Start Angle and Direction

This example demonstrates different sector layout angles and directions.

By default, ChartDirector positions sectors starting from the upward pointing position, and in clockwise direction.

The start angle and layout direction can be changed using PieChart.setStartAngle.

One common application for PieChart.setStartAngle is to facilitate layout of pie charts containing many small sectors. Please refer to Side Label Layout for an example.

[File: phpdemo/anglepie.php]

<?php
require_once("../lib/phpchartdir.php");

# Determine the starting angle and direction based on input parameter
$angle = 0;
$clockwise = true;
if ($_REQUEST["img"] != "0") {
    $angle = 90;
    $clockwise = false;
}

# The data for the pie chart
$data = array(25, 18, 15, 12, 8, 30, 35);

# The labels for the pie chart
$labels = array("Labor", "Licenses", "Taxes", "Legal", "Insurance", "Facilities",
    "Production");

# Create a PieChart object of size 280 x 240 pixels
$c = new PieChart(280, 240);

# Set the center of the pie at (140, 130) and the radius to 80 pixels
$c->setPieSize(140, 130, 80);

# Add a title to the pie to show the start angle and direction
if ($clockwise) {
    $c->addTitle("Start Angle = $angle degrees\nDirection = Clockwise");
} else {
    $c->addTitle("Start Angle = $angle degrees\nDirection = AntiClockwise");
}

# Set the pie start angle and direction
$c->setStartAngle($angle, $clockwise);

# Draw the pie in 3D
$c->set3D();

# Set the pie data and the pie labels
$c->setData($data, $labels);

# Explode the 1st sector (index = 0)
$c->setExplode(0);

# Output the chart
header("Content-type: image/png");
print($c->makeChart2(PNG));
?>