X-Git-Url: https://projects.mako.cc/source/selectricity-live/blobdiff_plain/dc635b6d39be19a09a428282b6d639d029908df6..22f84a3ea8bc39eb4cb91575d35dfca683336032:/vendor/plugins/gruff/lib/gruff/bar.rb

diff --git a/vendor/plugins/gruff/lib/gruff/bar.rb b/vendor/plugins/gruff/lib/gruff/bar.rb
new file mode 100644
index 0000000..89eeac7
--- /dev/null
+++ b/vendor/plugins/gruff/lib/gruff/bar.rb
@@ -0,0 +1,84 @@
+
+require File.dirname(__FILE__) + '/base'
+require File.dirname(__FILE__) + '/bar_conversion'
+
+class Gruff::Bar < Gruff::Base
+
+  def draw
+    # Labels will be centered over the left of the bar if
+    # there are more labels than columns. This is basically the same 
+    # as where it would be for a line graph.
+    @center_labels_over_point = (@labels.keys.length > @column_count ? true : false)
+    
+    super
+    return unless @has_data
+
+    draw_bars
+  end
+
+protected
+
+  def draw_bars
+    # Setup spacing.
+    #
+    # Columns sit side-by-side.
+    spacing_factor = 0.9 # space between the bars
+    @bar_width = @graph_width / (@column_count * @data.length).to_f
+
+    @d = @d.stroke_opacity 0.0
+
+    # Setup the BarConversion Object
+    conversion = Gruff::BarConversion.new()
+    conversion.graph_height = @graph_height
+    conversion.graph_top = @graph_top
+
+    # Set up the right mode [1,2,3] see BarConversion for further explanation
+    if @minimum_value >= 0 then
+      # all bars go from zero to positiv
+      conversion.mode = 1
+    else
+      # all bars go from 0 to negativ
+      if @maximum_value <= 0 then
+        conversion.mode = 2
+      else
+        # bars either go from zero to negativ or to positiv
+        conversion.mode = 3
+        conversion.spread = @spread
+        conversion.minimum_value = @minimum_value
+        conversion.zero = -@minimum_value/@spread
+      end
+    end
+
+    # iterate over all normalised data
+    @norm_data.each_with_index do |data_row, row_index|
+
+      data_row[1].each_with_index do |data_point, point_index|
+        # Use incremented x and scaled y
+        # x
+        left_x = @graph_left + (@bar_width * (row_index + point_index + ((@data.length - 1) * point_index)))
+        right_x = left_x + @bar_width * spacing_factor
+        # y
+        conv = []
+        conversion.getLeftYRightYscaled( data_point, conv )
+
+        # create new bar
+        @d = @d.fill data_row[DATA_COLOR_INDEX]
+        @d = @d.rectangle(left_x, conv[0], right_x, conv[1])
+
+        # Calculate center based on bar_width and current row
+        label_center = @graph_left + 
+                      (@data.length * @bar_width * point_index) + 
+                      (@data.length * @bar_width / 2.0)
+        # Subtract half a bar width to center left if requested
+        draw_label(label_center - (@center_labels_over_point ? @bar_width / 2.0 : 0.0), point_index)
+      end
+
+    end
+
+    # Draw the last label if requested
+    draw_label(@graph_right, @column_count) if @center_labels_over_point
+
+    @d.draw(@base_image)
+  end
+
+end