShiftModifier);
    }

    if(event->type() == QEvent::KeyPress
            && state.shift_pressing
            && static_cast<QKeyEvent*>(event)->key()==Qt::Key_D)
    {
     Q_EMIT toogle_insert(false);
    }
    else if(event->type() == QEvent::KeyRelease
            && static_cast<QKeyEvent*>(event)->key()==Qt::Key_D)
    {
     Q_EMIT toogle_insert(true);
    }
    // mouse events
    if(event->type() == QEvent::MouseButtonPress || event->type() == QEvent::MouseButtonRelease) {
      QMouseEvent* mouse_event = static_cast<QMouseEvent*>(event);
      if(mouse_event->button() == Qt::LeftButton) {
        state.left_button_pressing = event->type() == QEvent::MouseButtonPress;
        if(is_edit_mode)
          Q_EMIT clearHL();
        if (!state.left_button_pressing)
        {
          if (is_active)
          {
            Q_EMIT endSelection();
            is_active=false;
          }
          apply_path();
          lasso_selection();
        }
      }
      //to avoid the contextual menu to mess up the states.
      else if(mouse_event->button() == Qt::RightButton) {
        state.left_button_pressing = false;
        state.shift_pressing = false;
      }
    }
    // use mouse move event for paint-like selection
    if( (event->type() == QEvent::MouseMove
         || (event->type() == QEvent::MouseButtonPress
             && static_cast<QMouseEvent*>(event)->button() == Qt::LeftButton))
        && (state.shift_pressing && state.left_button_pressing) )
    {
      Q_EMIT isCurrentlySelected(this);
      if(!is_current_selection)
        return false;
      if(target == mainwindow)
      {
        CGAL::QGLViewer* viewer = CGAL::Three::Three::activeViewer();
        viewer->setFocus();
        return false;
      }

      if(!is_lasso_active)
      {
        is_ready_to_paint_select = true;
        QMouseEvent* mouse_event = static_cast<QMouseEvent*>(event);
        hl_pos = mouse_event->pos();
        is_ready_to_highlight = !cut_highlighting;
        QTimer::singleShot(0, this, SLOT(highlight()));
        paint_pos = mouse_event->pos();
        if(!is_edit_mode || event->type() == QEvent::MouseButtonPress)
        {
          QTimer::singleShot(0,this,SLOT(paint_selection()));
        }
      }
      else
      {
        if (event->type() != QEvent::MouseMove)
        {
          //Create a QImage of the screen and paint the lasso on top of it
          CGAL::QGLViewer* viewer = CGAL::Three::Three::activeViewer();
          background = static_cast<CGAL::Three::Viewer_interface*>(viewer)->grabFramebuffer();
        }
        sample_mouse_path(background);
      }
    }
    //if the mouse is moving without left button pressed :
    // highlight the primitive under cursor
    else if(event->type() == QEvent::MouseMove && !state.left_button_pressing)
    {
      QMouseEvent* mouse_event = static_cast<QMouseEvent*>(event);
      CGAL::QGLViewer* viewer = getViewerUnderCursor();

      is_ready_to_highlight = !cut_highlighting;
      hl_pos = viewer->mapFromGlobal(mouse_event->globalPos());
      QTimer::singleShot(0, this, SLOT(highlight()));
    }//end MouseMove
    return false;
  }
  bool is_edit_mode;
  bool is_ready_to_highlight;
  bool is_ready_to_paint_select;
  bool is_lasso_active;
  QPoint hl_pos;
  QPoint paint_pos;
  Polyline_2 contour_2d;
  Polylines* polyline;
  Polyline_2& poly() const  { return polyline->front(); }
  Polygon_2 lasso;
  CGAL::Bbox_2 domain_rectangle;
  bool cut_highlighting;
  bool update_polyline () const
  {
    if (contour_2d.size() < 2 ||
        (!(poly().empty()) && contour_2d.back () == poly().back()))
      return false;


    if (!(poly().empty()) && contour_2d.back () == poly().back())
      return false;

    poly().clear();

    for (unsigned int i = 0; i < contour_2d.size (); ++ i)
      poly().push_back (contour_2d[i]);

    return true;
  }

  void sample_mouse_path(QImage& background)
  {
    CGAL::Three::Viewer_interface* viewer =
        qobject_cast<CGAL::Three::Viewer_interface*>(CGAL::Three::Three::activeViewer());
    viewer->makeCurrent();
    const QPoint& p = viewer->mapFromGlobal(QCursor::pos());
    contour_2d.push_back (FG_Traits::Point_2 (p.x(), p.y()));
    if (update_polyline ())
    {
      //update draw
      QPen pen;
      pen.setColor(QColor(Qt::green));
      pen.setWidth(3);

      //Create a QImage of the screen and paint the lasso on top of it
      QImage temp(background);
      QPainter *painter = new QPainter(&temp);


      //painter->begin(&image);
      painter->setPen(pen);
      for(std::size_t i=0; i<polyline->size(); ++i)
      {
        Polyline_2 poly = (*polyline)[i];
        if(!poly.empty())
          for(std::size_t j=0; j<poly.size()-1; ++j)
          {
            painter->drawLine(int(poly[j].x()),
                              int(poly[j].y()),
                              int(poly[j+1].x()),
                              int(poly[j+1].y()));
          }
      }
      painter->end();
      delete painter;
      viewer->set2DSelectionMode(true);
      viewer->setStaticImage(temp);
      viewer->update();
    }
  }

  void apply_path()
  {
    update_polyline ();
    domain_rectangle = CGAL::bbox_2 (contour_2d.begin (), contour_2d.end ());
    lasso = Polygon_2 (contour_2d.begin (), contour_2d.end ());
  }

  bool is_vertex_selected (CGAL::qglviewer::Vec& p)
  {
    if (domain_rectangle.xmin () < p.x &&
        p.x < domain_rectangle.xmax () &&
        domain_rectangle.ymin () < p.y &&
        p.y < domain_rectangle.ymax ())
      {
/*
 * domain_freeform.has_on_bounded_side() requires the polygon to be simple, which is never the case.
 * However, it works very well even if the polygon is not simple, so we use this instead to avoid
 * the cgal_assertion on is_simple().*/


        if (CGAL::bounded_side_2(lasso.container().begin(),
                                 lasso.container().end(),
                                 FG_Traits::Point_2(p.x, p.y),
                                 lasso.traits_member())  == CGAL::ON_BOUNDED_SIDE)
          return true;
      }
    return false;
  }
};
#endif