It seems that this code is trying to transform from "surface coordinates"
(the size of texture that's being displayed) to "actor coordinates"
(the actor's allocation), but I can't find any place where the two are
different. As such, let's just go back to using "surface coordinates"
everywhere and see what breaks.
Ever since the change to create the output window synchronously at startup,
there hasn't been any time where somebody could set a stage region the
output window was ready, so this was effectively dead code.
https://bugzilla.gnome.org/show_bug.cgi?id=720631
I know it's confusing with the triple negative, but unredirected is how
we track it elsewhere: we have an 'unredirected' flag, and 'should_unredirect'.
https://bugzilla.gnome.org/show_bug.cgi?id=720631
We currently ignore the unobscured region when we have mapped clones in
meta_window_actor_process_damage and meta_window_actor_damage_all but
use it unconditionally when computing the paint volume.
This is wrong. We should ignore it there as well or we will end up with
empty clones if the cloned window is completly obscured
(like the tray icons in gnome-shell).
https://bugzilla.gnome.org/show_bug.cgi?id=721596
We need to do this for XWayland windows, since we only get the event
telling us they're an XWayland window after the compositor knows about
the window.
I know it's confusing with the triple negative, but unredirected is how
we track it elsewhere: we have an 'unredirected' flag, and 'should_unredirect'.
https://bugzilla.gnome.org/show_bug.cgi?id=720631
Ever since the change to create the output window synchronously at startup,
there hasn't been any time where somebody could set a stage region the
output window was ready, so this was effectively dead code.
We no longer unmap the toplevel windows during normal operation. The
toplevel state is tied to the window's lifetime.
Call meta_compositor_add_window / meta_compositor_remove_window instead...
Traditionally, WMs unmap windows when minimizing them, and map them
when restoring them or wanting to show them for other reasons, like
upon creation.
However, as metacity morphed into mutter, we optionally chose to keep
windows mapped for the lifetime of the window under the user option
"live-window-previews", which makes the code keep windows mapped so it
can show window preview for minimized windows in other places, like
Alt-Tab and Expose.
I removed this preference two years ago mechanically, by removing all
the if statements, but never went through and cleaned up the code so
that windows are simply mapped for the lifetime of the window -- the
"architecture" of the old code that maps and unmaps on show/hide was
still there.
Remove this now.
The one case we still need to be careful of is shaded windows, in which
we do still unmap the client window. Theoretically, we might want to
show previews of shaded windows in the overview and Alt-Tab, so we remove
the complex unmap tracking for this later.
For x defined below, x == -INT32_MAX assuming that the arithmetic
expression actually uses the fpu.
float f = 1.0f;
int32_t x = INT32_MAX * f;
This would result in the calculated clip width/height to be -INT_MAX
if the damage width/height is INT_MAX. To solve this, use a double
variable instead.
Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
https://bugzilla.gnome.org/show_bug.cgi?id=705502
We need to set the number of components on the CoglTextureRectangle to
prevent wasting too much GPU memory. As we need to do this before we call
cogl_texture_set_region, just remove the meta_texture_rectangle_new wrapper,
and make callers call cogl_texture_rectangle_new_with_size directly.
The shadow is added in the paint step, not as a separate actor,
so the raise is a no-op. It also gets rid of an annoying misspelling
that's driving me crazy.
In the past, MetaWindowGroup was allocated the size of the screen and
painted the size of the screen because it contained the screen background,
but now we also have the "top window group" which contains only popup
windows, so the allocation doesn't properly reflect the paint bounds
of the window group. Compute the paint bounds accurately from the
children.
https://bugzilla.gnome.org/show_bug.cgi?id=719669
Since subsurfaces won't have toplevel MetaWindowActors, we need to
use MetaSurfaceActor instead. These are embedded in the MetaWindowActor,
just like MetaShapedTexture was (in fact, MetaSurfaceActor now contains
a MetaShapedTexture)
Make MetaWindowActor chain up to the generic default MetaCullable
implementation, and remove the helper methods for MetaSurfaceActor
and MetaShapedTexture.
Instead of hardcoded knowledge of certain classes in MetaWindowGroup,
create a generic interface that all actors can implement to get parts of
their regions culled out during redraw, without needing any special
knowledge of how to handle a specific actor.
The names now are a bit suspect. MetaBackgroundGroup is a simple
MetaCullable that knows how to cull children, and MetaWindowGroup is the
"toplevel" cullable that computes the initial two regions. A future
cleanup here could be to merge MetaWindowGroup / MetaBackgroundGroup so
that we only have a generic MetaSimpleCullable, and move the "toplevel"
cullability to be a MetaCullableToplevel.
https://bugzilla.gnome.org/show_bug.cgi?id=714706
For clarity, rename meta_window_get_outer_rect() to match terminology
we use elsewhere. The old function is left as a deprecated
compatibility wrapper.
When a Wayland compositor, simply rely on the clutter actor allocation
changed signal to sync geometry and emit window actor size changed
signals.
Attaching a wl_buffer to a MetaShapedTexture will signal allocation
changed on the corresponding MetaSurfaceActor, which the MetaWindowActor
is listening to.
Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
https://bugzilla.gnome.org/show_bug.cgi?id=705502
Instead of having MetaWindowActor only have one single MetaShapedTexture
as actor drawing its content, introduce a new abstract MetaSurfaceActor
that takes care of drawing.
This is one step in the direction to decouple MetaWaylandSurface with a
MetaWindow and MetaWindowActor (except for shell/xdg surfaces) in order
to finally support subsurfaces like features, or any feature where
window is not drawn using a single texture.
The first step, implemented in this patch, is to not have
MetaWindowActor work directly with a shaped texture. There are still
some cases where it simply gets the texture and goes on as before, but
this should be changed by either removing the need of going via
MetaWindowActor or by adding some generic interface to MetaSurfaceActor
that doesn't limit its functionality to one shaped texture.
There should be no visible difference nor after this patch, but
meta_window_actor_get_texture() and meta_surface_actor_get_texture()
should be deprecated when equivalent functionality has been introduced.
Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
https://bugzilla.gnome.org/show_bug.cgi?id=705502
The current time offset calculation is wrong. It is supposed to calculate
the offset between the current time and the
"time where it message should be sent" (last_time + interval).
Fix the math to actually do that.
https://bugzilla.gnome.org/show_bug.cgi?id=709340
We must set x11_size_changed even if we are frozen, as every window
size change makes the X server drop the pixmap, and we might lose
the information at the next thaw() if the window changes size
twice in one frame (so we would keep drawing with the old pixmap
until something else causes another resize)
To properly resize clients, we need to send them configure events
with the size we computed from the constraint system, and
then check if the new size they ask is compatible with
our expectation.
Note that this does not handle interactive resizing yet, it
merely makes the API calls work for wayland clients.
https://bugzilla.gnome.org/show_bug.cgi?id=707401
If we skip getting the clip rectangle because we don't have an
allocation or a texture, don't intersect with the visible region.
This avoids a pixman warning of an invalid rectangle.
Reviewed by drago01 in IRC.
Switching meta/util.h to gi18n.h was wrong, mutter is a library
and needs gi18n-lib.h, but that cannot be included from a public
header (since it depends on config.h or command line options),
so split util.h into a public and a private part.
https://bugzilla.gnome.org/show_bug.cgi?id=707897
The meta_create_texture_pipeline function used to create a dummy 1x1
texture so that it could make sure that the all of the state that
affects the shader generation would be set on the template pipeline so
that Cogl could share the pipeline's shader with any other pipelines
that are just rendering a texture. This is no longer necessary because
the only thing that affects the shader generation is the texture type,
not the actual texture data and Cogl now has a function to explicitly
set the texture type which we can use instead. Additionally even if
the template mechanism is not used at all Cogl will still end up
reusing the same shader because it now has a shader cache which is
indexed by the pipeline state so pipeline's don't strictly need to
share ancestry in order to take advantage of it. However we still
might as well use the function because if there is a common ancestry
it is faster to look up the shader because Cogl doesn't need to hash
the pipeline state.
https://bugzilla.gnome.org/show_bug.cgi?id=707458
(cherry picked from commit c5bf60eab4)
Calling XIGrabDevice has no effect under wayland, because the
xserver is getting events from us. Instead, we need to use our
own interfaces for grabs.
At the same time, we can simplify the public API, as plugins
should always listen for events using clutter.
https://bugzilla.gnome.org/show_bug.cgi?id=705917
We must send frame_drawn and frame_timing messages to even when
we don't actually queue a redraw on screen to comply with the
WM sync spec.
So throttle such apps to down to a ~100ms interval.
https://bugzilla.gnome.org/show_bug.cgi?id=703332
When we get a damage event we update the window by calling
meta_shaped_texture_update_area which queues a redraw on the actor.
We can avoid that for obscured regions by comparing the damage area to
our visible area.
This patch causes _NET_WM_FRAME_DRAWN messages to be not sent in some cases
where they should be sent; they will be added back in a later commit.
https://bugzilla.gnome.org/show_bug.cgi?id=703332
When drawing entirely opaque regions, we traditionally kept blending on
simply because it made the code more convenient and obvious to handle.
However, this can cause lots of performance issues on GPUs that aren't
too powerful, as they have to readback the buffer underneath.
Keep track of the opaque region set by windows (through _NET_WM_OPAQUE_REGION,
Wayland opaque_region hints, standard RGB32 frame masks or similar), and draw
those rectangles separately through a different path with blending turned off.
https://bugzilla.gnome.org/show_bug.cgi?id=707019
Split out pipeline creation to a separate function so that we don't
have so much dense code in the paint function itself, and remove some
indentation levels.
Also, don't use our own template for the unmasked pipeline, since it
has nothing different from the default pipeline template.
We also don't store the pipelines anymore since their creation isn't
really helping us; we set the mask texture and paint texture on every
paint anyway.
https://bugzilla.gnome.org/show_bug.cgi?id=707019
We can't use the X11 stage window, if clutter is not using the X11
backend (and even if it was, it would be bogus when the xwayland
server is not the one clutter is talking to). Instead, we introduce
the concept of "focus type", which we use to differentiate the
various meanings of None in the focus_xwindow field.
https://bugzilla.gnome.org/show_bug.cgi?id=706364
Remove grab window and cursor from the API, and just grab always
on the stage window with no cursor.
This is mainly to remove the X11 usage in the public API, in preparation
for implementing this in wayland.
https://bugzilla.gnome.org/show_bug.cgi?id=705917
We want to show a dialog when a display change happens from the
control center. To do so, add a new vfunc to MetaPlugin and
call it when a configuration change is requested via DBus.
https://bugzilla.gnome.org/show_bug.cgi?id=705670
Instead of a full white background, make one with a random color.
This way the different "monitors" are visible and it's easier
to debug the DBus API.
https://bugzilla.gnome.org/show_bug.cgi?id=705670
We need to use g_signal_connect_object(), rather than g_signal_connect(),
because the window actor can be destroyed before the window emits
the final notify::appears-focused inside unmanage, if the plugin
decides that it doesn't want to animate the destruction (which
happens with dialogs and the default plugin)
https://bugzilla.gnome.org/show_bug.cgi?id=706207
We need to use g_signal_connect_object(), rather than g_signal_connect(),
because the window actor can be destroyed before the window emits
the final notify::appears-focused inside unmanage, if the plugin
decides that it doesn't want to animate the destruction (which
happens with dialogs and the default plugin)
https://bugzilla.gnome.org/show_bug.cgi?id=706207
The previous code was leaving focus fields dirty in MetaWaylandPointer
and MetaWaylandKeyboard at time (which could crash the X server
because of invalid object IDs)
The new code is more tighly integrated in the normal X11 code
for handling keyboard focus (meaning that the core idea of input
focus is also correct now), so that meta_window_unmanage() can
do the right thing. As a side benefit, clicking on wayland clients
now unfocus X11 clients.
For the mouse focus, we need to clear the surface pointer when
the metawindowactor is destroyed (even if the actual actor is
kept alive for effects), so that a repick finds a different pointer
focus.
https://bugzilla.gnome.org/show_bug.cgi?id=705859
Remove window_surfaces, as the FIXME asks for. We don't need it
because we can obtain the surface from the MetaWindow, and
follow the wayland compositor path for both types of clients.
https://bugzilla.gnome.org/show_bug.cgi?id=705818
This copies the basic input support from the Clayland demo compositor.
It adds a basic wl_seat implementation which can convert Clutter mouse
events to Wayland events. For this to work all of the wayland surface
actors need to be made reactive.
The wayland keyboard input focus surface is updated whenever Mutter
sees a FocusIn event so that it will stay in synch with whatever
surface Mutter wants as the focus. Wayland surfaces don't get this
event so for now it will just give them focus whenever they are
clicked as a hack to test the code.
Authored-by: Neil Roberts <neil@linux.intel.com>
Authored-by: Giovanni Campagna <gcampagna@src.gnome.org>
This adds support for running mutter as a hybrid X and Wayland
compositor. It runs a headless XWayland server for X applications
that presents wayland surfaces back to mutter which mutter can then
composite.
This aims to not break Mutter's existing support for the traditional X
compositing model which means a single build of Mutter can be
distributed supporting the traditional model and the new Wayland based
compositing model.
TODO: although building with --disable-wayland has at least been tested,
I still haven't actually verified that running as a traditional
compositor isn't broken currently.
Note: At this point no input is supported
Note: multiple authors have contributed to this patch:
Authored-by: Robert Bragg <robert@linux.intel.com>
Authored-by: Neil Roberts <neil@linux.intel.com>
Authored-by: Rico Tzschichholz.
Authored-by: Giovanni Campagna <gcampagna@src.gnome.org>
We now track whether a window has an input shape specified via the X
Shape extension. Intersecting that with the bounding shape (as required
by the X Shape extension) we use the resulting rectangles to paint
window silhouettes when picking. As well as improving the correctness of
picking this should also be much more efficient because typically when
only picking solid rectangles then the need to actually render and issue
a read_pixels request can be optimized away and instead the picking is
done on the cpu.
GNOME Shell's actors aren't touch capable, so we need to make sure that
they get the fallback pointer emulated events for now. This fixes the top
bar and other elements not working on a touchscreen without a grab.
https://bugzilla.gnome.org/show_bug.cgi?id=697192
Some cards have 2k texture limits, which can be smaller than
commonly sized backgrounds.
One way to get around this problem is to use Cogl's "sliced texture"
feature, that transparently uses several hardware textures under the hood.
This commit changes background textures loaded from file to potentially
use slicing. Based on a patch by Jasper St. Pierre
<jstpierre@mecheye.net>.
https://bugzilla.gnome.org/show_bug.cgi?id=702283
Some cards have 2k texture limits, which can be smaller than
commonly sized backgrounds.
This commit downscales the background in this situation, so that
it won't fail to load.
https://bugzilla.gnome.org/show_bug.cgi?id=702283
gnome-shell needs to know whether the stage window is focused so
it can synchronize between stage window focus and Clutter key actor
focus. Track all X windows, even those without MetaWindows, when
tracking the focus window, and add a compositor-level API to determine
when the stage is focused.
https://bugzilla.gnome.org/show_bug.cgi?id=700735
We substract one from the unredirect counter when enable_unredirect_for_screen
gets called. It is an unsigned integer so substracting one from zero (which means enable) would overflow and thus keep it peramently enabled.
This should never happen because it means there is an unmatched
enable / disable pair somewhere. So in addition to fixing it add a
warning when this case gets triggered.
https://bugzilla.gnome.org/show_bug.cgi?id=701224
Commit 4f2bb583bf changed things so that the compositor used
clutter_threads_add_repaint_func_full (CLUTTER_REPAINT_FLAGS_POST_PAINT
to get after-paint notification and send _NET_WM_FRAME_DRAWN, but this
doesn't actually work, since Clutter will already have blocked for
VBlank before calling post-paint functions.
The result is that frame synced toolkits like GTK 3.8 will normally
only be able to draw every other frame.
Since ::paint doesn't work either, a new function
clutter_stage_set_paint_callback() has been added to Clutter
(and will be included in the 1.14 branch)
https://bugzilla.gnome.org/show_bug.cgi?id=698794
gnome-shell has traditionally just called XSetInputFocus when wanting to
set the input focus to the stage window, but this might cause strange,
hard-to-reproduce bugs because of an interference with mutter's focus
prediction. Add API to allow gnome-shell to focus the stage window that
also updates mutter's internal focus prediction state.
https://bugzilla.gnome.org/show_bug.cgi?id=700735
The hierarchy handling is handled in the shell by adding stuff
directly to the uiGroup, and we have a dedicated actor for
the overview there, so we don't need this anymore.
https://bugzilla.gnome.org/show_bug.cgi?id=700735
This essentially just moves install_corners() from the compositor, through
the core, into the UI layer where it arguably should have been anyway,
leaving behind stub functions which call through the various layers. This
removes the compositor's special knowledge of how rounded corners work,
replacing it with "ask the UI for an alpha mask".
The computation of border widths and heights changes a bit, because the
width and height used in install_corners() are the
meta_window_get_outer_rect() (which includes the visible borders but not
the invisible ones), whereas the more readily-available rectangle is the
MetaFrame.rect (which includes both). Computing the same width and height
as meta_window_get_outer_rect() involves compensating for the invisible
borders, but the UI layer is the authority on those anyway, so it seems
clearer to have it do the calculations from scratch.
Bug: https://bugzilla.gnome.org/show_bug.cgi?id=697758
Signed-off-by: Simon McVittie <simon.mcvittie@collabora.co.uk>
Reviewed-by: Jasper St. Pierre <jstpierre@mecheye.net>
compositor/meta-background.c:64: error: redefinition of typedef 'MetaBackgroundPrivate'
./meta/meta-background.h:51: error: previous declaration of 'MetaBackgroundPrivate' was here
Right now we call unset_texture from MetaBackground's dispose method.
unset_texture assumes there's a pipeline available, but there may not
be if the object was just created.
This commit fixes that incorrect assumption.
https://bugzilla.gnome.org/show_bug.cgi?id=696157
Cogl automatically caches pipelines with no eviction policy,
so we need to make sure to reuse snippets to prevent
identical pipelines from getting cached separately.
https://bugzilla.gnome.org/show_bug.cgi?id=696157
g_task_propagate_pointer relinishes the GTask
of its reference to the propagated pointer, so we need to
unref it ourselves when we're done with it.
https://bugzilla.gnome.org/show_bug.cgi?id=696157
ClutterBinLayout's get_preferred_width / get_preferred_height
doesn't respect fixed child positioning when calculating the
size of the layout, but does when allocating. This is absurdly
broken, but it's what we're given. Use a ClutterFixedLayout,
which doesn't have these issues.
https://bugzilla.gnome.org/show_bug.cgi?id=696089
If _NET_WM_OPAQUE_REGION is set when the window is first mapped, the
initial load_properties will happen before the window actor is created,
and we'll have a call to meta_compositor_window_shape_changed. Just
fizzle this call out instead of doing anything fancy, as we'll pick
up the opaque region when the window actor is eventually created.
https://bugzilla.gnome.org/show_bug.cgi?id=695813
Window actors might be temporarily parented to intermediate actors during
effect, but we should not require that the plugin keeps track of stacking.
Rather, assume that the intermediate groups holds a whole stack, and
applying position within it.
https://bugzilla.gnome.org/show_bug.cgi?id=695711
When windows get redirected off screen, all that gets left behind
is black. We don't want to flicker black at startup, though.
This commit maps the overlay window early, before redirecting
toplevels, so they end up getting snapshotted onto the background
pixmap of the overlay window when the overlay window is mapped.
https://bugzilla.gnome.org/show_bug.cgi?id=694321
Send a _NET_WM_FRAME_DRAWN for each newly created window, as required
by the specification. This avoids a race where a window might be created
frozen but already unfrozen by the time we first see fetch the
counter value.
Remove a duplicate call to meta_compositor_set_updates_frozen() which
was called before the MetaWindowActor is created and hence did nothing.
https://bugzilla.gnome.org/show_bug.cgi?id=694771
The background vignette currently fits itself to the painted
texture, instead of the monitor. This causes some very
wrong looking drawing for backgrounds that don't fill the screen.
This commit reworks the vignette shader code to be clearer, more
correct, and parameterized so that it knows how to scale and
position the vignette.
https://bugzilla.gnome.org/show_bug.cgi?id=694393
The WALLPAPER style of background painting currently
draws starting in the upper left corner of each monitor.
This isn't really correct, it means the seam between
monitors doesn't match up and edges look unbalanced if
the tile isn't a multipe of monitor size.
Really, the tiles should be centered in the middle of
the screen. (Just like when tiling a bathroom floor,
tiles should start in the center of the room.)
This commit reworks the math to make that happen.
https://bugzilla.gnome.org/show_bug.cgi?id=694393
Commit 4f2bb583bf started to use a clutter_threads_add_repaint_func_full
callback instead of connecting to the stage's paint signal.
The callback has to return TRUE if it wants to be called again, so fix that
as we want to call it for every frame (otherwise apps supporting the WM SYNC
protocol will stop drawing).
https://bugzilla.gnome.org/show_bug.cgi?id=695006
Doing so causes useless full stage redraws and breaks culling
as clutter cannot know how the signal handler affects painting.
So use clutter_threads_add_repaint_func_full with the
CLUTTER_REPAINT_FLAGS_POST_PAINT flag instead.
https://bugzilla.gnome.org/show_bug.cgi?id=694988
There is currently code to try to fill gradients in a
hardware native format, using #ifdefs. That optimization is
unimportant since gradients only use 2 byte buffers. It's
also incorrect because it's getting the channel order wrong
at buffer initialization time.
This commit drops the ifdefs for clarity and fixes the
channel order.
https://bugzilla.gnome.org/show_bug.cgi?id=694641
Background handling in GNOME is very roundabout at the moment.
gnome-settings-daemon uses gnome-desktop to read the background from
disk into a screen-sized pixmap. It then sets the XID of that pixmap
on the _XROOTPMAP_ID root window property.
mutter puts that pixmap into a texture/actor which gnome-shell then
uses.
Having the gnome-settings-daemon detour from disk to screen means we
can't easily let the compositor handle transition effects when
switching backgrounds. Also, having the background actor be
per-screen instead of per-monitor means we may have oversized
textures in certain multihead setups.
This commit changes mutter to read backgrounds from disk itself, and
it changes backgrounds to be per-monitor.
This way background handling/compositing is left to the compositor.
https://bugzilla.gnome.org/show_bug.cgi?id=682427
actor_is_untransformed is a function meta-window-group uses to determine
if an actor is relatively pixel aligned and not contorted. It then
returns the coordinates of the actor.
In a subsequent commit will need the function in a different file, so
this commit separates it out.
https://bugzilla.gnome.org/show_bug.cgi?id=682427
Now that the background actor is reactive, this means that
clicks on the window group part of the stage, even when they're
on an X window, will be registered as the background actor, as
all of the other children of the group aren't reactive. This can
happen when a plugin takes a modal grab, for instance.
https://bugzilla.gnome.org/show_bug.cgi?id=681540
We do, in fact, need freezing to affect window geometry, so that
move-resize operations (such as an interactive resize from the
left, or a resize of a popup centered by the application) occur
atomically.
So to make map effects work properly, only exclude the initial
placement of a window from freezing. (In the future, we may want
to consider whether pure moves of a window being done in response
to a user drag should also be excluded from freezing.)
Rename meta_window_sync_actor_position() to
meta_window_sync_actor_geometry() for clarity.
https://bugzilla.gnome.org/show_bug.cgi?id=693922
If a window is frozen because it is repainting, that shouldn't kee[p
us from updating its position: we don't want a slow-to-update window
to move around the screen chunkily when dragged. (This does reduce
the efficiency of begin/end frames for replacing double-buffering,
but that never works very well in the case where there was an overlapping
window or the entire screen needed redrawing for whatever reason.)
This fixes a bug where a window that was mapped frozen would not get
positioned properly until after the map effect finished, and would
jump from 0,0 at that point. Since effects *do* need to prevent
actor repositioning by Mutter, we must position the actor before any
effect starts.
Because we now are queuing invalidates on frozen windows, fix the
logic for that so that we properly update everything when the window
unfreezes.
https://bugzilla.gnome.org/show_bug.cgi?id=693922
The WM spec requires _NET_WM_FRAME_DRAWN to *always* be sent when
there is an appropriate update to the sync counter value. We were
potentially missing _NET_WM_FRAME_DRAWN when an application did a
spontaneous update during an interactive resize and during effects.
Refactor the code to always send _NET_WM_FRAME_DRAWN, even when
a window is frozen.
https://bugzilla.gnome.org/show_bug.cgi?id=693833
Put override redirect windows such as menus into a separate window group
stacked above everything else. This will allow us to visually put these
above other compositior chrome.
Based on a patch from Muffin.
https://bugzilla.gnome.org/show_bug.cgi?id=633620
When a client is drawing as hard as possible (without sleeping
between frames) we need to draw as soon possible, since sleeping
will decrease the effective frame rate shown to the user, and
can also result in the system never kicking out of power-saving
mode because it doesn't look fully utilized.
Use the amount the client increments the counter value by when
ending the frame to distinguish these cases:
- Increment by 1: a no-delay frame
- Increment by more than 1: a non-urgent frame, handle normally
https://bugzilla.gnome.org/show_bug.cgi?id=685463
