Edit report at https://bugs.php.net/bug.php?id=65837&edit=1

 ID:                 65837
 Updated by:         fel...@php.net
 Reported by:        c dot madmax at gmail dot com
 Summary:            imageTTFText text shifted right
-Status:             Open
+Status:             Assigned
 Type:               Bug
 Package:            GD related
 Operating System:   Ubuntu 12.04
 PHP Version:        Irrelevant
-Assigned To:        
+Assigned To:        tabe
 Block user comment: N
 Private report:     N



Previous Comments:
------------------------------------------------------------------------
[2013-10-05 10:39:42] c dot madmax at gmail dot com

Description:
------------
Hello PHP Developers,

I want to inform you about a imageTTFText() bug that exists since four years. 
The problem is that imageTTFText text is shifted right. The bug is only visible 
when using a large fontsize. The bigger the font the larger the shift.

The bug was introduced with PHP 5.2.10 and reported here: 
http://bugs.php.net/bug.php?id=49600 As you can see in the history of bug 
49600, a fix was made in revision 293268 and the bug was closed. But then the 
fix was reverted in revision 296693 and obviously no one has noticed that.

I strongly urge you to fix this problem. I am using PHP 5.4.0 on Ubuntu 12.04. 
I am sure the bug still exists in all php versions >=5.2.10 until this day 
(except revision 293268-296693).

I have made a test script and uploaded a sample image on two image hosters to 
illustrate how massive the shift is:

http://img407.imageshack.us/img407/1888/mbxe.png (best quality)
http://img223.imagevenue.com/img.php?image=61219_imagettftext_shifted_122_1017lo.jpg

As you can see on the image, the character 'C' is NOT left aligned as it should 
because the x position is zero. The character is shifted approximately 20 
pixels instead and overlap the polygon (which is properly left-aligned). Some 
characters like 'A' or 'V' are only a little bit shifted, but also overlap the 
polygon. It does not matter what font you use, all are right shifted.

Note:
The array that is returned from imagettfbbox produces values that differ 1 
pixel from the values returned from imageTTFText (when using x=0; y=0) which is 
also a bug.

Please use my test script and verify the problem. If a php developper whould 
use this test script each time he made a change in imageTTFText, then such bugs 
would not occour. It seems the developer do not have enough carefulness. That's 
a point you should think about.

Test script:
---------------
<?php

$im = imagecreatetruecolor(500, 500);

$bgcolor = imagecolortransparent($im, imagecolorallocate($im, 255, 255, 255));
$fgcolor = imagecolorallocatealpha($im, 0, 0, 255, 64);

imagefill($im, 0, 0, $bgcolor);

$polygon = imagettftext(
        $im,
        480,    // size
        0,              // angle
        0,              // x
        480,    // y
        $fgcolor,
        '/usr/share/fonts/truetype/msttcorefonts/verdana.ttf',
        'C'             // text
);

imagesetthickness($im, 2);

imagepolygon(
        $im,
        $polygon,
        sizeof($polygon) / 2,
        imagecolorallocatealpha($im, 255, 0, 0, 64)
);

header('Content-Type: image/png');

imagepng($im);

exit;

?>

Expected result:
----------------
The polygon should enclose the character 'C' without overlapping the character.

Actual result:
--------------
The polygon overlap the character 'C' because every character is shifted right.


------------------------------------------------------------------------



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