diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Smoothing/smoothing_impl.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Smoothing/smoothing_impl.h
index 0fd7fb480a4..199310f4408 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Smoothing/smoothing_impl.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/internal/Smoothing/smoothing_impl.h
@@ -165,14 +165,14 @@ public:
 #endif
     }
 
-    void area_relaxation(const double& precision)
+    void area_relaxation(const double& tolerance)
     {
         std::size_t moved_points = 0;
         BOOST_FOREACH(vertex_descriptor v, vrange_)
         {
              if(!is_border(v, mesh_) && !is_constrained(v))
              {
-                 if (gradient_descent(v, precision))
+                 if (gradient_descent(v, tolerance))
                      moved_points++;
              }
         }
@@ -465,7 +465,7 @@ private:
 
     // gradient descent
     // ----------------
-    bool gradient_descent(const vertex_descriptor& v, const double& precision)
+    bool gradient_descent(const vertex_descriptor& v, const double& tolerance)
     {
         bool move_flag;
         double x, y, z, x_new, y_new, z_new, drdx, drdy, drdz;
@@ -481,14 +481,14 @@ private:
             return false;
 
         double energy_new = 0;
-        double relative_energy = precision + 1;
+        double relative_energy = 1;
         unsigned int t = 1;
         double eta0 = 0.01;
         //double power_t = 0.25;
         double t0 = 0.001;
         double eta = eta0 / (1 + t0*t);
 
-        while(relative_energy > precision)
+        while(relative_energy > tolerance)
         {
             drdx=0, drdy=0, drdz=0;
             compute_derivatives(drdx, drdy, drdz, v, S_av);
diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/smoothing.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/smoothing.h
index e6124ad06ef..68d00f820c1 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/smoothing.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/smoothing.h
@@ -364,7 +364,7 @@ void area_smoothing(PolygonMesh& pmesh, const FaceRange& faces, const NamedParam
     unsigned int nb_iterations = choose_param(get_param(np, internal_np::number_of_iterations), 1);
 
     //gradient descent precision
-    double gd_precision = choose_param(get_param(np, internal_np::gradient_descent_precision), 0.001);
+    double gd_precision = choose_param(get_param(np, internal_np::gradient_descent_precision), 0.000001);
 
     internal::Compatible_remesher<PolygonMesh, VertexPointMap, VCMap, ECMap, GeomTraits>
             remesher(pmesh, vpmap, vcmap, ecmap);
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.cpp
index 3fb13d81503..012a30716b9 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.cpp
@@ -119,6 +119,7 @@ public:
         ui_widget.iterations_spinBox->setSingleStep(1);
         ui_widget.iterations_spinBox->setMinimum(1);
 
+        /*
         ui_widget.curv_iterations_spinBox->setValue(1);
         ui_widget.curv_iterations_spinBox->setSingleStep(1);
         ui_widget.curv_iterations_spinBox->setMinimum(1);
@@ -126,6 +127,7 @@ public:
         ui_widget.curv_iterations_spinBox_2->setValue(1);
         ui_widget.curv_iterations_spinBox_2->setSingleStep(1);
         ui_widget.curv_iterations_spinBox_2->setMinimum(1);
+        */
     }
 
 
@@ -167,8 +169,7 @@ public Q_SLOTS:
         {
             unsigned int nb_iter = ui_widget.Angle_spinBox->value();
             //bool use_weights = ui_widget.use_weights_checkBox->isChecked();
-            angle_smoothing(pmesh,
-                            parameters::number_of_iterations(nb_iter));
+            angle_smoothing(pmesh, parameters::number_of_iterations(nb_iter));
 
             poly_item->invalidateOpenGLBuffers();
             Q_EMIT poly_item->itemChanged();
@@ -176,11 +177,9 @@ public Q_SLOTS:
 
         if(ui_widget.Area_checkBox->isChecked())
         {
-            std::cout<<"Area_checkBox\n";
             unsigned int nb_iter = ui_widget.Area_spinBox->value();
             //double gd_precision = ui_widget.gd_dSpinBox->value();
-            area_smoothing(pmesh,
-                           parameters::number_of_iterations(nb_iter));
+            area_smoothing(pmesh, parameters::number_of_iterations(nb_iter));
 
             poly_item->invalidateOpenGLBuffers();
             Q_EMIT poly_item->itemChanged();
@@ -202,9 +201,9 @@ public Q_SLOTS:
 
         QApplication::setOverrideCursor(Qt::WaitCursor);
 
-        unsigned int nb_iter = ui_widget.curv_iterations_spinBox->value();
-        curvature_flow_smoothing(pmesh,
-                                 parameters::number_of_iterations(nb_iter));
+        //unsigned int nb_iter = ui_widget.curv_iterations_spinBox->value();
+        unsigned int nb_iter = 1;
+        curvature_flow_smoothing(pmesh, parameters::number_of_iterations(nb_iter));
 
         poly_item->invalidateOpenGLBuffers();
         Q_EMIT poly_item->itemChanged();
@@ -226,7 +225,8 @@ public Q_SLOTS:
 
         QApplication::setOverrideCursor(Qt::WaitCursor);
 
-        unsigned int nb_iter = ui_widget.curv_iterations_spinBox_2->value();
+        //unsigned int nb_iter = ui_widget.curv_iterations_spinBox_2->value();
+        unsigned int nb_iter = 1;
 
         if(!is_stiffness_matrix_setup)
         {
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.ui b/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.ui
index ccbc80f3a4c..759e1de3582 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.ui
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Smoothing_plugin.ui
@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>590</width>
-    <height>387</height>
+    <width>570</width>
+    <height>383</height>
    </rect>
   </property>
   <property name="windowTitle">
@@ -19,50 +19,38 @@
      <rect>
       <x>10</x>
       <y>230</y>
-      <width>571</width>
+      <width>551</width>
       <height>121</height>
      </rect>
     </property>
     <property name="title">
      <string>Shape smoothing</string>
     </property>
-    <widget class="QWidget" name="layoutWidget">
+    <widget class="QPushButton" name="MCF_Button">
      <property name="geometry">
       <rect>
-       <x>10</x>
+       <x>160</x>
        <y>40</y>
-       <width>551</width>
-       <height>33</height>
+       <width>211</width>
+       <height>30</height>
       </rect>
      </property>
-     <layout class="QHBoxLayout" name="horizontalLayout_3">
-      <item>
-       <widget class="QPushButton" name="MCF_Button">
-        <property name="text">
-         <string>MCF</string>
-        </property>
-       </widget>
-      </item>
-     </layout>
+     <property name="text">
+      <string>MCF</string>
+     </property>
     </widget>
-    <widget class="QWidget" name="layoutWidget">
+    <widget class="QPushButton" name="modified_MCF_button">
      <property name="geometry">
       <rect>
-       <x>10</x>
+       <x>160</x>
        <y>80</y>
-       <width>551</width>
-       <height>33</height>
+       <width>211</width>
+       <height>30</height>
       </rect>
      </property>
-     <layout class="QHBoxLayout" name="horizontalLayout_4">
-      <item>
-       <widget class="QPushButton" name="modified_MCF_button">
-        <property name="text">
-         <string>Modified MCF</string>
-        </property>
-       </widget>
-      </item>
-     </layout>
+     <property name="text">
+      <string>Modified MCF</string>
+     </property>
     </widget>
    </widget>
    <widget class="QGroupBox" name="Mesh_groupBox">
@@ -70,7 +58,7 @@
      <rect>
       <x>10</x>
       <y>0</y>
-      <width>571</width>
+      <width>551</width>
       <height>227</height>
      </rect>
     </property>
@@ -82,7 +70,7 @@
       <rect>
        <x>10</x>
        <y>30</y>
-       <width>551</width>
+       <width>531</width>
        <height>183</height>
       </rect>
      </property>