Bug 307003 - Windows are sometimes blurred making fonts hardly readable
Summary: Windows are sometimes blurred making fonts hardly readable
Status: RESOLVED NOT A BUG
Alias: None
Product: kwin
Classification: Plasma
Component: compositing (show other bugs)
Version: 4.9.0
Platform: Ubuntu Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
: 308620 311698 327443 (view as bug list)
Depends on:
Blocks:
 
Reported: 2012-09-18 21:03 UTC by Ruslan Kabatsayev
Modified: 2013-11-11 14:05 UTC (History)
3 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:
mgraesslin: NVIDIA+

Attachments
Screenshot of blur (503.93 KB, image/png)
2012-09-18 21:06 UTC, Ruslan Kabatsayev 		Details
How it should look (look at yakuake) (455.66 KB, image/png)
2012-09-18 21:06 UTC, Ruslan Kabatsayev 		Details
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Description Ruslan Kabatsayev 2012-09-18 21:03:35 UTC 
In some circumstances windows become blurred a bit, this is especially noticeable on text content. This happens even when Blur effect is disabled.
The blurred region is not always the whole screen: sometimes some rectangular regions are excluded from blurring.

Reproducible: Always

Steps to Reproduce:
1. Open some window, e.g. System Settings
2. Eject Yakuake window
3. Open Kickoff menu
Actual Results:  
Yakuake text becomes blurred

Expected Results:  
Nothing should get blurred
Comment 1 Ruslan Kabatsayev 2012-09-18 21:06:19 UTC 
Created attachment 74010 [details]
Screenshot of blur

Here's how it looks.
I'm using nvidia binary driver 304.43 on GeForce GTX460.
Comment 2 Ruslan Kabatsayev 2012-09-18 21:06:48 UTC 
Created attachment 74011 [details]
How it should look (look at yakuake)
Comment 3 Ruslan Kabatsayev 2012-09-18 21:08:58 UTC 
This doesn't happen when I set compositing to XRender.
Comment 4 Thomas Lübking 2012-09-18 21:14:02 UTC 
does it happen if you disable "OpenGL 2 shaders"?
Comment 5 Ruslan Kabatsayev 2012-09-18 21:16:47 UTC 
Yes, it still happens.
My wild guess is that it might be related to wrong mipmap level used when updating image, but I'm not sure whether it'd be in driver or in kwin.
Comment 6 Thomas Lübking 2012-09-18 21:19:49 UTC 
There should no longer be any mipmapping in use.
Did you activate the fxaa setting (or other FSAA overrides) in nvidia-settings or change the image to high performance?
Comment 7 Ruslan Kabatsayev 2012-09-18 21:22:28 UTC 
Disabled FXAA, moved slider to high quality, issue still present.
Comment 8 Ruslan Kabatsayev 2012-09-18 21:25:22 UTC 
Oh, just tried restarting Kwin so that FXAA toggle could take effect, and the bug doesn't appear. So I guess I shouldn't have it enabled for all apps.
Comment 9 Ruslan Kabatsayev 2012-09-18 21:31:08 UTC 
Thanks for your help. I'm closing this as INVALID since kwin doesn't seem to be able to cope with forcing FXAA.
Comment 10 Thomas Lübking 2012-09-18 21:39:22 UTC 
(In reply to comment #9)
> Thanks for your help. I'm closing this as INVALID since kwin doesn't seem to
> be able to cope with forcing FXAA.

You rather don't want texture antialiasing in your desktop - unfortunately there's afaik (so far) no environment variable to control FXAA, you'd have to use nvidia-settings -a fxaa 1; run game & nvidia-settings -a fxaa 0 (or 0/1 it around kwin)
Comment 11 Ruslan Kabatsayev 2012-09-18 21:41:33 UTC 
Yeah, that's how I used to do this on another machine for other reasons.
And by kwin coping with FXAA I meant its ability to disable FXAA.
Comment 12 Thomas Lübking 2012-09-18 22:06:11 UTC 
would you know "how" - it seems much a driver feature and just overrides all GL_MULTISAMPLE calls
Unless there's an enviroment var to deactivate it for the process, i would not know how to convince the driver to skip it.
Comment 13 Ross Burton 2012-10-19 13:46:12 UTC 
*** Bug 308620 has been marked as a duplicate of this bug. ***
Comment 14 Thomas Lübking 2012-12-14 16:28:35 UTC 
*** Bug 311698 has been marked as a duplicate of this bug. ***
Comment 15 Thomas Lübking 2013-11-11 14:05:35 UTC 
*** Bug 327443 has been marked as a duplicate of this bug. ***