GtkVRuler A vertical ruler. The VRuler widget is a widget arranged vertically creating a ruler that is utilized around other widgets such as a text widget. The ruler is used to show the location of the mouse on the window and to show the size of the window in specified units. The available units of measurement are GTK_PIXELS, GTK_INCHES and GTK_CENTIMETERS. GTK_PIXELS is the default. rulers. The #GtkVRuler struct contains private data and should be accessed using the functions below. @ruler: Creates a new vertical ruler @Returns: the new GTKVRuler.