Issue 114860

Summary: Avoid jumping pages when zooming
Product: Writer Reporter: hdu <hdu>
Component: codeAssignee: AOO issues mailing list <issues>
Status: CONFIRMED --- QA Contact:
Severity: Trivial    
Priority: P3 CC: alex, frank.loehmann, issues, Mathias_Bauer, michael.ruess, oliver.brinzing
Version: OOO330m9   
Target Milestone: ---   
Hardware: All   
OS: All   
Issue Type: ENHANCEMENT Latest Confirmation in: ---
Developer Difficulty: ---
Issue Depends on:    
Issue Blocks: 114909    

Description 2010-09-30 14:10:07 UTC
When zooming with a zoom gesture or the mouse wheel one sees page jumps around especially at smaller 
zoom levels, which looks quite unpleasant. This seems to be caused by the viewing mode transitioning 
from a one-page view-mode and the different multi-page view-modes.
Comment 1 2010-09-30 14:23:31 UTC
This problem becomes especially annoying when the zoom gets rids of its coarseness such as in the 
solution for issue 102807: The zooming gets super-smooth but the discontinuity of the page positions 
break the visual pleasantness.

The problem is visible even without the super-smooth zoom:
- create a dummy document with one page
- change the zoom slowly down to the level where the layout jumps to e.g. 1x2 mode
=> the page jumps to the left
Comment 2 Oliver-Rainer Wittmann 2010-09-30 15:00:29 UTC
fill CC list
Comment 3 Oliver-Rainer Wittmann 2010-09-30 15:03:38 UTC
The current zoom behavior is intended in order to get as early as possible the
second page fully shown.

Thus, there are requests which are somehow contradicting:
- super-smooth zooming without jumping of pages too much
- efficient usage of the document area in order to show as much pages as
possible beside each other.

I think further evaluations are needed to find out which of the above requests
have to fulfilled at which user action or to find out that one of the requests
can be skipped.
Comment 4 frank.loehmann 2010-09-30 15:32:27 UTC
The layout mode is set to 'Automatic' by default. With only one page the layout
behavior seems to be mysterious. One thing that we can do here is to stop
zooming out, if the entire page(s) is/are visible. But this requires a kind of
visual feedback that you have reached 'the end' (i.e. like iPad/iPod do it when
you reach the end of a scrollable list).

Furthermore painting of the pages could be optimized to avoid flickering and the
fixed drop shadow is much too prominent on a low zoom level.

Single page view as new layout default is another option, but I do not think
that we should go that way. 
Comment 5 Oliver Brinzing 2010-10-01 17:17:04 UTC
Comment 6 2010-10-08 09:59:05 UTC
So the goal to of avoid page jumps conflicts with keeping the page (or the MxN layout) centered. IMHO 
keeping the page and cursor positions non-jumping has a much higher priority than page-auto-centering. 
If these goals conflict the latter goal should be either ignored or even better be replaced by something that 
auto-centers the layout smoothly.

The idea to show a visual cue that zooming has reached its end is nice: While the zoom-events are coming 
in we could allow "over/under-zoom" and then smoothly zoom back to the actual limits when the zoom-
events cease.
Comment 7 eric.savary 2010-10-09 11:06:31 UTC
*** Issue 115001 has been marked as a duplicate of this issue. ***
Comment 8 eric.savary 2010-10-09 11:13:06 UTC
*** Issue 115001 has been marked as a duplicate of this issue. ***
Comment 9 eric.savary 2010-11-23 19:10:10 UTC
*** Issue 115744 has been marked as a duplicate of this issue. ***
Comment 10 Marcus 2017-05-20 11:35:13 UTC
Reset assigne to the default "".