Use waylandsink in Wayland sessions for GStreamer 1.16+

[Integral-Tech]

Use waylandsink instead of xvimagesink/ximagesink in Wayland sessions.

[fduncanh]

Thanks, we will look into this. Does autovideosink fail to choose waylandsink when appropriate?

[Integral-Tech]

@fduncanh Yes, XWayland is used by default in Wayland sessions.

[fduncanh]

Has waylandsink been improving with time? Would it be appropriate to only make waylandsink the default choice if gstreamer version is sufficiently new?

[Integral-Tech]

@fduncanh Now waylandsink is selected by default for GStreamer 1.16+ :)

[fduncanh]

@Integral-Tech

Now waylandsink is selected by default for GStreamer 1.16+ :)

does this mean the fix is not actually needed?

If needed, this code below should be done in renderers/video_renderer.c (video_renderer_init) and renderers/x_display_fix.h

   guint major, minor, micro, nano;


    gst_version (&major, &minor, &micro, &nano);


    if (major >= 1 && minor >= 16) {


    	const char *xdg_session_type = getenv("XDG_SESSION_TYPE");


    	if (xdg_session_type && strcmp(xdg_session_type, "wayland") == 0) {


            videosink = "waylandsink";


    	}


    }

[Integral-Tech]

does this mean the fix is not actually needed?

@fduncanh No, I mean in my fix waylandsink is only selected for GStreamer 1.16+ on Wayland sessions.

[fduncanh]

OK

so the issue is with autovideosink on a system with X11 support that chooses xvimagesink or ximagesink when wayland is active, on gstreamer >= 1.16.

XDG_SESSION_TYPE will only be set on a system with X11 so it can be tested for inside #ifdef X11_DISPLAY_FIX ... #endif

where does the gstreamer > =1.16 come from? is this when gstreamer started to have waylandsink?

[fduncanh]

This is really a gstreamer autovideosink issue, though... maybe there is a gstreamer fix?
it could also be handled with a warning message suggesting the user uses -vs waylandsink ? (instead of overriding autovideosink)

this would test for Wayland when x[v]imagesink is selected and issue a terminal message if wayland is being used.