bigdir/lib/SVG/Graph/Pie.rb

396 lines
10 KiB
Ruby

require 'SVG/Graph/Graph'
module SVG
module Graph
# === Create presentation quality SVG pie graphs easily
#
# == Synopsis
#
# require 'SVG/Graph/Pie'
#
# fields = %w(Jan Feb Mar)
# data_sales_02 = [12, 45, 21]
#
# graph = SVG::Graph::Pie.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 pie 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, display percent on pie chart,
# title, subtitle etc.
#
# = Examples
#
# http://www.germane-software/repositories/public/SVG/test/single.rb
#
# == See also
#
# * SVG::Graph::Graph
# * SVG::Graph::BarHorizontal
# * SVG::Graph::Bar
# * SVG::Graph::Line
# * 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 Pie < Graph
# Defaults are those set by Graph::initialize, and
# [show_shadow] true
# [shadow_offset] 10
# [show_data_labels] false
# [show_actual_values] false
# [show_percent] true
# [show_key_data_labels] true
# [show_key_actual_values] true
# [show_key_percent] false
# [expanded] false
# [expand_greatest] false
# [expand_gap] 10
# [show_x_labels] false
# [show_y_labels] false
# [datapoint_font_size] 12
def set_defaults
init_with(
:show_shadow => true,
:shadow_offset => 10,
:show_data_labels => false,
:show_actual_values => false,
:show_percent => true,
:show_key_data_labels => true,
:show_key_actual_values => true,
:show_key_percent => false,
:expanded => false,
:expand_greatest => false,
:expand_gap => 10,
:show_x_labels => false,
:show_y_labels => false,
:datapoint_font_size => 12
)
@data = []
end
# Adds a data set to the graph.
#
# graph.add_data( { :data => [1,2,3,4] } )
#
# Note that the :title is not necessary. If multiple
# data sets are added to the graph, the pie chart will
# display the +sums+ of the data. EG:
#
# graph.add_data( { :data => [1,2,3,4] } )
# graph.add_data( { :data => [2,3,5,9] } )
#
# is the same as:
#
# graph.add_data( { :data => [3,5,8,13] } )
def add_data arg
arg[:data].each_index {|idx|
@data[idx] = 0 unless @data[idx]
@data[idx] += arg[:data][idx]
}
end
# If true, displays a drop shadow for the chart
attr_accessor :show_shadow
# Sets the offset of the shadow from the pie chart
attr_accessor :shadow_offset
# If true, display the data labels on the chart
attr_accessor :show_data_labels
# If true, display the actual field values in the data labels
attr_accessor :show_actual_values
# If true, display the percentage value of each pie wedge in the data
# labels
attr_accessor :show_percent
# If true, display the labels in the key
attr_accessor :show_key_data_labels
# If true, display the actual value of the field in the key
attr_accessor :show_key_actual_values
# If true, display the percentage value of the wedges in the key
attr_accessor :show_key_percent
# If true, "explode" the pie (put space between the wedges)
attr_accessor :expanded
# If true, expand the largest pie wedge
attr_accessor :expand_greatest
# The amount of space between expanded wedges
attr_accessor :expand_gap
# The font size of the data point labels
attr_accessor :datapoint_font_size
protected
def add_defs defs
gradient = defs.add_element( "filter", {
"id"=>"dropshadow",
"width" => "1.2",
"height" => "1.2",
} )
gradient.add_element( "feGaussianBlur", {
"stdDeviation" => "4",
"result" => "blur"
})
end
# We don't need the graph
def draw_graph
end
def get_y_labels
[""]
end
def get_x_labels
[""]
end
def keys
total = 0
max_value = 0
@data.each {|x| total += x }
percent_scale = 100.0 / total
count = -1
a = @config[:fields].collect{ |x|
count += 1
v = @data[count]
perc = show_key_percent ? " "+(v * percent_scale).round.to_s+"%" : ""
x + " [" + v.to_s + "]" + perc
}
end
RADIANS = Math::PI/180
def draw_data
@graph = @root.add_element( "g" )
background = @graph.add_element("g")
midground = @graph.add_element("g")
diameter = @graph_height > @graph_width ? @graph_width : @graph_height
diameter -= expand_gap if expanded or expand_greatest
diameter -= datapoint_font_size if show_data_labels
diameter -= 10 if show_shadow
radius = diameter / 2.0
xoff = (width - diameter) / 2
yoff = (height - @border_bottom - diameter)
yoff -= 10 if show_shadow
@graph.attributes['transform'] = "translate( #{xoff} #{yoff} )"
wedge_text_pad = 5
wedge_text_pad = 20 if show_percent and show_data_labels
total = 0
max_value = 0
@data.each {|x|
max_value = max_value < x ? x : max_value
total += x
}
percent_scale = 100.0 / total
prev_percent = 0
rad_mult = 3.6 * RADIANS
@config[:fields].each_index { |count|
value = @data[count]
percent = percent_scale * value
radians = prev_percent * rad_mult
x_start = radius+(Math.sin(radians) * radius)
y_start = radius-(Math.cos(radians) * radius)
radians = (prev_percent+percent) * rad_mult
x_end = radius+(Math.sin(radians) * radius)
x_end -= 0.00001 if @data.length == 1
y_end = radius-(Math.cos(radians) * radius)
path = "M#{radius},#{radius} L#{x_start},#{y_start} "+
"A#{radius},#{radius} "+
"0, #{percent >= 50 ? '1' : '0'},1, "+
"#{x_end} #{y_end} Z"
wedge = @foreground.add_element( "path", {
"d" => path,
"class" => "fill#{count+1}"
})
translate = nil
tx = 0
ty = 0
half_percent = prev_percent + percent / 2
radians = half_percent * rad_mult
if show_shadow
shadow = background.add_element( "path", {
"d" => path,
"filter" => "url(#dropshadow)",
"style" => "fill: #ccc; stroke: none;"
})
clear = midground.add_element( "path", {
"d" => path,
"style" => "fill: #fff; stroke: none;"
})
end
if expanded or (expand_greatest && value == max_value)
tx = (Math.sin(radians) * expand_gap)
ty = -(Math.cos(radians) * expand_gap)
translate = "translate( #{tx} #{ty} )"
wedge.attributes["transform"] = translate
clear.attributes["transform"] = translate if clear
end
if show_shadow
shadow.attributes["transform"] =
"translate( #{tx+shadow_offset} #{ty+shadow_offset} )"
end
if show_data_labels and value != 0
label = ""
label += @config[:fields][count] if show_key_data_labels
label += " ["+value.to_s+"]" if show_actual_values
label += " "+percent.round.to_s+"%" if show_percent
msr = Math.sin(radians)
mcr = Math.cos(radians)
tx = radius + (msr * radius)
ty = radius -(mcr * radius)
if expanded or (expand_greatest && value == max_value)
tx += (msr * expand_gap)
ty -= (mcr * expand_gap)
end
@foreground.add_element( "text", {
"x" => tx.to_s,
"y" => ty.to_s,
"class" => "dataPointLabel",
"style" => "stroke: #fff; stroke-width: 2;"
}).text = label.to_s
@foreground.add_element( "text", {
"x" => tx.to_s,
"y" => ty.to_s,
"class" => "dataPointLabel",
}).text = label.to_s
end
prev_percent += percent
}
end
def round val, to
up = 10**to.to_f
(val * up).to_i / up
end
def get_css
return <<EOL
.dataPointLabel{
fill: #000000;
text-anchor:middle;
font-size: #{datapoint_font_size}px;
font-family: "Arial", sans-serif;
font-weight: normal;
}
/* key - MUST match fill styles */
.key1,.fill1{
fill: #ff0000;
fill-opacity: 0.7;
stroke: none;
stroke-width: 1px;
}
.key2,.fill2{
fill: #0000ff;
fill-opacity: 0.7;
stroke: none;
stroke-width: 1px;
}
.key3,.fill3{
fill-opacity: 0.7;
fill: #00ff00;
stroke: none;
stroke-width: 1px;
}
.key4,.fill4{
fill-opacity: 0.7;
fill: #ffcc00;
stroke: none;
stroke-width: 1px;
}
.key5,.fill5{
fill-opacity: 0.7;
fill: #00ccff;
stroke: none;
stroke-width: 1px;
}
.key6,.fill6{
fill-opacity: 0.7;
fill: #ff00ff;
stroke: none;
stroke-width: 1px;
}
.key7,.fill7{
fill-opacity: 0.7;
fill: #00ff99;
stroke: none;
stroke-width: 1px;
}
.key8,.fill8{
fill-opacity: 0.7;
fill: #ffff00;
stroke: none;
stroke-width: 1px;
}
.key9,.fill9{
fill-opacity: 0.7;
fill: #cc6666;
stroke: none;
stroke-width: 1px;
}
.key10,.fill10{
fill-opacity: 0.7;
fill: #663399;
stroke: none;
stroke-width: 1px;
}
.key11,.fill11{
fill-opacity: 0.7;
fill: #339900;
stroke: none;
stroke-width: 1px;
}
.key12,.fill12{
fill-opacity: 0.7;
fill: #9966FF;
stroke: none;
stroke-width: 1px;
}
EOL
end
end
end
end