ChartDirector 6.0 (Python Edition)

Round Meter




This example demonstrates the basic steps in creating a round meter.

A round meter can be created with the following steps:

Source Code Listing

[Standalone Version] pythondemo\roundmeter.py
#!/usr/bin/python
from pychartdir import *

# The value to display on the meter
value = 72.3

# Create an AngularMeter object of size 250 x 250 pixels with transparent background
m = AngularMeter(250, 250, Transparent)

# Center at (125, 125), scale radius = 111 pixels, scale angle -145 to +145 degrees
m.setMeter(125, 125, 111, -145, 145)

# Add a very light grey (0xeeeeee) circle with radius 123 pixels as background
m.addRing(0, 123, 0xeeeeee)
# Add a grey (0xcccccc) ring between radii 116 and 123 pixels as border
m.addRing(116, 123, 0xcccccc)

# Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units
m.setScale(0, 100, 10, 5, 1)

# Set the scale label style to 15pt Arial Italic. Set the major/minor/micro tick lengths to 12/9/6
# pixels pointing inwards, and their widths to 2/1/1 pixels.
m.setLabelStyle("ariali.ttf", 15)
m.setTickLength(-12, -9, -6)
m.setLineWidth(0, 2, 1, 1)

# Add a smooth color scale to the meter
smoothColorScale = [0, 0x3333ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100, 0xff0000]
m.addColorScale(smoothColorScale)

# Add a text label centered at (125, 175) with 15pt Arial Italic font
m.addText(125, 175, "CPU", "ariali.ttf", 15, TextColor, Center)

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

# Output the chart
m.makeChart("roundmeter.png")

[CGI Version] pythondemo_cgi\roundmeter.py
#!/usr/bin/python
from pychartdir import *

# The value to display on the meter
value = 72.3

# Create an AngularMeter object of size 250 x 250 pixels with transparent background
m = AngularMeter(250, 250, Transparent)

# Center at (125, 125), scale radius = 111 pixels, scale angle -145 to +145 degrees
m.setMeter(125, 125, 111, -145, 145)

# Add a very light grey (0xeeeeee) circle with radius 123 pixels as background
m.addRing(0, 123, 0xeeeeee)
# Add a grey (0xcccccc) ring between radii 116 and 123 pixels as border
m.addRing(116, 123, 0xcccccc)

# Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units
m.setScale(0, 100, 10, 5, 1)

# Set the scale label style to 15pt Arial Italic. Set the major/minor/micro tick lengths to 12/9/6
# pixels pointing inwards, and their widths to 2/1/1 pixels.
m.setLabelStyle("ariali.ttf", 15)
m.setTickLength(-12, -9, -6)
m.setLineWidth(0, 2, 1, 1)

# Add a smooth color scale to the meter
smoothColorScale = [0, 0x3333ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100, 0xff0000]
m.addColorScale(smoothColorScale)

# Add a text label centered at (125, 175) with 15pt Arial Italic font
m.addText(125, 175, "CPU", "ariali.ttf", 15, TextColor, Center)

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

# Output the chart
print("Content-type: image/png\n")
binaryPrint(m.makeChart2(PNG))