#include "Scene_polyhedron_item.h"
#include <CGAL/Three/Viewer_interface.h>

#ifndef Q_MOC_RUN
#include <CGAL/intersections.h>
#include "Kernel_type.h"
#include <CGAL/IO/File_writer_wavefront.h>
#include <CGAL/IO/generic_copy_OFF.h>
#include <CGAL/IO/OBJ_reader.h>

#include <CGAL/AABB_tree.h>
#include <CGAL/AABB_traits.h>
#include <CGAL/Polyhedron_items_with_id_3.h>
#include <CGAL/Polygon_mesh_processing/compute_normal.h>
#include <CGAL/Polygon_mesh_processing/connected_components.h>
#include <CGAL/Polygon_mesh_processing/measure.h>
#include <CGAL/Polygon_mesh_processing/self_intersections.h>
#include <CGAL/Polygon_mesh_processing/polygon_soup_to_polygon_mesh.h>
#include <CGAL/Polygon_mesh_processing/orient_polygon_soup.h>
#include <CGAL/boost/graph/selection.h>
#include <CGAL/property_map.h>
#include <CGAL/statistics_helpers.h>

#include <list>
#include <iostream>
#include <limits>
#endif // Q_MOC_RUN

#include <QVariant>
#include <QDebug>
#include <QDialog>
#include <QApplication>
#include <QInputDialog>
#include <QMessageBox>
#include <QObject>
#include <QMenu>
#include <QAction>

#ifndef Q_MOC_RUN
#include <boost/foreach.hpp>
#include "triangulate_primitive.h"
#include "Color_map.h"
#include "id_printing.h"
#endif // Q_MOC_RUN

namespace PMP = CGAL::Polygon_mesh_processing;
typedef Polyhedron::Traits Traits;
typedef Polyhedron::Facet Facet;
typedef Polyhedron::Traits	                           Kernel;
typedef Kernel::Point_3	                                   Point;
typedef Kernel::Vector_3	                           Vector;
typedef Polyhedron::Halfedge_around_facet_circulator       HF_circulator;
typedef boost::graph_traits<Polyhedron>::face_descriptor   face_descriptor;
//Used to triangulate the AABB_Tree
class Primitive
{
public:
  // types
  typedef Polyhedron::Facet_iterator Id; // Id type
  typedef Kernel::Point_3 Point; // point type
  typedef Kernel::Triangle_3 Datum; // datum type

private:
  // member data
  Id m_it; // iterator
  Datum m_datum; // 3D triangle

  // constructor
public:
  Primitive() {}
  Primitive(Datum triangle, Id it)
    : m_it(it), m_datum(triangle)
  {
  }
public:
  Id& id() { return m_it; }
  const Id& id() const { return m_it; }
  Datum& datum() { return m_datum; }
  const Datum& datum() const { return m_datum; }

  /// Returns a point on the primitive
  Point reference_point() const { return m_datum.vertex(0); }
};
typedef CGAL::AABB_traits<Kernel, Primitive> AABB_traits;
typedef CGAL::AABB_tree<AABB_traits> Input_facets_AABB_tree;

struct Scene_polyhedron_item_priv{
  typedef Polyhedron::Facet_iterator Facet_iterator;
  typedef std::vector<QColor> Color_vector;
  Scene_polyhedron_item_priv(Scene_polyhedron_item* item)
    : item(item), poly(new Polyhedron)
  {
    init_default_values();
  }
  Scene_polyhedron_item_priv(const Polyhedron& poly_, Scene_polyhedron_item* item)
    : item(item), poly(new Polyhedron(poly_))
  {
    init_default_values();
  }

  Scene_polyhedron_item_priv(Polyhedron* const poly_, Scene_polyhedron_item* item)
    : item(item), poly(poly_)
  {
    init_default_values();
  }
  ~Scene_polyhedron_item_priv()
  {
    delete poly;
    BOOST_FOREACH(TextItem* it, targeted_id)
      delete it;
  }

  void init_default_values() {
    program = NULL;
    show_only_feature_edges_m = false;
    show_feature_edges_m = false;
    facet_picking_m = false;
    erase_next_picked_facet_m = false;
    plugin_has_set_color_vector_m = false;
    nb_facets = 0;
    nb_lines = 0;
    nb_f_lines = 0;
    is_multicolor = false;
    no_flat = false;
    vertices_displayed = false;
    edges_displayed = false;
    faces_displayed = false;
    face_idx_buffer = QOpenGLBuffer(QOpenGLBuffer::IndexBuffer);
    face_idx_buffer.create();
    edge_idx_buffer = QOpenGLBuffer(QOpenGLBuffer::IndexBuffer);
    edge_idx_buffer.create();
    f_edge_idx_buffer = QOpenGLBuffer(QOpenGLBuffer::IndexBuffer);
    f_edge_idx_buffer.create();
    invalidate_stats();
    CGAL::set_halfedgeds_items_id(*poly);
  }


  void compute_normals_and_vertices(const bool is_recent,
                                    const bool colors_only = false,
                                    const bool draw_two_sides = false) const;

  bool isFacetConvex(Facet_iterator, const Polyhedron::Traits::Vector_3&)const;

  void triangulate_convex_facet(Facet_iterator,
                                const bool, const bool, const bool is_recent)const;

  void triangulate_facet(Scene_polyhedron_item::Facet_iterator,
                         const Traits::Vector_3& normal,
                         const bool colors_only,
                         const bool draw_two_sides,
                         const bool is_recent) const;
  void init();
  void invalidate_stats();
  void* get_aabb_tree();
  QList<Kernel::Triangle_3> triangulate_primitive(Polyhedron::Facet_iterator fit,
                                                  Traits::Vector_3 normal);
  Color_vector colors_;
  bool show_only_feature_edges_m;
  bool show_feature_edges_m;
  bool facet_picking_m;
  bool erase_next_picked_facet_m;
  bool no_flat;
  //the following variable is used to indicate if the color vector must not be automatically updated.
  // If this boolean is true, the item's color will be independant of the color's wheel, if it is false
  // changing the color in the wheel will change the color of the item, even if it is multicolor.
  bool plugin_has_set_color_vector_m;
  bool is_multicolor;
  void killIds();
  void fillTargetedIds(const Polyhedron::Facet_handle& selected_fh,
                       const Kernel::Point_3 &point_under,
                       CGAL::Three::Viewer_interface *viewer,
                       const CGAL::qglviewer::Vec &offset);
  Scene_polyhedron_item* item;
  Polyhedron *poly;
  double volume, area;
  QVector<QColor> colors;
  mutable std::vector<float> positions_lines;
  mutable std::vector<unsigned int> idx_lines;
  mutable std::vector<unsigned int> idx_feature_lines;
  mutable std::vector<unsigned int> idx_faces;
  mutable std::vector<float> positions_facets;
  mutable std::vector<float> normals_gouraud;
  mutable std::vector<float> normals_flat;
  mutable std::vector<float> color_facets;
  mutable std::size_t nb_facets;
  mutable std::size_t nb_lines;
  mutable std::size_t nb_f_lines;
  mutable QOpenGLShaderProgram *program;
  mutable QOpenGLBuffer face_idx_buffer;
  mutable QOpenGLBuffer edge_idx_buffer;
  mutable QOpenGLBuffer f_edge_idx_buffer;
  
  unsigned int number_of_null_length_edges;
  unsigned int number_of_degenerated_faces;
  int genus;
  bool self_intersect;
  int m_min_patch_id; // the min value of the patch ids initialized in init()
  mutable bool vertices_displayed;
  mutable bool edges_displayed;
  mutable bool faces_displayed;
  mutable QList<double> text_ids;
  mutable std::vector<TextItem*> targeted_id;
  void initialize_buffers(CGAL::Three::Viewer_interface *viewer = 0) const;
  enum VAOs {
    Facets=0,
    Edges,
    Feature_edges,
    Gouraud_Facets,
    NbOfVaos
  };
  enum VBOs {
    Facets_vertices = 0,
    Facets_color,
    Edges_vertices,
    Feature_edges_vertices,
    Edges_color,
    Facets_normals_gouraud,
    Facets_normals_flat,
    NbOfVbos
  };
  TextListItem* textVItems;
  TextListItem* textEItems;
  TextListItem* textFItems;
  // Initialization
};



const char* aabb_property_name = "Scene_polyhedron_item aabb tree";


QList<Kernel::Triangle_3> Scene_polyhedron_item_priv::triangulate_primitive(Polyhedron::Facet_iterator fit,
                                                Traits::Vector_3 normal)
{
  typedef FacetTriangulator<Polyhedron, Polyhedron::Traits, boost::graph_traits<Polyhedron>::vertex_descriptor> FT;
  //The output list
  QList<Kernel::Triangle_3> res;
  //check if normal contains NaN values
  if (normal.x() != normal.x() || normal.y() != normal.y() || normal.z() != normal.z())
  {
    qDebug()<<"Warning in triangulation of the selection item: normal contains NaN values and is not valid.";
    return QList<Kernel::Triangle_3>();
  }
  double diagonal;
  if(item->diagonalBbox() != std::numeric_limits<double>::infinity())
    diagonal = item->diagonalBbox();
  else
    diagonal = 0.0;
  FT triangulation(fit,normal,poly,diagonal);
  //iterates on the internal faces to add the vertices to the positions
  //and the normals to the appropriate vectors
  for( FT::CDT::Finite_faces_iterator
      ffit = triangulation.cdt->finite_faces_begin(),
      end = triangulation.cdt->finite_faces_end();
      ffit != end; ++ffit)
  {
    if(ffit->info().is_external)
      continue;


    res << Kernel::Triangle_3(ffit->vertex(0)->point(),
                              ffit->vertex(1)->point(),
                              ffit->vertex(2)->point());

  }
  return res;
}



void* Scene_polyhedron_item_priv::get_aabb_tree()
{
  QVariant aabb_tree_property = item->property(aabb_property_name);
  if(aabb_tree_property.isValid()) {
    void* ptr = aabb_tree_property.value<void*>();
    return static_cast<Input_facets_AABB_tree*>(ptr);
  }
  else {
    QApplication::setOverrideCursor(Qt::WaitCursor);
    Polyhedron* poly = item->polyhedron();
    if(poly) {

      Input_facets_AABB_tree* tree =
          new Input_facets_AABB_tree();
      typedef Polyhedron::Traits	    Kernel;
      int index =0;
      BOOST_FOREACH( Polyhedron::Facet_iterator f, faces(*poly))
      {
        if (CGAL::is_degenerate_triangle_face(f, *poly, get(CGAL::vertex_point, *poly), Kernel()))
          continue;
        if(!f->is_triangle())
        {
          Traits::Vector_3 normal = f->plane().orthogonal_vector(); //initialized in compute_normals_and_vertices
          index +=3;
          Q_FOREACH(Kernel::Triangle_3 triangle, triangulate_primitive(f,normal))
          {
            Primitive primitive(triangle, f);
            tree->insert(primitive);
          }
        }
        else
        {
          Kernel::Triangle_3 triangle(
                f->halfedge()->vertex()->point(),
                f->halfedge()->next()->vertex()->point(),
                f->halfedge()->next()->next()->vertex()->point()
                );
          Primitive primitive(triangle, f);
          tree->insert(primitive);
        }
      }
      item->setProperty(aabb_property_name,
                        QVariant::fromValue<void*>(tree));
      QApplication::restoreOverrideCursor();
      return tree;
    }
    else return 0;
  }
}

void delete_aabb_tree(Scene_polyhedron_item* item)
{
    QVariant aabb_tree_property = item->property(aabb_property_name);
    if(aabb_tree_property.isValid()) {
        void* ptr = aabb_tree_property.value<void*>();
        Input_facets_AABB_tree* tree = static_cast<Input_facets_AABB_tree*>(ptr);
        if(tree) {
            delete tree;
            tree = 0;
        }
        item->setProperty(aabb_property_name, QVariant());
    }
}

template<typename TypeWithXYZ, typename ContainerWithPushBack>
void push_back_xyz(const TypeWithXYZ& t,
                   ContainerWithPushBack& vector)
{
  vector.push_back(t.x());
  vector.push_back(t.y());
  vector.push_back(t.z());
}


template<typename TypeWithRGB, typename ContainerWithPushBack>
void push_back_rgb(const TypeWithRGB& t,
                   ContainerWithPushBack& vector)
{
  vector.push_back(t.redF());
  vector.push_back(t.greenF());
  vector.push_back(t.blueF());
}

bool Scene_polyhedron_item_priv::isFacetConvex(Facet_iterator f, const Polyhedron::Traits::Vector_3& N) const
{
  typedef Polyhedron::Traits::Vector_3 Vector;
  typedef Polyhedron::Traits::Orientation Orientation;
  Orientation orientation;
  Vector normal = N;
  Facet::Halfedge_around_facet_circulator
          he = f->facet_begin(),
          he_end(he);
  bool normal_is_ok;
  do{
    normal_is_ok = true;

    //Initializes the facet orientation

    Polyhedron::Traits::Point_3 S,T;
    S = source(he, *poly)->point();
    T = target(he, *poly)->point();
    Vector V1 = Vector((T-S).x(), (T-S).y(), (T-S).z());
    S = source(he->next(), *poly)->point();
    T = target(he->next(), *poly)->point();
    Vector V2 = Vector((T-S).x(), (T-S).y(), (T-S).z());

    if(normal == Vector(0,0,0))
      normal_is_ok = false;
    if(normal_is_ok)
    {
      orientation = Polyhedron::Traits::Orientation_3()(V1, V2, normal);
      if( orientation == CGAL::COPLANAR )
        normal_is_ok = false;
    }
    //Checks if the normal is good : if the normal is null
    // or if it is coplanar to the facet, we need another one.
    if(!normal_is_ok)
    {
      normal = CGAL::cross_product(V1,V2);
    }

  }while( ++he != he_end && !normal_is_ok);
  //if no good normal can be found, stop here.
  if (!normal_is_ok)
    return false;

  //computes convexness

  //re-initializes he_end;
  he = f->facet_begin(),
  he_end = he;
  do
  {
    Polyhedron::Traits::Point_3 S,T;
    S = source(he, *poly)->point();
    T = target(he, *poly)->point();
    Vector V1 = Vector((T-S).x(), (T-S).y(), (T-S).z());
    S = source(he->next(), *poly)->point();
    T = target(he->next(), *poly)->point();
    Vector V2 = Vector((T-S).x(), (T-S).y(), (T-S).z());
    Orientation res = Polyhedron::Traits::Orientation_3()(V1, V2, normal) ;

    if(res!= orientation && res != CGAL::ZERO)
      return false;
  }while( ++he != he_end);
  return true;
}

void Scene_polyhedron_item_priv::triangulate_convex_facet(Facet_iterator f,
                                                          const bool colors_only,
                                                          const bool draw_two_sides,
                                                          const bool is_recent)const
{
  const CGAL::qglviewer::Vec v_offset = static_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first())->offset();
  Vector offset = Vector(v_offset.x, v_offset.y, v_offset.z);
  Polyhedron::Traits::Point_3 p0,p1,p2;
  Facet::Halfedge_around_facet_circulator
      he = f->facet_begin(),
      he_end(he);
  const int this_patch_id = f->patch_id();
  while( next(he, *poly) != prev(he_end, *poly))
  {
    ++he;
    if (is_multicolor)
    {
      for (int i = 0; i<3; ++i)
      {
        color_facets.push_back(colors_[this_patch_id-m_min_patch_id].redF());
        color_facets.push_back(colors_[this_patch_id-m_min_patch_id].greenF());
        color_facets.push_back(colors_[this_patch_id-m_min_patch_id].blueF());

        color_facets.push_back(colors_[this_patch_id-m_min_patch_id].redF());
        color_facets.push_back(colors_[this_patch_id-m_min_patch_id].greenF());
        color_facets.push_back(colors_[this_patch_id-m_min_patch_id].blueF());
      }
    }
    if (colors_only)
      continue;


    p0 = he_end->vertex()->point();
    p1 = he->vertex()->point();
    p2 = next(he, *poly)->vertex()->point();

    idx_faces.push_back(static_cast<unsigned int>(he_end->vertex()->id()));
    idx_faces.push_back(static_cast<unsigned int>(he->vertex()->id()));
    idx_faces.push_back(static_cast<unsigned int>(next(he, *poly)->vertex()->id()));

    if(is_multicolor || !no_flat || !is_recent )
    {
      push_back_xyz(p0+offset, positions_facets);
      push_back_xyz(p1+offset, positions_facets);
      push_back_xyz(p2+offset, positions_facets);
    }
    if(!draw_two_sides)
    {
      push_back_xyz(f->plane().orthogonal_vector(), normals_flat);
      push_back_xyz(f->plane().orthogonal_vector(), normals_flat);
      push_back_xyz(f->plane().orthogonal_vector(), normals_flat);
    }
  }


}
//Make sure all the facets are triangles
void
Scene_polyhedron_item_priv::triangulate_facet(Scene_polyhedron_item::Facet_iterator fit,
                                         const Traits::Vector_3& normal,
                                         const bool colors_only,
                                         const bool draw_two_sides,
                                         const bool is_recent) const


{
  typedef FacetTriangulator<Polyhedron, Polyhedron::Traits, boost::graph_traits<Polyhedron>::vertex_descriptor> FT;
  const CGAL::qglviewer::Vec v_offset = static_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first())->offset();
  Vector offset = Vector(v_offset.x, v_offset.y, v_offset.z);
  double diagonal;
  if(item->diagonalBbox() != std::numeric_limits<double>::infinity())
    diagonal = item->diagonalBbox();
  else
    diagonal = 0.0;
  FT triangulation(fit,normal,poly,diagonal,offset);

  if(triangulation.cdt->dimension() != 2 )
  {
    qDebug()<<"Warning : cdt not right. Facet not displayed";
    return;
  }

  //iterates on the internal faces to add the vertices to the positions
  //and the normals to the appropriate vectors
  const int this_patch_id = fit->patch_id();
  for(FT::CDT::Finite_faces_iterator
      ffit = triangulation.cdt->finite_faces_begin(),
      end = triangulation.cdt->finite_faces_end();
      ffit != end; ++ffit)
  {
    if(ffit->info().is_external)
      continue;

    if (is_multicolor)
    {
     for (int i = 0; i<3; ++i)
     {
      push_back_rgb(colors_[this_patch_id-m_min_patch_id], color_facets);
     }
    }
    if (colors_only)
     continue;

    idx_faces.push_back(static_cast<unsigned int>(triangulation.v2v[ffit->vertex(0)]->id()));
    idx_faces.push_back(static_cast<unsigned int>(triangulation.v2v[ffit->vertex(1)]->id()));
    idx_faces.push_back(static_cast<unsigned int>(triangulation.v2v[ffit->vertex(2)]->id()));

    if(is_multicolor || !no_flat || !is_recent)
    {
      push_back_xyz(ffit->vertex(0)->point(), positions_facets);
      push_back_xyz(ffit->vertex(1)->point(), positions_facets);
      push_back_xyz(ffit->vertex(2)->point(), positions_facets);
      if(!draw_two_sides)
      {
        push_back_xyz(normal, normals_flat);
        push_back_xyz(normal, normals_flat);
        push_back_xyz(normal, normals_flat);
      }
    }
  }
}



void
Scene_polyhedron_item_priv::initialize_buffers(CGAL::Three::Viewer_interface* viewer) const
{
    //vao containing the data for the facets
    if((!viewer->isOpenGL_4_3() && !no_flat )|| is_multicolor)
    {
      //flat
      if(viewer->property("draw_two_sides").toBool())
      {
        program = item->getShaderProgram(Scene_polyhedron_item::PROGRAM_OLD_FLAT, viewer);
      }
      else
      {
        program = item->getShaderProgram(Scene_polyhedron_item::PROGRAM_WITH_LIGHT, viewer);
      }
    }
  program = item->getShaderProgram(Scene_polyhedron_item::PROGRAM_WITH_LIGHT, viewer);
  program->bind();
  //gouraud
  item->vaos[Gouraud_Facets]->bind();
  item->buffers[Edges_vertices].bind();
  item->buffers[Edges_vertices].allocate(positions_lines.data(),
                                         static_cast<int>(positions_lines.size()*sizeof(float)));
  program->enableAttributeArray("vertex");
  program->setAttributeBuffer("vertex",GL_FLOAT,0,3);
  item->buffers[Edges_vertices].release();
  face_idx_buffer.bind();
  face_idx_buffer.allocate(idx_faces.data(),
                      static_cast<int>(idx_faces.size()*sizeof(unsigned int)));
  face_idx_buffer.release();
  

  item->buffers[Facets_normals_gouraud].bind();
  item->buffers[Facets_normals_gouraud].allocate(normals_gouraud.data(),
                                                 static_cast<int>(normals_gouraud.size()*sizeof(float)));
  program->enableAttributeArray("normals");
  program->setAttributeBuffer("normals",GL_FLOAT,0,3);
  item->buffers[Facets_normals_gouraud].release();
  if(is_multicolor)
  {
    item->buffers[Facets_color].bind();
    item->buffers[Facets_color].allocate(color_facets.data(),
                                                static_cast<int>(color_facets.size()*sizeof(float)));
    program->enableAttributeArray("colors");
    program->setAttributeBuffer("colors",GL_FLOAT,0,3);
    item->buffers[Facets_color].release();
  }
  else
  {
    program->disableAttributeArray("colors");
  }
  item->vaos[Gouraud_Facets]->release();
  program->release();
  if(viewer->isOpenGL_4_3() && !is_multicolor)
  {
    //modern flat
    program = item->getShaderProgram(Scene_polyhedron_item::PROGRAM_FLAT, viewer);
    program->bind();
    item->vaos[Gouraud_Facets]->bind();
    item->buffers[Edges_vertices].bind();
    program->enableAttributeArray("vertex");
    program->setAttributeBuffer("vertex",GL_FLOAT,0,3);
    item->buffers[Edges_vertices].release();
    if(is_multicolor)
    {
      item->buffers[Facets_color].bind();
      program->enableAttributeArray("colors");
      program->setAttributeBuffer("colors",GL_FLOAT,0,3);
      item->buffers[Facets_color].release();
    }
    else
    {
      program->disableAttributeArray("colors");
    }
    item->vaos[Gouraud_Facets]->release();
    program->release();
  }
  //vao containing the data for the lines
  {
    program = item->getShaderProgram(Scene_polyhedron_item::PROGRAM_WITHOUT_LIGHT, viewer);
    program->bind();
    item->vaos[Edges]->bind();

    item->buffers[Edges_vertices].bind();
    program->enableAttributeArray("vertex");
    program->setAttributeBuffer("vertex",GL_FLOAT,0,3);
    item->buffers[Edges_vertices].release();
    edge_idx_buffer.bind();
    edge_idx_buffer.allocate(idx_lines.data(),
                        static_cast<int>(idx_lines.size()*sizeof(unsigned int)));
    edge_idx_buffer.release();

    program->disableAttributeArray("colors");
    program->release();

    item->vaos[Edges]->release();

  }
  //vao containing the data for the feature_edges
  {
    program = item->getShaderProgram(Scene_polyhedron_item::PROGRAM_NO_SELECTION, viewer);
    program->bind();
    item->vaos[Feature_edges]->bind();

    item->buffers[Edges_vertices].bind();
    program->enableAttributeArray("vertex");
    program->setAttributeBuffer("vertex",GL_FLOAT,0,3);
    item->buffers[Edges_vertices].release();
    
    f_edge_idx_buffer.bind();
    f_edge_idx_buffer.allocate(idx_feature_lines.data(),
                       static_cast<int>(idx_feature_lines.size()*sizeof(unsigned int)));
    f_edge_idx_buffer.release();
    program->disableAttributeArray("colors");
    program->release();

    item->vaos[Feature_edges]->release();

  }
  nb_lines = positions_lines.size();
  positions_lines.resize(0);
  positions_lines.shrink_to_fit();
  nb_facets = positions_facets.size();
  positions_facets.resize(0);
  positions_facets.shrink_to_fit();

  color_facets.resize(0);
  color_facets.shrink_to_fit();
  normals_gouraud.resize(0);
  normals_gouraud.shrink_to_fit();
  normals_flat.resize(0);
  normals_flat.shrink_to_fit();


  if (viewer->hasText())
    viewer->updateIds(item);
  item->are_buffers_filled = true;
}

void
Scene_polyhedron_item_priv::compute_normals_and_vertices(const bool is_recent,
                                                         const bool colors_only,
                                                         const bool draw_two_sides) const
{
  bool add_flat_data = is_multicolor || (!is_recent || !no_flat);
  const CGAL::qglviewer::Vec v_offset = static_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first())->offset();

    QApplication::setOverrideCursor(Qt::WaitCursor);
    positions_facets.resize(0);
    positions_lines.resize(0);
    normals_gouraud.resize(0);
    normals_flat.resize(0);
    color_facets.resize(0);
    idx_faces.resize(0);
    idx_lines.resize(0);
    idx_feature_lines.resize(0);

    //Facets
    typedef Polyhedron::Traits	    Kernel;
    typedef Kernel::Point_3	    Point;
    typedef Kernel::Vector_3	    Vector;
    typedef Polyhedron::Facet_iterator Facet_iterator;
    typedef Polyhedron::Halfedge_around_facet_circulator HF_circulator;
    typedef boost::graph_traits<Polyhedron>::face_descriptor   face_descriptor;
    typedef boost::graph_traits<Polyhedron>::vertex_descriptor vertex_descriptor;
    Vector offset = Vector(v_offset.x, v_offset.y, v_offset.z);

    CGAL::Unique_hash_map<face_descriptor, Vector> face_normals_map;
    boost::associative_property_map<CGAL::Unique_hash_map<face_descriptor, Vector> >
      nf_pmap(face_normals_map);
    CGAL::Unique_hash_map<vertex_descriptor, Vector> vertex_normals_map;
    boost::associative_property_map< CGAL::Unique_hash_map<vertex_descriptor, Vector> >
      nv_pmap(vertex_normals_map);

    PMP::compute_normals(*poly, nv_pmap, nf_pmap);

    Facet_iterator f = poly->facets_begin();
    for(f = poly->facets_begin();
        f != poly->facets_end();
        f++)
    {
      if (f == boost::graph_traits<Polyhedron>::null_face())
        continue;
      Vector nf = get(nf_pmap, f);
      f->plane() = Kernel::Plane_3(f->halfedge()->vertex()->point(), nf);
      if(is_triangle(f->halfedge(),*poly))
      {
          const int this_patch_id = f->patch_id();
          HF_circulator he = f->facet_begin();
          HF_circulator end = he;
          CGAL_For_all(he,end)
          {
            if (add_flat_data && item->isItemMulticolor())
            {
              color_facets.push_back(colors_[this_patch_id-m_min_patch_id].redF());
              color_facets.push_back(colors_[this_patch_id-m_min_patch_id].greenF());
              color_facets.push_back(colors_[this_patch_id-m_min_patch_id].blueF());
            }
            if (colors_only)
              continue;

            const Point& p = he->vertex()->point();

            // If Flat shading:1 normal per polygon added once per vertex
            if(add_flat_data)
            {
              push_back_xyz(p+offset, positions_facets);
              if(!draw_two_sides)
                push_back_xyz(nf, normals_flat);
            }

            idx_faces.push_back(static_cast<unsigned int>(he->vertex()->id()));
         }
      }
      else if (is_quad(f->halfedge(), *poly))
      {
        if (item->isItemMulticolor())
        {
          const int this_patch_id = f->patch_id();
          for (unsigned int i = 0; i < 6; ++i)
          { //6 "halfedges" for the quad, because it is 2 triangles
            color_facets.push_back(colors_[this_patch_id-m_min_patch_id].redF());
            color_facets.push_back(colors_[this_patch_id-m_min_patch_id].greenF());
            color_facets.push_back(colors_[this_patch_id-m_min_patch_id].blueF());
          }
        }
        if (colors_only)
          continue;

        //1st half-quad

        idx_faces.push_back(static_cast<unsigned int>(f->halfedge()->vertex()->id()));
        idx_faces.push_back(static_cast<unsigned int>(f->halfedge()->next()->vertex()->id()));
        idx_faces.push_back(static_cast<unsigned int>(f->halfedge()->next()->next()->vertex()->id()));
        if(add_flat_data)
        {
          Point p0 = f->halfedge()->vertex()->point();
          Point p1 = f->halfedge()->next()->vertex()->point();
          Point p2 = f->halfedge()->next()->next()->vertex()->point();
          push_back_xyz(p0+offset, positions_facets);
          push_back_xyz(p1+offset, positions_facets);
          push_back_xyz(p2+offset, positions_facets);
          if(!draw_two_sides)
          {
            push_back_xyz(nf, normals_flat);
            push_back_xyz(nf, normals_flat);
            push_back_xyz(nf, normals_flat);
          }
        }
        //2nd half-quad
        idx_faces.push_back(static_cast<unsigned int>(f->halfedge()->next()->next()->vertex()->id()));
        idx_faces.push_back(static_cast<unsigned int>(f->halfedge()->prev()->vertex()->id()));
        idx_faces.push_back(static_cast<unsigned int>(f->halfedge()->vertex()->id()));

        if(add_flat_data)
        {
          Point p0 = f->halfedge()->next()->next()->vertex()->point();
          Point p1 = f->halfedge()->prev()->vertex()->point();
          Point p2 = f->halfedge()->vertex()->point();

          push_back_xyz(p0+offset, positions_facets);
          push_back_xyz(p1+offset, positions_facets);
          push_back_xyz(p2+offset, positions_facets);
          if(!draw_two_sides)
          {
            push_back_xyz(nf, normals_flat);
            push_back_xyz(nf, normals_flat);
            push_back_xyz(nf, normals_flat);
          }
        }
      }
      else
      {
        if(isFacetConvex(f, nf))
        {
          triangulate_convex_facet(f, colors_only, draw_two_sides, is_recent);
        }
        else
        {
          this->triangulate_facet(f, nf, colors_only, draw_two_sides, is_recent);
        }
      }

    }
    //Lines
    typedef Kernel::Point_3		Point;
    typedef Polyhedron::Vertex_iterator	Vertex_iterator;
    for(Vertex_iterator vit = poly->vertices_begin();
        vit != poly->vertices_end();
        vit++)
    {
      Point p = vit->point();
      push_back_xyz(p+offset, positions_lines);
      //// If Gouraud shading: 1 normal per vertex
      Vector nv = get(nv_pmap, vit);
      push_back_xyz(nv, normals_gouraud);
    }

    typedef Polyhedron::Edge_iterator	Edge_iterator;
    Edge_iterator he;

    for(he = poly->edges_begin();
        he != poly->edges_end();
        he++)
    {
        if ( he->is_feature_edge())
        {
          if (colors_only)
            continue;

          idx_feature_lines.push_back(static_cast<unsigned int>(he->vertex()->id()));
          idx_feature_lines.push_back(static_cast<unsigned int>(he->opposite()->vertex()->id()));
        }
        else
        {
          if (colors_only)
            continue;

          idx_lines.push_back(static_cast<unsigned int>(he->vertex()->id()));
          idx_lines.push_back(static_cast<unsigned int>(he->opposite()->vertex()->id()));
        }
    }
    QApplication::restoreOverrideCursor();
}

Scene_polyhedron_item::Scene_polyhedron_item()
    : Scene_item(Scene_polyhedron_item_priv::NbOfVbos,Scene_polyhedron_item_priv::NbOfVaos),
      d(new Scene_polyhedron_item_priv(this))
{
    cur_shading=FlatPlusEdges;
    is_selected = true;
    d->textVItems = new TextListItem(this);
    d->textEItems = new TextListItem(this);
    d->textFItems = new TextListItem(this);

}

Scene_polyhedron_item::Scene_polyhedron_item(Polyhedron* const p)
    : Scene_item(Scene_polyhedron_item_priv::NbOfVbos,Scene_polyhedron_item_priv::NbOfVaos),
      d(new Scene_polyhedron_item_priv(p,this))
{
    cur_shading=FlatPlusEdges;
    is_selected = true;
    d->textVItems = new TextListItem(this);
    d->textEItems = new TextListItem(this);
    d->textFItems = new TextListItem(this);
}

Scene_polyhedron_item::Scene_polyhedron_item(const Polyhedron& p)
    : Scene_item(Scene_polyhedron_item_priv::NbOfVbos,Scene_polyhedron_item_priv::NbOfVaos),
      d(new Scene_polyhedron_item_priv(p,this))
{
    cur_shading=FlatPlusEdges;
    is_selected=true;
    d->textVItems = new TextListItem(this);
    d->textEItems = new TextListItem(this);
    d->textFItems = new TextListItem(this);
}

Scene_polyhedron_item::~Scene_polyhedron_item()
{
    delete_aabb_tree(this);
    CGAL::QGLViewer* viewer = *CGAL::QGLViewer::QGLViewerPool().begin();
    if(viewer)
    {
      CGAL::Three::Viewer_interface* v = qobject_cast<CGAL::Three::Viewer_interface*>(viewer);

      //Clears the targeted Id
      if(d)
      {
        BOOST_FOREACH(TextItem* item, d->targeted_id)
            v->textRenderer()->removeText(item);
      }
      //Remove vertices textitems
      if(d->textVItems)
      {
        v->textRenderer()->removeTextList(d->textVItems);
        delete d->textVItems;
        d->textVItems=NULL;
      }
      //Remove edges textitems
      if(d->textEItems)
      {
        v->textRenderer()->removeTextList(d->textEItems);
        delete d->textEItems;
        d->textEItems=NULL;
      }
      //Remove faces textitems
      if(d->textFItems)
      {
        v->textRenderer()->removeTextList(d->textFItems);
        delete d->textFItems;
        d->textFItems=NULL;
      }
    }
    if(d)
    {
      delete d;
      d=NULL;
    }
}


void
Scene_polyhedron_item_priv::
init()
{
  typedef Polyhedron::Facet_iterator Facet_iterator;

  if ( !plugin_has_set_color_vector_m )
  {
    // Fill indices map and get max subdomain value
    int max = 0;
    int min = (std::numeric_limits<int>::max)();
    for(Facet_iterator fit = poly->facets_begin(), end = poly->facets_end() ;
        fit != end; ++fit)
    {
      max = (std::max)(max, fit->patch_id());
      min = (std::min)(min, fit->patch_id());
    }

    colors_.clear();
    compute_color_map(item->color(), (std::max)(0, max + 1 - min),
                      std::back_inserter(colors_));
    m_min_patch_id=min;
  }
  else
    m_min_patch_id=0;
  invalidate_stats();
}

void
Scene_polyhedron_item_priv::
invalidate_stats()
{
  number_of_degenerated_faces = (unsigned int)(-1);
  number_of_null_length_edges = (unsigned int)(-1);
  volume = -std::numeric_limits<double>::infinity();
  area = -std::numeric_limits<double>::infinity();
  self_intersect = false;
  genus = -1;
}

//vertex_index is the storage for selection
Scene_polyhedron_item::Vertex_selection_map 
Scene_polyhedron_item::vertex_selection_map()
{
  return get(boost::vertex_index,*d->poly);
}
//face_index is the storage for selection
Scene_polyhedron_item::Face_selection_map 
Scene_polyhedron_item::face_selection_map()
{
  return get(boost::face_index,*d->poly);
}

Scene_polyhedron_item*
Scene_polyhedron_item::clone() const {
    return new Scene_polyhedron_item(*(d->poly));}

// Load polyhedron from .OFF file
bool
Scene_polyhedron_item::load(std::istream& in)
{


    in >> *(d->poly);

    if ( in && !isEmpty() )
    {
        invalidateOpenGLBuffers();
        return true;
    }
    return false;
}
// Load polyhedron from .obj file
bool
Scene_polyhedron_item::load_obj(std::istream& in)
{
  typedef Polyhedron::Vertex::Point Point;
  std::vector<Point> points;
  std::vector<std::vector<std::size_t> > faces;
  bool failed = !CGAL::read_OBJ(in,points,faces);

  CGAL::Polygon_mesh_processing::orient_polygon_soup(points,faces);
  CGAL::Polygon_mesh_processing::polygon_soup_to_polygon_mesh( points,faces,*(d->poly));
  if ( (! failed) && !isEmpty() )
  {
    invalidateOpenGLBuffers();
    return true;
  }
  return false;
}

// Write polyhedron to .OFF file
bool
Scene_polyhedron_item::save(std::ostream& out) const
{
  QApplication::setOverrideCursor(Qt::WaitCursor);
  out.precision(17);
    out << *(d->poly);
    QApplication::restoreOverrideCursor();
    return (bool) out;
}

bool
Scene_polyhedron_item::save_obj(std::ostream& out) const
{
  CGAL::File_writer_wavefront  writer;
  CGAL::generic_print_polyhedron(out, *(d->poly), writer);
  return out.good();
}


QString
Scene_polyhedron_item::toolTip() const
{
    if(!d->poly)
        return QString();

  QString str =
         QObject::tr("<p>Polyhedron_3 <b>%1</b> (mode: %5, color: %6)</p>"
                       "<p>Number of vertices: %2<br />"
                       "Number of edges: %3<br />"
                     "Number of faces: %4")
            .arg(this->name())
            .arg(d->poly->size_of_vertices())
            .arg(d->poly->size_of_halfedges()/2)
            .arg(d->poly->size_of_facets())
            .arg(this->renderingModeName())
            .arg(this->color().name());
  str += QString("<br />Number of isolated vertices: %1<br />").arg(getNbIsolatedvertices());
  return str;
}

QMenu* Scene_polyhedron_item::contextMenu()
{
  const char* prop_name = "Menu modified by Scene_polyhedron_item.";

  QMenu* menu = Scene_item::contextMenu();

  QAction* actionResetColor=
      menu->findChild<QAction*>(tr("actionResetColor"));

  if(isItemMulticolor())
  {
    if(!actionResetColor)
    {
      actionResetColor = menu->addAction(tr("Reset Colors"));
      actionResetColor->setObjectName("actionResetColor");
    }
    connect(actionResetColor, SIGNAL(triggered()),
            this, SLOT(resetColors()));
  }
  else if(actionResetColor)
  {
    menu->removeAction(actionResetColor);
    actionResetColor->deleteLater();
  }


  // Use dynamic properties:
  // http://doc.qt.io/qt-5/qobject.html#property
  bool menuChanged = menu->property(prop_name).toBool();

  if(!menuChanged) {
    menu->addSeparator();
    QAction* actionPrintVertices=
        menu->addAction(tr("Display Vertices Ids"));
    actionPrintVertices->setCheckable(true);
    actionPrintVertices->setObjectName("actionPrintVertices");
    connect(actionPrintVertices, SIGNAL(triggered(bool)),
            this, SLOT(showVertices(bool)));

    QAction* actionPrintEdges=
        menu->addAction(tr("Display Edges Ids"));
    actionPrintEdges->setCheckable(true);
    actionPrintEdges->setObjectName("actionPrintEdges");
    connect(actionPrintEdges, SIGNAL(triggered(bool)),
            this, SLOT(showEdges(bool)));

    QAction* actionPrintFaces=
        menu->addAction(tr("Display Faces Ids"));
    actionPrintFaces->setCheckable(true);
    actionPrintFaces->setObjectName("actionPrintFaces");
    connect(actionPrintFaces, SIGNAL(triggered(bool)),
            this, SLOT(showFaces(bool)));

    QAction* actionZoomToId=
        menu->addAction(tr("Zoom to Index"));
    actionZoomToId->setObjectName("actionZoomToId");
    connect(actionZoomToId, &QAction::triggered,
            this, &Scene_polyhedron_item::zoomToId);

    menu->addSeparator();

    QAction* actionShowOnlyFeatureEdges =
        menu->addAction(tr("Show Only &Feature Edges"));
    actionShowOnlyFeatureEdges->setCheckable(true);
    actionShowOnlyFeatureEdges->setChecked(d->show_only_feature_edges_m);
    actionShowOnlyFeatureEdges->setObjectName("actionShowOnlyFeatureEdges");
    connect(actionShowOnlyFeatureEdges, SIGNAL(toggled(bool)),
            this, SLOT(show_only_feature_edges(bool)));

    QAction* actionShowFeatureEdges =
        menu->addAction(tr("Show Feature Edges"));
    actionShowFeatureEdges->setCheckable(true);
    actionShowFeatureEdges->setChecked(d->show_feature_edges_m);
    actionShowFeatureEdges->setObjectName("actionShowFeatureEdges");
    connect(actionShowFeatureEdges, SIGNAL(toggled(bool)),
            this, SLOT(show_feature_edges(bool)));

    QAction* actionPickFacets =
        menu->addAction(tr("Facets Picking"));
    actionPickFacets->setCheckable(true);
    actionPickFacets->setObjectName("actionPickFacets");
    connect(actionPickFacets, SIGNAL(toggled(bool)),
            this, SLOT(enable_facets_picking(bool)));

    QAction* actionEraseNextFacet =
        menu->addAction(tr("Erase Next Picked Facet"));
    actionEraseNextFacet->setCheckable(true);
    actionEraseNextFacet->setObjectName("actionEraseNextFacet");
    connect(actionEraseNextFacet, SIGNAL(toggled(bool)),
            this, SLOT(set_erase_next_picked_facet(bool)));
    if(! static_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first())->isOpenGL_4_3())
    {
      QAction* actionDisableFlatShading=
          menu->addAction(tr("Disable Flat Shading"));
      actionDisableFlatShading->setCheckable(true);
      actionDisableFlatShading->setObjectName("actionDisableFlatShading");
      connect(actionDisableFlatShading, SIGNAL(toggled(bool)),
              this, SLOT(set_flat_disabled(bool)));
    }
    menu->setProperty(prop_name, true);
  }

  QAction* action = menu->findChild<QAction*>("actionShowOnlyFeatureEdges");
  if(action) action->setChecked(d->show_only_feature_edges_m);
  action = menu->findChild<QAction*>("actionShowFeatureEdges");
  if(action) action->setChecked(d->show_feature_edges_m);
  action = menu->findChild<QAction*>("actionPickFacets");
  if(action) action->setChecked(d->facet_picking_m);
  action = menu->findChild<QAction*>("actionEraseNextFacet");
  if(action) action->setChecked(d->erase_next_picked_facet_m);
  action = menu->findChild<QAction*>("actionPrintVertices");
  if(action) action->setChecked(d->vertices_displayed);
  action = menu->findChild<QAction*>("actionPrintEdges");
  if(action) action->setChecked(d->edges_displayed);
  action = menu->findChild<QAction*>("actionPrintFaces");
  if(action) action->setChecked(d->faces_displayed);

  return menu;
}
void Scene_polyhedron_item::show_only_feature_edges(bool b)
{
    d->show_only_feature_edges_m = b;
    invalidateOpenGLBuffers();
    Q_EMIT itemChanged();
}

void Scene_polyhedron_item::show_feature_edges(bool b)
{
  d->show_feature_edges_m = b;
  invalidateOpenGLBuffers();
  Q_EMIT itemChanged();
}

void Scene_polyhedron_item::enable_facets_picking(bool b)
{
    d->facet_picking_m = b;
}

void Scene_polyhedron_item::set_erase_next_picked_facet(bool b)
{
    if(b) { d->facet_picking_m = true; } // automatically activate facet_picking
    d->erase_next_picked_facet_m = b;
}

void Scene_polyhedron_item::draw(CGAL::Three::Viewer_interface* viewer) const {
    if(!are_buffers_filled)
    {
        d->compute_normals_and_vertices(viewer->isOpenGL_4_3(),
                                        false,
                                        viewer->property("draw_two_sides").toBool());
        d->initialize_buffers(viewer);
        compute_bbox();
    }

    if(!d->is_multicolor && viewer->isOpenGL_4_3() &&
       (renderingMode() == Flat || renderingMode() == FlatPlusEdges))
    {
        vaos[Scene_polyhedron_item_priv::Gouraud_Facets]->bind();
        attribBuffers(viewer, PROGRAM_FLAT);
        d->program = getShaderProgram(PROGRAM_FLAT);
        d->program->bind();
        if(!d->is_multicolor)
        {
                d->program->setAttributeValue("colors", this->color());
        }
        if(is_selected)
                d->program->setUniformValue("is_selected", true);
        else
                d->program->setUniformValue("is_selected", false);
        d->face_idx_buffer.bind();
        viewer->glDrawElements(GL_TRIANGLES, static_cast<GLuint>(d->idx_faces.size()),
                               GL_UNSIGNED_INT, 0);
        d->face_idx_buffer.release();
        d->program->release();
        vaos[Scene_polyhedron_item_priv::Gouraud_Facets]->release();
    }
    else if((d->is_multicolor || !viewer->isOpenGL_4_3()) &&
            (renderingMode() == Flat || renderingMode() == FlatPlusEdges))
    {
      vaos[Scene_polyhedron_item_priv::Facets]->bind();
      if(viewer->property("draw_two_sides").toBool())
      {
        attribBuffers(viewer, PROGRAM_OLD_FLAT);
        d->program = getShaderProgram(PROGRAM_OLD_FLAT);
      }
      else
      {
        attribBuffers(viewer, PROGRAM_WITH_LIGHT);
        d->program = getShaderProgram(PROGRAM_WITH_LIGHT);
      }
      d->program->bind();
      if(!d->is_multicolor)
      {
        d->program->setAttributeValue("colors", this->color());
      }
      if(is_selected)
        d->program->setUniformValue("is_selected", true);
      else
        d->program->setUniformValue("is_selected", false);
      viewer->glDrawArrays(GL_TRIANGLES, 0, static_cast<GLsizei>(d->nb_facets/3));
      d->program->release();
      vaos[Scene_polyhedron_item_priv::Facets]->release();
    }
    else
    {
        vaos[Scene_polyhedron_item_priv::Gouraud_Facets]->bind();
        attribBuffers(viewer, PROGRAM_WITH_LIGHT);
        d->program = getShaderProgram(PROGRAM_WITH_LIGHT);
        d->program->bind();
        if(!d->is_multicolor)
        {
                d->program->setAttributeValue("colors", this->color());
        }
        if(is_selected)
                d->program->setUniformValue("is_selected", true);
        else
                d->program->setUniformValue("is_selected", false);
        d->face_idx_buffer.bind();
        viewer->glDrawElements(GL_TRIANGLES, static_cast<GLuint>(d->idx_faces.size()),
                               GL_UNSIGNED_INT, 0);
        d->face_idx_buffer.release();
        d->program->release();
        vaos[Scene_polyhedron_item_priv::Gouraud_Facets]->release();
    }
}

// Points/Wireframe/Flat/Gouraud OpenGL drawing in a display list
void Scene_polyhedron_item::drawEdges(CGAL::Three::Viewer_interface* viewer) const
{
    if (!are_buffers_filled)
    {
        d->compute_normals_and_vertices(viewer->isOpenGL_4_3(), false,
                                        viewer->property("draw_two_sides").toBool());
        d->initialize_buffers(viewer);
        compute_bbox();
    }

    if(!d->show_only_feature_edges_m)
    {
        vaos[Scene_polyhedron_item_priv::Edges]->bind();

        attribBuffers(viewer, PROGRAM_WITHOUT_LIGHT);
        d->program = getShaderProgram(PROGRAM_WITHOUT_LIGHT);
        d->program->bind();
        //draw the edges
        d->program->setAttributeValue("colors", this->color().lighter(50));
        if(is_selected)
          d->program->setUniformValue("is_selected", true);
        else
          d->program->setUniformValue("is_selected", false);
        d->edge_idx_buffer.bind();
        viewer->glDrawElements(GL_LINES, static_cast<GLuint>(d->idx_lines.size()),
                               GL_UNSIGNED_INT, 0);
        d->edge_idx_buffer.release();
        d->program->release();
        vaos[Scene_polyhedron_item_priv::Edges]->release();
    }

    //draw the feature edges
    vaos[Scene_polyhedron_item_priv::Feature_edges]->bind();
    attribBuffers(viewer, PROGRAM_NO_SELECTION);
    d->program = getShaderProgram(PROGRAM_NO_SELECTION);
    d->program->bind();
    if(d->show_feature_edges_m || d->show_only_feature_edges_m)
        d->program->setAttributeValue("colors", Qt::red);
    else
    {
        if(!is_selected)
            d->program->setAttributeValue("colors", this->color().lighter(50));
        else
            d->program->setAttributeValue("colors",QColor(0,0,0));
    }
    d->f_edge_idx_buffer.bind();
    viewer->glDrawElements(GL_LINES, static_cast<GLuint>(d->idx_feature_lines.size()),
                           GL_UNSIGNED_INT, d->idx_feature_lines.data());
    d->f_edge_idx_buffer.release();
    d->program->release();
    vaos[Scene_polyhedron_item_priv::Feature_edges]->release();
    }

void
Scene_polyhedron_item::drawPoints(CGAL::Three::Viewer_interface* viewer) const {
    if(!are_buffers_filled)
    {
        d->compute_normals_and_vertices(viewer->isOpenGL_4_3(), false, viewer->property("draw_two_sides").toBool());
        d->initialize_buffers(viewer);
        compute_bbox();
    }

    vaos[Scene_polyhedron_item_priv::Edges]->bind();
    attribBuffers(viewer, PROGRAM_WITHOUT_LIGHT);
    d->program = getShaderProgram(PROGRAM_WITHOUT_LIGHT);
    d->program->bind();
    //draw the points
    d->program->setAttributeValue("colors", this->color());
    viewer->glDrawArrays(GL_POINTS, 0, static_cast<GLsizei>(d->nb_lines/3));
    // Clean-up
    d->program->release();
    vaos[Scene_polyhedron_item_priv::Edges]->release();
}

Polyhedron*
Scene_polyhedron_item::polyhedron()       { return d->poly; }
const Polyhedron*
Scene_polyhedron_item::polyhedron() const { return d->poly; }

bool
Scene_polyhedron_item::isEmpty() const {
    return (d->poly == 0) || d->poly->empty();
}

void Scene_polyhedron_item::compute_bbox() const {
    const Kernel::Point_3& p = *(d->poly->points_begin());
    CGAL::Bbox_3 bbox(p.x(), p.y(), p.z(), p.x(), p.y(), p.z());
    for(Polyhedron::Point_iterator it = d->poly->points_begin();
        it != d->poly->points_end();
        ++it) {
        bbox = bbox + it->bbox();
    }
    _bbox = Bbox(bbox.xmin(),bbox.ymin(),bbox.zmin(),
                bbox.xmax(),bbox.ymax(),bbox.zmax());
}


void
Scene_polyhedron_item::
invalidateOpenGLBuffers()
{
  CGAL::set_halfedgeds_items_id(*(d->poly));
  Q_EMIT item_is_about_to_be_changed();
    delete_aabb_tree(this);
    d->init();
    Base::invalidateOpenGLBuffers();
    are_buffers_filled = false;
    is_bbox_computed = false;
    d->invalidate_stats();
    d->killIds();
}

void
Scene_polyhedron_item::selection_changed(bool p_is_selected)
{
    if(p_is_selected != is_selected)
    {
        is_selected = p_is_selected;
    }
}

void
Scene_polyhedron_item::setColor(QColor c)
{
  // reset patch ids
  if (d->colors_.size()>2 || d->plugin_has_set_color_vector_m)
  {
    d->colors_.clear();
    d->is_multicolor = false;
  }
  Scene_item::setColor(c);
  if(d->is_multicolor)
    invalidateOpenGLBuffers();
}

void
Scene_polyhedron_item::select(double orig_x,
                              double orig_y,
                              double orig_z,
                              double dir_x,
                              double dir_y,
                              double dir_z)
{

    void* vertex_to_emit = 0;
    if(d->facet_picking_m)
    {
        typedef Input_facets_AABB_tree Tree;
        typedef Tree::Object_and_primitive_id Object_and_primitive_id;

        Tree* aabb_tree = static_cast<Tree*>(d->get_aabb_tree());
        if(aabb_tree)
        {
            const Kernel::Point_3 ray_origin(orig_x, orig_y, orig_z);
            const Kernel::Vector_3 ray_dir(dir_x, dir_y, dir_z);
            const Kernel::Ray_3 ray(ray_origin, ray_dir);
            typedef std::list<Object_and_primitive_id> Intersections;
            Intersections intersections;
            aabb_tree->all_intersections(ray, std::back_inserter(intersections));
            Intersections::iterator closest = intersections.begin();
            if(closest != intersections.end())
            {
                const Kernel::Point_3* closest_point =
                        CGAL::object_cast<Kernel::Point_3>(&closest->first);
                for(Intersections::iterator
                    it = boost::next(intersections.begin()),
                    end = intersections.end();
                    it != end; ++it)
                {
                    if(! closest_point) {
                        closest = it;
                    }
                    else {
                        const Kernel::Point_3* it_point =
                                CGAL::object_cast<Kernel::Point_3>(&it->first);
                        if(it_point &&
                                (ray_dir * (*it_point - *closest_point)) < 0)
                        {
                            closest = it;
                            closest_point = it_point;
                        }
                    }
                }
                if(closest_point) {
                    Polyhedron::Facet_handle selected_fh = closest->second;

                    // The computation of the nearest vertex may be costly.  Only
                    // do it if some objects are connected to the signal
                    // 'selected_vertex'.
                    if(QObject::receivers(SIGNAL(selected_vertex(void*))) > 0)
                    {
                        Polyhedron::Halfedge_around_facet_circulator
                                he_it = selected_fh->facet_begin(),
                                around_end = he_it;

                        Polyhedron::Vertex_handle v = he_it->vertex(), nearest_v = v;

                        Kernel::FT sq_dist = CGAL::squared_distance(*closest_point,
                                                                    v->point());
                        while(++he_it != around_end) {
                            v = he_it->vertex();
                            Kernel::FT new_sq_dist = CGAL::squared_distance(*closest_point,
                                                                            v->point());
                            if(new_sq_dist < sq_dist) {
                                sq_dist = new_sq_dist;
                                nearest_v = v;
                            }
                        }
                        //bottleneck
                        vertex_to_emit = (void*)(&*nearest_v);
                    }

                    if(QObject::receivers(SIGNAL(selected_edge(void*))) > 0
                            || QObject::receivers(SIGNAL(selected_halfedge(void*))) > 0)
                    {
                        Polyhedron::Halfedge_around_facet_circulator
                                he_it = selected_fh->facet_begin(),
                                around_end = he_it;

                        Polyhedron::Halfedge_handle nearest_h = he_it;
                        Kernel::FT sq_dist =
                                CGAL::squared_distance(*closest_point,
                                                       Kernel::Segment_3(he_it->vertex()->point(),
                                                                         he_it->opposite()->
                                                                         vertex()->
                                                                         point()));

                        while(++he_it != around_end)
                        {
                            Kernel::FT new_sq_dist =
                                    CGAL::squared_distance(*closest_point,
                                                           Kernel::Segment_3(he_it->vertex()->point(),
                                                                             he_it->opposite()->
                                                                             vertex()->
                                                                             point()));
                            if(new_sq_dist < sq_dist) {
                                sq_dist = new_sq_dist;
                                nearest_h = he_it;
                            }
                        }

                        Q_EMIT selected_halfedge((void*)(&*nearest_h));
                        Q_EMIT selected_edge((void*)(std::min)(&*nearest_h, &*nearest_h->opposite()));
                    }
                    Q_EMIT selected_vertex(vertex_to_emit);
                    Q_EMIT selected_facet((void*)(&*selected_fh));
                    if(d->erase_next_picked_facet_m) {
                        polyhedron()->erase_facet(selected_fh->halfedge());
                        polyhedron()->normalize_border();
                        //set_erase_next_picked_facet(false);
                        invalidateOpenGLBuffers();

                        Q_EMIT itemChanged();
                    }
                }
            }
        }
    }
    Base::select(orig_x, orig_y, orig_z, dir_x, dir_y, dir_z);
    Q_EMIT selection_done();
}

void Scene_polyhedron_item::update_vertex_indices()
{
    std::size_t id=0;
    for (Polyhedron::Vertex_iterator vit = polyhedron()->vertices_begin(),
         vit_end = polyhedron()->vertices_end(); vit != vit_end; ++vit)
    {
        vit->id()=id++;
    }
}
void Scene_polyhedron_item::update_facet_indices()
{
    std::size_t id=0;
    for (Polyhedron::Facet_iterator  fit = polyhedron()->facets_begin(),
         fit_end = polyhedron()->facets_end(); fit != fit_end; ++fit)
    {
        fit->id()=id++;
    }
}
void Scene_polyhedron_item::update_halfedge_indices()
{
    std::size_t id=0;
    for (Polyhedron::Halfedge_iterator hit = polyhedron()->halfedges_begin(),
         hit_end = polyhedron()->halfedges_end(); hit != hit_end; ++hit)
    {
        hit->id()=id++;
    }
}
void Scene_polyhedron_item::invalidate_aabb_tree()
{
  delete_aabb_tree(this);
}
QString Scene_polyhedron_item::computeStats(int type)
{
  double minl, maxl, meanl, midl;
  switch (type)
  {
  case MIN_LENGTH:
  case MAX_LENGTH:
  case MID_LENGTH:
  case MEAN_LENGTH:
  case NB_NULL_LENGTH:
    d->poly->normalize_border();
    edges_length(d->poly, minl, maxl, meanl, midl, d->number_of_null_length_edges);
  }

  double mini, maxi, ave;
  switch (type)
  {
  case MIN_ANGLE:
  case MAX_ANGLE:
  case MEAN_ANGLE:
    angles(d->poly, mini, maxi, ave);
  }
  double min_area, max_area, med_area, mean_area;
  switch (type)
  {
  case MIN_AREA:
  case MAX_AREA:
  case MEAN_AREA:
  case MED_AREA:
    if(!d->poly->is_pure_triangle())
    {
      return QString("n/a");
    }
    faces_area(d->poly, min_area, max_area, mean_area, med_area);
  }
  double min_altitude, min_ar, max_ar, mean_ar;
  switch (type)
  {
  case MIN_ALTITUDE:
  case MIN_ASPECT_RATIO:
  case MAX_ASPECT_RATIO:
  case MEAN_ASPECT_RATIO:
    if(!d->poly->is_pure_triangle())
    {
      return QString("n/a");
    }
    faces_aspect_ratio(d->poly, min_altitude, min_ar, max_ar, mean_ar);
  }

  switch(type)
  {
  case NB_VERTICES:
    return QString::number(d->poly->size_of_vertices());

  case NB_FACETS:
    return QString::number(d->poly->size_of_facets());

  case NB_CONNECTED_COMPOS:
  {
    typedef boost::graph_traits<Polyhedron>::face_descriptor face_descriptor;
    int i = 0;
    BOOST_FOREACH(face_descriptor f, faces(*(d->poly))){
      f->id() = i++;
    }
    boost::vector_property_map<int,
      boost::property_map<Polyhedron, boost::face_index_t>::type>
      fccmap(get(boost::face_index, *(d->poly)));
    return QString::number(PMP::connected_components(*(d->poly), fccmap));
  }
  case NB_BORDER_EDGES:
    d->poly->normalize_border();
    return QString::number(d->poly->size_of_border_halfedges());

  case NB_EDGES:
    return QString::number(d->poly->size_of_halfedges() / 2);

  case NB_DEGENERATED_FACES:
  {
    if (d->poly->is_pure_triangle())
    {
      if (d->number_of_degenerated_faces == (unsigned int)(-1))
        d->number_of_degenerated_faces = nb_degenerate_faces(d->poly, get(CGAL::vertex_point, *(d->poly)));
      return QString::number(d->number_of_degenerated_faces);
    }
    else
      return QString("n/a");
  }
  case AREA:
  {
    if (d->poly->is_pure_triangle())
    {
      if(d->area == -std::numeric_limits<double>::infinity())
        d->area = CGAL::Polygon_mesh_processing::area(*(d->poly));
      return QString::number(d->area);
    }
    else
      return QString("n/a");
  }
  case VOLUME:
  {
    if (d->poly->is_pure_triangle() && d->poly->is_closed())
    {
      if (d->volume == -std::numeric_limits<double>::infinity())
        d->volume = CGAL::Polygon_mesh_processing::volume(*(d->poly));
      return QString::number(d->volume);
    }
    else
      return QString("n/a");
  }
  case SELFINTER:
  {
    //todo : add a test about cache validity
    if (d->poly->is_pure_triangle())
      d->self_intersect = CGAL::Polygon_mesh_processing::does_self_intersect(*(d->poly));
    if (d->self_intersect)
      return QString("Yes");
    else if (d->poly->is_pure_triangle())
      return QString("No");
    else
      return QString("n/a");
  }
  case GENUS:
  {
    if(!d->poly->is_closed())
    {
      return QString("n/a");
    }
    else if(d->genus == -1)
    {
      std::ptrdiff_t s(d->poly->size_of_vertices()),
          a(d->poly->size_of_halfedges()/2),
          f(d->poly->size_of_facets());
      d->genus = 1.0 - double(s-a+f)/2.0;
    }
    if(d->genus < 0)
    {
      return QString("n/a");
    }
    else
    {
      return QString::number(d->genus);
    }

  }
  case MIN_LENGTH:
    return QString::number(minl);
  case MAX_LENGTH:
    return QString::number(maxl);
  case MID_LENGTH:
    return QString::number(midl);
  case MEAN_LENGTH:
    return QString::number(meanl);
  case NB_NULL_LENGTH:
    return QString::number(d->number_of_null_length_edges);

  case MIN_ANGLE:
    return QString::number(mini);
  case MAX_ANGLE:
    return QString::number(maxi);
  case MEAN_ANGLE:
    return QString::number(ave);
  case HOLES:
    return QString::number(nb_holes(d->poly));

  case MIN_AREA:
    return QString::number(min_area);
  case MAX_AREA:
    return QString::number(max_area);
  case MED_AREA:
    return QString::number(med_area);
  case MEAN_AREA:
    return QString::number(mean_area);
  case MIN_ALTITUDE:
    return QString::number(min_altitude);
  case MIN_ASPECT_RATIO:
    return QString::number(min_ar);
  case MAX_ASPECT_RATIO:
    return QString::number(max_ar);
  case MEAN_ASPECT_RATIO:
    return QString::number(mean_ar);
  case IS_PURE_TRIANGLE:
    if(d->poly->is_pure_triangle())
      return QString("yes");
    else
      return QString("no");
  case IS_PURE_QUAD:
    if (d->poly->is_pure_quad())
      return QString("yes");
    else
      return QString("no");
  }
  return QString();
}

CGAL::Three::Scene_item::Header_data Scene_polyhedron_item::header() const
{
  CGAL::Three::Scene_item::Header_data data;
  //categories

  data.categories.append(std::pair<QString,int>(QString("Properties"),9));
  data.categories.append(std::pair<QString,int>(QString("Faces"),10));
  data.categories.append(std::pair<QString,int>(QString("Edges"),7));
  data.categories.append(std::pair<QString,int>(QString("Angles"),2));


  //titles
  data.titles.append(QString("#Vertices"));
  data.titles.append(QString("#Connected Components"));
  data.titles.append(QString("#Border Edges"));
  data.titles.append(QString("Pure Triangle"));
  data.titles.append(QString("Pure Quad"));
  data.titles.append(QString("#Degenerated Faces"));
  data.titles.append(QString("Connected Components of the Boundary"));
  data.titles.append(QString("Area"));
  data.titles.append(QString("Volume"));
  data.titles.append(QString("Self-Intersecting"));
  data.titles.append(QString("#Faces"));
  data.titles.append(QString("Min Area"));
  data.titles.append(QString("Max Area"));
  data.titles.append(QString("Median Area"));
  data.titles.append(QString("Mean Area"));
  data.titles.append(QString("Min Altitude"));
  data.titles.append(QString("Min Aspect-Ratio"));
  data.titles.append(QString("Max Aspect-Ratio"));
  data.titles.append(QString("Mean Aspect-Ratio"));
  data.titles.append(QString("Genus"));
  data.titles.append(QString("#Edges"));
  data.titles.append(QString("Minimum Length"));
  data.titles.append(QString("Maximum Length"));
  data.titles.append(QString("Median Length"));
  data.titles.append(QString("Mean Length"));
  data.titles.append(QString("#Null Length"));
  data.titles.append(QString("Minimum"));
  data.titles.append(QString("Maximum"));
  data.titles.append(QString("Average"));
  return data;
}

void Scene_polyhedron_item::printPrimitiveId(QPoint point, CGAL::Three::Viewer_interface *viewer)
{
  typedef Input_facets_AABB_tree Tree;
  Tree* aabb_tree = static_cast<Input_facets_AABB_tree*>(d->get_aabb_tree());
  if(!aabb_tree)
    return;
  Polyhedron::Facet_handle selected_fh;
  Kernel::Point_3 pt_under;
  const CGAL::qglviewer::Vec offset = static_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first())->offset();
  if(find_primitive_id(point, aabb_tree, viewer, selected_fh, pt_under))
    d->fillTargetedIds(selected_fh, pt_under, viewer, offset);

}
void Scene_polyhedron_item_priv::fillTargetedIds(const Polyhedron::Facet_handle& selected_fh,
                                                 const Kernel::Point_3& pt_under,
                                                 CGAL::Three::Viewer_interface *viewer,
                                                 const CGAL::qglviewer::Vec& offset)
{
  compute_displayed_ids(*poly,
                        viewer,
                        selected_fh,
                        pt_under,
                        offset,
                        textVItems,
                        textEItems,
                        textFItems,
                        &targeted_id);


  if(vertices_displayed
     && !textVItems->isEmpty())
    item->showVertices(true);
  if(edges_displayed
    && !textEItems->isEmpty())
    item->showEdges(true);
  if(faces_displayed
     && !textFItems->isEmpty())
    item->showFaces(true);

}

bool Scene_polyhedron_item::printVertexIds(CGAL::Three::Viewer_interface *viewer) const
{
  if(d->vertices_displayed)
  {
    return ::printVertexIds(*d->poly,
                            d->textVItems,
                            viewer);
  }
  return true;
}

bool Scene_polyhedron_item::printEdgeIds(CGAL::Three::Viewer_interface *viewer) const
{
  if(d->edges_displayed)
  {
    return ::printEdgeIds(*d->poly,
                            d->textEItems,
                            viewer);
  }
  return true;
}

bool Scene_polyhedron_item::printFaceIds(CGAL::Three::Viewer_interface *viewer) const
{
  if(d->faces_displayed)
  {
    return ::printFaceIds(*d->poly,
                            d->textFItems,
                            viewer);
  }
  return true;
}

void Scene_polyhedron_item_priv::killIds()
{
  CGAL::Three::Viewer_interface* viewer =
      qobject_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first());
  deleteIds(viewer,
            textVItems,
            textEItems,
            textFItems,
            &targeted_id);
}

void Scene_polyhedron_item::printAllIds(CGAL::Three::Viewer_interface *viewer)
{
  static bool all_ids_displayed = false;

  all_ids_displayed = !all_ids_displayed;
  if(all_ids_displayed )
  {
    bool s1(printVertexIds(viewer)),
        s2(printEdgeIds(viewer)),
        s3(printFaceIds(viewer));
    if((s1 && s2 && s3))
    {
      viewer->update();
    }
    return;
  }
  d->killIds();
}

bool Scene_polyhedron_item::testDisplayId(double x, double y, double z, CGAL::Three::Viewer_interface* viewer)const
{
  const CGAL::qglviewer::Vec offset = static_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first())->offset();
  Kernel::Point_3 src(x - offset.x,
                      y - offset.y,
                      z - offset.z);
  Kernel::Point_3 dest(viewer->camera()->position().x - offset.x,
                       viewer->camera()->position().y - offset.y,
                       viewer->camera()->position().z - offset.z);
  Kernel::Vector_3 v(src,dest);
  v = 0.01*v;
  Kernel::Point_3 point = src;
  point = point + v;
  Kernel::Segment_3 query(point, dest);
  return !static_cast<Input_facets_AABB_tree*>(d->get_aabb_tree())->do_intersect(query);
}


std::vector<QColor>& Scene_polyhedron_item::color_vector() {return d->colors_;}
void Scene_polyhedron_item::set_color_vector_read_only(bool on_off) {d->plugin_has_set_color_vector_m=on_off;}
bool Scene_polyhedron_item::is_color_vector_read_only() { return d->plugin_has_set_color_vector_m;}
int Scene_polyhedron_item::getNumberOfNullLengthEdges(){return d->number_of_null_length_edges;}
int Scene_polyhedron_item::getNumberOfDegeneratedFaces(){return d->number_of_degenerated_faces;}
bool Scene_polyhedron_item::triangulated(){return d->poly->is_pure_triangle();}
bool Scene_polyhedron_item::self_intersected(){return !(d->self_intersect);}
void Scene_polyhedron_item::setItemIsMulticolor(bool b){ 
  d->is_multicolor = b; 
  this->setProperty("NbPatchIds", 0);//for the joinandsplit_plugin
}
bool Scene_polyhedron_item::isItemMulticolor(){ return d->is_multicolor;}
bool Scene_polyhedron_item::intersect_face(double orig_x,
                                           double orig_y,
                                           double orig_z,
                                           double dir_x,
                                           double dir_y,
                                           double dir_z,
                                           Polyhedron::Facet_handle f)
{
  typedef Input_facets_AABB_tree Tree;
  typedef Tree::Object_and_primitive_id Object_and_primitive_id;

  Tree* aabb_tree = static_cast<Tree*>(d->get_aabb_tree());
  if(aabb_tree)
  {
    const Kernel::Point_3 ray_origin(orig_x, orig_y, orig_z);
    const Kernel::Vector_3 ray_dir(dir_x, dir_y, dir_z);
    const Kernel::Ray_3 ray(ray_origin, ray_dir);
    typedef std::list<Object_and_primitive_id> Intersections;
    Intersections intersections;
    aabb_tree->all_intersections(ray, std::back_inserter(intersections));
    Intersections::iterator closest = intersections.begin();
    if(closest != intersections.end())
    {
      const Kernel::Point_3* closest_point =
          CGAL::object_cast<Kernel::Point_3>(&closest->first);
      for(Intersections::iterator
          it = boost::next(intersections.begin()),
          end = intersections.end();
          it != end; ++it)
      {
        if(! closest_point) {
          closest = it;
        }
        else {
          const Kernel::Point_3* it_point =
              CGAL::object_cast<Kernel::Point_3>(&it->first);
          if(it_point &&
             (ray_dir * (*it_point - *closest_point)) < 0)
          {
            closest = it;
            closest_point = it_point;
          }
        }
      }
      if(closest_point)
      {
        Polyhedron::Facet_handle intersected_face = closest->second;
        return intersected_face == f;
      }
    }
  }
  return false;

}

bool Scene_polyhedron_item::supportsRenderingMode(RenderingMode m) const
{
  return (
        m!=PointsPlusNormals &&
      m!=ShadedPoints &&
      !(m==Flat && d->no_flat)
      );
}

void Scene_polyhedron_item::set_flat_disabled(bool b)
{
  d->no_flat = b;
  invalidateOpenGLBuffers();
  itemChanged();
}

void Scene_polyhedron_item::itemAboutToBeDestroyed(Scene_item *item)
{
  Scene_item::itemAboutToBeDestroyed(item);
  if(d && item == this)
  {
    delete d;
    d=NULL;
  }
}

void Scene_polyhedron_item::zoomToPosition(const QPoint &point, CGAL::Three::Viewer_interface *viewer) const
{
  typedef Input_facets_AABB_tree Tree;
  typedef Tree::Intersection_and_primitive_id<Kernel::Ray_3>::Type Intersection_and_primitive_id;

  Tree* aabb_tree = static_cast<Input_facets_AABB_tree*>(d->get_aabb_tree());
  if(aabb_tree) {

    const CGAL::qglviewer::Vec offset =
        static_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first())->offset();
    //find clicked facet
    bool found = false;
    const Kernel::Point_3 ray_origin(viewer->camera()->position().x - offset.x,
                                     viewer->camera()->position().y - offset.y,
                                     viewer->camera()->position().z - offset.z);
    CGAL::qglviewer::Vec point_under = viewer->camera()->pointUnderPixel(point,found);
    CGAL::qglviewer::Vec dir = point_under - viewer->camera()->position();
    const Kernel::Vector_3 ray_dir(dir.x, dir.y, dir.z);
    const Kernel::Ray_3 ray(ray_origin, ray_dir);
    typedef std::list<Intersection_and_primitive_id> Intersections;
    Intersections intersections;
    aabb_tree->all_intersections(ray, std::back_inserter(intersections));

    if(!intersections.empty()) {
      Intersections::iterator closest = intersections.begin();
      const Kernel::Point_3* closest_point =
          boost::get<Kernel::Point_3>(&closest->first);
      for(Intersections::iterator
          it = boost::next(intersections.begin()),
          end = intersections.end();
          it != end; ++it)
      {
        if(! closest_point) {
          closest = it;
        }
        else {
          const Kernel::Point_3* it_point =
              boost::get<Kernel::Point_3>(&it->first);
          if(it_point &&
             (ray_dir * (*it_point - *closest_point)) < 0)
          {
            closest = it;
            closest_point = it_point;
          }
        }
      }
      if(closest_point) {
        Polyhedron::Facet_handle selected_fh = closest->second;
        //compute new position and orientation
        Kernel::Vector_3 face_normal = CGAL::Polygon_mesh_processing::
            compute_face_normal(selected_fh,
                                *d->poly,
                                CGAL::Polygon_mesh_processing::parameters::all_default());


        double x(0), y(0), z(0),
            xmin(std::numeric_limits<double>::infinity()), ymin(std::numeric_limits<double>::infinity()), zmin(std::numeric_limits<double>::infinity()),
            xmax(-std::numeric_limits<double>::infinity()), ymax(-std::numeric_limits<double>::infinity()), zmax(-std::numeric_limits<double>::infinity());
        int total(0);
        BOOST_FOREACH(Polyhedron::Vertex_handle vh, vertices_around_face(selected_fh->halfedge(), *d->poly))
        {
          x+=vh->point().x();
          y+=vh->point().y();
          z+=vh->point().z();

          if(vh->point().x() < xmin)
            xmin = vh->point().x();
          if(vh->point().y() < ymin)
            ymin = vh->point().y();
          if(vh->point().z() < zmin)
            zmin = vh->point().z();

          if(vh->point().x() > xmax)
            xmax = vh->point().x();
          if(vh->point().y() > ymax)
            ymax = vh->point().y();
          if(vh->point().z() > zmax)
            zmax = vh->point().z();

          ++total;
        }
        Kernel::Point_3 centroid(x/total + offset.x,
                                 y/total + offset.y,
                                 z/total + offset.z);

        CGAL::qglviewer::Quaternion new_orientation(CGAL::qglviewer::Vec(0,0,-1),
                                              CGAL::qglviewer::Vec(-face_normal.x(), -face_normal.y(), -face_normal.z()));
        double max_side = (std::max)((std::max)(xmax-xmin, ymax-ymin),
                                     zmax-zmin);
        //put the camera in way we are sure the longest side is entirely visible on the screen
        //See openGL's frustum definition
        double factor = CGAL::abs(max_side/(tan(viewer->camera()->aspectRatio()/
                                        (viewer->camera()->fieldOfView()/2))));

        Kernel::Point_3 new_pos = centroid + factor*face_normal ;
        viewer->camera()->setSceneCenter(CGAL::qglviewer::Vec(centroid.x(),
                                                        centroid.y(),
                                                        centroid.z()));
        viewer->moveCameraToCoordinates(QString("%1 %2 %3 %4 %5 %6 %7").arg(new_pos.x())
                                                                       .arg(new_pos.y())
                                                                       .arg(new_pos.z())
                                                                       .arg(new_orientation[0])
                                                                       .arg(new_orientation[1])
                                                                       .arg(new_orientation[2])
                                                                       .arg(new_orientation[3]));
      }
    }
  }

}

void Scene_polyhedron_item::resetColors()
{
  setItemIsMulticolor(false);
  invalidateOpenGLBuffers();
  itemChanged();
}

void Scene_polyhedron_item::showVertices(bool b)
{
  CGAL::Three::Viewer_interface* viewer =
      qobject_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first());
  TextRenderer *renderer = viewer->textRenderer();
  if(b)
    if(d->textVItems->isEmpty())
    {
      d->vertices_displayed = b;
      printVertexIds(viewer);
    }
    else
      renderer->addTextList(d->textVItems);
  else
    renderer->removeTextList(d->textVItems);
  viewer->update();
  d->vertices_displayed = b;
}

void Scene_polyhedron_item::showEdges(bool b)
{
  CGAL::Three::Viewer_interface* viewer =
      qobject_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first());
  TextRenderer *renderer = viewer->textRenderer();
  if(b)
    if(d->textEItems->isEmpty())
    {
      d->edges_displayed = b;
      printEdgeIds(viewer);
    }
    else
      renderer->addTextList(d->textEItems);
  else
    renderer->removeTextList(d->textEItems);
  viewer->update();
  d->edges_displayed = b;
}

void Scene_polyhedron_item::showFaces(bool b)
{
  CGAL::Three::Viewer_interface* viewer =
      qobject_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first());
  TextRenderer *renderer = viewer->textRenderer();
  if(b)
  {
    if(d->textFItems->isEmpty())
    {
      d->faces_displayed = b;
      printFaceIds(viewer);
    }
    else
      renderer->addTextList(d->textFItems);
  }
  else
    renderer->removeTextList(d->textFItems);
  viewer->update();
  d->faces_displayed = b;
}

void Scene_polyhedron_item::showPrimitives(bool)
{
  CGAL::Three::Viewer_interface* viewer =
      qobject_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first());
  printAllIds(viewer);
}
void Scene_polyhedron_item::zoomToId()
{
  Polyhedron::Facet_handle selected_fh;
  bool ok;
  QString text = QInputDialog::getText(QApplication::activeWindow(), tr("Zoom to Index"),
                                       tr("Simplex"), QLineEdit::Normal,
                                       tr("v0"), &ok);
  if(!ok)
    return;

  CGAL::Three::Viewer_interface* viewer =
      qobject_cast<CGAL::Three::Viewer_interface*>(CGAL::QGLViewer::QGLViewerPool().first());
  Point p;
  QString id = text.right(text.length()-1);
  int return_value = ::zoomToId(*d->poly, text, viewer, selected_fh, p);
  switch(return_value)
  {
  case 1:
    QMessageBox::warning(QApplication::activeWindow(),
                       "ERROR",
                       tr("Input must be of the form [v/e/f][int]")
                       );
    return;
  case 2:
    QMessageBox::warning(QApplication::activeWindow(),
                       "ERROR",
                       tr("No vertex with id %1").arg(id)
                       );
    return;
  case 3:
    QMessageBox::warning(QApplication::activeWindow(),
                       "ERROR",
                       tr("No edge with id %1").arg(id)
                       );
    return;
  case 4:
    QMessageBox::warning(QApplication::activeWindow(),
                       "ERROR",
                       tr("No face with id %1").arg(id)
                       );
    return;
  default: //case 0
    d->fillTargetedIds(selected_fh, p, viewer, viewer->offset());
    break;
  }
}
bool Scene_polyhedron_item::shouldDisplayIds(CGAL::Three::Scene_item *current_item) const
{
  return this == current_item;
}
