diff --git a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Optimization_plugin_cgal_code.cpp b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Optimization_plugin_cgal_code.cpp
index ea98ff61bfd..3475f12e163 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Optimization_plugin_cgal_code.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/Optimization_plugin_cgal_code.cpp
@@ -133,6 +133,7 @@ Optimizer_thread* cgal_code_optimization(Scene_c3t3_item& c3t3_item,
   if ( NULL != sm_item )
   {
     const_cast<Scene_surface_mesh_item*>(sm_item)->setItemIsMulticolor(true);
+    const_cast<Scene_surface_mesh_item*>(sm_item)->computeItemColorVectorAutomatically(true);
     // Build domain
     const SMesh* smesh = sm_item->face_graph();
     if ( NULL == smesh )
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Partition_graph_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Partition_graph_plugin.cpp
index 8a252edf612..c2b390a14bd 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Partition_graph_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Partition_graph_plugin.cpp
@@ -97,8 +97,11 @@ private:
     QApplication::setOverrideCursor(Qt::WaitCursor);
     item->face_graph()->collect_garbage();
     item->color_vector().clear();
-    if(!item->hasPatchIds())
+    if(!item->hasPatchIds()){
       item->setItemIsMulticolor(true);
+      item->computeItemColorVectorAutomatically(true);
+    }
+    
     typedef boost::property_map<FaceGraph,CGAL::face_patch_id_t<int> >::type PatchIDMap;
     FaceGraph* fg =item->face_graph();
     boost::property_map<FaceGraph, boost::vertex_index_t>::type 
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Detect_sharp_edges_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PMP/Detect_sharp_edges_plugin.cpp
index f7f559c373c..357f34c8eca 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Detect_sharp_edges_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Detect_sharp_edges_plugin.cpp
@@ -133,6 +133,7 @@ void Polyhedron_demo_detect_sharp_edges_plugin::detectSharpEdges(bool input_dial
                                                .vertex_incident_patches_map(vip));
     //update item
     item->setItemIsMulticolor(true);
+    item->computeItemColorVectorAutomatically(true);
     item->invalidateOpenGLBuffers();
 
     // update scene
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Isotropic_remeshing_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PMP/Isotropic_remeshing_plugin.cpp
index 3fa8fcca4fe..60a0209510c 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Isotropic_remeshing_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Isotropic_remeshing_plugin.cpp
@@ -473,7 +473,16 @@ public Q_SLOTS:
         }
         selection_item->polyhedron_item()->setColor(
               selection_item->polyhedron_item()->color());
-        selection_item->polyhedron_item()->setItemIsMulticolor(fpmap_valid);
+        if(fpmap_valid)
+        {
+          selection_item->polyhedron_item()->setItemIsMulticolor(true);
+          selection_item->polyhedron_item()->computeItemColorVectorAutomatically(true);
+        }
+        else
+        {
+          selection_item->polyhedron_item()->setItemIsMulticolor(false);
+        }
+        
         selection_item->polyhedron_item()->polyhedron()->collect_garbage();
         //fix constrained_edges_map
         for(int i=0; i< nE; ++i)
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Join_and_split_polyhedra_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PMP/Join_and_split_polyhedra_plugin.cpp
index fa58b268279..a04801e613c 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Join_and_split_polyhedra_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Join_and_split_polyhedra_plugin.cpp
@@ -244,6 +244,7 @@ void Polyhedron_demo_join_and_split_polyhedra_plugin::on_actionColorConnectedCom
         typedef boost::graph_traits<FaceGraph>::face_descriptor   face_descriptor;
 
         selection_item->polyhedron_item()->setItemIsMulticolor(true);
+        selection_item->polyhedron_item()->computeItemColorVectorAutomatically(true);
         FaceGraph& pmesh = *(selection_item->polyhedron());
 
         boost::property_map<FaceGraph, boost::face_index_t>::type fim
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Mean_curvature_flow_skeleton_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PMP/Mean_curvature_flow_skeleton_plugin.cpp
index fb4ccf514bf..cd7f6c5fbab 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Mean_curvature_flow_skeleton_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Mean_curvature_flow_skeleton_plugin.cpp
@@ -429,6 +429,7 @@ void Polyhedron_demo_mean_curvature_flow_skeleton_plugin::on_actionSegment()
     
   }
   item_segmentation->setItemIsMulticolor(true);
+  item_segmentation->computeItemColorVectorAutomatically(true);
   item_segmentation->setProperty("NbPatchIds", nb_segment); //for join_and_split plugin
   item_segmentation->invalidateOpenGLBuffers();
   scene->addItem(item_segmentation);
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_plane_detection_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_plane_detection_plugin.cpp
index 4fb812dae88..28de24b4acc 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_plane_detection_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_plane_detection_plugin.cpp
@@ -229,6 +229,7 @@ void Polyhedron_demo_mesh_plane_detection_plugin::colorize_segmentation(
                                                                         std::vector<QColor>& color_vector)
 {
   item->setItemIsMulticolor(true);
+  item->computeItemColorVectorAutomatically(true);
   SMesh* sm = item->face_graph();
   color_vector.clear();
   std::size_t max_segment = 0;
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_segmentation_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_segmentation_plugin.cpp
index a4f5d553b81..02b3740984f 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_segmentation_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/Mesh_segmentation_plugin.cpp
@@ -377,7 +377,8 @@ void Polyhedron_demo_mesh_segmentation_plugin::colorize_sdf(
         }
         put(pidmap, *facet_it, static_cast<int>(patch_id));
     }
-    item->setItemIsMulticolor(true, false);
+    item->setItemIsMulticolor(true);
+    item->computeItemColorVectorAutomatically(false);
 }
 
 
@@ -407,6 +408,7 @@ void Polyhedron_demo_mesh_segmentation_plugin::colorize_segmentation(
         color_vector.push_back(aColor);
     }
     item->setItemIsMulticolor(true);
+    item->computeItemColorVectorAutomatically(true);
     item->setProperty("NbPatchIds", static_cast<int>(max_segment + 1)); //for join_and_split plugin
 }
 
diff --git a/Polyhedron/demo/Polyhedron/Scene_polyhedron_selection_item.h b/Polyhedron/demo/Polyhedron/Scene_polyhedron_selection_item.h
index 8791f416e93..ba3617816b1 100644
--- a/Polyhedron/demo/Polyhedron/Scene_polyhedron_selection_item.h
+++ b/Polyhedron/demo/Polyhedron/Scene_polyhedron_selection_item.h
@@ -793,6 +793,7 @@ public:
 
   void setItemIsMulticolor(bool b) {
     poly_item->setItemIsMulticolor(b);
+    poly_item->computeItemColorVectorAutomatically(b);
   }
 
   void selection_changed(bool b);
diff --git a/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.cpp b/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.cpp
index 1f8fb0058f5..0013b1e4313 100644
--- a/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.cpp
@@ -1381,9 +1381,8 @@ bool Scene_surface_mesh_item::intersect_face(double orig_x,
   return false;
 
 }
-void Scene_surface_mesh_item::setItemIsMulticolor(bool b, bool recompute_colors)
+void Scene_surface_mesh_item::setItemIsMulticolor(bool b)
 {
-  this->setProperty("recompute_colors",recompute_colors);
   if(b)
   {
     d->fpatch_id_map = d->smesh_->add_property_map<face_descriptor,int>("f:patch_id", 1).first;
@@ -2219,3 +2218,8 @@ void Scene_surface_mesh_item::copyProperties(Scene_item *item)
   int value = sm_item->alphaSlider()->value();
   alphaSlider()->setValue(value);
 }
+
+void Scene_surface_mesh_item::computeItemColorVectorAutomatically(bool b)
+{
+  this->setProperty("recompute_colors",b);
+}
diff --git a/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.h b/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.h
index b38db8a218f..6f2bc777a61 100644
--- a/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.h
+++ b/Polyhedron/demo/Polyhedron/Scene_surface_mesh_item.h
@@ -68,11 +68,14 @@ public:
 
   QMenu* contextMenu() Q_DECL_OVERRIDE;
 
-  //first bool to set property, second to disable the recomputation of the colors_ vector 
-  //to scale on min_patch value. For example, the Mesh_segmentation_plugin computes the colors_
-  // vector itself, so it must set recompute_colors to false to avoid having it ovewritten 
+  void setItemIsMulticolor(bool);
+  //to be called before invalidate() to enable or disable the recomputation 
+  //of the colors_ vector to scale on min_patch value. 
+  // For example, the Mesh_segmentation_plugin computes the colors_
+  // vector itself, so it must set recompute_colors to false to avoid 
+  // having it ovewritten 
   // in the code of this item.
-  void setItemIsMulticolor(bool, bool recompute_colors = true);
+  void computeItemColorVectorAutomatically(bool);
   bool isItemMulticolor();
   bool hasPatchIds();
   Vertex_selection_map vertex_selection_map();