Bug 148957 - Animations on Libre 7 Impress slides noticeably blink, badly distracting the audience. [EDITING]
Summary: Animations on Libre 7 Impress slides noticeably blink, badly distracting the ...
Status: NEW
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: Impress (show other bugs)
(earliest affected) release
Hardware: All Windows (All)
: medium normal
Assignee: Not Assigned
Keywords: bibisected, bisected, regression
: 151868 (view as bug list)
Depends on:
Blocks: Skia
  Show dependency treegraph
Reported: 2022-05-06 03:04 UTC by gearhead
Modified: 2023-10-09 17:29 UTC (History)
6 users (show)

See Also:
Crash report or crash signature:

Test-case .odp file (single slide) demonstrating animations that blink. (294.62 KB, application/vnd.oasis.opendocument.presentation)
2022-05-06 03:04 UTC, gearhead
Bibisect log (4.19 KB, text/plain)
2022-05-09 18:22 UTC, Telesto

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Description gearhead 2022-05-06 03:04:33 UTC
Created attachment 179957 [details]
Test-case .odp file (single slide) demonstrating animations that blink.

For years, I've used animation to successively disclose information on a slide.
As a typical example (see below), one call-out may appear (often using Wipe),
then a second call-out appear, and so on. Audiences like it.

     CAPTION_1  o--------->   [ ][ ][ ]
                              [ ][ ][ ]   <--------o CAPTION_2

General Problem Description:
These techniques worked fine in Libre 4, and the Animation dialog (Alt-S-A)
was easy to get to, and use. In Libre 7, the same animations are buggy, and
the dialog is cumbersome and hard to read -- especially when you have 4 or 5 animations on one slide. The familiar shortcut key no longer functions.

Specific Bug:
As shown in the attached test case, when CAPTION 2 wipes, CAPTION 1's line
temporarily vanishes. To the audience, all the preceding captions BLINK off
and on again. It's very distracting and confusing, and defeats the purpose of animating a presentation in the first place.

Also, if the call-out lines have features (ending circles or arrowheads),
these are displayed out-of-synch with the body of the line.

Humble Request:
Can Libre just discard version 7 animation and return to version 4???
Comment 1 Timur 2022-05-06 08:09:27 UTC
Please write your Help-About and test with changed graphics in Options-View.
Comment 2 Julien Nabet 2022-05-06 19:24:25 UTC
2 things you can try:
- https://wiki.documentfoundation.org/QA/FirstSteps
- upgrade to brand new LO 7.3.3
Comment 3 gearhead 2022-05-07 19:28:37 UTC
I did notice additional buggy behavior in Libre 7.2 Impress animations.
This occurred in the same presentation -- which is perhaps pushing the tool's
limits, using 1--8 animations per slide in a lengthy presentation.

While editing the animations on one slide, the tool ALTERS animation settings
on previous slides. For example:

a. A Delay was mysteriously changed from 0.5 sec to 100,000 sec.
   This shows up when the user performs an On Click . . . . and
   nothing happens for a long time!

b. A Wipe entrance was changed to a Circle.

c. The new Animation dialog is cumbersome to use when you have more than
   a few animations per slide. Items on the slide somehow become grouped
   together; when you think you're editing one item, the dialog applies
   the settings to another item; the list of animations does not stay put,
   but often jumps -- so you have to keep scrolling up or down the list.
Comment 4 Timur 2022-05-09 10:46:58 UTC
Blink no repro GDI, repro SKIA. Test 7.4+. New.
Meaning that you can circumvent by turning off Skia in Tools-Options.
Comment 5 V Stuart Foote 2022-05-09 15:02:29 UTC
The "blink" looks to be the canvas frame being cleared by the "wipe" transition used for each of the Bézier curves or group objects of the test case slide.

So, yes the could be a logic error introduced in the way the stack of annimations is being processed/reprocessed to canvas for multiple transitions/elements used on a slide. 

Can agree that each new transition should not result in the prior transistion effect being reapplied. 

But, Skia or default GDI rendering has no effect here, the redraw "blink" of the Bézier curve animations occur for both, likewise for the Group object.

Version: (x64) / LibreOffice Community
Build ID: 49f2b1bff42cfccbd8f788c8dc32c1c309559be0
CPU threads: 8; OS: Windows 10.0 Build 19044; UI render: Skia/Vulkan; VCL: win
Locale: en-US (en_US); UI: en-US
Calc: CL

There is a regression, testing same system with an old build has no issues with the annimated element transitions.

Version: (x64)
Build ID: 2524958677847fb3bb44820e40380acbe820f960
CPU threads: 8; OS: Windows 6.19; UI render: GL; 
Locale: en-US (en_US); Calc: group

Comment 6 Telesto 2022-05-09 18:22:25 UTC
Created attachment 180022 [details]
Bibisect log

Bisected to:
author	Luboš Luňák <l.lunak@collabora.com>	2020-09-24 13:32:51 +0200
committer	Luboš Luňák <l.lunak@collabora.com>	2020-09-29 09:55:34 +0200
commit 6f224a17dbf635319503a81ce4038b1ae2ad6de0 (patch)
tree 4c275367241d1fa61e0912577a3d3e1aabad19ea
parent 748723883a626b499f605d7a5bad92e25b69a0e4 (diff)
make vclcanvas try directly VCL for drawing stroked polygon (tdf#136933)
There's no point in trying to do all the stroking stuff manually
if the VCL function can do it and better/faster.
Comment 7 Buovjaga 2023-03-03 14:21:29 UTC
*** Bug 151868 has been marked as a duplicate of this bug. ***