Posting any message to parent seems to be pointless. That might break
parent window.
Regardless of the posting, parent window can catch mouse event
and also any keyboard events will be handled by parent window by default.
Fixes: https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/issues/634
Using a single condition variable for synchronization across all GL
messages is very slow on Windows and uses up to 20% CPU usage in some
workloads due to lock contention and false broadcasts.
Using per-message event handles reduces the CPU usage to negligible
amounts despite having to allocate a new event handle for each
message.
No-one's using/depending on it (it would have criticalled and not worked)
and it's causing more problems than it's solving. Store the GMainContext
in the public struct instead for subclasses to optionally use instead of
relying on the push/pop state to be correct.
https://bugzilla.gnome.org/show_bug.cgi?id=775970
- glimagesink needs to be able to resize the viewport on aspect ratio
changes resulting from either caps changes or 3d output mode changes.
- Performing a glViewport outside the GstGLWindow::resize callback
will not have the winsys' stack of viewports required to correctly
place the output frame.
Provide a function to request a resize on the next draw event from the
winsys.
Also track size changes inside the base GstGLWindow class rather
than in each subclass.
https://bugzilla.gnome.org/show_bug.cgi?id=755111
When called from gst_gl_window_win32_close(), internal window
could not exist, and if it does it's going to be destroyed just
after that anyway. Also it causes window_proc() to be called
and crash because it gets a NULL context.
When called from gst_gl_window_win32_set_window_handle() we are
going to set another parent anyway, and it's probably better to
reparent directly instead of passing by a NULL parent which could
cause the internal window to popup briefly.
https://bugzilla.gnome.org/show_bug.cgi?id=749601
gst_gl_context_finalize() is calling gst_gl_window_win32_quit()
which was posting a message. But then window_proc takes window's
context and get a NULL.
Now that we've got a GMainLoop we can do like other backends and
simply call g_main_loop_quit().
This also remove duplicated code to release the parent window and
potential crash there because parent_proc could be NULL if we never
created the internal window. That could happen for example if setting
state to READY then setting a window_handle, and go back to NULL state.
https://bugzilla.gnome.org/show_bug.cgi?id=749601
gst_gl_window_win32_send_message_async() could be called before the
internal window is created so we cannot use PostMessage there.
x11 and wayland backends both create a custom GSource for this,
so there is no reason to not do that for win32.
https://bugzilla.gnome.org/show_bug.cgi?id=749601
Depending on the platform, it was only ever implemented to 1) set a
default surface size, 2) resize based on the video frame or 3) nothing.
Instead, provide a set_preferred_size () that elements/applications
can use to request a certain size which may be ignored for
videooverlay/other cases.
