Fix of interaction between opengl contexts and main page notebook

xs/xsp/GUI_3DScene.xsp

@@ -190,6 +190,11 @@ remove_all_canvases()
     CODE:
         _3DScene::remove_all_canvases();
 
+void
+reset_current_canvas()
+    CODE:
+        _3DScene::reset_current_canvas();
+
 void
 set_active(canvas, active)
         SV   *canvas;