Rectangular Angular Meters

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

require("chartdirector")

class RectangularmeterController < ApplicationController

    def index()
        @title = "Rectangular Angular Meters"
        @ctrl_file = File.expand_path(__FILE__)
        @noOfCharts = 6
        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 value to display on the meter
        value = 72.55

        # Create an AngularMeter object of size 240 x 170 pixels with very light grey (0xeeeeee)
        # background, and a rounded 4-pixel thick light grey (0xcccccc) border
        m = ChartDirector::AngularMeter.new(240, 170, 0xeeeeee, 0xcccccc)
        m.setRoundedFrame(ChartDirector::Transparent)
        m.setThickFrame(4)

        # Set the default text and line colors to dark grey (0x222222)
        m.setColor(ChartDirector::TextColor, 0x222222)
        m.setColor(ChartDirector::LineColor, 0x222222)

        # Center at (120, 145), scale radius = 128 pixels, scale angle -60 to +60 degrees
        m.setMeter(120, 145, 128, -60, 60)

        # Meter scale is 0 - 100, with major/minor/micro ticks every 20/10/5 units
        m.setScale(0, 100, 20, 10, 5)

        # Set the scale label style to 14pt Arial Italic. Set the major/minor/micro tick lengths to
        # 16/16/10 pixels pointing inwards, and their widths to 2/1/1 pixels.
        m.setLabelStyle("ariali.ttf", 14)
        m.setTickLength(-16, -16, -10)
        m.setLineWidth(0, 2, 1, 1)

        # Demostrate different types of color scales and putting them at different positions
        smoothColorScale = [0, 0x3333ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100, 0xff0000]
        stepColorScale = [0, 0x00cc00, 60, 0xffdd00, 80, 0xee0000, 100]
        highLowColorScale = [0, 0x00ff00, 70, ChartDirector::Transparent, 100, 0xff0000]

        if chartIndex == 0
            # Add the smooth color scale at the default position
            m.addColorScale(smoothColorScale)
        elsif chartIndex == 1
            # Add the smooth color scale starting at radius 128 with zero width and ending at radius
            # 128 with 16 pixels inner width
            m.addColorScale(smoothColorScale, 128, 0, 128, -16)
        elsif chartIndex == 2
            # Add the smooth color scale starting at radius 70 with zero width and ending at radius
            # 60 with 20 pixels outer width
            m.addColorScale(smoothColorScale, 70, 0, 60, 20)
        elsif chartIndex == 3
            # Add the high/low color scale at the default position
            m.addColorScale(highLowColorScale)
        elsif chartIndex == 4
            # Add the step color scale at the default position
            m.addColorScale(stepColorScale)
        else
            # Add the smooth color scale at radius 60 with 15 pixels outer width
            m.addColorScale(smoothColorScale, 60, 15)
        end

        # Add a text label centered at (120, 120) with 15pt Arial Italic font
        m.addText(120, 120, "CPU", "ariali.ttf", 15, ChartDirector::TextColor,
            ChartDirector::BottomCenter)

        # Add a red (0xff0000) pointer at the specified value
        m.addPointer2(value, 0xff0000)

        # Add a semi-transparent light grey (0x3fcccccc) rectangle at (0, 120) and of size 240 x 60
        # pixels to cover the bottom part of the meter for decoration
        cover = m.addText(0, 120, "")
        cover.setSize(240, 60)
        cover.setBackground(0x3fcccccc)

        # Output the chart
        send_data(m.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/rectangularmeter.rb

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

def createChart(chartIndex)

    # The value to display on the meter
    value = 72.55

    # Create an AngularMeter object of size 240 x 170 pixels with very light grey (0xeeeeee)
    # background, and a rounded 4-pixel thick light grey (0xcccccc) border
    m = ChartDirector::AngularMeter.new(240, 170, 0xeeeeee, 0xcccccc)
    m.setRoundedFrame(ChartDirector::Transparent)
    m.setThickFrame(4)

    # Set the default text and line colors to dark grey (0x222222)
    m.setColor(ChartDirector::TextColor, 0x222222)
    m.setColor(ChartDirector::LineColor, 0x222222)

    # Center at (120, 145), scale radius = 128 pixels, scale angle -60 to +60 degrees
    m.setMeter(120, 145, 128, -60, 60)

    # Meter scale is 0 - 100, with major/minor/micro ticks every 20/10/5 units
    m.setScale(0, 100, 20, 10, 5)

    # Set the scale label style to 14pt Arial Italic. Set the major/minor/micro tick lengths to
    # 16/16/10 pixels pointing inwards, and their widths to 2/1/1 pixels.
    m.setLabelStyle("ariali.ttf", 14)
    m.setTickLength(-16, -16, -10)
    m.setLineWidth(0, 2, 1, 1)

    # Demostrate different types of color scales and putting them at different positions
    smoothColorScale = [0, 0x3333ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100, 0xff0000]
    stepColorScale = [0, 0x00cc00, 60, 0xffdd00, 80, 0xee0000, 100]
    highLowColorScale = [0, 0x00ff00, 70, ChartDirector::Transparent, 100, 0xff0000]

    if chartIndex == 0
        # Add the smooth color scale at the default position
        m.addColorScale(smoothColorScale)
    elsif chartIndex == 1
        # Add the smooth color scale starting at radius 128 with zero width and ending at radius 128
        # with 16 pixels inner width
        m.addColorScale(smoothColorScale, 128, 0, 128, -16)
    elsif chartIndex == 2
        # Add the smooth color scale starting at radius 70 with zero width and ending at radius 60
        # with 20 pixels outer width
        m.addColorScale(smoothColorScale, 70, 0, 60, 20)
    elsif chartIndex == 3
        # Add the high/low color scale at the default position
        m.addColorScale(highLowColorScale)
    elsif chartIndex == 4
        # Add the step color scale at the default position
        m.addColorScale(stepColorScale)
    else
        # Add the smooth color scale at radius 60 with 15 pixels outer width
        m.addColorScale(smoothColorScale, 60, 15)
    end

    # Add a text label centered at (120, 120) with 15pt Arial Italic font
    m.addText(120, 120, "CPU", "ariali.ttf", 15, ChartDirector::TextColor,
        ChartDirector::BottomCenter)

    # Add a red (0xff0000) pointer at the specified value
    m.addPointer2(value, 0xff0000)

    # Add a semi-transparent light grey (0x3fcccccc) rectangle at (0, 120) and of size 240 x 60
    # pixels to cover the bottom part of the meter for decoration
    cover = m.addText(0, 120, "")
    cover.setSize(240, 60)
    cover.setBackground(0x3fcccccc)

    # Output the chart
    m.makeChart("rectangularmeter%s.png" % chartIndex)
end

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