diff --git a/AABB_tree/demo/AABB_tree/Scene.h b/AABB_tree/demo/AABB_tree/Scene.h
index 092e5dc9070..5ee0948cf1c 100644
--- a/AABB_tree/demo/AABB_tree/Scene.h
+++ b/AABB_tree/demo/AABB_tree/Scene.h
@@ -16,6 +16,7 @@
 #include <CGAL/AABB_face_graph_triangle_primitive.h>
 
 #include <QtCore/qglobal.h>
+#include <QMap>
 #include <QGLViewer/manipulatedFrame.h>
 #include <QGLViewer/qglviewer.h>
 #include <QOpenGLFunctions_2_1>
diff --git a/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h b/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h
index c43cd939aec..b8d957755d2 100644
--- a/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h
+++ b/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h
@@ -22,7 +22,7 @@
 
 #include <QApplication>
 #include <QKeyEvent>
-
+#include <QMap>
 #include <QGLViewer/qglviewer.h>
 #include <QKeyEvent>
 #include <QOpenGLFunctions_2_1>
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Clip_polyhedron_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Clip_polyhedron_plugin.cpp
index 3f87c1c71f8..7fab394ba07 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Clip_polyhedron_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/Clip_polyhedron_plugin.cpp
@@ -194,7 +194,7 @@ public Q_SLOTS:
                                               plane->plane(),
                                               ui_widget.close_checkBox->isChecked());
           poly->invalidateOpenGLBuffers();
-          viewer->updateGL();
+
         }
         else
         {
@@ -223,10 +223,9 @@ public Q_SLOTS:
           new_item->setVisible(poly->visible());
           scene->addItem(new_item);
           new_item->invalidateOpenGLBuffers();
-
-          viewer->updateGL();
         }
       }
+      viewer->update();
     }
     QApplication::restoreOverrideCursor();
   }
diff --git a/Triangulation_3/demo/Triangulation_3/Scene.h b/Triangulation_3/demo/Triangulation_3/Scene.h
index 2401e336c3c..2b0c2e0a8e3 100644
--- a/Triangulation_3/demo/Triangulation_3/Scene.h
+++ b/Triangulation_3/demo/Triangulation_3/Scene.h
@@ -2,6 +2,7 @@
 #define SCENE_H
 
 #include "typedefs.h"
+#include <QMap>
 #include <QGLViewer/qglviewer.h>
 
 class Scene {