PHPのお勉強！

PHP TOP
PHP 8.4.2 Released!

    imagefilledpolygon

    (PHP 4, PHP 5, PHP 7, PHP 8)

    imagefilledpolygon — 塗りつぶした多角形を描画する

    説明

    PHP 8.0.0 以降のシグネチャ(名前付き引数をサポートしていません)

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

    代替のシグネチャ (PHP 8.1.0 以降 は非推奨)

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

    imagefilledpolygon() は画像 image 上に塗りつぶした多角形を生成します。

    パラメータ

    image

    imagecreatetruecolor()のような画像作成関数が返す GdImage オブジェクト。

    points

    多角形の頂点の座標 x および y を含む配列。

    num_points

    頂点の総数。 3 以上である必要があります。

    代替のシグネチャ(PHP 8.0.0 以降) でこの引数が省略された場合、 points は偶数でなければいけません。また、 num_points は count($points)/2 であると仮定されます。
    color

    imagecolorallocate() で作成された色識別子。

    戻り値

    成功した場合に true を、失敗した場合に false を返します。

    変更履歴

    バージョン 説明
    8.1.0 引数 num_points は、推奨されなくなりました。
    8.0.0 image は、 GdImage クラスのインスタンスを期待するようになりました。 これより前のバージョンでは、有効な gd resource が期待されていました。

    例

    例1 imagefilledpolygon() の例

    <?php
    // 多角形の点の配列を準備します
    $values = array(
    40, 50, // Point 1 (x, y)
    20, 240, // Point 2 (x, y)
    60, 60, // Point 3 (x, y)
    240, 20, // Point 4 (x, y)
    50, 40, // Point 5 (x, y)
    10, 10 // Point 6 (x, y)
    );

    // 画像を生成します
    $image = imagecreatetruecolor(250, 250);

    // 色を割り当てます
    $bg = imagecolorallocate($image, 0, 0, 0);
    $blue = imagecolorallocate($image, 0, 0, 255);

    // 背景を塗りつぶします
    imagefilledrectangle($image, 0, 0, 249, 249, $bg);

    // 多角形を描画します
    imagefilledpolygon($image, $values, 6, $blue);

    // 画像を出力します
    header('Content-type: image/png');
    imagepng($image);
    imagedestroy($image);
    ?>

    上の例の出力は、 たとえば以下のようになります。

    出力例 : imagefilledpolygon()

    参考

    Found A Problem?

    Learn How To Improve This Page • Submit a Pull Request • Report a Bug
    ＋add a note

    User Contributed Notes 9 notes

    up
    0
    martin at eksperimentrum dot dk
    6 years ago
    How to draw a simple 6-sided star img where x,y is center of the star and s is the size:

    function drawStar($img, $x, $y, $s, $color) {
    $x=$x-$s/2;
    $y=$y-$s/4;
    $points=array($x,$y, $x+$s/2,$y+$s, $x+$s,$y);
    imagefilledpolygon($img, $points, 3, $color);
    $points=array($x,2/3*$s+$y, $x+$s/2,$y-$s/3, $x+$s,2/3*$s+$y);
    imagefilledpolygon($img, $points, 3, $color);
    }
    up
    0
    Steween
    7 years ago
    My version of drawStar (with examples)

    <?php
    header     ("Content-type: image/png");

    /* drawStar or regular polygon
    $x, $y -> Position in the image
    $radius -> Radius of the star
    $spikes -> Number of spikes (min 2)
    $ratio -> Ratio between outer and inner points
    $dir -> Rotation 270° for having an up spike( with ratio<1)
    */
    function drawStar($x, $y, $radius, $spikes=5, $ratio=0.5, $dir=270) {
    $coordinates = array();
    $angle = 360 / $spikes ;
    for(    $i=0; $i<$spikes; $i++){
    $coordinates[] = $x + ( $radius * cos(deg2rad($dir+$angle*$i)));
    $coordinates[] = $y + ( $radius * sin(deg2rad($dir+$angle*$i)));
    $coordinates[] = $x + ($ratio*$radius * cos(deg2rad($dir+$angle*$i + $angle/2)));
    $coordinates[] = $y + ($ratio*$radius * sin(deg2rad($dir+$angle*$i + $angle/2)));
    }
    return     $coordinates ;
    }

    // 14*20+24*2 = 328 Examples
    $im = imagecreate(800,600);
    imagecolorallocate($im, 0, 0, 0);
    $w = imagecolorallocate($im, 255, 255, 255);
    $r = imagecolorallocate($im, 255, 0, 0);
    for (    $spikes=2; $spikes<16; $spikes++) { //[2-15]
    for ($ratio=1; $ratio<21; $ratio++) { //[0.1-2.0]
    $values = drawStar(40*$ratio-20, $spikes*40-60, 10, $spikes, $ratio/10);
    imagefilledpolygon($im, $values, count($values)/2, ($ratio % 5 == 0) ? $r : $w);
    }
    }
    for (    $dir=0; $dir<24; $dir++) {
    $values = drawStar(30*$dir+20, 580, 10, 2, 1.5, $dir*15);
    imagefilledpolygon($im, $values, count($values)/2, $w);
    $values = drawStar(30*$dir+20, 580, 10, 2, 0.2, $dir*15);
    imagefilledpolygon($im, $values, count($values)/2, $r);
    }
    imagepng($im);
    imagedestroy($im);
    ?>
    up
    0
    rbenheidorn at gmail dot com
    9 years ago
    Discovered while working on printing geographical boundaries to an image: if you provide floating point vertices, then the decimal value is automatically truncated. This can cause images drawn with floating point vertices to shift slightly towards the top-left corner. My personal resolution is to round all of the vertices to their nearest whole values, which eliminates this shift.
    up
    0
    austinoblouk at yahoo dot com
    15 years ago
    Actually the minimum it allows is 3. It says "Total number of vertices, which must be bigger than 3." but it allows 3...
    up
    0
    webmaster at mywebsolution dot de
    17 years ago
    Just thought that 'tatlar at yahoo dot com's function has some redundant code in it, so I tried to "improve" it. Now you can choose a variable number of spikes.

    <?php
    error_reporting    (E_ALL);
    function     drawStar($x, $y, $radius, $spikes=5) {
    // $x, $y -> Position in the image
    // $radius -> Radius of the star
    // $spikes -> Number of spikes

    $coordinates = array();
    $angel = 360 / $spikes ;

    // Get the coordinates of the outer shape of the star
    $outer_shape = array();
    for(    $i=0; $i<$spikes; $i++){
    $outer_shape[$i]['x'] = $x + ($radius * cos(deg2rad(270 - $angel*$i)));
    $outer_shape[$i]['y'] = $y + ($radius * sin(deg2rad(270 - $angel*$i)));
    }

    // Get the coordinates of the inner shape of the star
    $inner_shape = array();
    for(    $i=0; $i<$spikes; $i++){
    $inner_shape[$i]['x'] = $x + (0.5*$radius * cos(deg2rad(270-180 - $angel*$i)));
    $inner_shape[$i]['y'] = $y + (0.5*$radius * sin(deg2rad(270-180 - $angel*$i)));
    }

    // Bring the coordinates in the right order
    foreach($inner_shape as $key => $value){
    if(    $key == (floor($spikes/2)+1))
    break;
    $inner_shape[] = $value;
    unset(    $inner_shape[$key]);
    }

    // Reset the keys
    $i=0;
    foreach(    $inner_shape as $value){
    $inner_shape[$i] = $value;
    $i++;
    }

    // "Merge" outer and inner shape
    foreach($outer_shape as $key => $value){
    $coordinates[] = $outer_shape[$key]['x'];
    $coordinates[] = $outer_shape[$key]['y'];
    $coordinates[] = $inner_shape[$key]['x'];
    $coordinates[] = $inner_shape[$key]['y'];
    }

    // Return the coordinates
    return $coordinates ;
    }

    // Example
    $spikes = 5;

    $values = drawStar(250, 250, 200, $spikes);
    $im = imagecreate(500,500);
    imagecolorallocate($im,0,0,0);
    $w = imagecolorallocate($im, 255, 255, 255);
    imagefilledpolygon($im, $values, $spikes*2, $w);
    imageGIF($im);
    imagedestroy($im);
    ?>
    up
    0
    jylyn at hotmail dot com
    18 years ago
    In spite of what it says about requiring more than 3 vertices, it is possible to draw a triangle with this function!
    up
    0
    etnekor at tar dot hu
    18 years ago
    There is a simple function to draw a filled point with a chosen radius and color.

    <?php
    function drawPoint($img, $radius, $origo_x, $origo_y, $pointColor)
    {
    for (    $i=0;$i<=360;$i++)
    {
    $pont[] = $origo_x + ($radius * sin(deg2rad($i)));
    $pont[] = $origo_y - ($radius * cos(deg2rad($i)));
    }
    reset($pont);
    ImageFilledPolygon ($img, $pont, (sizeof($pont)/2), $pointColor);
    }
    ?>
    up
    -1
    tatlar at yahoo dot com
    18 years ago
    <?php function _makeFiveSidedStar( $x, $y, $radius, $shape='polygon', $spiky=NULL ) {
    // $x, $y co-ords of origin (in pixels), $radius (in pixels), $shape - 'polygon' or 'star', $spikiness - ratio between 0 and 1
    $point = array() ;
    $angle = 360 / 5 ;
    $point[0]['x'] = $x ;
    $point[0]['y'] = $y - $radius ;
    $point[2]['x'] = $x + ( $radius * cos( deg2rad( 90 - $angle ) ) ) ;
    $point[2]['y'] = $y - ( $radius * sin( deg2rad( 90 - $angle ) ) ) ;
    $point[4]['x'] = $x + ( $radius * sin( deg2rad( 180 - ( $angle*2 ) ) ) ) ;
    $point[4]['y'] = $y + ( $radius * cos( deg2rad( 180 - ( $angle*2 ) ) ) ) ;
    $point[6]['x'] = $x - ( $radius * sin( deg2rad( 180 - ( $angle*2 ) ) ) ) ;
    $point[6]['y'] = $y + ( $radius * cos( deg2rad( 180 - ( $angle*2 ) ) ) ) ;
    $point[8]['x'] = $x - ( $radius * cos( deg2rad( 90 - $angle ) ) ) ;
    $point[8]['y'] = $y - ( $radius * sin( deg2rad( 90 - $angle ) ) ) ;
    if(     $shape == 'star' ) {
    if(     $spiky == NULL ) $spiky = 0.5 ; // default to 0.5
    $indent = $radius * $spiky ;
    $point[1]['x'] = $x + ( $indent * cos( deg2rad( 90 - $angle/2 ) ) ) ;
    $point[1]['y'] = $y - ( $indent * sin( deg2rad( 90 - $angle/2 ) ) ) ;
    $point[3]['x'] = $x + ( $indent * sin( deg2rad( 180 - $angle ) ) ) ;
    $point[3]['y'] = $y - ( $indent * cos( deg2rad( 180 - $angle ) ) ) ;
    $point[5]['x'] = $x ;
    $point[5]['y'] = $y + ( $indent * sin( deg2rad( 180 - $angle ) ) ) ;
    $point[7]['x'] = $x - ( $indent * sin( deg2rad( 180 - $angle ) ) ) ;
    $point[7]['y'] = $y - ( $indent * cos( deg2rad( 180 - $angle ) ) ) ;
    $point[9]['x'] = $x - ( $indent * cos( deg2rad( 90 - $angle/2 ) ) ) ;
    $point[9]['y'] = $y - ( $indent * sin( deg2rad( 90 - $angle/2 ) ) ) ;
    }
    ksort( $point ) ;
    $coords = array() ; // new array
    foreach( $point as $pKey=>$pVal ) {
    if(     is_array( $pVal ) ) {
    foreach(     $pVal as $pSubKey=>$pSubVal ) {
    if( !empty(     $pSubVal ) ) array_push( $coords, $pSubVal ) ;
    }
    }
    }
    return     $coords ;
    }
    $values = _makeFiveSidedStar( 100, 100, 50, 'star' ) ;
    // Put values into imagepolygon function. You need to define the $image and $color, and flush it out to an image type.?>
    up
    -2
    Arnapou
    17 years ago
    I discovered that the GD imagefilledpolygon function is incorrect for some drawing with transparent color (for example red 50% : RGBA = 255, 0, 0, 64).

    I tried to draw a complex form with lots of points really near (1 pixel of distance) and a transparent red.

    The problem was : some border pixels were not drawn by the imagefilledpolygon but were drawn with imagepolygon !?!?

    So I wrote my own imagefilledpolygon function which work very well in all case I tested.

    <?php
    // $points should be an array of coordinates like that :
    $points = array(
    array(    0, 0),
    array(    100, 50),
    array(    90, 100),
    array(    50, 50),
    array(    70, 30),
    array(    10, 10),
    );
    ?>

    <?php
    function myimagefilledpolygon(& $img, $points, $color) {
    $scanline = 99999;
    // compute edges
    $all_edges = array();
    $n = count($points);
    for(    $i=0; $i<$n; $i++) {
    $p1 = $points[$i];
    if (    $i == $n-1) { $p2 = $points[0]; } else { $p2 = $points[$i+1]; }
    $x1 = $p1[0]; $y1 = $p1[1];
    $x2 = $p2[0]; $y2 = $p2[1];
    if (    $y1 != $y2) {
    $invslope = ($x2 - $x1)/($y2 - $y1);
    if (    $y1 < $y2 ) {
    $ymin = $y1;
    $xval = $x1;
    $ymax = $y2;
    } else {
    $ymin = $y2;
    $xval = $x2;
    $ymax = $y1;
    }
    $all_edges[] = array($ymin, $ymax, $xval, $invslope);
    if (    $ymin < $scanline) { $scanline = $ymin; }
    } else {
    if (    $y1 < $scanline) { $scanline = $y1; }
    if (    $y2 < $scanline) { $scanline = $y2; }
    }
    }
    // draw
    $active = array();
    do {
    // add edges to active array
    $tmp = array();
    $n = count($all_edges);
    for(    $i=0; $i<$n; $i++) {
    if (    $all_edges[$i][0] == $scanline) {
    $active[] = $all_edges[$i];
    } else {
    $tmp[] = $all_edges[$i];
    }
    }
    $all_edges = $tmp;
    // remove previous edges from active array
    $tmp = array();
    $n = count($active);
    for(    $i=0; $i<$n; $i++) {
    if (    $active[$i][1] > $scanline) {
    $tmp[] = $active[$i];
    }
    }
    $active = $tmp;
    // sort active tab
    $n = count($active);
    for(    $i=0; $i<$n-1; $i++) {
    $min = $i;
    for(    $k=$i+1; $k<$n; $k++) {
    if (    $active[$k][2] < $active[$min][2]) { $min = $k; }
    }
    if (    $i != $min) {
    $tmp = $active[$i];
    $active[$i] = $active[$min];
    $active[$min] = $tmp;
    }
    }
    // draw
    $n = count($active);
    for(    $i=0; $i<$n; $i+=2) {
    if (    $i+1 < $n) {
    if (    $tmp[$i][2] == $active[$i+1][2]) {
    imagesetpixel($img, round($active[$i][2]), $scanline, $color);
    } else {
    imageline($img, round($active[$i][2]), $scanline, round($active[$i+1][2]), $scanline, $color);
    }
    }
    }
    // increment x values
    $n = count($active);
    for(    $i=0; $i<$n; $i++) { $active[$i][2] += $active[$i][3]; }
    $scanline++;
    } while (    count($all_edges) + count($active) > 0);
    }
    ?>
    ＋add a note