diff --git a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
index 34bd3e6d67b..c25db11a964 100644
--- a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
@@ -1324,7 +1324,5 @@ Scene_c3t3_item::setColor(QColor c)
   color_ = c;
   compute_color_map(c);
   invalidateOpenGLBuffers();
-// changed() doesn't work because the timerEvent delays it out of the draw
-// function and the intersection is not drawn before the next draw call
   are_intersection_buffers_filled = false;
 }
diff --git a/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.cpp b/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.cpp
index a17717df8f8..d48e021121f 100644
--- a/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.cpp
@@ -353,7 +353,6 @@ Scene_implicit_function_item(Implicit_function_interface* f)
     texture = new Texture(grid_size_-1,grid_size_-1);
     blue_color_ramp_.build_blue();
     red_color_ramp_.build_red();
-    startTimer(0);
     //Generates an integer which will be used as ID for each buffer
     compute_min_max();
     compute_function_grid();
@@ -583,7 +582,7 @@ Scene_implicit_function_item::invalidateOpenGLBuffers()
 }
 
 
-void Scene_implicit_function_item::timerEvent(QTimerEvent* /*event*/)
+void Scene_implicit_function_item::updateCutPlane()
 { // just handle deformation - paint like selection is handled in eventFilter()
   if(need_update_) {
     compute_function_grid();
diff --git a/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.h b/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.h
index 053f2d566ce..ba163a5cbf1 100644
--- a/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.h
+++ b/Polyhedron/demo/Polyhedron/Scene_implicit_function_item.h
@@ -71,9 +71,9 @@ public:
   virtual QString toolTip() const;
   virtual void invalidateOpenGLBuffers();
 public Q_SLOTS:
-  void plane_was_moved() { need_update_ = true; }
+  void plane_was_moved() { need_update_ = true; QTimer::singleShot(0, this, SLOT(updateCutPlane())); }
   void compute_function_grid() const;
-  void timerEvent(QTimerEvent*);
+  void updateCutPlane();
 
 private:
   typedef qglviewer::Vec                  Point;