sk89q

Here’s a PHP code snippet that draws text bounded by a textbox using the GD library. It supports rotation, vertical and horizontal alignments, configurable line heights and leading, word wrap (obviously), character wrap, and text outlines. While this frankly belongs in a class (or a namespace) due its size, it’s in a function. You’re free to trim away unneeded functionality.

However, be aware that:

• You should specify a line height, or text won’t appear consistently spaced with different source texts.
• The alignment isn’t exactly pixel-perfect yet.
• The function is best used for languages that have a space character.
• To be honest, the code has some pretty bad alignment issues. It may or may not matter in your case. I would like to rewrite this from scratch, but that takes some time.

You can find the code snippet here:
http://sk89q.therisenrealm.com/pastebin/php/imagettftextboxopt.phps

Example usage:

$size = 14;
$angle = 34;
$left = 10;
$top = 40;
$color = imagecolorallocate($im, 255, 0, 0);
$fontfile = "arial.ttf";
$text = "Test";
$opt = array(
    'width' => 300,
    'line_height' => 15,
    'orientation' => array(ORIENTATION_TOP, ORIENTATION_LEFT),
    'align' => ALIGN_LEFT,
    'v_align' => VALIGN_TOP,
    'outlines' = array(
        array(5, imagecolorallocate($im, 0, 255, 0)),
        array(2, imagecolorallocate($im, 0, 0, 255)),
    ),
    // More options documented in the code
);
imagettftextboxopt($im, $size, $angle, $left, $top, $color, $fontfile, $text, $opt);

Maybe in the future, I’ll implement this as a class, fix the small bugs, and allow for textbox overflow.

Ideally, you should use ImageMagick. It does this better and faster than any native PHP code can. It is also a better image manipulation library. Even if I were to fix up this code, it is not possible for me to handle particular font features such as kernings.

This entry was posted on Friday, August 1st, 2008 at 12:53 am and is filed under Code, PHP. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.