Gnome flags SFML windows unresponsive.

[tapir]

As discussed on the topic: http://en.sfml-dev.org/forums/index.php?topic=19715
There is a fix #947 that is not working for me. I'm on Arch Linux with Gnome 3.20 and tried the SFML/CSFML from the official repos along with compiling the latest git versions of both of them and the window is still flagged as unresponsive. It doesn't have to be fullscreen as suggested. It always happens.

@binary1248, After a quick chat with a "Clutter" developer on IRC, it's certain that this only happens if the application doesn't respond properly to _NET_WM_PING. I asked specifically if anything else can cause this and the answer was no. I don't know if that helps but that's the only information I got.

[tapir]

Something I've noticed today is that when there is another opengl window open (I'm playing Axiom Verge to be clear. It uses SDL2 through FNA monogame fork) I don't get this message. Go figure :)

EDIT: As a side note SDL2 has a window hint that disable _NET_WM_PING completely. It might be a good option actually: https://wiki.libsdl.org/SDL_HINT_VIDEO_X11_NET_WM_PING

EDIT2: After a little further investigation to the source code of both SDL2 and SFML, I've noticed that apart from sending a ping while event dispatching, SDL also sends a ping inside its window creating function: https://github.com/spurious/SDL-mirror/blob/master/src/video/x11/SDL_x11window.c#L587
That might just be the difference since this issue only happens at the start of the program and never again.

[bsaleil]

Hi,
Same bug here using Arch Linux with Gnome 3.20.
I don't know if it helps (and if it's related) but I noticed that the window manager logs the following message to session logs:
Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0xa0000c (SFML windo)

[buchwj]

Hello,
I've observed the same issue on Fedora 22 with Gnome 3.16 using the distro-provided SFML packages. I also cloned this repository and built the latest version, but the same error appears.

Edit: It seems that this issue does not occur on the same computer if KDE 5.19.0 is used instead of Gnome. If I switch back to Gnome, the issue reappears.

[tapir]

Hi,
Same bug here using Arch Linux with Gnome 3.20.
I don't know if it helps (and if it's related) but I noticed that the window manager logs the following message to session logs:
Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0xa0000c (SFML windo)

This is promising. Any news on this?

[AoifeHughes]

I can confirm I have the same issue on Ubuntu 16.04 with Gnome 3.18

Another issue that I've had is once this is triggered any input via SFML is activated and will not stop. I.e. if I was moving a character to the right, when the unresponsive error appears then I would not be able to stop moving to the right.

[ghost]

I have the same issue on Antergos running Gnome 3.20.2
Doesn't matter if I'm fullscreen or windowed.

Is this as simple as fixing the timeout length on the event?

[binary1248]

Try out the bugfix/xlib branch and see if it fixes the problem.

[eXpl0it3r]

@tapir, @SirSharpest, @bsaleil, @buchwj can you try the bugfix/xlib branch? CI snapshots can be found here.

[tapir]

@eXpl0it3r for me it looks like its fixed. thank you

[bsaleil]

Thanks for trying to fix that @binary1248.
Today I first tried to reproduce the bug using an updated system (Antergos) with latest SFML version (without using xlib branch).
Strange thing is that I'm not able to reproduce the bug using my laptop. I then switched to my desktop computer (still Antergos & Gnome) and I'm still not able to reproduce it.
The fact is that the bug was particularly hard to reproduce for me, so I don't really know if it's fixed or just not showing.

[AoifeHughes]

Yep that's sorted.

What was the issue out of curiosity?

[tapir]

From what I understand they completely switched from XCB to Xlib. I'm ok with it since XCB never lived up to its potential and it doesn't have to anymore since we will have Wayland in the near future.

[Ostefanini]

Okay, so to fix it we have to use a special branch or just use 2.4 ? because in my school everyone use gnome and SFML and everyone have this issue (we are 500+)

[eXpl0it3r]

@Ostefanini You can test the bugfix/xlib branch and may fix this issue.

[eXpl0it3r]

Should be fixed through #1138 in 1dc3db0.

[Ostefanini]

I am very interested to use this fix, how to ?

[eXpl0it3r]

You can compile the 2.4.x branch.

[tapir]

Can we maybe get a 2.4.1 release so that distros pick it up?

[Ostefanini]

Okay, as ever cmake && make && sudo make install ?

[MarioLiebisch]

@Ostefanini: Essentially, yes, just don't forget to switch branch first.

Switch to the 2.4.x branch:

git checkout 2.4.x

Build:

cmake . && cmake --build .

Install:

sudo cmake --build . --target install

@tapir: It's planned, but there are a few other open issues for 2.4.1.

[Ostefanini]

Yeah yeah, for sure it was just about the compile part. Love cmake, and love sfml.