Bug 133273 - When I write a text in Writer and use the font Tahoma, then some letters stick together.
Summary: When I write a text in Writer and use the font Tahoma, then some letters stic...
Status: RESOLVED DUPLICATE of bug 144862
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: Writer (show other bugs)
Version:
(earliest affected)
6.1.5.2 release
Hardware: x86-64 (AMD64) Linux (All)
: medium normal
Assignee: Not Assigned
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2020-05-22 12:19 UTC by schabei
Modified: 2022-08-05 23:56 UTC (History)
4 users (show)

See Also:
Crash report or crash signature:


Attachments
How it looks (31.24 KB, image/png)
2020-05-22 12:21 UTC, schabei
Details
Beispiel für jede Textgrösse.odt (19.19 KB, application/vnd.oasis.opendocument.text)
2020-05-22 12:23 UTC, schabei
Details
Writer bad spaces, Tahoma, with Anti-Aliasin, Font10.5.png (92.80 KB, image/png)
2020-05-22 12:24 UTC, schabei
Details
Font DejaVu Sans.png (13.71 KB, image/png)
2020-05-22 12:25 UTC, schabei
Details
Tahoma Font File (142.40 KB, application/zip)
2020-05-23 20:04 UTC, schabei
Details
This is how it looks with version 7.0.4.2 (30.08 KB, image/png)
2020-12-31 16:30 UTC, schabei
Details
This is my writer version (124.00 KB, image/jpeg)
2020-12-31 16:33 UTC, schabei
Details

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Description schabei 2020-05-22 12:19:43 UTC
Description:
When you want to see, what I see on my PC, open the attached file:
"Writer bad spaces, Tahoma, without Anti-Aliasin Font10.5.png"

When opening the picture: Make sure that you view the images 1:1 (100%) and that anti-aliasing is switched off in the image viewer. (For example Menu->Edit->Settings in "Nomacs").

What can you see in the picture?
An example: In the word "Kunde" with the arrow, "u" and "n" stick together. But in the word "wundersamen", "u" and "n" do not stick together. There are a lot further examples in this text, without arrows.

So this is what bothers me: The spaces between the letter look not always the same.

(Please note: I do not want to use such modern technique like Anti-Aliasing. I think Anti-Aliasing is good for 4K monitors. But I have a 1280x1024 pixel LCD monitor. I know that most people use Anti-Aliasing on a 1280x1024 LCD monitor. But I do not like it. I would rather have a crystal-clear writing with stairs than a light blurred font without steps. ) 


Letters stick together at Tahoma without anti-aliasing
-----------------------------------------------------------------------------------

-Where can we observe this?
Answer: In the LibreOffice Writer. At any font size. The most error-free font size is 10 (108dpi).
Please have a look at the attached File "Beispiel für jede Textgrösse.odt"

-Can you see the phenomenon also in Featherpad and Geany?
Answers: At font size 9 (108dpi) it occurs in Wirter, but not in Featherpad.
At font size 9 (108dpi) it occurs in Writer, but not in Geany.

-What happens if you enable anti-aliasing (with 10.5)?
Answer: Then the spacing is better. But there are still a few bad spacing issues. Please compare the attached file "Writer bad spaces, Tahoma, with Anti-Aliasin, Font10.5.png"

-What are the letters that always stick together?
Answer: That is different. Sometimes they stick together, a few words later they don't anymore.

-Does the phenomenon also occur with other fonts? Microsoft fonts, or even Linux fonts, like DejaVu sans?
Answer: DejaVu Sans: Yes, but much less. Arial: Much less, but irregular spacing. Attached is an example for DejaVu: File "Font DejaVu Sans.png"

Steps to Reproduce:
1. Install Tahoma on your Linux system
2. Disable Anti-Aliasing on your System
3. Disable in Writer "Smooth screen fonts"
4. Disable in Writer "use Anti-Aliasing"
5. Open the attached document "Beispiel für jede Textgrösse.odt"

Actual Results:
The spaces between letters are irregular. Some letters stick together. Other have normal spaces. Other have too much space between them.

Expected Results:
The visual impression should be that all distances between the individual letters are the same.


Reproducible: Always


User Profile Reset: Yes



Additional Info:
I have tried to enable OpenGL. But when I enable it, close Writer. Open it again, then OpenGL is disabled again. *Confused.

Output from terminal:
$ glxinfo | grep OpenGL
OpenGL vendor string: Intel Open Source Technology Center
OpenGL renderer string: Mesa DRI Intel(R) Haswell Desktop 
OpenGL core profile version string: 4.5 (Core Profile) Mesa 18.3.6
OpenGL core profile shading language version string: 4.50
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 3.0 Mesa 18.3.6
OpenGL shading language version string: 1.30
OpenGL context flags: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.1 Mesa 18.3.6
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.10
OpenGL ES profile extensions:
Comment 1 schabei 2020-05-22 12:21:57 UTC
Created attachment 161138 [details]
How it looks
Comment 2 schabei 2020-05-22 12:23:17 UTC
Created attachment 161139 [details]
Beispiel für jede Textgrösse.odt
Comment 3 schabei 2020-05-22 12:24:32 UTC
Created attachment 161140 [details]
Writer bad spaces, Tahoma, with Anti-Aliasin, Font10.5.png
Comment 4 schabei 2020-05-22 12:25:24 UTC
Created attachment 161141 [details]
Font DejaVu Sans.png
Comment 5 Telesto 2020-05-22 20:34:42 UTC
Is it possible to update to a more recent version of LibreOffice?
Comment 6 schabei 2020-05-23 08:28:48 UTC
This is the latest version from the Package manager of my Linux distribution.
Comment 7 schabei 2020-05-23 15:21:49 UTC
I have tried out now Writer 6.4.4.1:
It's the same.
Comment 8 Telesto 2020-05-23 18:24:45 UTC
Sorry, for all the questions.. Source and maybe also version of the Tahoma font
I don't reproduce it on Windows
Comment 9 schabei 2020-05-23 20:04:27 UTC
Created attachment 161201 [details]
Tahoma Font File

This is the Tahoma Font I have used.
Comment 10 schabei 2020-05-23 20:05:50 UTC
It's version 2.60. But with newer versions it's the same.
Comment 11 Telesto 2020-05-23 20:28:37 UTC
I added the font specialist.. may take a few days
Comment 12 Dieter 2020-12-01 08:28:12 UTC
I can't reproduce it with

Version: 7.0.3.1 (x64)
Build ID: d7547858d014d4cf69878db179d326fc3483e082
CPU threads: 4; OS: Windows 10.0 Build 19042; UI render: Skia/Raster; VCL: win
Locale: de-DE (de_DE); UI: en-GB
Calc: CL

Could you please try to reproduce it with the latest version of LibreOffice from https://www.libreoffice.org/download/libreoffice-fresh/ ? LO now uses Skia for rendering, so perhaps this solves your problem.

I have set the bug's status to 'NEEDINFO'. Please change it back to 'UNCONFIRMED' if the bug is still present in the latest version.
Comment 13 schabei 2020-12-31 16:30:12 UTC
Created attachment 168606 [details]
This is how it looks with version 7.0.4.2
Comment 14 schabei 2020-12-31 16:33:09 UTC
Created attachment 168607 [details]
This is my writer version

I have updated my LibreOffice via my package manager (backports version).
In the picture you see information about my writer version.
Comment 15 schabei 2020-12-31 16:34:08 UTC
So it's still the same problem.
Comment 16 Telesto 2020-12-31 17:37:07 UTC
Hmm the attached font appears to be Tahoma 2.60. Looks old to me. I'm having version 6.05 on my system.

Any change to download a more recent version somewhere?
Comment 17 V Stuart Foote 2020-12-31 18:12:45 UTC
So don't use the Tahoma font where deficiencies (gpos, kern tables) and hinting issues make for bad kerning and unreliable font to use on a GTK3 (pango harfbuzz) based DE.

You could drop back and try the 'gen' backend, but not clear that would improve the kerning with your os/DE

At some point implementation of floating point positioning on VCL canvas for bug 103322 would allow sub-pixel rendering, until then fonts must render without benefit of horizontal hinting.

=-ref-=
https://gitlab.gnome.org/GNOME/pango/-/issues/463

https://github.com/harfbuzz/harfbuzz/issues/2394

*** This bug has been marked as a duplicate of bug 88991 ***
Comment 18 Aron Budea 2022-08-05 23:56:34 UTC

*** This bug has been marked as a duplicate of bug 144862 ***