D24321: [KCM] Scale more coarsely with the slider, but more finely with a semi-hidden spinbox

[Roman Gilg]

romangg requested changes to this revision.
romangg added a comment.


  First the situation is different on X11 and Wayland:
  
  - On X11 KScreen sets Qt scale factors and some fonts dpi value through Xft. You can read it up here what was taken pretty much as it was from the old code: https://cgit.kde.org/kscreen.git/tree/kcm/kcm.cpp#n317
  - On Wayland KWin scales in OpenGl the whole image it receives from a client. There should be no artifacts visible with any scale factor, be it 1.1 or π.
  
  Looking at the provided screenshot with artifacts: This must be on X11 and I recognize these artifacts from when I tested different fractional scaling values on X11 months and years ago. Insofar this is no regression and is independent of the KCM rewrite. Which makes sense since the previous ui also offered 0.1 step sizes: https://www.dedoimedo.com/computers/plasma-hd-scaling.html
  
  In regards to Wayland: I don't agree that the 1.25 and 1.75 values are more important than 1.2, 1.3 and respectively 1.7, 1.8 values. That's just because you are used to it from other platforms. And that's a normal first reaction but you won't see a significant size difference between 1.2 and 1.25. Try it with 1.2 and 1.3: even here the difference is minimal.
  
  What I definitely don't want for Wayland: recommending to users to set the size of their UI through the overall scaling value on the one side and on the other side through font size. I know some proficient members of our community know how to do that and think it's ok because it was always like that and it comes naturally to them. But to other users it's difficult or cumbersome to do.
  
  Conclusion: Leave it as it is on Wayland. It works fine there and gives user a way more fine-grained level of control than with .25 steps only. On X11 a separate isolated bug fix to this old known <https://bugs.kde.org/show_bug.cgi?id=373232> problem with artifacts must be proposed.

REPOSITORY
  R104 KScreen

REVISION DETAIL
  https://phabricator.kde.org/D24321

To: ngraham, #vdg, #plasma, romangg
Cc: davidedmundson, ouwerkerk, GB_2, ndavis, cullmann, plasma-devel, LeGast00n, The-Feren-OS-Dev, jraleigh, fbampaloukas, ragreen, ZrenBot, ngraham, alexeymin, himcesjf, lesliezhai, ali-mohamed, jensreuterberg, abetts, sebas, apol, mart
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.kde.org/pipermail/plasma-devel/attachments/20191001/2200dc1e/attachment.html>