php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login

go to bug id or search bugs for

Bug #65895 ImagickDraw line opacity doesn't work
Submitted: 2013-10-14 17:14 UTC Modified: 2013-12-03 12:53 UTC
From: mail at jdborg dot com Assigned: mkoppanen (profile)
Status: Not a bug Package: imagick (PECL)
PHP Version: Irrelevant OS: CentOS 6.4
Private report: No CVE-ID: None
View Developer Edit
Welcome back! If you're the original bug submitter, here's where you can edit the bug or add additional notes.
If you forgot your password, you can retrieve your password here.
Password:
Status:
Package:
Bug Type:
Summary:
From: mail at jdborg dot com
New email:
PHP Version: OS:

 

 [2013-10-14 17:14 UTC] mail at jdborg dot com 
Description:
------------
I thought this was a legacy problem, but updated Imagick to 3.1.2 and ImageMagic to 6.8.7-0 2013-10-11 Q16.

When trying to draw a line on an image, opacity is ignored.

Test script:
---------------
$draw = new ImagickDraw();
$draw->setStrokeWidth(1);
$draw->setStrokeOpacity(0.5);
$draw->setStrokeColor(new ImagickPixel('#323232'));
$draw->line(0, 0, 10, 10);

Expected result:
----------------
A 50% opacity line is drawn.

Actual result:
--------------
A fully opaque line is drawn.

Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2013-10-15 13:16 UTC] mail at jdborg dot com 
Full test:
$draw = new ImagickDraw();
$draw->setStrokeWidth(1);
$draw->setStrokeOpacity(0.1);
$draw->setStrokeColor("black");
$draw->line(0, 0, 500, 500);

$drawing = new Imagick();
$drawing->newImage(500, 500, "red");
$drawing->setImageFormat("png");
$drawing->drawImage($draw);

header("Content-Disposition: attachment; filename=test.png");
echo $drawing->getImageBlob();

The line should be barely visible.
 [2013-10-19 15:14 UTC] Danack at basereality dot com 
This is not a bug. There are two issues with your code

i) You also need to set the fill color for a line stroke, not just the stroke color. Lines are drawn with a fill width of 1 pixel.

ii) Setting the color overwrites the opacity, as the color 'black' has it's opacity set to fully opaque. Switching the order of the commands, stops the opacity being changed by the set color command.

i.e. the setStrokeOpacity modifies the strokes colour. It does not get batched up and modify the draw command.
 [2013-12-03 11:28 UTC] mike@php.net
-Assigned To: +Assigned To: mkoppanen
 [2013-12-03 12:53 UTC] mkoppanen@php.net
-Status: Assigned +Status: Not a bug
 [2013-12-03 12:53 UTC] mkoppanen@php.net 
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to report
a bug at http://bugs.php.net/how-to-report.php
 
PHP Copyright © 2001-2025 The PHP Group
All rights reserved. 		Last updated: Mon Jul 07 10:01:34 2025 UTC