class Gruff::SideStackedBar

New gruff graph type added to enable sideways stacking bar charts (basically looks like a x/y flip of a standard stacking bar chart)

alun.eyre@googlemail.com

Attributes

bar_spacing[RW]

Spacing factor applied between bars

Public Instance Methods

draw() click to toggle source
Calls superclass method Gruff::SideBar#draw
# File lib/gruff/side_stacked_bar.rb, line 17
def draw
  @has_left_labels = true
  get_maximum_by_stack
  super
end

Protected Instance Methods

draw_bars() click to toggle source
# File lib/gruff/side_stacked_bar.rb, line 25
def draw_bars
  # Setup spacing.
  #
  # Columns sit stacked.
  @bar_spacing ||= 0.9

  @bar_width = @graph_height / @column_count.to_f
  @d = @d.stroke_opacity 0.0
  height = Array.new(@column_count, 0)
  length = Array.new(@column_count, @graph_left)
  padding = (@bar_width * (1 - @bar_spacing)) / 2
  if @show_labels_for_bar_values
    label_values = Array.new
    0.upto(@column_count-1) {|i| label_values[i] = {:value => 0, :right_x => 0}}
  end
  @norm_data.each_with_index do |data_row, row_index|
    data_row[DATA_VALUES_INDEX].each_with_index do |data_point, point_index|

        ## using the original calcs from the stacked bar chart to get the difference between
        ## part of the bart chart we wish to stack.
        temp1 = @graph_left + (@graph_width -
                                  data_point * @graph_width - 
                                  height[point_index]) + 1
        temp2 = @graph_left + @graph_width - height[point_index] - 1
        difference = temp2 - temp1

        @d = @d.fill data_row[DATA_COLOR_INDEX]

      left_x = length[point_index] #+ 1
            left_y = @graph_top + (@bar_width * point_index) + padding
        right_x = left_x + difference
            right_y = left_y + @bar_width * @bar_spacing
        length[point_index] += difference
      height[point_index] += (data_point * @graph_width - 2)
      
      if @show_labels_for_bar_values
        label_values[point_index][:value] += @norm_data[row_index][3][point_index]
        label_values[point_index][:right_x] = right_x
      end
              
      # if a data point is 0 it can result in weird really thing lines
      # that shouldn't even be there being drawn on top of the existing
      # bar - this is bad
      if data_point != 0
        @d = @d.rectangle(left_x, left_y, right_x, right_y)
        # Calculate center based on bar_width and current row
      end
      # we still need to draw the labels
      # Calculate center based on bar_width and current row
      label_center = @graph_top + (@bar_width * point_index) + (@bar_width * @bar_spacing / 2.0)
      draw_label(label_center, point_index)
    end

  end
  if @show_labels_for_bar_values
    label_values.each_with_index do |data, i|
      val = (@label_formatting || "%.2f") % data[:value]
      draw_value_label(data[:right_x]+40, (@graph_top + (((i+1) * @bar_width) - (@bar_width / 2)))-12, val.commify, true)
    end
  end
  
  @d.draw(@base_image)    
end
larger_than_max?(data_point, index=0) click to toggle source
# File lib/gruff/side_stacked_bar.rb, line 89
def larger_than_max?(data_point, index=0)
  max(data_point, index) > @maximum_value
end
max(data_point, index) click to toggle source
# File lib/gruff/side_stacked_bar.rb, line 93
def max(data_point, index)
  @data.inject(0) {|sum, item| sum + item[DATA_VALUES_INDEX][index]}
end