diff --git a/src/render/vbo/Render_alternate.cpp b/src/render/vbo/Render_alternate.cpp
index a4a3e79aab0c8d694145c3bd589c978b813fbc8f..fa6974c82630c7406e3dd0d6870342d55d99e93c 100644
--- a/src/render/vbo/Render_alternate.cpp
+++ b/src/render/vbo/Render_alternate.cpp
@@ -1263,8 +1263,11 @@ void Render_alternate::draw_vertical_line(){
 void Render_alternate::update_vertical_line(){
     if (_mouse_pressed_inside_container)
         set_vertical_line(0);
-    else
-        set_vertical_line(render_to_trace_x( screen_to_render_x(_mouse_x)));
+    else {
+        Element_pos d = render_to_trace_x( screen_to_render_x(_mouse_x));
+        set_vertical_line( d );
+        _core->launch_action(_core->_STATE_UPDATE_VARVALUES, &d);//update the value of the variables to display
+    }
     updateGL();
 }