The macros we had for checking for toplevel windows were passing
through the root window, which was not intentional and meant that
for the root window WINDOW_IS_TOPLEVEL() returned TRUE but
window->impl->toplevel was NULL, causing gdk_window_create_cairo_surface()
to crash.
* remove gdk_frame_clock_get_frame_time_val(); a convenience
function that would rarely be used.
* remove gdk_frame_clock_get_requested() and
::frame-requested signal; while we might want to eventually
be able to track the requested phases for a clock, we don't
have a current use case.
* Make gdk_frame_clock_freeze/thaw() private: they are only
used within GTK+ and have complex semantics.
* Remove gdk_frame_clock_get_last_complete(). Another convenience
function that I don't have a current use case for.
* Rename:
gdk_frame_clock_get_start() => gdk_frame_clock_get_history_start()
gdk_frame_clocK_get_current_frame_timings() => gdk_frame_clock_get_timings()
Since we're not exporting the ability to create your own frame
clock for now, remove the setters for GdkFrameTimings fields.
Also remove all setters and getters for fields that are more
about implementation than about quantities that are meaningful
to the applcation and just access the fields directly within
GDK.
Now that GdkFrameClock is a class, not interface, there's no real advantage
to splitting the frame history into an aggregate object, so directly
merge it into GdkFrameClock.
Instead of making the frame clock a settable property of a window, make
toplevel windows inherently have a frame clock when created (getting
rid of the default frame clock.) We need to create or destroy frame
clocks when reparenting a window to be a toplevel, or to not be a
toplevel, but otherwise the frame clock for a window is immutable.
If we get a focus event for a X window we don't recognize, just
ignore it and avoid a g-critical when
_gdk_device_manager_core_handle_focus() is called with a NULL window.
Deprecate gdk_window_enable_synchronized_configure() and
gdk_window_configure_done() and make them no-ops. Implement the
handling of _NET_WM_SYNC_REQUEST in terms of the frame cycle -
we know that all processing will be finished in the next frame
cycle after the ConfigureNotify is received.
For an operation like synchronizing audio to video playback, we need to
be able to predict the time that a frame will be presented. The details
of this depend on the windowing system, so make the backend predict
a presentation time for ::begin-frame and set it on the GdkFrameTimings.
The timing algorithm of GdkFrameClockIdle is adjusted to give predictable
presentation times for frames that are not throttled by the windowing
system.
Helper functions:
gdk_frame_clock_get_current_frame_timings()
gdk_frame_clock_get_refresh_info()
are added for operations that would otherwise be needed multiple times
in different locations.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
We want the compositor to do different things for frames where
"slept before" is TRUE. Communicate to the compositor that
frame is a no-delay frame (slept_before=FALSE) by ending the frame
by increasing the counter value by 1, and that the frame is a
normal frame (slept_before=TRUE) by increasing the counter value
by 3.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
In order to be able to track statistics about how well we are drawing,
and in order to be able to do sophisticated things with frame timing
like predicting per-frame latencies and synchronizing audio with video,
we need to be able to track exactly when previous frames were drawn
to the screen.
Information about each frame is stored in a new GdkFrameTimings object.
A new GdkFrameHistory object is added which keeps a queue of recent
GdkFrameTimings (this is added to avoid further complicating the
implementation of GdkFrameClock.)
https://bugzilla.gnome.org/show_bug.cgi?id=685460
Instead of communicating the start of a frame to the window manager
as soon as we begin a frame, start a frame only when we know we've
actually created damage to the contents of a window.
(This uses cairo_set_mime_data() as a notification mechanism - a
clever suggestion from Uli Schlachter.)
The advantage of this is that we aren't forcing the compositor to
do a frame cycle and send _NET_WM_FRAME_DRAWN - depending on how the
compositor is structured that might either cause it to do extra
work or it might send _NET_WM_FRAME_DRAWN early and upset frame
timing.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
Unqueuing events from the windowing system when paused could result
in weird reordering if event filters resulted in application-visible
behavior. Since we now resume events when the frame clock is frozen,
we now no longer count on low-level event handling running while
event handling is paused.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
By starting with an odd frame counter value, we make the mapping
and initial paint of the window an atomic operation, avoiding
any visual artifacts from an unpainted window.
Possible improvement: start the frame when doing gdk_window_show(),
so that the same improvement occurs for windows that were previously
shown and are being mapped again.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
When a window is unmapped, freeze its frame clock. This avoids doing
unnecessary work, but also means that we won't block waiting for
_NET_WM_FRAME_DRAWN messages that will never be received since the
frame ended while the window was withdrawn.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
As part of the extended _NET_WM_SYNC_REQUEST_COUNTER protocol,
we get a _NET_WM_FRAME_DRAWN message for each frame we draw. Use this
to synchronize the updates we are doing with the compositing manager's
drawing, and ultimately with with display refresh.
We now set the sync request counters on all windows, including
override-redirect windows, since it is also useful to do synchronized,
atomic updates for such windows.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
By exporting two XSync counters on a toplevel window, we subscribe
to an extended form of the _NET_WM_SYNC_REQUEST_COUNTER protocol,
where the window manager can initiate an atomic frame, as previously,
but the application can also do so by incrementing the new counter to
an odd value, and then to an even value to finish the frame.
See:
https://mail.gnome.org/archives/wm-spec-list/2011-October/msg00006.html
The support for 64-bit integers that GLib requires is used to
simplify the logic.
https://bugzilla.gnome.org/show_bug.cgi?id=685460
