Edit report at https://bugs.php.net/bug.php?id=55545&edit=1
ID: 55545
Comment by: phpbugs at exaseb dot de
Reported by: phpbugs at exaseb dot de
Summary: imagettftext() antialiasing depends on color
allocation order
Status: Open
Type: Bug
Package: GD related
Operating System: Windows XP, 32bit
PHP Version: 5.3.8
Block user comment: N
Private report: N
New Comment:
I compared this problem with #21554, #7769, #18455 and #15405 and think that it
is slightly different so I opened a new issue.
Previous Comments:
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[2011-08-31 03:27:57] phpbugs at exaseb dot de
Description:
------------
GD version: bundled (2.0.34 compatible)
Using a negative $color parameter for imagettftext() does not produce
antialiased text if the image is created with imagecreate() (as opposed to
imagecreatetruecolor()) and the text color is the first color allocated.
I have not looked into this but I suppose the first color recieves an index of
0, thus a test for <0 always fails and antialiasing is never used. Using a
negative color index is a really awful hack. imagettftext() should receive an
additional parameter instead.
Test script:
---------------
<?php
$im = imagecreate(210, 50);
$background_color = imagecolorallocate($im, 0, 0, 0);
$text_color = imagecolorallocate($im, 255, 255, 255);
imagefilledrectangle($im, 0, 0, 209, 49, $background_color);
imagettftext($im, 20, 0, 10, 20, -$text_color, "arial.ttf", "Antialiasing");
imagetruecolortopalette($im, FALSE, 255);
imagepng($im, "as_intended.png");
imagedestroy($im);
$im = imagecreate(210, 50);
$text_color = imagecolorallocate($im, 255, 255, 255);
$background_color = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 209, 49, $background_color);
imagettftext($im, 20, 0, 10, 20, -$text_color, "arial.ttf", "Antialiasing");
imagetruecolortopalette($im, FALSE, 255);
imagepng($im, "not_as_intended.png");
imagedestroy($im);
?>
Expected result:
----------------
The script should produce two identical PNG images with not antialiased text.
Actual result:
--------------
The image as_intended.png shows the expected result whereas not_as_intended.png
shows antialiased text where the text should not be antialiased.
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Edit this bug report at https://bugs.php.net/bug.php?id=55545&edit=1