Pie chart generation classes and examples

Automatically generate a pie chart based on the input parameters.

/*
 * Generate pie-shaped image
 */
class PieChart {
 private $center; //Pie-shaped midpoint
 private $width; //Pie-shaped diameter
 private $image ; //Graphic object

 function __construct($width,$backcolor = array(array("r"=>0xFF,"g"=>0xFF,"b"=>0xFF))) {
 $this ->width = $width;
 $this->center = $width / 2;

 //Create a graphic object
 $this->image = imagecreatetruecolor($this->width, $this-> width);

 //Fill the initial graphic with white
 $color = imagecolorallocate($this->image, $backcolor[0]["r"], $backcolor[0]["g"], $backcolor [0]["b"]);
 imagefill($this->image, 0, 0, $color);
 }

 //Set graph data
 public function graphData($data, $colors){
 $black = imagecolorallocate($this->image, 0x00, 0x00, 0x00);

 $sum = array_sum($data);

 $start = -90;

 for($i=0; $i< count($data); $i++){
 $color = imagecolorallocate($this->image, $colors[$i]["r"], $colors[$i]["g"], $colors[ $i]["b"]);

 $stop = @($data[$i] / $sum * 360) + $start;

 imagefilledarc($this->image, $this->center , $this->center,
 $this->width, $this->width, $start, $stop, $color, IMG_ARC_PIE);
 imagefilledarc($this->image, $this-> center, $this->center,
 $this->width, $this->width, $start, $stop, $black, IMG_ARC_NOFILL | IMG_ARC_EDGED);

 $start = $stop;
 }
 }

 //Generate graphics
 public function flushImage(){
 header("Content-type:image/png");
 imagepng($this->image);
 }
}
?>

include_once 'piechart.cls.php';

$total = $_GET["total"];
$count = $_GET["count"];

$data = array ($total-$count,$count);
$colors = array(
 array('r'=>0xDD,'g'=>0xEE,'b'=>0xFF),
 array('r '=>0xFF,'g'=>0xBB,'b'=>0xAA)
);

$chart = new PieChart(200,array(array("r"=>0xF9,"g" =>0xF9,"b"=>0xF9)));
$chart->graphData($data, $colors);
$chart->flushImage();
?>