diff --git a/Polygon_mesh_processing/examples/Polygon_mesh_processing/corefinement_mesh_union.cpp b/Polygon_mesh_processing/examples/Polygon_mesh_processing/corefinement_mesh_union.cpp
index 4eca64f63de..205cc39708c 100644
--- a/Polygon_mesh_processing/examples/Polygon_mesh_processing/corefinement_mesh_union.cpp
+++ b/Polygon_mesh_processing/examples/Polygon_mesh_processing/corefinement_mesh_union.cpp
@@ -43,6 +43,40 @@ struct Visitor_rep{
     }
   }
 
+  void start_coplanar_faces(int tc)
+  {
+    std::cout << "Visitor::start_coplanar_faces() at " << t.time() << " sec." << std::endl;
+    tcoplanar= tc;
+    count_coplanar = 0;
+    bound_coplanar = tcoplanar/10;
+  }
+
+  void coplanar_faces_step()
+  {
+    ++count_coplanar;
+    if(count_coplanar> bound_coplanar){
+      std::cout << "Visitor::coplanar_faces: " << double(count_coplanar)/double(tcoplanar) * 100  << " % " << std::endl;
+      bound_coplanar += tcoplanar/10;
+    }
+  }
+
+  void start_intersection_points(int ti)
+  {
+    std::cout << "Visitor::start_intersection_points() at " << t.time() << " sec." << std::endl;
+    tintersection= ti;
+    count_intersection = 0;
+    bound_intersection = tintersection/10;
+  }
+
+  void intersection_points_step()
+  {
+    ++count_intersection;
+    if(count_intersection> bound_intersection){
+      std::cout << "Visitor::intersection_points: " << double(count_intersection)/double(tintersection) * 100  << " % " << std::endl;
+      bound_intersection += tintersection/10;
+    }
+  }
+
   double time() const
   {
     return t.time();
@@ -55,6 +89,14 @@ struct Visitor_rep{
 
   int bound_faces = 0;
   int tfaces = 0;
+
+  int bound_coplanar = 0;
+  int tcoplanar = 0;
+  int count_coplanar = 0;
+
+  int bound_intersection = 0;
+  int tintersection = 0;
+  int count_intersection = 0;
   CGAL::Timer t;
 };
 
@@ -75,16 +117,16 @@ struct Visitor :
 
   void start_filter_intersections() const
   {
-    std::cout << "Visitor::start_filter_intersections() at " << sptr->time() << std::endl;
+    std::cout << "Visitor::start_filter_intersections() at " << sptr->time() << " sec." << std::endl;
   }
   void end_filter_intersections() const
   {
-    std::cout << "Visitor::end_filter_intersections() at " << sptr->time()  << std::endl;
+    std::cout << "Visitor::end_filter_intersections() at " << sptr->time() << " sec."  << std::endl;
   }
 
   void start_triangulation(int tf)const
   {
-    std::cout << "Visitor::start_triangulation() with " << tf << " faces at " << sptr->time()  << std::endl;
+    std::cout << "Visitor::start_triangulation() with " << tf << " faces at " << sptr->time() << " sec."  << std::endl;
     sptr->start_triangulation(tf);
   }
 
@@ -95,37 +137,52 @@ struct Visitor :
 
   void end_triangulation()const
   {
-    std::cout << "Visitor::end_triangulation() at " << sptr->time()  << std::endl;
+    std::cout << "Visitor::end_triangulation() at " << sptr->time() << " sec."  << std::endl;
   }
 
-  void start_coplanar_faces(int) const
+  void start_coplanar_faces(int i) const
   {
-    std::cout << "Visitor::start_coplanar_faces() at " << sptr->time() << std::endl;
+    sptr->start_coplanar_faces(i);
   }
 
   void coplanar_faces_step() const
   {
-    std::cout << "Visitor::coplanar_faces_step() at " << sptr->time() << std::endl;
+    sptr->coplanar_faces_step();
   }
 
   void end_coplanar_faces() const
   {
-    std::cout << "Visitor::end_coplanar_faces() at " << sptr->time() << std::endl;
+    std::cout << "Visitor::end_coplanar_faces() at " << sptr->time() << " sec." << std::endl;
+  }
+
+  void start_intersection_points(int i) const
+  {
+    sptr->start_intersection_points(i);
+  }
+
+  void intersection_points_step() const
+  {
+    sptr->intersection_points_step();
+  }
+
+  void end_intersection_points() const
+  {
+    std::cout << "Visitor::end_intersection_points() at " << sptr->time() << " sec." << std::endl;
   }
 
   void start_build_output() const
   {
-    std::cout << "Visitor::start_build_output() at " << sptr->time() << std::endl;
+    std::cout << "Visitor::start_build_output() at " << sptr->time()  << " sec."<< std::endl;
   }
 
   void build_output_step() const
   {
-    std::cout << "Visitor::build_output_step() at " << sptr->time() << std::endl;
+    std::cout << "Visitor::build_output_step() at " << sptr->time() << " sec." << std::endl;
   }
 
   void end_build_output() const
   {
-    std::cout << "Visitor::end_build_output() at " << sptr->time() << std::endl;
+    std::cout << "Visitor::end_build_output() at " << sptr->time() << " sec." << std::endl;
   }
 };
 
@@ -146,10 +203,10 @@ int main(int argc, char* argv[])
   t.start();
   Mesh out;
   Visitor visitor;
-  // PMP::corefine(mesh1,mesh2, CGAL::parameters::visitor(visitor));
+
   bool valid_union = PMP::corefine_and_compute_union (mesh1,mesh2, out, CGAL::parameters::visitor(visitor));
 
-  std::cout << "total time = " << t.time() << std::endl;
+  std::cout << "Global timer = " << t.time() << " sec." << std::endl;
 
 
   if(valid_union)
diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/Visitor.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/Visitor.h
index 423593d9802..91c01dfe077 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/Visitor.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/Visitor.h
@@ -570,19 +570,19 @@ public:
   }
 
 
-  void start_build_output() const
+  void start_intersection_points(int i) const
   {
-    user_visitor.start_build_output();
+    user_visitor.start_intersection_points(i);
   }
 
-  void build_output_step() const
+  void intersection_points_step() const
   {
-    user_visitor.build_output_step();
+    user_visitor.intersection_points_step();
   }
 
-  void end_build_output() const
+  void end_intersection_points() const
   {
-    user_visitor.end_build_output();
+    user_visitor.end_intersection_points();
   }
 
   void start_coplanar_faces(int i) const
@@ -600,6 +600,21 @@ public:
     user_visitor.end_coplanar_faces();
   }
 
+  void start_build_output() const
+  {
+    user_visitor.start_build_output();
+  }
+
+  void build_output_step() const
+  {
+    user_visitor.build_output_step();
+  }
+
+  void end_build_output() const
+  {
+    user_visitor.end_build_output();
+  }
+
   void
   set_non_manifold_feature_map(
     const TriangleMesh& tm,
diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/face_graph_utils.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/face_graph_utils.h
index dd28d320d27..68026bf86c2 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/face_graph_utils.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/face_graph_utils.h
@@ -465,15 +465,23 @@ struct Default_visitor{
   void start_filter_intersections() const {}
   void progress_filter_intersection(double ) const {}
   void end_filter_intersections() const {}
+
   void start_triangulation(int) const {}
   void progress_triangulation(int) const {}
   void end_triangulation() const {}
+
+  void start_coplanar_faces(int) const {}
+  void coplanar_faces_step() const {}
+  void end_coplanar_faces() const {}
+
+  void start_intersection_points(int) const {}
+  void intersection_points_step() const {}
+  void end_intersection_points() const {}
+
   void start_build_output() const {}
   void build_output_step() const {}
   void end_build_output() const {}
-  void start_coplanar_faces() const {}
-  void coplanar_faces_step() const {}
-  void end_coplanar_faces() const {}
+
 
   // calls commented in the code and probably incomplete due to the migration
   // see NODE_VISITOR_TAG
diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/intersection_impl.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/intersection_impl.h
index f492459b988..502541248e8 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/intersection_impl.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Corefinement/intersection_impl.h
@@ -854,10 +854,12 @@ class Intersection_of_triangle_meshes
   {
     typedef std::tuple<Intersection_type, halfedge_descriptor, bool,bool>  Inter_type;
 
+    visitor.start_intersection_points(tm1_edge_to_tm2_faces.size());
 
     for(typename Edge_to_faces::iterator it=tm1_edge_to_tm2_faces.begin();
                                          it!=tm1_edge_to_tm2_faces.end();++it)
     {
+      visitor.intersection_points_step();
       edge_descriptor e_1=it->first;
 
       halfedge_descriptor h_1=halfedge(e_1,tm1);
@@ -1076,6 +1078,7 @@ class Intersection_of_triangle_meshes
       } // end loop on all faces that intersect the edge
     } // end loop on all entries (edges) in 'edge_to_face'
     CGAL_assertion(nodes.size()==unsigned(current_node+1));
+    visitor.end_intersection_points();
   }
 
   struct Graph_node{