Bug 155150 - Bad font rendering in Writer as opposed to Calc after deactivating anti-aliasing in KDE system settings (independent of VCL plugin)
Summary: Bad font rendering in Writer as opposed to Calc after deactivating anti-alias...
Status: RESOLVED DUPLICATE of bug 156200
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: Writer (show other bugs)
Version:
(earliest affected)
7.4.6.2 release
Hardware: x86-64 (AMD64) Linux (All)
: low trivial
Assignee: Not Assigned
URL:
Whiteboard:
Keywords:
Depends on:
Blocks: Font-Rendering
  Show dependency treegraph
 
Reported: 2023-05-04 17:38 UTC by mdcclxv
Modified: 2024-08-21 17:57 UTC (History)
6 users (show)

See Also:
Crash report or crash signature:


Attachments
Writer vs Calc with anti-aliasing disabled (15.65 KB, image/png)
2023-05-04 17:40 UTC, mdcclxv
Details
Writer vs Calc with anti-aliasing disabled (29.08 KB, image/png)
2023-05-04 17:45 UTC, mdcclxv
Details

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Description mdcclxv 2023-05-04 17:38:31 UTC
Description:
When anti-aliasing is disabled, using the same Verdana font and size, Writer renders everything ugly as opposed to Calc which renders it clean and crisp.

Steps to Reproduce:
1. Install Verdana font
2. Create a Calc document using Verdana 11
3. Create a Writer document using Verdana 11

Actual Results:
Font rendering in Writer is totally ugly as opposed to Calc which does perfectly.

Expected Results:
Clean and crisp font rendering in Writer as well.


Reproducible: Always


User Profile Reset: No

Additional Info:
Version: 7.4.6.2 / LibreOffice Community
Build ID: 40(Build:2)
CPU threads: 16; OS: Linux 6.2; UI render: default; VCL: kf5 (cairo+xcb)
Locale: en-US (en_US.UTF-8); UI: en-US
7.4.6-1
Calc: threaded
Comment 1 mdcclxv 2023-05-04 17:40:20 UTC
Created attachment 187087 [details]
Writer vs Calc with anti-aliasing disabled
Comment 2 mdcclxv 2023-05-04 17:45:40 UTC
Created attachment 187088 [details]
Writer vs Calc with anti-aliasing disabled
Comment 3 Dieter 2023-05-13 14:00:15 UTC
I can't confirm with

Version: 7.5.3.2 (X86_64) / LibreOffice Community
Build ID: 9f56dff12ba03b9acd7730a5a481eea045e468f3
CPU threads: 4; OS: Windows 10.0 Build 19045; UI render: Skia/Raster; VCL: win
Locale: de-DE (de_DE); UI: en-GB
Calc: CL threaded

Mdcclxv, could you please retest with LO 7.5 and give feedback? Thank you.
=> NEEDINFO
Comment 4 Buovjaga 2023-05-15 13:16:44 UTC
I went to Tools - Options - View and unchecked both "Use anti-aliasing" and "Screen font antialiasing", but I can't get the text to look like in your screenshots. Can you help me find the correct option?
Comment 5 Buovjaga 2023-05-15 13:22:39 UTC
I realised that I need to go to System settings - Appearance - Fonts in KDE and deactivate anti-aliasing there. After that, I could see Writer renders Verdana worse than Calc.
Comment 6 Buovjaga 2023-05-15 13:22:51 UTC
Arch Linux 64-bit, X11
Version: 7.6.0.0.alpha1+ (X86_64) / LibreOffice Community
Build ID: d2756dbd9b11bdfbf1d576381b8f9846a6fb7070
CPU threads: 8; OS: Linux 6.3; UI render: default; VCL: kf5 (cairo+xcb)
Locale: fi-FI (fi_FI.UTF-8); UI: en-US
Calc: threaded
Built on 15 May 2023
Comment 7 Michael Weghorn 2024-08-02 16:29:38 UTC
In a quick test, I see no difference in how the document content is rendered in Writer with either the kf5 or gtk3 VCL plugins. (The latter can be enabled by starting LO with the environment variable SAL_USE_VCLPLUGIN=gtk3 set.)

However, I don't actually have Verdana installed here.

Can you verify that using either VCL plugin doesn't make a difference?
(Please double-check the VCL plugin in use in Help -> About LibreOffice)?

tdf#156200 might be related.
Comment 8 mdcclxv 2024-08-06 16:14:57 UTC
@Michael

My LO is using the gtk3 plugin WITHOUT having SAL_USE_VCLPLUGIN set. How come?

Not sure if you got it right. The difference I'm talking about is between Writer and Calc (and not between the two plugins while only using Writer). See the screenshot attached to the ticket. The key here is to disable anti-aliasing and use a font designed for that (like Verdana).
Comment 9 Michael Weghorn 2024-08-06 16:31:10 UTC
(In reply to mdcclxv from comment #8)
> My LO is using the gtk3 plugin WITHOUT having SAL_USE_VCLPLUGIN set. How
> come?

The default VCL plugin depends on the desktop environment and is e.g. gtk3 for GNOME, kf5 for KDE Plasma 5 and kf6 for KDE Plasma 6. Depending on what's installed, not all of those might be present, in which case a fallback to another one can happen.

> Not sure if you got it right. The difference I'm talking about is between
> Writer and Calc (and not between the two plugins while only using Writer).
> See the screenshot attached to the ticket. The key here is to disable
> anti-aliasing and use a font designed for that (like Verdana).

Thanks for the clarification. That's what I was somewhat expecting, and trying to clarify. (Sometimes the way that something is rendered differs between VCL plugins, but that's usually more for other UI elements, not the document content.)

This ticket was set as blocking for meta ticket tdf#102495, suggesting it's an issue specific to the kf5 VCL plugin. Based on your feedback, that's not the case, so I'm removing that from the "Blocks" field.
Comment 10 mdcclxv 2024-08-06 16:36:42 UTC
Well, then something is really off with the plugin, because I have Plasma 6 installed, up-to-date. I don't mean to divert the thread, but can you provide a link on how to set the active plugin?

Or is it enough to just set SAL_USE_VCLPLUGIN=kf6 ?
Comment 11 Michael Weghorn 2024-08-06 16:40:36 UTC
(In reply to mdcclxv from comment #10)
> Well, then something is really off with the plugin, because I have Plasma 6
> installed, up-to-date. I don't mean to divert the thread, but can you
> provide a link on how to set the active plugin?
> 
> Or is it enough to just set SAL_USE_VCLPLUGIN=kf6 ?

Yes, that's how you can force the use of that plugin. Note however that TDF builds don't include the kf6 VCL plugin, so it won't be used with those. So that depends on using distro packages, and your distro packaging the kf6 VCL plugin.
Comment 12 Buovjaga 2024-08-21 17:57:04 UTC
(In reply to Buovjaga from comment #5)
> I realised that I need to go to System settings - Appearance - Fonts in KDE
> and deactivate anti-aliasing there. After that, I could see Writer renders
> Verdana worse than Calc.

Maybe it's the switch to Wayland, but Calc and Writer look equally bad to me now.

I will close as dupe as the newer bug has more info and links. Likely this will never get fixed.

*** This bug has been marked as a duplicate of bug 156200 ***