Bug 307003

Summary:	Windows are sometimes blurred making fonts hardly readable
Product:	[Plasma] kwin	Reporter:	Ruslan Kabatsayev <b7.10110111>
Component:	compositing	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED NOT A BUG
Severity:	normal	CC:	headrift, masterdany88, mikiya.okuno
Priority:	NOR	Flags:	mgraesslin: NVIDIA+
Version:	4.9.0
Target Milestone:	---
Platform:	Ubuntu
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Screenshot of blur How it should look (look at yakuake)

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. ***