PHP code example for drawing pie chart

//Variable definition, the angle size when drawing an elliptical arc
define("ANGLELENGTH",3);
/**
* Draw the picture
* @param $title The title of the 3D picture
* @param $dataArr The displayed data array
* @param $labelArr The label classification array corresponding to the data
* @param $colorArr The array corresponding to the drawing color
* @ param $a The base width of the canvas
* @param $b The base height of the canvas
* @param $v The height of the 3D column
* @param $font The font size
* @return The image access path for successful drawing
*/
function drawPieImg($title, $dataArr , $labelArr, $colorArr, $a=250, $b=120, $v=20, $font=10){
$ox = 5+$a;
$oy = 5+$b;
$fw = imagefontwidth($font);
$fh = imagefontheight($font);
$n = count($dataArr);//Calculate the array length
$w = 10+$a*2;
$h = 10+$b *2+$v+($fh+2)*$n;
//Create artboard
$img = imagecreate($w, $h);
//Convert RGB to index color
for($i=0; $ i<$n; $i++)
$colorArr[$i] = drawIndexColor($img,$colorArr[$i]);//Assign color to image $img
$clrbk = imagecolorallocate($img, 0xff, 0xff, 0xff);
$clrt = imagecolorallocate($img, 0x00, 0x00, 0x00);
//Fill the background color
imagefill($img, 0, 0, $clrbk);
//Sum
$tot = 0;
for($i=0; $i<$n; $i++)
$tot += $dataArr[$i];
//The starting angle size of each category
$sd = 0;
//Every The angle occupied by each category
$ed = 0;
$ly = 10+$b*2+$v;
for($i=0; $i<$n; $i++){
$sd = $ ed;
$ed += $dataArr[$i]/$tot*360;
//Draw 3D sector
draw3DSector($img, $ox, $oy+20, $a, $b, $v, $sd , $ed, $colorArr[$i]);
//Draw label
imagefilledrectangle($img, 5, $ly, 5+$fw, $ly+$fh, $colorArr[$i]);
imagerectangle($ img, 5, $ly, 5+$fw, $ly+$fh, $clrt);
//Chinese transcoding
$str = iconv("GB2312", "UTF-8", $labelArr[$i]) ;
imagettftext($img, $font, 0, 5+2*$fw, $ly+13, $clrt, "D:/wamp/www/source/font/simhei.ttf", $str.":" .$dataArr[$i]."(".(round(10000*($dataArr[$i]/$tot))/100)."%)");
$ly += $fh+2;
 }
//Draw the picture title
imagettftext($img, 15, 0, 5, 15, $clrt, "D:/wamp/www/source/font/simhei.ttf", iconv("GB2312", "UTF- 8",$title));
//Output graphics
header("Content-type: image/png");
//Output the generated image
$imgFileName = "./".time().".png ";
imagepng($img,$imgFileName);
return $imgFileName;
}
/**
* Draw 3d sector
*/
function draw3DSector($img, $ox, $oy, $a, $b, $v, $sd, $ed, $clr) {
drawSector($img, $ox, $oy, $a, $b, $sd, $ed, $clr);
if($sd<180){
list( $red, $green, $blue) = drawDarkColor($img, $clr);
//Assign color to the image
$clr=imagecolorallocate($img, $red, $green, $blue);
if($ed> ;180)
$ed = 180;
list($sx, $sy) = getExy($a,$b,$sd);
$sx += $ox;
$sy += $oy;
list( $ex, $ey) = getExy($a, $b, $ed);
$ex += $ox;
$ey += $oy;
imageline($img, $sx, $sy, $sx, $sy+$v, $clr);
imageline($img, $ex, $ey, $ex, $ey+$v, $clr);
drawArc($img, $ox, $oy+$v, $a, $b, $sd, $ed, $clr);
list($sx, $sy) = getExy($a, $b, ($sd+$ed)/2);
$sy += $oy+$v /2;
$sx += $ox;
imagefill($img, $sx, $sy, $clr);
}
}
/**
* Draw elliptical arc
*/
function drawArc($img,$ox, $oy,$a,$b,$sd,$ed,$clr){
$n = ANGLELENGTH >0 ? ceil(($ed-$sd)/ANGLELENGTH) : -1;
$d = $sd ;
list($x0,$y0) = getExy($a,$b,$d);
for($i=0; $i<$n; $i++){
$d = ($d+ANGLELENGTH )>$ed?$ed:($d+ANGLELENGTH);
list($x, $y) = getExy($a, $b, $d);
imageline($img, $x0+$ox, $ y0+$oy, $x+$ox, $y+$oy, $clr);
$x0 = $x;
$y0 = $y;
}
}
/**
* Draw a fan
*/
function drawSector($ img, $ox, $oy, $a, $b, $sd, $ed, $clr) {
$n = ANGLELENGTH > 0 ? ceil(($ed-$sd)/ANGLELENGTH) : -1;
 $d = $sd;
list($x0,$y0) = getExy($a, $b, $d);
imageline($img, $x0+$ox, $y0+$oy, $ox, $oy, $clr);
for($i=0; $i<$n; $i++) {
$d = ($d+ANGLELENGTH)>$ed?$ed:($d+ANGLELENGTH);
list( $x, $y) = getExy($a, $b, $d);
imageline($img, $x0+$ox, $y0+$oy, $x+$ox, $y+$oy, $clr);
 $x0 = $x;
$y0 = $y;
}
imageline($img, $x0+$ox, $y0+$oy, $ox, $oy, $clr);
list($x, $y) = getExy($a/2, $b/2, ($d+$sd)/2);
imagefill($img, $x+$ox, $y+$oy, $clr);
}
/**
* Get the shadow color of the corresponding column based on $clr color
* @param $img image
* @param $clr color
* @return rgb color array
*/
function drawDarkColor($img,$clr){
$rgb = imagecolorsforindex($img,$clr);
return array($rgb["red"]/2,$rgb["green"]/ 2,$rgb["blue"]/2);
}
/**
* Find the coordinates of the point on the ellipse corresponding to angle $d
*
* @param $a Abscissa coordinate
* @param $b Vertical coordinate
* @param $d Angle
* @return Corresponding ellipse point coordinate
*/
function getExy($a, $b, $d){
$d = deg2rad($d);
return array(round($a*cos($d)), round($b*sin($d)));
}
/**
* Assign RGB indexed color to image
*/
function drawIndexColor($img, $clr){
$red = ($clr>>16) & 0xff;
$green = ($clr>>8)& 0xff;
$blue = ($clr) & 0xff;
return imagecolorallocate($img, $red, $green, $blue);
}
//Test example
$title = "Zoo Animal Type Distribution";
$dataArr = array(20, 10, 20, 20, 10, 20, 30, 10); //Test data array
$labelArr = array("elephant", "giraffe", "crocodile", "ostrich", "tiger" ", "Lion", "Monkey", "Zebra"); //Tag
$colorArr = array(0x99ff00, 0xff6666, 0x0099ff, 0xff99ff, 0xffff99, 0x99ffff, 0xff3333, 0x009999); //Corresponding color array
$result = drawPieImg($title, $dataArr,$labelArr,$colorArr);
echo "";
?>

Code description: The drawPieImg() function contains 8 parameters. $title is the title of the pie chart; $dataArr is the data array that needs to be displayed; $labelArr is the label classification array of the corresponding data; $colorArr is the drawing color array of the corresponding data. These 4 Parameters are required, just pass the corresponding parameters for different system applications.

The remaining 4 parameters are responsible for setting the size of the pie chart to be generated. If not set, the system default value will be used. The program starts drawing from 0 degrees according to the size of the array data at the bottom of the bed, and draws the sector size occupied by the corresponding data in a clockwise direction.

For those who are interested, please try the above code and see how the pie chart looks like? !