| Summary: | Allow lesser than 1 scale factor | ||
|---|---|---|---|
| Product: | [Plasma] KScreen | Reporter: | Filipe Azevedo <pasnox> |
| Component: | kcm | Assignee: | Sebastian Kügler <sebas> |
| Status: | RESOLVED INTENTIONAL | ||
| Severity: | wishlist | CC: | kde, nate |
| Priority: | NOR | ||
| Version First Reported In: | 5.14.3 | ||
| Target Milestone: | --- | ||
| Platform: | Other | ||
| OS: | Linux | ||
| Latest Commit: | Version Fixed/Implemented In: | ||
| Sentry Crash Report: | |||
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Description
Filipe Azevedo
2018-11-18 20:39:57 UTC
A scale factor of 2x should make a 2880x1800 effectively into a very sharp and crisp 1440x900 screen. Why can't you just use a 2x scale factor? What am I missing here? Retina screens in kscreen kcm for X11 does not have the possibility to change the screen resolution. The scale factor.... is an upscale factor, not a downscale factor. So moving the scale factor to x2 just make it twice bigger while i want to reduce it (downscale). Wayland allows per-screen scale factors, there you can use 2x on your Retina laptop and 1x on the external screen. Indeed, wayland is much better in this area, still wayland is not stable at all with my mac and nouveau driver and lead to frequent freeze. Also, using scale factor as a way to report the screen scale factor is plain wrong for user and lead to miss understood. A scale factor is something that would scale a given size. Wayland and X11 scale usage is totally inconsistent, and it's really wrong wrong wrong for the user switching wayland/x11. X11 use it as an upscale feature while wayland use it to reduce the screen hardware size by the factor. If you have a Mac retina screen, that means that when running at native resolution, everything will be too small. You want things to be *bigger*, which a 2x scale factor accomplishes. Using a 0.5x scale factor (for example) would make the already tiny screen content even smaller, which makes no sense. As Kai mentioned, on Wayland you can use per-screen scale factors, which should resolve the problem. Does everything work properly when you use the Wayland session and set a 2x scale factor for your Retina screen and a 1x scale factor for the external screen and DON'T use your xrandr hack with the script (which I guess wouldn't work on Wayland anyway)? Dear Bug Submitter, This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information as soon as possible and set the bug status as REPORTED. Due to regular bug tracker maintenance, if the bug is still in NEEDSINFO status with no change in 30 days the bug will be closed as RESOLVED > WORKSFORME due to lack of needed information. For more information about our bug triaging procedures please read the wiki located here: https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging If you have already provided the requested information, please mark the bug as REPORTED so that the KDE team knows that the bug is ready to be confirmed. Thank you for helping us make KDE software even better for everyone! Let recap things, because i have the feeling i did not emphasized enough on the issue being *dual* screens with internal screen being a retina screen and the external one a full hd screen non retina, under X11. If you have only a retina screen - the kcm scale feature just work, but break as soon as you add another screen, simply because it's an all screens scale. To be honest this *global* scale feature is useless, i still can't understand how it was accepted. Note that I do know that wayland can do per screen scale factors, but i don't care because wayland/nouveau is all but stable on a mac machine. I did disable my script (command is: xrandr --output DP-2 --scale .5x.5 --output HDMI-0 --pos 1440x0) which is basically downscaling the screen picture of the retina screen half its size and move the other screen near it so that it make a contiguous plan. This script is executed by the user session autostart kcm - and it just do the job. The *only* draw back is that the downscale has a lower rendering quality, but clearly acceptable for what it fix. So, i the initial request title is somehow wrong - because in reality we may not speak about the same feature. kscreen kcm seems to apply a xorg screen scale feature, while i do speak about xrandr scale property. I have no idea what kscreen try to do behind the scene (but i really would like to know the details, even pointing the exact code applying the changes), but what i need is an out of the box working solution for a retina mac with external screens plugged. Hope it help understanding correctly the issue. We just restored the ability to set < 96 DPI values in the Fonts KCM, so I guess this seems reasonable too. Try: QT_SCALE_FACTOR=0.75 kcalc On my system (Qt 5.12.0), it does not work satisfactorily. Oh gosh, you're right. In fact, every app I try it with is uselessly muddled and unusable, including 3rd-party non-KDE Qt apps. Doesn't look like we can do this until Qt improves support here. :( The Qt env var to scale screens is useless, because it would have to be applied correctly before even starting the plasma desktop (in reality it would be this app to change the scale) so that its inheriting apps render correctly. The only current solution is xrandr scale feature using .5 scale factor (hence my allow less than 1 scale factor, but in the end they are not the same scale factors). Any chance this being used instead of a global xorg things that serve nothing but create more problems ? Xrandr can do per screen scaling, and might be a better solution until wayland impose itself. There is nothing to wait for Qt because there is no issue to fix in it. |