# File gtk/sample/gtk-demo/cairo-curve-to.rb, line 28
    def draw(cr)
      cr.move_to(X, Y)
      cr.curve_to(X1, Y1, X2, Y2, X3, Y3)
      
      cr.stroke
      
      cr.set_source_rgba(1, 0.2, 0.2, 0.6)
      cr.set_line_width(0.03)
      cr.move_to(X, Y)
      cr.line_to(X1, Y1)
      cr.move_to(X2, Y2)
      cr.line_to(X3, Y3)
      cr.stroke
    end