php - 使用 gd 在图像边界内换行文本

Question

我正在尝试将文本从数据库写入图像。文本有时包含很长的行，因此它无法在图像上显示为一行。

截至目前，我得到的输出为:http://prntscr.com/29l582

这是为此的代码:

$imageCreator = imagecreatefrompng($i+1 . ".png");
        $textColor = imagecolorallocate($imageCreator, 0, 0, 0);
        $textfromdb = $factformatted['fact'];
        $y = imagesy($imageCreator) - 228;
        $dimensions = imagettfbbox(20, 0, $fontname, $textfromdb);
        $x = ceil(($imageWidth - $dimensions[4]) / 2);
        imagettftext($imageCreator, 20, 0, $x, $y, $textColor, $fontname, $textfromdb);
        imagepng($imageCreator, "./fact".$i.".png");

有人可以帮我让它工作吗？

Answer 1

您可以使用 wordwrap函数和 explode函数截断多个字符串数组中的文本，然后打印它们:

$word = explode("\n", wordwrap ( "A funny string that I want to wrap", 10));

您获得此输出:

 array(5) {
  [0]=>
  string(7) "A funny"
  [1]=>
  string(6) "string"
  [2]=>
  string(6) "that I"
  [3]=>
  string(7) "want to"
  [4]=>
  string(4) "wrap"
}

你可以详细说明它(剪切文本，在不同的行上打印每个字符串，等等)。

示例(换行打印):

...
$dimensions = imagettfbbox(20, 0, $fontname, $textfromdb);
$y = imagesy($imageCreator) - 228;
$text = explode("\n", wordwrap($textfromdb, 20)); // <-- you can change this number
$delta_y = 0;
foreach($text as $line) {
    $delta_y =  $delta_y + $dimensions[3];
    imagettftext($imageCreator, 20, 0, 0, $y + $delta_y, $textColor, $fontname, $line);
}
...

垂直和水平居中:

...
$dimensions = imagettfbbox(20, 0, $fontname, $textfromdb);
$margin = 10;
$text = explode("\n", wordwrap($textfromdb, 20)); // <-- you can change this number
$delta_y = 0;
//Centering y
$y = (imagesy($imageCreator) - (($dimensions[1] - $dimensions[7]) + $margin)*count($text)) / 2;

foreach($text as $line) {
    $dimensions = imagettfbbox(20, 0, $fontname, $line);
    $delta_y =  $delta_y + ($dimensions[1] - $dimensions[7]) + $margin;
    //centering x:
    $x = imagesx($imageCreator) / 2 - ($dimensions[4] - $dimensions[6]) / 2;

    imagettftext($imageCreator, 20, 0, $x, $y + $delta_y, $textColor, $fontname, $line);
}
...