Bug 290371 - regression in ktml selection: text shifts
Summary: regression in ktml selection: text shifts
Alias: None
Product: konqueror
Classification: Applications
Component: khtml (show other bugs)
Version: Git
Platform: OpenSUSE Linux
: NOR normal (vote)
Target Milestone: ---
Assignee: Konqueror Developers
: 271100 (view as bug list)
Depends on:
Reported: 2012-01-02 08:45 UTC by Martin Koller
Modified: 2012-09-09 15:12 UTC (History)
2 users (show)

See Also:
Latest Commit:
Version Fixed In:

I hope this makes clear what I mean. (37.66 KB, image/png)
2012-09-08 20:34 UTC, Andre Woebbeking

Note You need to log in before you can comment on or make changes to this bug.
Description Martin Koller 2012-01-02 08:45:30 UTC
Version:           0.0.1 (using Devel) 
OS:                Linux

I updated from 4.6.5 to 4.8-RC1 and now when viewing a web page
and start to select some text, the text paragraph gets redrawn and shifted to the right bottom by a few pixels.
See attached screenshot.

I've seen this also on other pages and even when not selecting but simply by hovering over the text.

Reproducible: Always

Steps to Reproduce:
see above

Actual Results:  
see above

Expected Results:  
no shifting

OS: Linux (i686) release
Compiler: gcc
openSuse 11.3
Comment 1 Christoph Feck 2012-01-02 15:57:49 UTC
Can you confirm that using "-graphicssystem native" for Konqueror fixes the issue? You probably have to kill the process, if you use preloading.
Comment 2 Martin Koller 2012-01-03 07:40:28 UTC
Yes, that solves the shifting problem.
Did the default graphicssystem change for 4.8 ?

However I still have an issue while selecting text so that the text selection does not correctly start below my mouse cursor.
E.g. when starting to select the above "-graphicssystem native"
and the mouse is over/at the left end of the - character, the selection starts with the character " left of it, and when I move the mouse to the right, the selection itself lags behind the mouse position. E.g. when I'm already with the mouse over the ending " the selection only is done until "-graphicssystem nativ

Don't know if this is related though.
Comment 3 Christoph Feck 2012-01-03 11:24:43 UTC
> Did the default graphicssystem change for 4.8 ?

If you mean Qt 4.8, then yes.

> the selection itself lags behind the mouse position

This is because Qt 4.8 now defaults to subpixel precision when layouting text positions. Konqueror has to make sure it computes the same widths for layouting/selecting as Qt uses for rendering, or alternatively force integer font metrics (which would make it look worse, but work correctly). Please report a new bug for Konqueror about this.
Comment 4 Christoph Feck 2012-01-03 11:29:13 UTC
*** Bug 271100 has been marked as a duplicate of this bug. ***
Comment 5 Martin Koller 2012-01-03 11:45:53 UTC
For the selection I created bug 290485
Comment 6 Christoph Feck 2012-07-15 20:34:55 UTC
I can no longer reproduce this issue with Qt 4.8.2 on today's KDE.
Comment 7 Christoph Feck 2012-07-19 03:42:10 UTC
Too soon. I can reproduce with http://www.turboprint.info/download.html
Comment 8 Andre Woebbeking 2012-09-08 20:28:33 UTC
I'm not sure whether I've the same issue: on e. g. www.heise.de/newsticker at the bottom everything is shifted a bit when I scroll down. If I hover some links the page seems to be relayouted and the rendering is correct. 

I'll attach a snapshot.
Comment 9 Andre Woebbeking 2012-09-08 20:34:09 UTC
Created attachment 73755 [details]
I hope this makes clear what I mean.
Comment 10 Andre Woebbeking 2012-09-09 15:12:32 UTC
I forgot to mention that "-graphicssystem native" helps here too.