Bug 270957

Summary:	Blank screensaver becomes transparent after dismissing password prompt
Product:	[Unmaintained] kscreensaver	Reporter:	Danny Baumann <dannybaumann>
Component:	general	Assignee:	kscreensaver bugs tracking <kscreensaver-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	normal	CC:	kwin-bugs-null
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	Fedora RPMs
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Danny Baumann 2011-04-14 16:03:52 UTC

Version:           unspecified (using KDE 4.6.1) 
OS:                Linux

As per the summary, the blank screensaver sometimes becomes largely transparent when dismissing the password prompt window (by pressing 'Escape'). There are some leftover black rectangles, but most parts of the desktop are visible in that state.

Reproducible: Sometimes

Steps to Reproduce:
- Enable the 'blank screen' screensaver
- Let screensaver kick in
- Move mouse to make the password prompt appear
- Dismiss password prompt by pressing 'Escape'

Actual Results:  
Screensaver becomes largely transparent

Expected Results:  
Screensaver should remain blank

I am using compiz 0.8.8, but there are people in #kde-devel who say that the same problem happens under kwin as well. I've verified that the screensaver window stays on the top of the stack, so I'm not sure what the WM could do incorrectly here, anyway.

Comment 1 Danny Baumann 2011-04-14 16:05:28 UTC

Kwin users on IRC report that the issue disappears when suspending compositing. May kscreensaver use an ARGB window with incorrectly filled alpha channel?

Comment 2 Oswald Buddenhagen 2011-05-15 14:37:13 UTC

the relevant code is

	QPalette palette;
	palette.setColor( backgroundRole(), QColor(Qt::black) );
	setPalette(palette);
	setAutoFillBackground(true);
	show();

i would expect qt to do the right thing with rgba visuals here.

maybe this is a kwin(-triggered driver) bug?

Comment 3 Thomas Lübking 2011-05-15 22:32:52 UTC

Are you using the oxygen-transparent style or the corresponding features of Bespin/QtCurve?
Are you using sth. like cairo-dock? Esp. check whether there's a custom color table on the root "xprop -root | grep COLOR"
Are you using some driver feature (eg. of the nvidia driver) to override FSAA?

Comment 4 Danny Baumann 2011-05-16 09:57:11 UTC

(In reply to comment #3)
> Are you using the oxygen-transparent style or the corresponding features of
> Bespin/QtCurve?

No.

> Are you using sth. like cairo-dock? Esp. check whether there's a custom color
> table on the root "xprop -root | grep COLOR"

No cairo-dock, no custom color table (xprop -root | grep COLOR yields no output).

> Are you using some driver feature (eg. of the nvidia driver) to override FSAA?

No.I'm using the Nvidia binary driver, but without any FSAA override.

Comment 5 Oswald Buddenhagen 2011-06-02 16:32:20 UTC


*** This bug has been marked as a duplicate of bug 246623 ***