hello,
I was trying to switch from KDE4 to 5, however, I have encoutered the serious problem with font rendering which makes plasma5 unusable for me.
In order to keep clear, and well readable font I use MS truetype fonts (Arial and others) with antialiasing disabled for these specific font types.
When upgrading to plasma 5 on the old KDE4 installation, after the first login everything is fine. The Arial font is well rendered.
However, after the first logging out, the character spaces are no longer properly kept and the distances are totally uneven. Adjacent characters have different spacing, sometimes they touch each other, sometimes they are pushed away.
You can see the screenshot here: http://149.156.92.50/kde5.jpg
Anyone have an idea how to fix this annoying problem? Thank you!
Marek

That looks a hinting issue - check and adjust the hinting configuration for these fonts (autohinter or font hints, hinting strength)
I'd say it's _not_ the autohinter and MS declared ligatures here (good) without fixing the combined width (bad) - also affects "sh" and "rt".

Why and how hinting changes across logins, I unfortunately can't say (plasma overriding your settings?? new font config files with the new distro? NOTICE that the KDE5 config path moved from ~/.kde*/config to ~/.config!)

PS - OT:
> In order to keep clear, and well readable font I use MS truetype fonts

Yeah, no. Sorry.
Consider using fonts from a source that actually knows a tiny bit about typography.
MS fonts are utter **** (and arial is but a poor helvetica knock-off, MS wanted to save license costs back then)

And no: this is not generic MS bashing. MS fonts* are just terrible, no matter what one thinks about their OS or the company.
Adobe distributes its "Source" font for free and intels "Clear" and even googles "Droid" or the usual "DejaVu" (aka Bitsreams "Vera") are all way ahead of MS Arial. You may also try Apples new SanFrancisco (but I'm not sure about it's hinting and stuff - little experience)

*I'll make an exception for Consolas here - it has a nice and usable design, good whitespace and one can't largely fail hinting in a monospace font =)

Thank you for all the detailed tips and remarks. I'll definitelly follow them!
marek

Finally, I have found a solution for proper font spacing in KDE5. hintstyle should be set to hintmedium in the .fonts.conf file. Thank you for the suggestions.

Code: Select all

<match target="font">
    <test qual="any" name="family">
      <string>Arial</string>
    </test>
   <!-- pixelsize or size -->
    <test compare="less_eq" name="pixelsize" qual="any">
      <double>18</double>
    </test>
    <edit mode="assign" name="antialias">
      <bool>false</bool>
    </edit>
    <edit mode="assign" name="hintstyle">    <const>hintmedium</const>  </edit>
  </match>


hintfull is even better.