Gesture Hooks API

[matt1432]

I am trying to make it possible for another plugin to hook onto the opposite gesture of the workspace gesture.

I had the idea of copying hyprexpo's touchpad gesture on a touchscreen by having hyprgrass emit a hook when dragging the opposite way and then have hyprexpo hook onto it.

I have the hook and listen thing figured out, but the gesture part is very unclear to me.

I can't really tell how to listen to a gesture or even if one is recognized at all. Would love to get some info on that.

Thanks!

Edits:

Check List:

• figure out why info.cancelled is the opposite in hyprexpo
• figure out what the API will expose

[horriblename]

that's genius! I had the idea of using dispatchers to do somewhat the same thing but it was too clunky to use and so I dropped it.

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I think rather than hooking on to the "opposite of workspace gesture" it's easier to provide hooks for a generic "swipe" event (and same for "edge" and others).

for that you can emit the events in handleDragGesture() and handleDragGestureEnd(). A drag basically means the gesture has a clear "start" and "end" point - when a "swipe" is first recognized, handleDragGesture() is called. when the gesture ends, e.g. lifted a finger, handleDragGestureEnd() is called.

not so important to the problem at hand, if handleDragGesture did not do anything (returns false), handleCompletedGesture() will be called in place of the usual "end" event.

---

I'd like to see some way for hook users to tell us if they did anything: if they handled the gesture, we need to block touch events from going to the app window (among other things). for this, EMIT_CANCELLABLE_EVENT might be useful

[matt1432]

So I try having handleDragGesture(), handleDragGestureEnd() and dragGestureUpdate() emit the event but it seems like the workspace swipe takes ownership of any 3 finger swipes if that makes sense.

I try to swipe vertically instead to not trigger the workspace swipe but that does not emit anything during that gesture.

[horriblename]

can you push what you have now?

[matt1432]

It's not much but here you go

[matt1432]

Crashes Hyprland as soon as I do a gesture :(

No crash report in ~/.cache/hyprland

[horriblename]

added some checks, so that workspace swipe doesn't crash

notification now works, but idk what the API should look like yet. i think at the very least we'll need 3 separate hook events for start/update/end and possibly more for each gesture type

edit: also the events should be namespaced under hypgrass: or something

[matt1432]

i think at the very least we'll need 3 separate hook events for start/update/end and possibly more for each gesture type

Yes I was thinking that too.

the events should be namespaced under hypgrass: or something

Yes I agree

[matt1432]

I tried your latest commit and it did work to emit changes for swipes, but the workspace swiping wasn't working, is that normal?

[horriblename]

yea right now the hook just "consumes" the drag event unconditionally

[matt1432]

To make it easier to hook onto, I convert the touch gesture event to a touchpad gesture event. However, I don't really know how to properly convert the delta.

Do you have any ideas @horriblename

[horriblename]

I'm not really sure what unit touchpad swipes are in (and I have no clue where to even dig up this info). you can either:

1. try whatever wizardry I did in updateWorkspaceSwipe()
2. ask vaxry
3. convert to touch events instead, in this case you can use GestureManager::pixelPositionToPercentagePosition() to get the position

try the 1 and 2 first

[horriblename]

I changed my mind, I think it's more helpful to give the exact position of gesture, instead of delta like in SSwipeUpdateEvent,

please use ITouch::SMotionEvent instead

[horriblename]

you can use GestureManager::pixelPositionToPercentagePosition() to get the position

[matt1432]

hmm, I was doing it this way to make it as easy as possible to implement in hyprexpo. Is ITouch::SMotionEvent a Hyprland thing? Edit: it is, I just found it

[matt1432]

@horriblename ITouch::SMotionEvent doesn't have a fingers prop

[matt1432]

@horriblename I finally figured out how to make the hooks compatible with hyprexpo's gesture, which was my original goal.

I had to stick with IPointer::SSwipeUpdateEvent instead of using ITouch::SMotionEvent like you said because it doesn't hold any info on the amount of fingers, and I feel like exposing a delta is better than the position when it comes to a gesture.

What do you think?

[matt1432]

Also, should I be using EMIT_HOOK_EVENT_CANCELLABLE instead of EMIT_HOOK_EVENT?

[horriblename]

Also, should I be using EMIT_HOOK_EVENT_CANCELLABLE instead of EMIT_HOOK_EVENT?

EMIT_HOOK_EVENT is fine. Only the start event needs to check that an event is handled

[horriblename]

I had to stick with IPointer::SSwipeUpdateEvent instead of using ITouch::SMotionEvent like you said because it doesn't hold any info on the amount of fingers

uuh I'll mull it over, but I think if we're exposing a hook API I'd like it to be extensible as possible

[matt1432]

@horriblename I figured out how to add it back, but to make it work with hyprexpo I had to check if info.cancelled was false instead of true

[matt1432]

@horriblename Is this expected? I thought it would've been the opposite no?

[matt1432]

@horriblename Have you given this PR any more thoughts?

I added a small check list in my original message to clarify what I'm hung up on

[horriblename]

Sorry it took this long, I've decided to go ahead with #189 as a stopgap and leave the event hooks for another time.

#189 should cover your use cases (hyprexpo integration), I tested on Hyprspace but please help me test on hyprexpo as well.

I will be generalizing ideas from this PR for a more extensible event hook API.

[horriblename]

If you have no problems with #189 I will close this PR and merge that one

[matt1432]

No worries!

#189 works perfectly for my use case. Just gave it a shot and I'm happy. Go for it

We can leave this PR open and leave it as a draft imo. It's up to you if you wanna continue it or open another one but it's still a good reference for what's possible and whatnot.