def line(start_x, start_y, end_x, end_y)
      primitive 'line ' + format('%g,%g %g,%g', start_x, start_y, end_x, end_y)
    end
def line(start_x, start_y, end_x, end_y)
      primitive 'line ' + format('%g,%g %g,%g', start_x, start_y, end_x, end_y)
    end
Draw a line