def draw_line_markers
return if @hide_line_markers
@d = @d.stroke_antialias false
@d = @d.stroke(@marker_color)
@d = @d.stroke_width 1
if @y_axis_increment
increment = @y_axis_increment
number_of_lines = (@spread / @y_axis_increment).to_i
else
if @marker_count.nil?
(3..7).each do |lines|
if @spread % lines == 0.0
@marker_count = lines
break
end
end
@marker_count ||= 5
end
@increment = (@spread > 0 && @marker_count > 0) ? significant(@spread / @marker_count) : 1
number_of_lines = @marker_count
increment = @increment
end
(0..number_of_lines).each do |index|
marker_label = @minimum_value + index * increment
x = @graph_left + (marker_label - @minimum_value) * @graph_width / @spread
@d = @d.line(x, @graph_bottom, x, @graph_bottom + 0.5 * LABEL_MARGIN)
unless @hide_line_numbers
@d.fill = @font_color
@d.font = @font if @font
@d.stroke = 'transparent'
@d.pointsize = scale_fontsize(@marker_font_size)
@d.gravity = CenterGravity
@d = @d.annotate_scaled(@base_image,
0, 0,
x, @graph_bottom + (LABEL_MARGIN * 2.0),
label(marker_label, increment), @scale)
end
@d = @d.stroke_antialias true
end
end