Better wayland support

[ksandom]

Background

Currently, wayland support is achieved via VNC, which is not a good user-experience (slow, laggy, and requires manual configuration by the user). This ticket is for getting native wayland support out of the box.

• handWavey's Wayland documentation.

Success

• General
  • [ ] handWavey works in wayland without needing something like VNC/RDP/Synergy etc.
• If configuration is needed for the user to enable it:
  • [ ] Make it as easy as possible to get it going.
  • [ ] Document what configuration is needed.
• Testing: All of the following should still work out of the box:
  • [ ] Windows.
  • [ ] X
  • [ ] MacOS.
• Follow-up
  • [ ] Create a ticket for auto-detecting wayland so that the correct control mechanism can be used.

Necessary functionality of the solution

• Mouse
  • Set mouse location.
  • Set button down.
  • Set button up.
  • Scroll +/-.
• Keyboard
  • Set key down.
  • Set key up.

Possible leads

libei

libei looks like the most promising possibility so far.

SWT

This comment suggests SWT:

SWT already supports Wayland as it uses GDK/GTK.

• Possible implementation? - Doesn't look like it, but maybe.
• org.eclipse.swt.widgets.Display.setCursorLocation(...) - Sounds promising.
  • setCursorLocation.
  • Display documentation.
  • setCursorLocation().

Project Wakefield

Project Wakefield is the recently established OpenJDK initiative to implement native Wayland support within Java.

• Project Wakefield.
• Post announcing it.

OpenJDK developers have acknowledged this will "take years to fully complete and deliver" their native Wayland support.

I don't know how long it will be until keyboard and mouse control will arrive.

uinput

• Stackoverflow post.

OpenJDK 19

As at 2022-03-18; OpenJDK 19 is not able to control the mouse and keyboard via AWT in Walyand.

General discussion

• From a gnome user's perspective.

[ksandom]

SWT Key mappings are listed at static final int [] [] KeyTable = {.

[ksandom]

I've invested a fair bit of time today experimenting with the SWT option. The premise being that it sounds like it already works in Java via SWT. I didn't get it to work, but would love input to solve it.

For now, unless someone can think of a short-term solution, I think waiting for Wakefield is going to be the best bet. libei appears to be the most likely implementation:

Solution: This will probably be implemented be libEI. However, its shipping time(even estimated) is not yet known.

In the mean time, you can check out the handWavey wayland documentation for the latest information about how to work-around the issue.

[ksandom]

libei recently reached 1.0, and even 1.1 a few weeks ago. So it's going to be worth keeping an eye on this. Things could change very quickly now.