diff --git a/Linear_cell_complex/demo/Linear_cell_complex/MainWindow.ui b/Linear_cell_complex/demo/Linear_cell_complex/MainWindow.ui
index d63b9d7c9b1..6a9f06c68d2 100644
--- a/Linear_cell_complex/demo/Linear_cell_complex/MainWindow.ui
+++ b/Linear_cell_complex/demo/Linear_cell_complex/MainWindow.ui
@@ -38,7 +38,7 @@
    </property>
    <widget class="QMenu" name="menuFile">
     <property name="title">
-     <string>&amp;File</string>
+     <string>File</string>
     </property>
     <addaction name="actionLoad"/>
     <addaction name="actionSave"/>
@@ -55,7 +55,7 @@
    </widget>
    <widget class="QMenu" name="menuOperations">
     <property name="title">
-     <string>&amp;Operations</string>
+     <string>Operations</string>
     </property>
     <addaction name="actionInsert_center_vertices"/>
     <addaction name="actionTriangulate_all_facets"/>
@@ -75,7 +75,7 @@
    </widget>
    <widget class="QMenu" name="menuCreations">
     <property name="title">
-     <string>&amp;Creations</string>
+     <string>Creations</string>
     </property>
     <addaction name="actionCreate_cube"/>
     <addaction name="actionCreate3Cubes"/>
@@ -88,7 +88,7 @@
    </widget>
    <widget class="QMenu" name="menuView">
     <property name="title">
-     <string>&amp;View</string>
+     <string>View</string>
     </property>
     <addaction name="separator"/>
     <addaction name="actionExtend_filled_volumes"/>
@@ -103,67 +103,67 @@
   <widget class="QStatusBar" name="statusbar"/>
   <action name="actionImportOFF">
    <property name="text">
-    <string>&amp;Import OFF</string>
+    <string>Import OFF</string>
    </property>
   </action>
   <action name="actionQuit">
    <property name="text">
-    <string>&amp;Quit</string>
+    <string>Quit</string>
    </property>
   </action>
   <action name="actionSubdivide">
    <property name="text">
-    <string>&amp;Subdivide all volumes</string>
+    <string>Subdivide all volumes</string>
    </property>
   </action>
   <action name="actionSubdivide_pqq">
    <property name="text">
-    <string>&amp;Subdivide all volumes - by Pqq</string>
+    <string>Subdivide all volumes - by Pqq</string>
    </property>
   </action>
   <action name="actionCreate3Cubes">
    <property name="text">
-    <string>Create &amp;3 cubes</string>
+    <string>Create 3 cubes</string>
    </property>
   </action>
   <action name="actionImport3DTDS">
    <property name="text">
-    <string>Import 3D&amp;TS</string>
+    <string>Import 3DTS</string>
    </property>
   </action>
   <action name="actionClear">
    <property name="text">
-    <string>&amp;Clear</string>
+    <string>Clear</string>
    </property>
   </action>
   <action name="actionCreate2Volumes">
    <property name="text">
-    <string>Create &amp;2 volumes</string>
+    <string>Create 2 volumes</string>
    </property>
   </action>
   <action name="actionDual_3">
    <property name="text">
-    <string>&amp;Dual</string>
+    <string>Dual</string>
    </property>
   </action>
   <action name="actionClose_volume">
    <property name="text">
-    <string>&amp;Close all volumes</string>
+    <string>Close all volumes</string>
    </property>
   </action>
   <action name="actionCreate_cube">
    <property name="text">
-    <string>Create &amp;cube</string>
+    <string>Create cube</string>
    </property>
   </action>
   <action name="actionSew3_same_facets">
    <property name="text">
-    <string>S&amp;ew3 all same facets</string>
+    <string>Sew3 all same facets</string>
    </property>
   </action>
   <action name="actionCreate_mesh">
    <property name="text">
-    <string>Create &amp;mesh</string>
+    <string>Create mesh</string>
    </property>
   </action>
   <action name="actionCreate_Menger_Sponge">
@@ -173,22 +173,22 @@
   </action>
   <action name="actionRemove_filled_volumes">
    <property name="text">
-    <string>&amp;Remove volumes</string>
+    <string>Remove volumes</string>
    </property>
   </action>
   <action name="actionTriangulate_all_facets">
    <property name="text">
-    <string>&amp;Triangulate facets</string>
+    <string>Triangulate facets</string>
    </property>
   </action>
   <action name="actionUnsew3_all">
    <property name="text">
-    <string>&amp;Unsew3 volumes</string>
+    <string>Unsew3 volumes</string>
    </property>
   </action>
   <action name="actionInsideOut">
    <property name="text">
-    <string>Reverse &amp;orientation</string>
+    <string>Reverse orientation</string>
    </property>
   </action>
   <action name="actionVolume_list">
@@ -201,12 +201,12 @@
   </action>
   <action name="actionExtend_filled_volumes">
    <property name="text">
-    <string>Extend &amp;filled volumes</string>
+    <string>Extend filled volumes</string>
    </property>
   </action>
   <action name="actionExtend_hidden_volumes">
    <property name="text">
-    <string>Extend &amp;hidden volumes</string>
+    <string>Extend hidden volumes</string>
    </property>
   </action>
   <action name="actionCompute_Voronoi_3D">
@@ -216,7 +216,7 @@
   </action>
   <action name="actionMerge_all_volumes">
    <property name="text">
-    <string>&amp;Merge volumes</string>
+    <string>Merge volumes</string>
    </property>
   </action>
   <action name="actionCreate_Sierpinski_Carpet">
@@ -231,12 +231,12 @@
   </action>
   <action name="actionLoad">
    <property name="text">
-    <string>&amp;Load</string>
+    <string>Load</string>
    </property>
   </action>
   <action name="actionSave">
    <property name="text">
-    <string>&amp;Save</string>
+    <string>Save</string>
    </property>
   </action>
   <action name="actionImportMoka">
diff --git a/Linear_cell_complex/demo/Linear_cell_complex/Viewer.cpp b/Linear_cell_complex/demo/Linear_cell_complex/Viewer.cpp
index a773ebdb3f1..6a7ba68de51 100644
--- a/Linear_cell_complex/demo/Linear_cell_complex/Viewer.cpp
+++ b/Linear_cell_complex/demo/Linear_cell_complex/Viewer.cpp
@@ -19,17 +19,32 @@ Viewer::Viewer(QWidget *parent)
   : Base(parent, m_graphic_buffer, ""),
     m_previous_scene_empty(true)
 {
-  m_drawing_functor.volume_color=[](const LCC & alcc,
-                                    Dart_const_handle dh)->CGAL::IO::Color
-  { return alcc.template info<3>(dh).color(); };
+  m_drawing_functor.face_color=[](const LCC & alcc,
+                                    Dart_const_descriptor dh)->CGAL::IO::Color
+  {
+    if(alcc.template is_free<3>(dh))
+    { return alcc.template info<3>(dh).color(); }
 
-  m_drawing_functor.colored_volume=[](const LCC &, Dart_const_handle)->bool
+    if(!alcc.template info<3>(dh).is_visible() ||
+       !alcc.template info<3>(dh).is_filled())
+    { return alcc.template info<3>(alcc.template beta<3>(dh)).color(); }
+
+    if(!alcc.template info<3>(alcc.template beta<3>(dh)).is_visible() ||
+       !alcc.template info<3>(alcc.template beta<3>(dh)).is_filled())
+    { return alcc.template info<3>(dh).color(); }
+
+    const CGAL::IO::Color& c1=alcc.template info<3>(dh).color();
+    const CGAL::IO::Color& c2=alcc.template info<3>(alcc.template beta<3>(dh)).color();
+    return CGAL::IO::Color((c1[0]+c2[0])/2, (c1[1]+c2[1])/2, (c1[2]+c2[2])/2);
+  };
+
+  m_drawing_functor.colored_face=[](const LCC &, Dart_const_descriptor)->bool
   { return true; };
 
-  m_drawing_functor.draw_volume=[](const LCC & alcc, Dart_const_handle dh)->bool
+  m_drawing_functor.draw_volume=[](const LCC & alcc, Dart_const_descriptor dh)->bool
   { return alcc.template info<3>(dh).is_visible(); };
 
-  m_drawing_functor.volume_wireframe=[](const LCC& alcc, Dart_const_handle dh)->bool
+  m_drawing_functor.volume_wireframe=[](const LCC& alcc, Dart_const_descriptor dh)->bool
   { return !(alcc.template info<3>(dh).is_filled()); };
 }
 
@@ -69,4 +84,5 @@ void Viewer::keyPressEvent(QKeyEvent *e)
   Base::keyPressEvent(e);
 }
 
-QString Viewer::helpString() const { return Base::helpString("LCC Demo"); }
+QString Viewer::helpString() const
+{ return Base::helpString("LCC Demo"); }
diff --git a/Linear_cell_complex/demo/Linear_cell_complex/Viewer.h b/Linear_cell_complex/demo/Linear_cell_complex/Viewer.h
index 3b782fe09a8..c72feee6f32 100644
--- a/Linear_cell_complex/demo/Linear_cell_complex/Viewer.h
+++ b/Linear_cell_complex/demo/Linear_cell_complex/Viewer.h
@@ -35,10 +35,10 @@ public Q_SLOTS:
 
 private:
   CGAL::Drawing_functor_with_volume<LCC,
-                                         Dart_const_handle,
-                                         Dart_const_handle,
-                                         Dart_const_handle,
-                                         Dart_const_handle> m_drawing_functor;
+                                         Dart_const_descriptor,
+                                         Dart_const_descriptor,
+                                         Dart_const_descriptor,
+                                         Dart_const_descriptor> m_drawing_functor;
   CGAL::Graphic_buffer<float> m_graphic_buffer;
   Scene* scene;
   bool m_previous_scene_empty;
diff --git a/Linear_cell_complex/include/CGAL/draw_linear_cell_complex.h b/Linear_cell_complex/include/CGAL/draw_linear_cell_complex.h
index d3718681031..add255dfa6e 100644
--- a/Linear_cell_complex/include/CGAL/draw_linear_cell_complex.h
+++ b/Linear_cell_complex/include/CGAL/draw_linear_cell_complex.h
@@ -111,7 +111,7 @@ void compute_edge(typename LCC::Dart_const_handle dh, const LCC *lcc,
 
   const typename LCC::Point& p1=lcc->point(dh);
   typename LCC::Dart_const_handle d2=lcc->other_extremity(dh);
-  if (d2!=nullptr)
+  if (d2!=LCC::null_descriptor)
   {
     if (m_drawing_functor.colored_edge(*lcc, dh))
     {
@@ -173,7 +173,9 @@ void compute_elements(const LCC *lcc,
             lcc->is_marked(itv, oriented_mark) &&
             m_drawing_functor.draw_face(*lcc, itv))
         {
-          if (!m_drawing_functor.volume_wireframe(*lcc, itv) &&
+          if ((!m_drawing_functor.volume_wireframe(*lcc, itv) ||
+               (!lcc->template is_free<3>(itv) &&
+                !m_drawing_functor.volume_wireframe(*lcc, lcc->template beta<3>(itv)))) &&
               !m_drawing_functor.face_wireframe(*lcc, itv))
           { compute_face(itv, it, lcc, m_drawing_functor, graphic_buffer); }
           for(typename LCC::template Dart_of_cell_basic_range<2>::const_iterator
@@ -240,7 +242,8 @@ void add_in_graphic_buffer(const CGAL_LCC_TYPE &alcc,
                            CGAL::Graphic_buffer<BufferType> &graphic_buffer,
                            const DrawingFunctor &m_drawing_functor)
 {
-  draw_function_for_lcc::compute_elements(&alcc, graphic_buffer, m_drawing_functor);
+  draw_function_for_lcc::compute_elements(static_cast<const Refs*>(&alcc),
+                                          graphic_buffer, m_drawing_functor);
 }
 
 // add_in_graphic_buffer: to add a LCC in the given graphic buffer, without a