Bug 362826

Summary:	Morphing popups effect causes drag pixmaps to flicker
Product:	[Plasma] kwin	Reporter:	Kai Uwe Broulik <kde>
Component:	effects-various	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	NOR
Version:	git master
Target Milestone:	---
Platform:	Other
OS:	Linux
See Also:	https://bugs.kde.org/show_bug.cgi?id=361296 https://bugreports.qt.io/browse/QTBUG-52560
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Drag pixmap flicker

Description Kai Uwe Broulik 2016-05-08 20:22:21 UTC

I know Qt shouldn't mark those windows as tooltips, but:

When I drag a file eg. in FolderView and I stop moving the mouse with the button still pressed, and I then start moving the mouse, the CrossFadePrevious animation causes the pixmap to fade/flicker, if I disable the fade animation in the effect, this goes away.

Reproducible: Always

Steps to Reproduce:
1. Enable "morphing popups" effect, enabled by default
2. Start dragging a file
3. While still pressing the mouse button stop moving the mouse and start moving again

Actual Results:  
The drag pixmap flickers/fades briefly

Expected Results:  
The drag pixmap stays as it is

Comment 1 Kai Uwe Broulik 2016-05-08 20:22:46 UTC

Created attachment 98847 [details]
Drag pixmap flicker

Comment 2 Thomas Lübking 2016-05-08 20:45:22 UTC

>  Qt shouldn't mark those windows as tooltips
This should be caught by the supposed* fix for bug #361296 by correctly marking the DnD window?**
https://bugreports.qt.io/browse/QTBUG-52560
http://commits.kde.org/plasma-integration/3500c766f107d7ab2520c809cbf09f053a6f8062

That aside, it looks like the crossfade happens from an empty texture, ie. the old texture is lost??


---
*the commit cannot fix bug #361296 because qt5 dnd causes something™ t hat's slow at least on nvidia and doesn't drop/compress events, thus the resolution of the bug in contrast to the patch

** though the eventfilter only looks for "inherits("QShapedPixmapWindow")" - could easily fail on QtQtuick

Comment 3 Kai Uwe Broulik 2016-05-08 20:56:06 UTC

> though the eventfilter only looks for "inherits("QShapedPixmapWindow")" - could easily fail on QtQtuick

It also affects Dolphin and the File Open dialog

Comment 4 Kai Uwe Broulik 2016-05-08 20:57:20 UTC

Hang on, I haven't updated my plasma-integration.

Comment 5 Kai Uwe Broulik 2016-05-08 20:59:18 UTC

Hooray \o/ Works now in both widgets and QtQuick apps.

Doesn't explain the original bug with the supposed fade from empty pixmap though.

Comment 6 Thomas Lübking 2016-05-08 21:09:00 UTC

Does crossfading work as expected otherwise (eg. maximization effect)?
If so, I sense relation to the slow DnD issue (for creating ARGB drawables is still rather slow on nvidia) - the window is probably somehow re-created (or cleared for another reason)

Comment 7 Martin Flöser 2016-05-11 07:48:02 UTC

@Kai: given comment #5: is this one RESOLVED WORKSFORME?

Comment 8 Martin Flöser 2016-10-28 19:52:31 UTC

Assuming fixed, if not please reopen.