Statement on glibc/iconv Vulnerability

    imageopenpolygon

    (PHP 7 >= 7.2.0, PHP 8)

    imageopenpolygon — Draws an open polygon

    Descrizione

    Signature as of PHP 8.0.0 (not supported with named arguments)

    imageopenpolygon(GdImage $image, array $points, int $color): bool

    Alternative signature (deprecated as of PHP 8.1.0)

    imageopenpolygon(
        GdImage $image,
        array $points,
        int $num_points,
        int $color
    ): bool

    imageopenpolygon() draws an open polygon on the given image. Contrary to imagepolygon(), no line is drawn between the last and the first point.

    Elenco dei parametri

    image

    Una risorsa immagine, restituita da una delle funzioni di creazione immagine, come imagecreatetruecolor().

    points

    An array containing the polygon's vertices, e.g.:

    points[0] = x0
    points[1] = y0
    points[2] = x1
    points[3] = y1

    num_points

    Total number of points (vertices), which must be at least 3.

    If this parameter is omitted as per the second signature, points must have an even number of elements, and num_points is assumed to be count($points)/2.
    color

    A color identifier created with imagecolorallocate().

    Valori restituiti

    Restituisce true in caso di successo, false in caso di fallimento.

    Log delle modifiche

    Versione Descrizione
    8.1.0 The parameter num_points has been deprecated.
    8.0.0 image expects a GdImage instance now; previously, a valid gd resource was expected.

    Esempi

    Example #1 imageopenpolygon() example

    <?php
    // Create a blank image
    $image = imagecreatetruecolor(400, 300);

    // Allocate a color for the polygon
    $col_poly = imagecolorallocate($image, 255, 255, 255);

    // Draw the polygon
    imageopenpolygon($image, array(
    0, 0,
    100, 200,
    300, 200
    ),
    3,
    $col_poly);

    // Output the picture to the browser
    header('Content-type: image/png');

    imagepng($image);
    imagedestroy($image);
    ?>

    Il precedente esempio visualizzerà qualcosa simile a:

    Output of example : imageopenpolygon()

    Vedere anche:

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    User Contributed Notes 1 note

    up
    0
    marco at oostende dot nl
    5 years ago
    In case you want to use an open polygon but are stuck with a PHP version prior to 7.2, a solution may be to 'backplot' your array to its original start. Say you have an array of pixels (below seperated by commas)

    <?php
    $arr     = array();
    for (    $i = 0; $i < count($pixels); $i++) {
    $pixel = explode(',', $pixels[$i]);
    if ((    $pixel[0] > 0) && ($pixel[1] > 0)) {
    $arr[] = $pixel[0];
    $arr[] = $pixel[1];
    }
    }
    imagepolygon($im, $arr, (count($arr) / 2), $otcolor);
    ?>

    you can replace this by something like

    <?php
    $arr     = array();
    for (    $i = 0; $i < count($pixels); $i++) {
    $pixel = explode(',', $pixels[$i]);
    $arr[] = $pixel[0];
    $arr[] = $pixel[1];
    }
    // imageopenpolygon($im, $arr, (count($arr) / 2), $otcolor) is not possible, so...
    for ($i = (count($pixels)-1); $i >= 0; $i--) {
    $pixel = explode(',', $pixels[$i]);
    $arr[] = $pixel[0];
    $arr[] = $pixel[1];
    }
    imagepolygon($im, $arr, (count($arr) / 2), $otcolor);
    ?>
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