sdl_glimp: set APPID as WMCLASS on Linux

[illwieckz]

Let X11 and Wayland desktops (Linux, FreeBSD…) display the game name on the game windows instead of the engine binary name. This also makes possible to display the correct icon if that WMCLASS is also set in the net.unvanquished.Unvanquished.desktop file.

[illwieckz]

To get the icon properly displayed we need to update the desktop file installed by the updater, but this is enough to make the game name properly displayed.

[illwieckz]

I also added the SDL_HINT_APP_ID variable, which is used by SDL3 instead of SDL_VIDEO_X11_WMCLASS and SDL_VIDEO_WAYLAND_WMCLASS from SDL2. We're not using SDL3 yet but this way we are ready. Also some people are already using the SDL2 compatibility layer of SDL3 and maybe the APPID is already supported this way.

See: libsdl-org/SDL@2f75596

[slipher]

I wondered which desktops do this. Apparently GNOME is one.

[illwieckz]

Our problem is that the desktop file is starting the updater binary that then launches the daemon binary… So we need some way to let the desktop knows what is what.

It would be good to find a similar mechanism to implement in the updater too. On my end GNOME fails to associate the Unvanquished launcher icon with both the updater window and the engine windows.

[slipher]

Our problem is that the desktop file is starting the updater binary that then launches the daemon binary… So we need some way to let the desktop knows what is what.

Why is this a problem? According to the SO link, GNOME doesn't know or care which desktop file was used to launch the program. The updater desktop file already uses the name "Unvanquished" and the standard Unvanquished icon. Supposing we associate the updater's desktop file with both applications, the only nicety we would lack is the updater would use the standard icon rather than the updater variant with the little arrows.

[slipher]

These should also be PRODUCT_APPID

[illwieckz]

Oh lol, I did not noticed that the default WMCLASS was the APPID, which makes sense btw.

So now all those hints are using PRODUCT_APPID.

This has the side effect of displaying net.unvanquished.Unvanquished in the taskbar if there is no XDG icon though.

[illwieckz]

This has the side effect of displaying net.unvanquished.Unvanquished in the taskbar if there is no XDG icon though.

This is probably a bug of the GNOME extension I use. The window name is set properly by SDL_CreateWindow() and is properly displayed in the window title bar and in the GNOME Shell application overview.

[slipher]

LGTM. Setting SDL_VIDEO_WAYLAND_WMCLASS works for me for setting the icon while using Wayland with KDE.

[illwieckz]

I only reworded the comment a bit.