Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

This ensures the display name provided to gst_vaapi_display_*_new()
maps to the system defaults, instead of forcing "" that could be different
from the current DISPLAY name.

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

This ensures a VA display is ready by the time upstream elements request
for it.

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

This also fixes extra structures, beyond the one at index 0, to hold
the right additional values.

gst_vaapi_surface_set_subpictures_from_composition().

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

Otherwise, the decoder would always create its own X display instead
of probing it from the downstream element, which is not reliable.
e.g. DISPLAY is not :0 or when running on Wayland.
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

With the new video/x-surface abstraction, we can't rely on having a VA
specific sink downstream. Also, there was no particular reason to do that.
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

This new interface allows for upstream and downstream display sharing
that works in both static and dynamic pipelines.
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>