void Scene_polyhedron_shortest_path_item::initialize(Scene_polyhedron_item* polyhedronItem, Scene_interface* sceneInterface, Messages_interface* messages, QMainWindow* mainWindow)
{
  this->m_mainWindow = mainWindow;
  this->m_messages = messages;
  this->poly_item = polyhedronItem;
  this->m_sceneInterface = sceneInterface;
  connect(polyhedronItem, SIGNAL(item_is_about_to_be_changed()), this, SLOT(poly_item_changed())); 
  QGLViewer* viewer = *QGLViewer::QGLViewerPool().begin();
  viewer->installEventFilter(this);
  m_mainWindow->installEventFilter(this);
  recreate_shortest_path_object();
}
Scene_edit_polyhedron_item::Scene_edit_polyhedron_item
(Scene_polyhedron_item* poly_item,
 Ui::DeformMesh* ui_widget,
 QMainWindow* mw)
  : Scene_item(NumberOfBuffers,NumberOfVaos),
    ui_widget(ui_widget),
    poly_item(poly_item),
    is_rot_free(true),
    own_poly_item(true),
    k_ring_selector(poly_item, mw, Scene_polyhedron_item_k_ring_selection::Active_handle::VERTEX, true)
{
  nb_ROI = 0;
  nb_sphere = 0;
  nb_control = 0;
  nb_axis = 0;
  nb_bbox = 0;
  mw->installEventFilter(this);
  // bind vertex picking
  connect(&k_ring_selector, SIGNAL(selected(const std::set<Polyhedron::Vertex_handle>&)), this,
          SLOT(selected(const std::set<Polyhedron::Vertex_handle>&)));

  poly_item->set_color_vector_read_only(true); // to prevent recomputation of color vector in invalidateOpenGLBuffers()
  poly_item->update_vertex_indices();

  deform_mesh = new Deform_mesh(*(poly_item->polyhedron()),
                                Deform_mesh::Vertex_index_map(),
                                Deform_mesh::Hedge_index_map(),
                                Array_based_vertex_point_map(&positions));

  length_of_axis = bbox().diagonal_length() / 15.0;

  // interleave events of viewer (there is only one viewer) 
  QGLViewer* viewer = *QGLViewer::QGLViewerPool().begin();
  viewer->installEventFilter(this);
    
  // create an empty group of control vertices for starting
  create_ctrl_vertices_group();
   
  // start QObject's timer for continuous effects 
  // (deforming mesh while mouse not moving)
  startTimer(0);

  // Required for drawing functionality
  reset_drawing_data();

    //Generates an integer which will be used as ID for each buffer

    const char vertex_shader_source_bbox[] =
    {
        "#version 120 \n"
        "attribute highp vec3 vertex; \n"
        "attribute highp vec3 colors; \n"

        "uniform highp mat4 mvp_matrix; \n"
        "uniform highp mat4 rotations; \n"
        "uniform highp vec3 translation; \n"
        "uniform highp vec3 translation_2; \n"
        "varying highp vec3 fColors; \n"
        " \n"

        "void main(void) \n"
        "{ \n"
        "   fColors = colors; \n"
        "   gl_Position = mvp_matrix * (rotations *(vec4(translation_2,0.0)+vec4(vertex,1.0) )+ vec4(translation,0.0)) ; \n"
        "} \n"
    };
    const char fragment_shader_source[]=
    {
        "#version 120 \n"
        "varying vec3 fColors; \n"
        " \n"
        "void main(void) \n"
        "{ \n"
        " gl_FragColor = vec4(fColors, 1.0); \n"
        "} \n"
    };
    bbox_program.addShaderFromSourceCode(QOpenGLShader::Vertex,vertex_shader_source_bbox);
    bbox_program.addShaderFromSourceCode(QOpenGLShader::Fragment,fragment_shader_source);
    bbox_program.link();

    ui_widget->remeshing_iterations_spinbox->setValue(1);

    ui_widget->remeshing_edge_length_spinbox->setValue(length_of_axis);
    ui_widget->remeshing_edge_length_spinbox->setDisabled(true);
    ui_widget->remeshingEdgeLengthInput_checkBox->setChecked(false);
    connect(ui_widget->remeshingEdgeLengthInput_checkBox, SIGNAL(toggled(bool)),
            ui_widget->remeshing_edge_length_spinbox, SLOT(setEnabled(bool)));

    //the spheres :
    create_Sphere(length_of_axis/15.0);
    invalidateOpenGLBuffers();
}