Bug 246622

Summary: Maximised windows leave a line of desktop background above panel with compositing enabled
Product: [Plasma] kwin Reporter: Ralf Jung <post>
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: normal CC: plasma-bugs-null
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: A screenshot showing the issue (right half is with composite, left half without)

Description Ralf Jung 2010-08-03 17:20:40 UTC 
Version:           unspecified (using KDE 4.4.2) 
OS:                Linux

With composite enabled, when I maximise a window, a 1 pixel line of the desktop background is visible between the panel and the window. When I disable composite, that line is coloured in the background colour of the panel, so that it is perceived as part of the panel.

Reproducible: Always

Steps to Reproduce:
Just enable compositing and maximize a window. The effect might be hard to notice on some desktop backgrounds though.

Actual Results:  
The window is one pixel too narrow in height, leaving one pixel of desktop background visible (or the panel reports its height one pixel too high).
I attached a screenshot showing the effect: The left half has compositing disabled, the right one has it enabled. You can clearly see the black line which is coming from the desktop background.

Expected Results:  
The lowest window pixel should be directly above the panel.

OS: Linux (x86_64) release 2.6.32-24-generic
Compiler: cc

I am using the default Plasma style.
Comment 1 Ralf Jung 2010-08-03 17:21:36 UTC 
Created attachment 49782 [details]
A screenshot showing the issue (right half is with composite, left half without)
Comment 2 Thomas Lübking 2010-08-03 17:46:04 UTC 
attaching plasma since this is (if not intended) likely a panel bug (mismatch between the set and the visual strut)
Comment 3 Martin Flöser 2010-08-26 21:32:55 UTC 

*** This bug has been marked as a duplicate of bug 248570 ***