2D Donut Shading

[Ruby On Rails Version - Controller] app/controllers/donutshading_controller.rb

require("chartdirector")

class DonutshadingController < ApplicationController

    def index()
        @title = "2D Donut Shading"
        @ctrl_file = File.expand_path(__FILE__)
        @noOfCharts = 7
        render :template => "templates/chartview"
    end

    #
    # Render and deliver the chart
    #
    def getchart()
        # This script can draw different charts depending on the chartIndex
        chartIndex = (params["img"]).to_i

        # The data for the pie chart
        data = [18, 30, 20, 15]

        # The colors to use for the sectors
        colors = [0x66aaee, 0xeebb22, 0xbbbbbb, 0x8844ff]

        # Create a PieChart object of size 200 x 220 pixels. Use a vertical gradient color from blue
        # (0000cc) to deep blue (000044) as background. Use rounded corners of 16 pixels radius.
        c = ChartDirector::PieChart.new(200, 220)
        c.setBackground(c.linearGradientColor(0, 0, 0, c.getHeight(), 0x0000cc, 0x000044))
        c.setRoundedFrame(0xffffff, 16)

        # Set donut center at (100, 120), and outer/inner radii as 80/40 pixels
        c.setDonutSize(100, 120, 80, 40)

        # Set the pie data
        c.setData(data)

        # Set the sector colors
        c.setColors2(ChartDirector::DataColor, colors)

        # Demonstrates various shading modes
        if chartIndex == 0
            c.addTitle("Default Shading", "bold", 12, 0xffffff)
        elsif chartIndex == 1
            c.addTitle("Local Gradient", "bold", 12, 0xffffff)
            c.setSectorStyle(ChartDirector::LocalGradientShading)
        elsif chartIndex == 2
            c.addTitle("Global Gradient", "bold", 12, 0xffffff)
            c.setSectorStyle(ChartDirector::GlobalGradientShading)
        elsif chartIndex == 3
            c.addTitle("Concave Shading", "bold", 12, 0xffffff)
            c.setSectorStyle(ChartDirector::ConcaveShading)
        elsif chartIndex == 4
            c.addTitle("Rounded Edge", "bold", 12, 0xffffff)
            c.setSectorStyle(ChartDirector::RoundedEdgeShading)
        elsif chartIndex == 5
            c.addTitle("Radial Gradient", "bold", 12, 0xffffff)
            c.setSectorStyle(ChartDirector::RadialShading)
        elsif chartIndex == 6
            c.addTitle("Ring Shading", "bold", 12, 0xffffff)
            c.setSectorStyle(ChartDirector::RingShading)
        end

        # Disable the sector labels by setting the color to Transparent
        c.setLabelStyle("", 8, ChartDirector::Transparent)

        # Output the chart
        send_data(c.makeChart2(ChartDirector::PNG), :type => "image/png", :disposition => "inline")

    end

end

[Ruby On Rails Version - View] app/views/templates/chartview.html.erb

<html>
<body style="margin:5px 0px 0px 5px">

<!-- Title -->
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    <%= @title %>
</div>
<hr style="border:solid 1px #000080" />

<!-- Source Code Listing Link -->
<div style="font-size:9pt; font-family:verdana; margin-bottom:1.5em">
    <%= link_to "Source Code Listing", 
        :controller => "cddemo", :action => "viewsource",
        :ctrl_file => @ctrl_file, :view_file => File.expand_path(__FILE__) %>
</div>

<!-- Create one or more IMG tags to display the demo chart(s) -->
<% 0.upto(@noOfCharts - 1) do |i| %>
    <img src="<%= url_for(:action => "getchart", :img => i) %>">
<% end %>

</body>
</html>

[Command Line Version] rubydemo/donutshading.rb

#!/usr/bin/env ruby
require("chartdirector")

def createChart(chartIndex)

    # The data for the pie chart
    data = [18, 30, 20, 15]

    # The colors to use for the sectors
    colors = [0x66aaee, 0xeebb22, 0xbbbbbb, 0x8844ff]

    # Create a PieChart object of size 200 x 220 pixels. Use a vertical gradient color from blue
    # (0000cc) to deep blue (000044) as background. Use rounded corners of 16 pixels radius.
    c = ChartDirector::PieChart.new(200, 220)
    c.setBackground(c.linearGradientColor(0, 0, 0, c.getHeight(), 0x0000cc, 0x000044))
    c.setRoundedFrame(0xffffff, 16)

    # Set donut center at (100, 120), and outer/inner radii as 80/40 pixels
    c.setDonutSize(100, 120, 80, 40)

    # Set the pie data
    c.setData(data)

    # Set the sector colors
    c.setColors2(ChartDirector::DataColor, colors)

    # Demonstrates various shading modes
    if chartIndex == 0
        c.addTitle("Default Shading", "bold", 12, 0xffffff)
    elsif chartIndex == 1
        c.addTitle("Local Gradient", "bold", 12, 0xffffff)
        c.setSectorStyle(ChartDirector::LocalGradientShading)
    elsif chartIndex == 2
        c.addTitle("Global Gradient", "bold", 12, 0xffffff)
        c.setSectorStyle(ChartDirector::GlobalGradientShading)
    elsif chartIndex == 3
        c.addTitle("Concave Shading", "bold", 12, 0xffffff)
        c.setSectorStyle(ChartDirector::ConcaveShading)
    elsif chartIndex == 4
        c.addTitle("Rounded Edge", "bold", 12, 0xffffff)
        c.setSectorStyle(ChartDirector::RoundedEdgeShading)
    elsif chartIndex == 5
        c.addTitle("Radial Gradient", "bold", 12, 0xffffff)
        c.setSectorStyle(ChartDirector::RadialShading)
    elsif chartIndex == 6
        c.addTitle("Ring Shading", "bold", 12, 0xffffff)
        c.setSectorStyle(ChartDirector::RingShading)
    end

    # Disable the sector labels by setting the color to Transparent
    c.setLabelStyle("", 8, ChartDirector::Transparent)

    # Output the chart
    c.makeChart("donutshading%s.png" % chartIndex)
end

createChart(0)
createChart(1)
createChart(2)
createChart(3)
createChart(4)
createChart(5)
createChart(6)