Ruler widgets are used to indicate the location of the mouse
pointer in a given window. A window can have a vertical ruler
spanning across the width and a horizontal ruler spanning down the
height. A small triangular indicator on the ruler shows the exact
location of the pointer relative to the ruler.
GTK.Hruler()->set_metric(GTK.PIXELS)->set_range(0.0,100.0,50.0,100.0)->draw_ticks()->draw_pos()->set_usize(300,30)
GTK.Hruler()->set_metric(GTK.CENTIMETERS)->set_range(0.0,100.0,50.0,100.0)->draw_ticks()->draw_pos()->set_usize(300,30)
GTK.Hruler()->set_usize(300,30)