If you're looking for easy text alignment, you need to use the imagettfbbox() command. When given the correct parameters, it will return the boundaries of your to-be-made text field in an array, which will allow you to calculate the x and y coordinate that you need to use for centering or aligning your text.
A horizontal centering example:
<?php
$tb = imagettfbbox(17, 0, 'airlock.ttf', 'Hello world!');
?>
$tb would contain:
Array
(
[0] => 0 // lower left X coordinate
[1] => -1 // lower left Y coordinate
[2] => 198 // lower right X coordinate
[3] => -1 // lower right Y coordinate
[4] => 198 // upper right X coordinate
[5] => -20 // upper right Y coordinate
[6] => 0 // upper left X coordinate
[7] => -20 // upper left Y coordinate
)
For horizontal alignment, we need to substract the "text box's" width { $tb[2] or $tb[4] } from the image's width and then substract by two.
Saying you have a 200px wide image, you could do something like this:
<?php
$x = ceil((200 - $tb[2]) / 2); imagettftext($im, 17, 0, $x, $y, $tc, 'airlock.ttf', 'Hello world!'); ?>
This'll give you perfect horizontal center alignment for your text, give or take 1 pixel. Have fun!
