# File lib/gruff/side_stacked_bar.rb, line 12
    def draw_line_markers

      return if @hide_line_markers

      # Draw horizontal line markers and annotate with numbers
      @d = @d.stroke(@marker_color)
      @d = @d.stroke_width 1
      number_of_lines = 5

      # TODO Round maximum marker value to a round number like 100, 0.1, 0.5, etc.
      increment = significant(@maximum_value.to_f / number_of_lines)
      (0..number_of_lines).each do |index|

        line_diff = (@graph_right - @graph_left) / number_of_lines
        x = @graph_right - (line_diff * index) - 1
        @d = @d.line(x, @graph_bottom, x, @graph_top)

        diff = index - number_of_lines
        marker_label = diff.abs * increment

        @d.fill = @marker_color
        @d.font = @font if @font
        @d.stroke = 'transparent'
        @d.pointsize = scale_fontsize(@marker_font_size)
#        @d.gravity = NorthGravity
        @d = @d.annotate_scaled( @base_image, 
                          100, 20,
                          x - (@marker_font_size/1.5), @graph_bottom + 40, 
                          marker_label.to_s, @scale)

      end
    end