Libinput, the input handling library for Wayland, does not automatically detect the transition between a single finger touch and a two-finger scroll gesture. This is due to the nature of how touch events are handled and interpreted by libinput.
I cannot use the two-finger scroll unless I either completely stop all single-finger movement first, then carefully put down the second finger, then two-finger scroll, or I can completely remove both fingers and then place the two fingers down together and now I can two-finger scroll, but i can not just raise the second finger to go back to moving the cursor.
I cannot move the cursor, put down the second finger and scroll a bit, then lift the second finger and be back to moving the cursor.
Itâs just about impossible/unusable in the way I describe. So I just wondered if there was any way to remedy this before I start looking into all the other problems with Wayland?
On X11 i use the synaptic driver and it works just fine.
I have to use a trackpad with my desktop because of the way its setup.
I have used x11 for years and synaptic works just fine.
I now have to change to wayland but i can find how to sort the trackpad out.
First thing is it cant detect the transition between a single finger cursor moment and a two finger scroll.
If im moving the cursor around the screen with a single finger i need to be able to just put down the second finger while im still moving the first finger and have the system recognize that it should now be two finger scrolling. It should also do the same in reverse (lifting second finger up to be back to cursor movement).
Secondly, I need the coasting on all windows not just firefox.
I have tried to work without these basic functions that exist and are fine in synaptic, and its a case of computer nearly out the window from me fighting with it at every moment.
Why do you HAVE to change to Wayland? KDE Plasma still supports X11, and their lead developer Nate Graham said in September 2024 that there are no concrete plans to stop supporting X11.
If there are any settings you can change, they would be in KDE System Settings under âMouse and Touchpadâ while using a Wayland session.
FWIW, I just tried what you described, and it worked perfectly for me on Wayland. I moved the cursor with one finger, put down a second finger and started scrolling, then lifted the second finger and started moving the cursor around again.
Also, what do you mean by âcoasting on all windows not just firefoxâ?
They mean inertial scrolling.
Like you two finger swipe up quickly, release, and it keeps scrolling.
It simply does not work everywhere with libinput as the API is such a way that the application(s) themselves must implement it. As opposed to the hacky old way where it was basically some math of events being duplicated.
As such it exists in some applications, like firefox, but not all. https://wiki.archlinux.org/title/Libinput#Inertial_scrolling_does_not_work_in_KDE
Thank you for answering for me @cscs , iv been very busy with multi boot system, with testing of old/new manjaroâs / and other disrtros, all alongside each other. It has been one confusing day of grub etc but i dont want to destroy anything just yet. Iâm now looking at at lot although i donât fancy learning a whole new set of package managers and god only knows what else, i mean iv been tinkering with Manjaro for 5 years or so and nothing else (prob do me good in the end though).
Hi, can you actually do this on wayland?
i dont just mean put down the second finger after the single finger has completely stopped moving, i mean continuous movement of the first finger and while its in moment put down the second finger to start scrolling?
If you can do this then there must be a way for me to do it to. But how?
As explained , the technical wikis and manuals refer to it as âcoastingâ, as in âcosting alongâ.
yea im sure it does, its prob just certain peoples hardware, maybe the video out chipsets or the monitor itself, who knows but its unusable for in such a state and iv only just brought this system not long ago. Point being that it was as stable as a rock before Christmas. Meh, pass. There is a bug report out though as iv mentioned elsewhere. EDIT here: 497204 â Plasmashell crashes in qDeleteAll<QList<QSGCurveAbstractNode*> on monitor wake
But yea im certainly interested in this trackpad ability you describe and how yours is different to mine.
Wont even start on the clipboard manager that i use continuously, i think copyq has problems on wayland and maybe others do to, not had a chance to get that far yet.
Not really. While the exact phrase used at one point was rather variable, like most new things, it eventually got more standardized.
The only thing âtechnicalâ referring to âcoastingâ that I can find is the synaptics option.
And hence, archwiki pages referring to synaptics configuration likewise contain the phrase.
We may also recognize that synaptics is unmaintained legacy software so it hardly reflects modern standards.
The technical term is inertial scrolling as I already alluded to.
This term can be found, among other locations, on the wikipedia page for âScrollingâ;
Technically correct, â The best kind of correct â
Well iv got several trackpads (these are usb pads not laptop) and they just do not work like that for any of them. Iâm all up for suggestions. (they all do when setup right with synaptic though).
Well, Iâve read/scanned your skinny and itâs all Chinese to me. I donât see anything that jumps out as a way to enable it to see the transition from one finger to two any better, so i wouldnât know where to start. Thx for the info though.
There is no special configuration file to use like /etc/libinput.conf.
The only options are those presented by your Desktop Environments settings.
Or some of them can be achieved by using udev rules.
The only other option is this AUR package to provide any settings your DE does not.
I dont really know why any of that would need to be translated into roughly the same sentences with different words - everything Iâve written says pretty much the same thing - but I am unsure of how else to make it any more digestible.
~There is no setting for what you describe that I know of, its just how it works already.~
Maybe, possibly, its bundled in some other setting like tapping or scrolling so my options were shared in case that was true. It could also be that some other software is interceding to disallow the normal behavior. Unsure. I can only attest to it working as described and there being no explicit option to enable or disable the behavior.
thx, i can only say what is happening on a clean new installation with all of my touchpads/trackpads on wayland. If you are moving a cursor and you put a second finger down it does not scroll nor does it continue to move the cursor, the cursor just stops and thatâs it, until you lift a or both fingers off the pad.
Yes, I did exactly what you described on Plasma Wayland with the trackpad built into my laptop. Perhaps things work differently for the USB trackpads that you use.
Technically correct, â The best kind of correct â 
