Bug 223575

Summary:	kwin should cross fade the screen with the screensaver
Product:	[Plasma] kwin	Reporter:	Davide Bettio <davide.bettio>
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	wishlist	CC:	alessandro.ufms, brainstorm, ossi, quantumphazor
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Compiled Sources
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Davide Bettio 2010-01-20 14:16:16 UTC

Version:            (using Devel)
OS:                Linux
Installed from:    Compiled sources

When the screensaver is going to be displayed kwin should start to cross fade from the screen to the screensaver slowly. Showing suddenly the screensaver is just an anoying behaviour.
A similar effect (but faster) might be added also when the screensaver is going to be closed.

Comment 1 Andrew M 2010-11-29 07:02:47 UTC

The .xscreensaver config file has variables for fade (bool), unfade (bool), fadeSeconds (int) and fadeTicks (int) that are not obeyed by KDE screensaver.

I think that KWin can handle this (as per the title) when compositing is on to let windows with changing contents remain visible through the duration, but fall back to kscreensaver implementing a screenshot and dimming that static image when compositing is disabled

Comment 2 Alessandro Nakamuta 2011-05-11 06:36:00 UTC

Yes, it would be great. It's very annoying when we watching a video on youtube or reading a text and suddenly the screensaver popup.

Comment 3 Thomas Lübking 2011-05-11 12:20:49 UTC

@Allessandro:
different issue - you rather want a warning: "screen saver in 3,2,1 secs" to really prevent it (and that stupid flashplayer could as well just suspend the screensaver while playing a video)

We might have to suspend compositing with the screensaver showing up for driver bugs and security issues.
For those reasons, the the screensaver should probably always fade in internally.
(If you prevent unredirection of fullscreen windows, aka "suspend effects for fullscreen windows" the "fade" effect will probably fade in the screenlocker anyway - notice that this is not very efficient)

---
As a /very/ personal notice (NO determination about whether kwin should or will do this):

Ppl. should not use screensavers at all, that's just silly.
A (static black) "screensaver" may be used as explicit screen locker ("i'm leaving the terminal now to get a coffee, lock the screen so nobody can take a glimpse")  but for all other occasions xdpms (just turn the screen off) is the sane solution (why would you waste battery - and pollute the environment! ;-) - with a nifty animated OpenGL megashow *while you're not there to watch it anyway*??

Comment 4 Oswald Buddenhagen 2011-06-02 16:45:15 UTC

feel free to move the original report to kwin.

*** This bug has been marked as a duplicate of bug 183119 ***