bigdir/lib/SVG/Graph/BarHorizontal.rb

150 lines
4.3 KiB
Ruby

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