bug: does not work with touchscreen or stylus

[SnoutBug]

Describe the bug/issue
Can't drag & drop windows using the touchscreen or stylus, the highlighted area is always at the location the mouse pointer would be.

To Reproduce
Steps to reproduce the behavior:

1. Use touchscreen or stylus to drag & drop windows

Expected behavior
Same behavior as with mouse.

Version Information

1. Arch 5.19.13
2. Forge version 57
3. GS 43
4. Wayland

Monitor Setup

1. 1 x 1080p
2. Rotateable

Additional context
I'm using a ThinkPad L13 Yoga

[jmmaranan]

Thanks for the report. Don't have a touchscreen to test/fix this on.

[SnoutBug]

I'm guessing the solution would be something similar to this, this might be useful for anyone with the means to test these changes and enough experience to implement something like this. I will try my best, but I'm not certain that I will achieve any meaningful results.

[jmmaranan]

Hi @SnoutBug did you notice anything on the logs? Any errors/stack traces? What other extensions do you have?

My thoughts are that the touchscreen hardware already acts like a mouse.

If the extension is disabled, are you able to drag drop windows? Also, helpful would be a video of the issue.

[SnoutBug]

did you notice anything on the logs?

No I'm not aware of anything when testing with dbus-run-session -- gnome-shell --nested --wayland if you can tell me where to find proper logs, I will be happy to share them with you.

If the extension is disabled, are you able to drag drop windows? Also, helpful would be a video of the issue.

Yes, I am able to drag the window regardless.

My thoughts are that the touchscreen hardware already acts like a mouse.

On Wayland it seems to be possible to have multiple cursors, so the touchscreen has it's own cursor, so does the stylus and the mouse. global.get_pointer() only returns the mouse pointer and not the touchscreen position. At least this is how I understood it. This also explains the behavior seen in the video below:

Screencast.from.2022-10-14.09-23-53.webm

In this video I'm dragging the window with the touchscreen and moving the cursor with my mouse (touchpad)

[jmmaranan]

Ok, that's helpful. I'll point you to the part of the code that does the preview sometime this week if you want to try and fix it.

[SnoutBug]

Sure, that would be wonderful!

[jmmaranan]

Hi @SnoutBug - the grab logic starts here to setup the selection of target windows going underneath the dragged window: https://github.com/jmmaranan/forge/blob/4e5ad106cb2222426a47ec8009fb421d857502a0/window.js#L164

The core is this function - which contains the resizing and moving (dragging) handlers: https://github.com/jmmaranan/forge/blob/4e5ad106cb2222426a47ec8009fb421d857502a0/window.js#L1541

Though I think as you mentioned earlier the global.get_pointer() is only where the cursor is and should instead use a different reference point when touchscreen or stylus. You might want to start here and change where the pointerCoord value comes from: https://github.com/jmmaranan/forge/blob/4e5ad106cb2222426a47ec8009fb421d857502a0/window.js#L2018