| Bug #39366 | imagerotate preserve alpha channel only if degree less then 45 | ||||
|---|---|---|---|---|---|
| Submitted: | 3 Nov 2006 10:16pm UTC | Modified: | 4 Nov 2006 3:24am UTC | ||
| From: | ciakana at gmail dot com | Assigned to: | pajoye | ||
| Status: | Closed | Category: | GD related | ||
| Version: | 5.2.0 | OS: | Windows XP | ||
[3 Nov 2006 10:18pm UTC] ciakana at gmail dot com
Description:
------------
If I run the allegated script, where shade.png is a png image with a
transparent background (full alpha channel), all works if the degrees
are less then 45. If I set the degrees to 300, for example, the
background become black.
Reproduce code:
---------------
<?php
$filename="shade.png";
$degrees =300;
header('Content-type: image/png');
$source = imagecreatefrompng($filename);
$rotate = imagerotate($source, $degrees, -1);
imagealphablending($rotate, true);
imagesavealpha($rotate, true);
imagepng($rotate);
?>
Expected result:
----------------
A rotated copy of the original image with the alpha channel preserved
Actual result:
--------------
An image with a black bakground
[4 Nov 2006 3:24am UTC] pajoye@php.net
This bug has been fixed in CVS. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. Thank you for the report, and for helping us make PHP better.
Description: ------------ If I run the allegated script, where shade.png is a png image with a transparent background (full alpha channel), all works if the degrees are less then 45. If I set the degrees to 300, for example, the background become black. Reproduce code: --------------- <?php $filename="shade.png"; $degrees =300; header('Content-type: image/png'); $source = imagecreatefrompng($filename); $rotate = imagerotate($source, $degrees, -1); imagealphablending($rotate, true); imagesavealpha($rotate, true); imagepng($rotate); ?> Expected result: ---------------- An image with a black bakground Actual result: -------------- A rotated copy of the original image with the alpha channel preserved