Bug 145962 (Kerning) - [META] Bugs related to kerning/font spacing (cramped/to width/wiggling)
Summary: [META] Bugs related to kerning/font spacing (cramped/to width/wiggling)
Status: NEW
Alias: Kerning
Product: LibreOffice
Classification: Unclassified
Component: LibreOffice (show other bugs)
(earliest affected) release
Hardware: All All
: medium normal
Assignee: Not Assigned
Depends on: 46817 105936 113134 116969 122457 122664 133881 143323 143805 146078 146453 152123 154579 155490 52028 61444 94597 97171 97261 103322 103765 104223 104921 107155 111631 114813 122626 123182 124116 128987 132705 136548 138919 139296 140083 140101 140161 140197 140738 140740 141749 142940 144862 145277 145648 145934 146006 146073 146080 146288 146439 146515 146879 147406 157849 158997
Blocks: Fonts
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Reported: 2021-11-30 10:32 UTC by Telesto
Modified: 2024-01-25 22:01 UTC (History)
3 users (show)

See Also:
Crash report or crash signature:


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Description Telesto 2021-11-30 10:32:52 UTC

Actual Results:

Expected Results:

Reproducible: Always

User Profile Reset: No

Additional Info:
Comment 1 Telesto 2021-11-30 11:33:00 UTC
There plenty of commits which introduce/uncover/hide/mask/resolve issues related to spacing/glyph rendering over the years.
The can be related or totally unrelated. Or worst of all mixture of all sorts of (unintended) interactions between different changes. 

author	Michael Stahl <mstahl@redhat.com>	2013-06-15 21:25:27 +0200
committer	Michael Stahl <mstahl@redhat.com>	2013-06-20 00:34:38 +0200
commit 6db39dbd7378351f6476f6db25eb7110c9cfb291 (patch)
tree 0f9321d40740e87e80d8ed05a7c7f474d5310afd
parent e012f326c1c32c053304998a6826cb322f2c7728 (diff)
fdo#52028: sw: let text formatting ignore RSID in automatic styles


author	Khaled Hosny <khaledhosny@eglug.org>	2016-12-20 01:36:34 +0200
committer	Khaled Hosny <khaledhosny@eglug.org>	2016-12-20 05:14:25 +0000
commit 9eb4b14ffa57cd7bbdf0fc43096f5f1e65c8e388 (patch)
tree 535d14ede1db48f0c1651b27f0ebd78579819b47
parent 2e9c02feca732f6dd012ccbe5d7c6853c64075a5 (diff)
tdf#103765: Round positions instead of truncating


author	Tim Eves <tim_eves@sil.org>	2016-03-08 14:46:49 +0700
committer	Michael Meeks <michael.meeks@collabora.com>	2016-03-14 17:52:41 +0000
commit 620a1351a7627246f139a54a8cc3b35fa7ef8434 (patch)
tree 60aa0ea26e31e58b7db2c12cb9753a756ad40399
parent bf81970071261e99c5921ae1b8748fde82b8e077 (diff)
tdf#97171: Use DirectWrite for OpenGL glyph caching

"Fix horizontal occsional alingment issues in OpenGL cached glyphs. The
left edge of the src location rectangle for the first glyph in a cache
chunk would set to extraspace and not zero, but all other rectangles
in the chunk would be set from the aEnds array. This produced a bug
where only certain letters would be mispositioned, proportional to the
fonts point size."


author	Andreas Heinisch <andreas.heinisch@yahoo.de>	2021-07-05 22:32:52 +0200
committer	Noel Grandin <noel.grandin@collabora.co.uk>	2021-07-12 20:20:41 +0200
commit 988acfabb22ec9281c0fe70ed40b574eeceae90b (patch)
tree 92cacea27b8559a61c8f81ea0485bfc4bfd1a0cf
parent ac3207d3b2c3b6580de14132fd12e9c6fedc6502 (diff)
tdf#140197 - Letter cut off at certain zoom-level
regression from
	commit 4b2d4f3c4a68361a6bc03c9ab110ce9376b14b20
	tdf#119227 fix freeze when copying a large bulleted list


From bug 112849 comment 4:
> Fixing kashida once and for all requires 1) making the communication between
> Writer and VCL explicit e.g. have a separate “kashida insertion points”
> array 2) Kill DX array for good and enter the 21 century (it is an API
> “inspired” by Windows 3.1 3) Fix rounding errors by preserving fractional
> glyph positions in a way or another.
Comment 2 Telesto 2021-12-01 18:14:30 UTC
In bug 144862 connection being made between sidebar and wiggling. The presence of the sidebar mitigated the wiggling for a while. [In in a total different case they adding of "window expand handle" started to cause table to go out of automatic mode]

Which sometimes suggests that the canvas size being interacts by the presence of sidebar. Another interesting observation hold bug 145648. Where kerning is different between comment box and canvas for the same text.
Comment 3 Telesto 2021-12-17 08:48:03 UTC
Another code pointer from Caolán McNamara (see bug 145934 comment 4)

vcl/source/outdev/text.cxx using base position for better rounding a.k.a. "dancing 
characters" in OutputDevice::ImplLayout seems to be a reason this happens

commit 1bd5948782dad86141356ebbb4fad37e5181c296
Author: Vladimir Glazounov <vg@openoffice.org>
Date:   Wed May 28 11:30:40 2003 +0000
    2003/05/12 14:44:36 hdu #109377# better rounding for pDXArray, CJK underline position

there seems to be a one pixel different in the starting pos from when the editengine is "active" and when it's not which results in the dancing characters we still see

Commit https://git.libreoffice.org/core/commit/56186db93b7777f7b99a8fbfce82b775e24b7695
does fix bug 145934 and changes the behaviour of bug 144862 (different zoom-level/window size required to trigger, but fundamental problem still present)