Page History

The Wakefield committers may hold off-line discussions from time-to-time. Since these meetings are just for the committers and invited wayland experts, summary minutes will be recorded here as time permits

Online Zoom Meeting 9am PST 10th Feb 2022

Attendees: Kevin, Victor, Olivier, Mario, Aleksandr, Alexey Ushakov, Maxim Kartashev, Sergey, Zdenek, Zhengyu, Dalibor

Discussion:

We went through all of the open issues on the WIki. Aleksandr will update the bugs with the latest status. The suggestion was made to group them by their status into 2 or three groups (unresolved, fix in progress, resolved). For the unresolved issues, they could be prioritized.

1. JDK-8280982 : java.awt.Robot taking screenshots

Needs to be solved by the Portal team. Not limited to Wayland. This is the number one issue in terms of importance. There is a bug filed against Portal in the flatpak project.

We spent some time discussing the current limitations. What we ultimately need is something that only needs to be configured once by an administrator, and will not produce a popup. Another limitation that needs to be overcome is that the current workarounds only capture the entire screen, which is not sufficient for an API that is often used to read small regions (or a single pixel). This will be too slow. Another idea was discussed to throw a security exception in the screen capture API, but that would require a spec change. It's also not what Java2D does on other platforms (e.g., Mac) when the proper permissions haven't been granted.

2. JDK-8280983 : java.awt.Robot emulating keyboard/mouse events

No new information. Solving this using libEI will be best, and will also solve one of the below issues, but there is no time frame as to when we might expect a fix.

Additionally, using libEI should fix following:
JDK-8280995 : X11 compatibility: Robot.mouseMove does not visually move mouse cursor
JDK-8280990 : X11 compatibility: XTest emulated mouse click does not bring window to front.
JDK-8280988 : X11 compatibility: Click on title to request focus test failures

The last of the above two can be worked around by test changes, but using libEI is a better solution.

3. JDK-8280993 X11 compatibility: Popup menu dismiss in X11 compatibility mode.

This one should be fixable.

4. JDK-8280991 X11 compatibility: fake configure event for XRandR emulation

Should already be fixed in latest version

5. JDK-8280985 X11 compatibility: Wayland crash on huge window

Already fixed

6. JDK-8280987 X11 compatibility: crash when mapping a lot of windows

There are two issues here: one is that we are running out of file descriptors, the other is that this will fill up the Wayland buffers. The first is a simple fix (In progress). The second fix in Wayland itself, not XWayland. It's also in progress, but is a complex fix.

7. JDK-8280992 X11 compatibility: Custom colored cursor might be displayed in black and white

Aleksandr will file a bug if he can come up with a simple reproducer

There are additional issues specific to pure Wayland mode that still need to be filed (this needs more discussion).

Online Zoom Meeting 9am PST 27th Jan 2022

Attendees : Olivier, Phil, Kevin, Aleksandr,, Victor, Niels De Graaf, Alexey Ushakov, Jonas, Sergey, Zdenek, Zhengyu

Aleksandr :
Ubuntu 20.04 - some test problems - tests passed on 20.10 and 21.04

XOR
Memory leak tests - need to increase xMax heap
Mouse enter/exit events
Not always clear if Java problem or Wayland

Let's not spend/waste time on older OSes even LTS versions they'll never have
all the support we need anyway.

Working on migrating bugs / issues just documented on internal wiki to JBS using release==internal

Olivier : DnD also fixed in new OSes
Xwayland is not involved in DnD or copy/paste - standard x atoms

Wayland compositor or applications - x app knows nothing about wayland native so it
is the wayland compositor which does the translation
So doing DnD mutter has to map X11 window and use that to translate
Upstream Gnome 42 fix not yet backported to gnome 41 used by Fedora 35 ..

https://gitlab.gnome.org/GNOME/mutter/-/issues/2042
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2259

Can you use latest mutter from main on older OS ? Olivier or Jonas (?) - possible but sounded like a bunch of steps
he will find docs on this
Ed : I think this is the doc meant : https://gitlab.gnome.org/exalm/jhbuild-steps/-/wikis/JHBuild-on-Fedora

Alexey : trying native wayland port rendering using J2D s/w rendering.
Need to fit wayland model to our surface architecture ? Will create a branch in project repo.
Also (AI) will update wiki with info on this

Niels : updated wiki to more clearly describe JDK issues where there are gaps in wayland support

Do AWT Robot docs offer a "way out".
https://docs.oracle.com/en/java/javase/17/docs/api/java.desktop/java/awt/Robot.html

Note that some platforms require special privileges or extensions to access low-level input control. If the current platform configuration does not allow input control, an AWTExceptionwill be thrown when trying to construct Robot objects. For example, X-Window systems will throw the exception if the XTEST 2.2 standard extension is not supported (or not enabled) by the X server.

Applications that use Robot for purposes other than self-testing should handle these error conditions gracefully.

These words are not intended to say you can be conformant - more about advice that you
may need to update settings add packages to mke your desktop supported.
Analogies such as makung sure you have required X11 packages installed and headful support is available.

Zdenek : Fedora rawhide - dev version of Fedora may be a way of getting VERY latest ahead of a Fedora release

...