the extents rectangle is what you need to know to properly position
a buffer that has been rendered in a surface of the ink rectangle
size. This patch make the placement on par with the placement we had
before without having to over allocate.
This patch also enable placement for vertical rendering. Note that
the halginement, valighment and line-alignment default are set to
the previous default when this property is set. This is for backward
compatibility, you can change the value after setting vertical render.
https://bugzilla.gnome.org/show_bug.cgi?id=728636
The GstVideoOverlayComposition meta coordinates should always be
in stream scale, regardless of the window size downstream. This
way the sink can always scale the composition if the window size
have changed after a buffer (with his meta) was rendered before.
https://bugzilla.gnome.org/show_bug.cgi?id=751157
* cache window size event and update handle ratio
* init width with 1, don't use 0
* don't update overlay when receiving same window size
* receive window size from allocation query
https://bugzilla.gnome.org/show_bug.cgi?id=751157
This makes pipelines with multiple textoverlay elements possible.
The meta data is collected from the upstream textoverlay element,
merged into a new GstVideoOverlayComposition and passed down downstream.
https://bugzilla.gnome.org/show_bug.cgi?id=751157
This prevents the ugly hack where the text_sink pad template
was only added for textoverlay but not for the subclasses.
Also makes this work with the core change that made
subclasses inherit the templates of their parent class.
