Bug 439925

Summary: More default global touchscreen gestures
Product: [Plasma] kwin Reporter: Thiago Sueto <herzenschein>
Component: GesturesAssignee: KWin default assignee <kwin-bugs-null>
Status: CONFIRMED ---    
Severity: wishlist CC: el, nate, qydwhotmail
Priority: NOR Keywords: usability
Version: unspecified   
Target Milestone: ---   
Platform: Other   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=401479
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Thiago Sueto 2021-07-16 00:19:50 UTC 
The wayland session of GNOME 40 got a major uplift to touch gestures compared to GNOME 3.38. Here's a brief chat I had with Zamundaa mentioning this: https://www.reddit.com/r/kde/comments/oe2t8k/multitouch_touchscreen_gesture_support_in_kde/h449ahm?utm_source=share&utm_medium=web2x&context=3

The changes to GNOME 40 were:

* Drag window with one finger to corner : window snapping
* Swipe to upper left corner : toggle overview
* Swipe from the upper edge down on an empty space in the panel : get control and drag current window without using titlebar or headerbar
* Swipe from the upper edge down on top of a top panel widget (like calendar, tray or a11y): open widget even if they're not visible (e.g. with zoom)
* Swipe 3 or more fingers left or right : switch virtual desktops
* Swipe 3 or more fingers up : open virtual desktops activities overview
* Swipe 3 or more fingers left or right while in overview : switch virtual desktops
* Swipe up again : open app drawer
* Swipe 1 or more fingers while on app drawer : switch pages
* Swipe app in virtual desktop thumbnail : pull it to different virtual desktop

In other words, it was an amazing release for touchscreen support, and it fits their desktop well.

As can be seen here, Plasma is already able to detect at least ten different fingers (even if it starts lagging at that point), as shown by the Touch Points desktop effect: https://www.reddit.com/r/kde/comments/od9bu6/unique_desktop_effect_for_touch_screens_touch/

Yet there's practically no touchscreen gestures. There was no report to track this either.

Having touchscreen gestures at some point in the future would improve the Plasma experience IMO.
This would also require quite some thought put into it, because global Plasma touchscreen gestures should:

1. Take into account the uniqueness of Plasma (it isn't one-axis-workspace centered like GNOME)
2. Take into account Plasma mobile (like Zamundaa mentions above)
3. Not break applications that also use touch input (Gwenview, Koko and Pix all have pinch to zoom for instance)

Using 3 or more fingers like GNOME did looks like a good idea.
Comment 1 Nate Graham 2021-08-03 19:22:02 UTC 
We already have a few on Wayland, the problem is that they don't follow your fingers; see Bug 401479.

I agree that it's important for us to make big improvements in this area, though.
Comment 2 Bug Janitor Service 2021-11-08 16:06:50 UTC 
A possibly relevant merge request was started @ https://invent.kde.org/plasma/kwin/-/merge_requests/1617
Comment 3 Zamundaaa 2022-03-27 21:45:26 UTC 
Git commit 8914a6c50e1d1fba919b436eb42471421362d838 by Xaver Hugl.
Committed on 27/03/2022 at 17:09.
Pushed by ericedlund into branch 'master'.

add global touchscreen gestures

Swipe with three fingers
- left to switch to the previous virtual desktop
- right to switch to the next virtual desktop
- up and down to toggle the overview

M  +4    -0    autotests/test_virtual_desktops.cpp
M  +5    -0    src/effects.cpp
M  +1    -0    src/effects.h
M  +2    -0    src/effects/overview/overvieweffect.cpp
M  +43   -20   src/globalshortcuts.cpp
M  +18   -8    src/globalshortcuts.h
M  +123  -5    src/input.cpp
M  +3    -0    src/input.h
M  +10   -0    src/libkwineffects/kwineffects.h
M  +1    -1    src/touch_input.cpp
M  +3    -0    src/virtualdesktops.cpp

https://invent.kde.org/plasma/kwin/commit/8914a6c50e1d1fba919b436eb42471421362d838
Comment 4 Ellie 2024-07-06 18:02:46 UTC 
I think it would be desirable if whatever is configured in "Input & Output" > "Mouse & Touchpad" > "Screen Edges" > respective corners/edges (like the top left hot corner that triggers the overview by default) would also work via touch. I tried to see the overview like I do with the mouse by dragging my finger into the corner and it doesn't feel right that it doesn't work. For consistency, I think supporting that just like it's configured for the mouse would make the most sense.

Otherwise I think KDE's/plasma's biggest touch UX problems are that the keyboard hiding isn't working right ( https://github.com/maliit/keyboard/issues/223) and that it comes up all the time when it shouldn't (e.g. https://bugs.kde.org/show_bug.cgi?id=489672 ). Phosh with a GNOME desktop doesn't have any of those issues. I think global gestures are kind of a secondary concern if the basic on-screen keyboard doesn't work right.

(Sorry that I barged into this bug report, but I've been trying to use KDE on a tablet for a few days now and evaluating the experience. It's a great desktop, but it doesn't work very well in that setting right now.)