Prior to 5.21 we had "Force font DPI" option. This option, at least on my 4K screen, would work like Global Scaling with the only difference being that global scaling option seems to "lower resolution" or... Try to "make pixels bigger" (Sorry I don't know what definitions should be used). I don't know if this behaviour was a bug unique to my system or not. How to confirm: 1. Use a 4K screen (or simply a high resolution one) and a system with Plasma <5.21 2. Try setting global scaling to 150-200% and also try setting "Force don't DPI" option ~120 Do you feel any difference? Arch Linux, plasma 5.20-5.21
So there are a few things here: 1. Yeah, we removed the Force Fonts DPI setting from the fonts KCM on the logic that it was redundant with simply being able to change the fonts. Maybe that was a bad idea. 2. Because Wayland only does integer scaling, setting 150% scale will internally do 200% scale and then scale down the resulting image, which does cause some blurriness 3. 200% scale does not result in any downscaling at all, so it should be nice and sharp--exactly as when using the old Force Font DPI setting Can you confirm that 200% scale produces an image that's as sharp as using the old force fonts DPI setting did? It should, and it does for me; if it doesn't for you, that's a bug that needs to be investigated. I suspect that this will ultimately lead to multiple bug reports, but let's start with one thing at a time. :)
I will try to answer all those. But I cannot guarantee when that happens. (Not because I'm lazy)
No worries. :)
Created attachment 135829 [details] 200% Scaling Here is the image with Global Scaling set to 200%. It seems like it has affected only apps other than those of KDE (Dolphin, Konsole etc). If you zoom on this image you might see that everything looks kind of blurry inside firefox.
Created attachment 135830 [details] 150% Scaling And here is with 150%. I think that they all downgrade. Here it seems like it downgrades less. You can see the panel though stays "clean". I also checked the monitor: it's an LG 32UK550/UL 500 model 3840x2160/60Hz Physical Size: ~39x69 cm (screen only)
I also opened inkscape. Seems like everything has been scaled without loss of quality. Also notice from the screenshots that plasma's mouse has been affected badly.
Blurriness at 200% scale in Firefox on Wayland is due to Firefox not using Wayland natively, but rather XWayland. XWayland apps suffer from this, sadly (known bug). If you run with `MOZ_ENABLE_WAYLAND=1` and restart Firefox, does it get better?
Where am I supposed to write this line? I typed it in terminal and seems like, after restarting, nothing changed.
You can do this: `MOZ_ENABLE_WAYLAND=1 firefox`
The command seemed to make Firefox look neater, probably as it should be in this screen, but it seems like there were a lot of screen tearings (or some similar bugs) and plasma couldn't handle it, so it seems like I was logged into a new session automatically and a report said that konsole crashed.
Yeah, so what's going on there is that Firefox looks correct when using Wayland native mode. When in XWayland mode, it's downscaled due to the aforementioned problem with scaling on XWayland. So maybe we really do need to bring back the force Font DPI spinbox until Wayland gains non-integer scaling without downscaling, and XWayland gains the ability to do any kind of scaling without upscaling. :(
(In reply to Nate Graham from comment #1) > So there are a few things here: > > 1. Yeah, we removed the Force Fonts DPI setting from the fonts KCM on the > logic that it was redundant with simply being able to change the fonts. > Maybe that was a bad idea. > > 2. Because Wayland only does integer scaling, setting 150% scale will > internally do 200% scale and then scale down the resulting image, which does > cause some blurriness > > 3. 200% scale does not result in any downscaling at all, so it should be > nice and sharp--exactly as when using the old Force Font DPI setting > > > Can you confirm that 200% scale produces an image that's as sharp as using > the old force fonts DPI setting did? It should, and it does for me; if it > doesn't for you, that's a bug that needs to be investigated. > > I suspect that this will ultimately lead to multiple bug reports, but let's > start with one thing at a time. :) Yes please restore Force Fonts DPI! Please...Please...Please
So basically you want to work around 433269.
If that's more convenient for everyone.. then yes.
I came here to make this exact same bug. The problem is when dealing with applications that actually use pixel based images I lose definition. If I set my scale to 175% on a 4k monitor, then watch a 4k movie in MPV, it gets scaled down and I lose definition. If I open a 4k image in a web browser or image editing tool the image is scaled down to the "Global Scale" and I cannot see the full image. Some applications (GIMP) for example, have very blurry fonts. The old DPI approach worked very well. Using the "Scale" option, other that a few desktop UI elements that understand it, I may as well run my screen at 1080p. The font DPI approach worked a lot better because one pixel was always one pixel.
Sorry for the double post but here's a way to test it and demonstrate the issue 1. Take a screenshot using spectacle or another tool at native resolution and save it lossless (png) 2. Turn on display scaling 3. Open the screenshot in mpv: mpv screenshot-001.png --pause Double click to full screen it and you can see that it's not as sharp as the original. You can also press `i` to bring up the stats and confirm that "Window scale" is not 1.0. This could probably be fixed by MPV (and every other application affected...) but the previous DPI approach worked fine without needing to fix everything that uses images.
A possibly relevant merge request was started @ https://invent.kde.org/plasma/plasma-workspace/-/merge_requests/669
Why KDE/Wayland cannot have scaling without lowering resolution like in KDE/X11? Scaling on X11 is mostly works and similar to windows.
https://gitlab.freedesktop.org/wayland/wayland-protocols/-/issues/34
Git commit 62842ac6fd5571394e38360b345a7ad3a1187273 by Nate Graham. Committed on 07/03/2021 at 00:30. Pushed by ngraham into branch 'master'. Re-add Force Font DPI spinbox on Wayland People are using this feature to work around Wayland's terrible fractional scaling implementation that makes everything super blurry. I can't in good conscience tell them to use it anyway because it really does look so bad. :( See https://bugs.kde.org/show_bug.cgi?id=433269. This reverts commit 65defddee95db6738d5e2c80f6c7b373fde451a1 This reverts commit 40afa58ab9bf0d0808edb891f9cd855316a82411 FIXED-IN: 5.21.2 M +3 -2 kcms/fonts/fonts.cpp M +1 -0 kcms/fonts/fontsaasettings.cpp M +4 -0 kcms/fonts/fontsaasettingsbase.kcfg M +14 -3 kcms/fonts/package/contents/ui/main.qml M +6 -1 kcms/krdb/krdb.cpp M +8 -0 startkde/startplasma-wayland.cpp https://invent.kde.org/plasma/plasma-workspace/commit/62842ac6fd5571394e38360b345a7ad3a1187273
Git commit 1278ebee2a6e72de2b3600d2baa61e57378f3d9f by Nate Graham. Committed on 07/03/2021 at 00:32. Pushed by ngraham into branch 'Plasma/5.21'. Re-add Force Font DPI spinbox on Wayland People are using this feature to work around Wayland's terrible fractional scaling implementation that makes everything super blurry. I can't in good conscience tell them to use it anyway because it really does look so bad. :( See https://bugs.kde.org/show_bug.cgi?id=433269. This reverts commit 65defddee95db6738d5e2c80f6c7b373fde451a1 This reverts commit 40afa58ab9bf0d0808edb891f9cd855316a82411 FIXED-IN: 5.21.2 (cherry picked from commit 62842ac6fd5571394e38360b345a7ad3a1187273) M +3 -2 kcms/fonts/fonts.cpp M +1 -0 kcms/fonts/fontsaasettings.cpp M +4 -0 kcms/fonts/fontsaasettingsbase.kcfg M +14 -3 kcms/fonts/package/contents/ui/main.qml M +6 -1 kcms/krdb/krdb.cpp M +8 -0 startkde/startplasma-wayland.cpp https://invent.kde.org/plasma/plasma-workspace/commit/1278ebee2a6e72de2b3600d2baa61e57378f3d9f