Oversized UI fonts on gtk/gnome-based system

[Chris Jones]

I have just noticed that calibre's UI fonts have become quite large all of a sudden.

By 'quite large' I mean that where calibre normally displays some 90+ books on its main screen it now displays only 37. So I'd say the the font is at least twice the height that it should be.

The problem seems to have started with the current 3.47.1 release… presumably because calibre now interfaces with a newer version of Qt (Qt5?).

I have had this problem before with QT applications in a mostly gnome context. On linux this is handled by a gnome/kde compatibility layer and a configuration tool called qt5ct that lets the user change such things as UI font-family, font-size, theme, icon theme… etc.

At least where the font-size is concerned, this 3.47.1 release of calibre does not honor the settings made via qt5ct.

This issue does not affect other Qt5 applications I have looked at (okular, sigil, inkscape, frescobaldi…) which are fine in this respect: if I change the font size via qt5ct these applications respond to my changes. Calibre ignores the changes.

I am running an up-todate debian 10 — aka 'buster'.

Please advise.

[kovidgoyal]

Preferences->Look & Feel->Interface font and Preferences->Look & Feel->Adjust for high resolution screens

[Chris Jones]

Originally Posted by kovidgoyal

Preferences->Look & Feel->Interface font and Preferences->Look & Feel->Adjust for high resolution screens

That was not the problem but as it turns out you did point me in the right direction.

I had not looked at (never mind changed) my calibre settings for at least 5 years and completely forgotten that calibre has its own mechanism allowing the user to set the UI font-size and font-family.

What actually happened is that some of my settings were somehow corrupted and since I the problem occurred about the time I upgraded to 3.47.1 I suspected it might somehow be related.

My calibre Look & Feel screen had 'verdana 12pt' instead of the original 'verdana 6pt'…

Another settings on that same screen that was reset or corrupted was 'extra spacing between rows…' that I set at the maximum negative value of -20px… it had simply vanished.

After I cycled calibre I also noticed that the top window where you get to see the covers was not showing. Something quite useless of course… but that I honestly couldn't do without because it gives calibre its character!

Thanks for prompt response…

CJ

[Chris Jones]

Originally Posted by kovidgoyal

Preferences->Look & Feel->Interface font and Preferences->Look & Feel->Adjust for high resolution screens

Would you consider adding — possibly via a check box or radio button… an option such as 'use system font' — i.e. the font-family and font-size defined for all the applications that run on your desktop. And keep the calibre-specific UI font setting as some kind of escape hatch in case the desktop-wide setting is unsatisfactory?

IOW —

1. Check the box that says you want to use the font specified via gnome or kde settings. Cycle calibre and you're done.

2. Uncheck the box. Gives you access to the setting that lets you set a specific font & font-size that overrides the gnome/kde setting.

Naturally the 'use system font' could be the default so new users … users who install a new system… switch to a different desktop… etc. are automatically presented with a UI that uses the same font & font-size as their other applications.

Or is there a technical issue with this that I am unaware of that would cause undesirable effects or even make this approach impossible?

[kovidgoyal]

If you never set that option, it defaults to using system font. Of courseon linux "system font"is meaningless since what the system font is varies from toolkit to tolkit and desktop env to desktop env. Qt has some heauristics to detect it, which may or may not work.