Chris@0: require 'rexml/document'
Chris@0: require 'SVG/Graph/BarBase'
Chris@0: 
Chris@0: module SVG
Chris@0:   module Graph
Chris@0:     # === Create presentation quality SVG horitonzal bar graphs easily
Chris@0:     # 
Chris@0:     # = Synopsis
Chris@0:     # 
Chris@0:     #   require 'SVG/Graph/BarHorizontal'
Chris@0:     #   
Chris@0:     #   fields = %w(Jan Feb Mar)
Chris@0:     #   data_sales_02 = [12, 45, 21]
Chris@0:     #   
Chris@0:     #   graph = SVG::Graph::BarHorizontal.new({
Chris@0:     #     :height => 500,
Chris@0:     #     :width => 300,
Chris@0:     #     :fields => fields,
Chris@0:     #   })
Chris@0:     #   
Chris@0:     #   graph.add_data({
Chris@0:     #     :data => data_sales_02,
Chris@0:     #     :title => 'Sales 2002',
Chris@0:     #   })
Chris@0:     #   
Chris@0:     #   print "Content-type: image/svg+xml\r\n\r\n"
Chris@0:     #   print graph.burn
Chris@0:     # 
Chris@0:     # = Description
Chris@0:     # 
Chris@0:     # This object aims to allow you to easily create high quality
Chris@0:     # SVG horitonzal bar graphs. You can either use the default style sheet
Chris@0:     # or supply your own. Either way there are many options which can
Chris@0:     # be configured to give you control over how the graph is
Chris@0:     # generated - with or without a key, data elements at each point,
Chris@0:     # title, subtitle etc.
Chris@0:     # 
Chris@0:     # = Examples
Chris@0:     # 
Chris@0:     # * http://germane-software.com/repositories/public/SVG/test/test.rb
Chris@0:     # 
Chris@0:     # = See also
Chris@0:     # 
Chris@0:     # * SVG::Graph::Graph
Chris@0:     # * SVG::Graph::Bar
Chris@0:     # * SVG::Graph::Line
Chris@0:     # * SVG::Graph::Pie
Chris@0:     # * SVG::Graph::Plot
Chris@0:     # * SVG::Graph::TimeSeries
Chris@0:     #
Chris@0:     # == Author
Chris@0:     #
Chris@0:     # Sean E. Russell <serATgermaneHYPHENsoftwareDOTcom>
Chris@0:     #
Chris@0:     # Copyright 2004 Sean E. Russell
Chris@0:     # This software is available under the Ruby license[LICENSE.txt]
Chris@0:     #
Chris@0:     class BarHorizontal < BarBase
Chris@0:       # In addition to the defaults set in BarBase::set_defaults, sets
Chris@0:       # [rotate_y_labels] true
Chris@0:       # [show_x_guidelines] true
Chris@0:       # [show_y_guidelines] false
Chris@0:       def set_defaults
Chris@0:         super
Chris@0:         init_with( 
Chris@0:           :rotate_y_labels    => true,
Chris@0:           :show_x_guidelines  => true,
Chris@0:           :show_y_guidelines  => false
Chris@0:         )
Chris@0:         self.right_align = self.right_font = 1
Chris@0:       end
Chris@0:   
Chris@0:       protected
Chris@0: 
Chris@0:       def get_x_labels
Chris@0:         maxvalue = max_value
Chris@0:         minvalue = min_value
Chris@0:         range = maxvalue - minvalue
Chris@0:         top_pad = range == 0 ? 10 : range / 20.0
Chris@0:         scale_range = (maxvalue + top_pad) - minvalue
Chris@0: 
Chris@0:         scale_division = scale_divisions || (scale_range / 10.0)
Chris@0: 
Chris@0:         if scale_integers
Chris@0:           scale_division = scale_division < 1 ? 1 : scale_division.round
Chris@0:         end
Chris@0: 
Chris@0:         rv = []
Chris@0:         maxvalue = maxvalue%scale_division == 0 ? 
Chris@0:           maxvalue : maxvalue + scale_division
Chris@0:         minvalue.step( maxvalue, scale_division ) {|v| rv << v}
Chris@0:         return rv
Chris@0:       end
Chris@0: 
Chris@0:       def get_y_labels
Chris@0:         @config[:fields]
Chris@0:       end
Chris@0: 
Chris@0:       def y_label_offset( height )
Chris@0:         height / -2.0
Chris@0:       end
Chris@0: 
Chris@0:       def draw_data
Chris@0:         minvalue = min_value
Chris@0:         fieldheight = field_height
Chris@0: 
Chris@0:         unit_size = (@graph_width.to_f - font_size*2*right_font ) /
Chris@0:                         (get_x_labels.max - get_x_labels.min )
Chris@0:         bargap = bar_gap ? (fieldheight < 10 ? fieldheight / 2 : 10) : 0
Chris@0: 
Chris@0:         bar_height = fieldheight - bargap
Chris@0:         bar_height /= @data.length if stack == :side
Chris@0:         y_mod = (bar_height / 2) + (font_size / 2)
Chris@0:         
Chris@0:         field_count = 1
Chris@0:         @config[:fields].each_index { |i|
Chris@0:           dataset_count = 0
Chris@0:           for dataset in @data
Chris@0:             value = dataset[:data][i]
Chris@0:             
Chris@0:             top = @graph_height - (fieldheight * field_count)
Chris@0:             top += (bar_height * dataset_count) if stack == :side
Chris@0:             # cases (assume 0 = +ve):
Chris@0:             #   value  min  length          left
Chris@0:             #    +ve   +ve  value.abs - min minvalue.abs
Chris@0:             #    +ve   -ve  value.abs - 0   minvalue.abs
Chris@0:             #    -ve   -ve  value.abs - 0   minvalue.abs + value
Chris@0:             length = (value.abs - (minvalue > 0 ? minvalue : 0)) * unit_size
Chris@0:             left = (minvalue.abs + (value < 0 ? value : 0)) * unit_size
Chris@0: 
Chris@0:             @graph.add_element( "rect", {
Chris@0:               "x" => left.to_s,
Chris@0:               "y" => top.to_s,
Chris@0:               "width" => length.to_s,
Chris@0:               "height" => bar_height.to_s,
Chris@0:               "class" => "fill#{dataset_count+1}"
Chris@0:             })
Chris@0: 
Chris@0:             make_datapoint_text( 
Chris@0:               left+length+5, top+y_mod, value, "text-anchor: start; "
Chris@0:               )
Chris@0:             dataset_count += 1
Chris@0:           end
Chris@0:           field_count += 1
Chris@0:         }
Chris@0:       end
Chris@0:     end
Chris@0:   end
Chris@0: end