<?

function piechart($title, $slice, $itemName, $fsizes = 0)
{

    function matchset($xx)
    {
        $arrx = array_values($xx);
        $i = 0;
        while (list ($key, $val) = each($arrx)) {
            $xy[$i] = $val;
            $i++;
        }
        $cnt = $i;
        return $xy;
    }

    $sliced = matchset($slice);
    $countqw = count($sliced);

    $ItemNames = matchset($itemName);

    // initialize some variables
    $sum = 0;
    $degrees = Array();
    $diameter = 250;
    $radius = $diameter / 2;

    // calculate sum of slices
    for ($x = 0; $x < $countqw; $x++) {
        $sum += $sliced[$x];
    }

    // convert each slice into corresponding percentage of 360-degree circle
    $degCount = 0;
    for ($y = 0; $y < $countqw; $y++) {
        if ((($sliced[$y] / $sum) * 360) > '0') {
            $degrees[$degCount] = ($sliced[$y] / $sum) * 360;
            $degCount++;
        }
    }


    // set up image and colours
    Header("Content-Type: image/png");
    $im = ImageCreate(550, 300);

    $black = ImageColorAllocateAlpha($im, 0, 0, 0, 0);
    $white = ImageColorAllocateAlpha($im, 255, 255, 255, 127);
    $hexCode = array("255,153,0", "0,204,153", "204,255,102", "255,102,102", "102,204,255", "204,153,255", "255,0,0", "51,0,255", "255,51,153", "204,0,255", "255,255,51", "51,255,51", "255,102,0");
    // fill image with white
    ImageFill($im, 0, 0, $white);

    // draw baseline
    ImageLine($im, 150, 150, 225, 150, $black);

    for ($z = 0; $z < $countqw; $z++) {
        // calculate and draw arc corresponding to each slice
        ImageArc($im, 150, 150, $diameter, $diameter, $last_angle,
            ($last_angle + $degrees[$z]), $black);
        $last_angle = $last_angle + $degrees[$z];

        // calculate coordinate of end-point of each arc by obtaining
        // length of segment and adding radius
        // remember that cos() and sin() return value in radians
        // and have to be converted back to degrees!
        $end_x = round(150 + ($radius * cos($last_angle * pi() / 180)));
        $end_y = round(150 + ($radius * sin($last_angle * pi() / 180)));

        // demarcate slice with another line
        ImageLine($im, 150, 150, $end_x, $end_y, $black);
    }

    // this section is meant to calculate the mid-point of each slice
    // so that it can be filled with colour

    // initialize some variables
    $prev_angle = 0;
    $pointer = 0;

    for ($z = 0; $z < $countqw; $z++) {
        // to calculate mid-point of a slice, the procedure is to use an angle
        //bisector
        // and then obtain the mid-point of that bisector
        $pointer = $prev_angle + $degrees[$z];
        $this_angle = ($prev_angle + $pointer) / 2;
        $prev_angle = $pointer;

        // get end-point of angle bisector
        $end_x = round(150 + ($radius * cos($this_angle * pi() / 180)));
        $end_y = round(150 + ($radius * sin($this_angle * pi() / 180)));

        // given start point (150,150) and end-point above, mid-point can be
        // calculated with standard mid-point formula
        $mid_x = round((150 + ($end_x)) / 2);
        $mid_y = round((150 + ($end_y)) / 2);

        // depending on which slice, fill with appropriate colour
        $hexCodeSplit = explode(',', $hexCode[$z]);
        $WedgeColor = ImageColorAllocate($im, $hexCodeSplit[0], $hexCodeSplit[1], $hexCodeSplit[2]);

        ImageFillToBorder($im, $mid_x, $mid_y, $black, $WedgeColor);
    }

    // write string
    ImageString($im, 5, 250, 10, "$title", $black);

    $red = ImageColorAllocate($im, 255, 153, 153);
    $blue = ImageColorAllocate($im, 0, 0, 255);

    // Create Color key and slice description
    $adjPosition = 40;

    for ($z = 0; $z < $degCount; $z++) {
        $percent = ($degrees[$z] / 360) * 100;
        $percent = round($percent, 2);
        $adjPosition = $adjPosition + 15;
        $hexCodeSplit = explode(',', $hexCode[$z]);
        $percentLen = strlen($percent);
        if ($percentLen == '4') {
            $percent = " " . "$percent";
        }
        if ($percentLen == '3') {
            $percent = "  " . "$percent";
        }
        if ($percentLen == '2') {
            $percent = "   " . "$percent";
        }
        if ($percentLen == '1') {
            $percent = "    " . "$percent";
        }
        ImageString($im, 2, 300, ($adjPosition + 1), "$percent%", $black);

        $WedgeColor = ImageColorAllocate($im, $hexCodeSplit[0], $hexCodeSplit[1], $hexCodeSplit[2]);

        ImageFilledRectangle($im, 340, $adjPosition, 350, ($adjPosition + 10), $black);
        ImageFilledRectangle($im, 341, ($adjPosition + 1), 349, ($adjPosition + 9), $WedgeColor);
        if ($fsizes) {
            if ($sliced[$z] >= "1000" && $sliced[$z] < "1000000") {
                $sliced[$z] = $sliced[$z] / 1000;
                $sliced[$z] = sprintf("%01.2f", "$sliced[$z]") . "G";
            } else
                $sliced[$z] = "$sliced[$z]" . "M";
        }
        $sliceLen = strlen($sliced[$z]);
        if ($sliceLen == '5') {
            $sliced[$z] = " " . "$sliced[$z]";
        }
        if ($sliceLen == '4') {
            $sliced[$z] = "  " . "$sliced[$z]";
        }
        if ($sliceLen == '3') {
            $sliced[$z] = "   " . "$sliced[$z]";
        }
        if ($sliceLen == '2') {
            $sliced[$z] = "    " . "$sliced[$z]";
        }
        if ($sliceLen == '1') {
            $sliced[$z] = "     " . "$sliced[$z]";
        }

        ImageString($im, 2, 360, ($adjPosition + 1), "$sliced[$z]", $black);
        ImageString($im, 2, 410, ($adjPosition + 1), "$ItemNames[$z]", $black);
    }

    // output to browser
    ImagePNG($im);
}

?>