This only needs to be initialized once but is in the hot path of creating
new paint nodes (for which we create many). Instead, do this as part of
the clutter_init() workflow to keep it out of the hot path.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1087
When calculating regions, a lot of temporary allocations are created. For
the array of rects (which is often a short number of them) we can use
stack allocations up to 1 page (256 cairo_rectangle_int_t). For building
a region of rectangles, cairo and pixman are much faster if you have all
of the rectangles up front or else it mallocs quite a bit of temporary
memory.
If we re-use the cairo_rectangle_int_t array we've already allocated (and
preferably on the stack), we can delay the creation of regions until after
the tight loop.
Additionally, it requires fewer allocations to union two cairo_region_t
than to incrementally union the rectangles into the region.
Before (percentages are of total number of allocations)
TOTAL FUNCTION
[ 100.00%] [Everything]
[ 100.00%] [gnome-shell --wayland --display-server]
[ 99.67%] _start
[ 99.67%] __libc_start_main
[ 99.67%] main
[ 98.60%] meta_run
[ 96.90%] g_main_loop_run
[ 96.90%] g_main_context_iterate.isra.0
[ 96.90%] g_main_context_dispatch
[ 90.27%] clutter_clock_dispatch
[ 86.54%] _clutter_stage_do_update
[ 85.00%] clutter_stage_cogl_redraw
[ 84.98%] clutter_stage_cogl_redraw_view
[ 81.09%] cairo_region_union_rectangle
After (overhead has much dropped)
TOTAL FUNCTION
[ 100.00%] [Everything]
[ 99.80%] [gnome-shell --wayland --display-server]
[ 99.48%] _start
[ 99.48%] __libc_start_main
[ 99.48%] main
[ 92.37%] meta_run
[ 81.49%] g_main_loop_run
[ 81.49%] g_main_context_iterate.isra.0
[ 81.43%] g_main_context_dispatch
[ 39.40%] clutter_clock_dispatch
[ 26.93%] _clutter_stage_do_update
[ 25.80%] clutter_stage_cogl_redraw
[ 25.60%] clutter_stage_cogl_redraw_view
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1071
g_signal_emit_by_name() is used to emit signals on ClutterContainer when
actors are removed or added. It happens to do various interface lookups
which are a bit unneccessary and can allocate memory.
Simply using emission wrappers makes all of that go away.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1083
Add API to ClutterSeat that allows inhibiting the unsetting of the
pointer focus surface. This can be useful for drawing custom cursor
textures like the magnifier of gnome-shell does.
In the future this API should also control unsetting of Clutters
focus-actor, not just the focus surface, that's not really needed right
now since we never unset the focus-actor anyway.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1077
Which offscreens actor rendering only in cases where it hasn't changed for
2 frames or more. This avoids the performance penalty of offscreening an
actor whose content is trying to animate at full frame rate. It will
switch automatically.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1069
If the transform matrix is an identity, then positioning wont change and
we can avoid creating the transform node altogether. This is based on
a similar find in GTK today while reducing temporary allocations.
This cuts the number of transforms created in clutter_actor_paint() by
about half under light testing of GNOME Shell from 6.8% to 2.4% of
allocations.
Before:
ALLOCATED TOTAL FUNCTION
[ 20.4 MiB] [ 21.20%] clutter_actor_paint
[ 11.0 MiB] [ 11.45%] clutter_paint_node_paint
[ 6.6 MiB] [ 6.84%] clutter_transform_node_new
[ 2.5 MiB] [ 2.61%] clutter_actor_node_new
After:
ALLOCATED TOTAL FUNCTION
[ 33.4 MiB] [ 24.12%] clutter_actor_paint
[ 26.2 MiB] [ 18.91%] clutter_paint_node_paint
[ 3.4 MiB] [ 2.43%] clutter_actor_node_new
[ 3.3 MiB] [ 2.41%] clutter_transform_node_new
Allocation amounts will have differed due to different amounts of running
time, but the % of allocations has now dropped below
clutter_actor_node_new() which should be expected.
https://gitlab.gnome.org/GNOME/mutter/issues/1056
And the corresponding getter. This property returns FALSE by default
and must be overridden by subclasses. This will allow gnome-shell to
hook up specific behavior that should not happen on mouse+keyboard
setups.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1044
If an actor sets flag `CLUTTER_ACTOR_NO_LAYOUT` then that means it
is (or should be) unaffected by `queue_relayout` calls in its children.
So we can avoid propagating `queue_relayout` all the way up to the stage
and avoid a full stage relayout each time.
But those children whose parent has `CLUTTER_ACTOR_NO_LAYOUT` still need
to be allocated at some point. So we do it at the same point where it
happened before. Only we now queue a *shallow* relayout so the `allocate`
run on the next frame doesn't need to descend the whole actor tree anymore.
Only a subtree and hopefully very small.
For free-floating and top-level actors this provides a measurable
performance benefit. According to Google Profiler, calls to
`_clutter_stage_maybe_relayout` are now so cheap that they no longer show
up in performance profiles.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/575
The private function `_clutter_input_device_update()` is not currently
exported.
This function calls `_clutter_input_device_set_actor()` which updates
the `ClutterActor` under the pointer, so making that function available
outside of Clutter will allow to make sure the pointer device actor is
updated prior to do picking.
Also, now that the functions is exported to the upper layers, drop the
underscore suffix from the function name.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1026
Right now the CONTENT_SIZE request mode for a ClutterActor is only
respected by `clutter_actor_get_preferred_size()`, but not by
`get_preferred_width()` and `get_preferred_height()`. Those simply try
to ask the layout manager and will return [0, 0] for actors without
children. So be consistent and also return the content size in those two
functions.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1019
As recommended by the docs for `g_settings_schema_source_get_default`:
> The returned source may actually consist of multiple schema sources
> from different directories, depending on which directories were given
> in XDG_DATA_DIRS and GSETTINGS_SCHEMA_DIR. For this reason, all lookups
> performed against the default source should probably be done recursively.
Now it's actually found and works again, including subpixel font smoothing.
Closes: https://gitlab.gnome.org/GNOME/gnome-shell/issues/1447https://gitlab.gnome.org/GNOME/mutter/merge_requests/1017
ClutterActors width and height can be reset to automatically use the
preferred (calculated) value by setting the width or height to -1, so
far this only works by setting it using `clutter_actor_set_width()` or
`clutter_actor_set_height()`, make sure it can also be done using the
"width" and "height" GObject properties.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/1018
Some ClutterOffscreenEffect subclasses, such as ClutterBrightnessContrastEffect,
early-return FALSE in pre-paint before chaining up. It's an important optimization
that avoids creating or updating the offscreen framebuffer.
However, if an offscreen framebuffer already exists by the time pre-paint fails,
it will be used *without* repaint the actor over it. That causes an old picture
of the actor to be displayed.
Fix that by always clearing the offscreen framebuffer when pre-paint fails.
Fixes https://gitlab.gnome.org/GNOME/mutter/issues/810https://gitlab.gnome.org/GNOME/mutter/merge_requests/992
When changing the 'enabled' property and disabling the offscreen effect,
it doesn't make sense to preserve the offscreen framebuffer. It's not
drawing, after all.
Furthermore, because ClutterOffscreenEffect only checks if the offscreen
framebuffer exists to decide whether or not to redraw, keeping the fbo
alive is a waste of resources.
Clear the offscreen framebuffer when the effect is disabled or enabled.
Fixes https://gitlab.gnome.org/GNOME/mutter/issues/810https://gitlab.gnome.org/GNOME/mutter/merge_requests/992
FLT_MIN is the smallest *positive* number above 0 that can be
represented as floating point number. If this is used to initialize the
maximum x/y coordinates of a rectangle, this will always be used if all
x/y coordinates of the rectangle are negative. This means that picking
at 0,0 will always be a hit for such rectangles.
Since mutter creates such a window for server side decorations on X11,
this window will always be picked at 0,0 preventing clicking/hovering
the activities button in gnome-shell at that coordinate.
Fixes https://gitlab.gnome.org/GNOME/mutter/issues/893
When rendering on-stage, it might be necessary to push offscreen
framebuffers to the paint context by external consumers, such as
GNOME Shell effects.
Expose clutter_paint_context_push|pop_framebuffer().
https://gitlab.gnome.org/GNOME/mutter/merge_requests/955
They have been deprecated for a long time, and all their uses in clutter
and mutter has been removed. This also removes some no longer needed
legacy state tracking, as they were only ever excercised in certain
circumstances when there was sources (pipelines or materials) on the now
removed source stack.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
Stop using API that uses the implicit Cogl framebuffer stack, (e.g.
cogl_push_matrix()) and replace usage by the corresponding API taking an
explicit framebuffer (e.g. cogl_framebuffer_push_matrix()).
For offscreens etc, the offscreen framebuffer is still pushed to and
popped from the Cogl framebuffer stack, so that paint nodes still draw
to the right framebuffer.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
While we still push and pop to the Cogl framebuffer stack, as so is
still needed to render the actors correctly, don't use the API using the
implicit framebuffer stack ourself in the offscreen effect code.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
clutter_paint_node_get_framebuffer() fell back on
cogl_get_draw_framebuffer() when the root node didn't have a custom
get_framebuffer vfunc. As this relies on deprecated implicit Cogl stack
API, it needs to go away, so handle this in the caller that knows more
about the context.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
Instead of using the intermediate stage state "active framebuffer" to
find the framebuffer a paint eventually targets, use the "base
framebuffer" of the paint context, as this more correctly corresponds to
the end point of a paint. It also means we can then later remove this
intermediate state from the stage.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
Instead of pushing and popping the Cogl framebuffer stack, use the
framebuffer passed around using the pick context. This removes usage of
the deprecated framebuffer stack when picking.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
Rendering off stage we never cull, and previously this was checked by
comparing the "active framebuffer" of the stage, to the current
framebuffer in the cogl stack. Replace this by checking whether the
current paint context is currently drawing on stage or not.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
Just as with painting, add a pick context that carries pick related
temporary state when doing actor picking. It is currently unused, and
will at least at first still carry around a framebuffer to deal track
view transforms etc.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
When painting, actors rely on semi global state tracked by the state to
get various things needed for painting, such as the current draw
framebuffer. Having state hidden in such ways can be very deceiving as
it's hard to follow changes spread out, and adding more and more state
that should be tracked during a paint gets annoying as they will not
change in isolation but one by one in their own places. To do this
better, introduce a paint context that is passed along in paint calls
that contains the necessary state needed during painting.
The paint context implements a framebuffer stack just as Cogl works,
which is currently needed for offscreen rendering used by clutter.
The same context is passed around for paint nodes, contents and effects
as well.
In this commit, the context is only introduced, but not used. It aims to
replace the Cogl framebuffer stack, and will allow actors to know what
view it is currently painted on.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/935
We do check the clip area as an optimization to know which input devices
might need updating state after a relayout (Assuming that if a device is
under a non-painted area, it's actor beneath didn't change).
Use the clip region for this, and drop the last usage of the clip region
bounds.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/867
This commit was split out from `cleanup: Use g_clear_signal_handler()
where possible` as it fixes an actual signal leak and should therefore
get backported to stable releases.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/940
This is inspired by 98892391d7 where the usage of
`g_signal_handler_disconnect()` without resetting the corresponding
handler id later resulted in a bug. Using `g_clear_signal_handler()`
makes sure we avoid similar bugs and is almost always the better
alternative. We use it for new code, let's clean up the old code to
also use it.
A further benefit is that it can get called even if the passed id is
0, allowing us to remove a lot of now unnessecary checks, and the fact
that `g_clear_signal_handler()` checks for the right type size, forcing us
to clean up all places where we used `guint` instead of `gulong`.
No functional changes intended here and all changes should be trivial,
thus bundled in one big commit.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/940
CallyTexture is an accessibility object associated with ClutterTexture.
ClutterTexture is going away, so prepare by first removing the
accessibility object that would be constructed for it.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/932
clutter_event_get_scroll_finish_flags() should return a ClutterScrollFinishFlags
but due to what looks like a bad copy/paste it instead returns a
ClutterScrollSource on asserts.
The definitions of the enums are these:
typedef enum
{
CLUTTER_SCROLL_SOURCE_UNKNOWN,
CLUTTER_SCROLL_SOURCE_WHEEL,
CLUTTER_SCROLL_SOURCE_FINGER,
CLUTTER_SCROLL_SOURCE_CONTINUOUS
} ClutterScrollSource;
typedef enum
{
CLUTTER_SCROLL_FINISHED_NONE = 0,
CLUTTER_SCROLL_FINISHED_HORIZONTAL = 1 << 0,
CLUTTER_SCROLL_FINISHED_VERTICAL = 1 << 1
} ClutterScrollFinishFlags;
The asserts would only return CLUTTER_SCROLL_SOURCE_UNKNOWN. This
is equal to CLUTTER_SCROLL_FINISHED_NONE which this patch uses
instead. Thus no functional change is intended. This only fixes a
compile warning.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/931
Clutter has a draw debug mode that allows for painting
paint volumes. Right now, this debug mode uses the old
immediate paint mode.
Switch the painting of paint volumes to use paint nodes,
and sneak a few minor style cleanups.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/890
Now that we unconditionally use ClutterActorNode to
paint ClutterActors, move the PAINT private flag to
the ClutterActorNode. This way, we can run the paint
on the actor anywhere inside the paint tree.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/890
When setting the root node as child of a clip or transform node, we add a
new reference to it, without removing the one that we've previously added
when getting it from the actor node (and that won't ever be unset by the
auto-pointer since the root_node is re-associated).
So, once we add the root node as child and re-define it, unref it.
Fixes https://gitlab.gnome.org/GNOME/mutter/issues/908
Previously, we would use a single offscreen framebuffer for both
transformations and when a shadow framebuffer should be used, but that
can be dreadfully slow when using software rendering with a discrete GPU
due to bandwidth limitations.
Keep the offscreen framebuffer for transformations only and add another
intermediate shadow framebuffer used as a copy of the onscreen
framebuffer.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/877
A compositor is notably opaque (usually has nothing to be painted on!).
gnome-shell sets this hint, but there's no reason why we wouldn't want
it by default.
Also, the color buffer being cleared messes with stencil clips, as the
clear operation by definition ignores the stencil buffer. We want to
use these more extensively in the future, so just drop this API.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/911
This reverts commit 4918893326.
This commit prevented cogl_stage_cogl_redraw_view() from skipping
swap buffers entirely if the invalidation region ended up empty.
This meant we were actually swapping buffers when we didn't need to.
The source of the glitches was fixed more properly, so this just adds
extra work.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/898
This way, we can simply pop up the Looking Glass and run:
>>> Meta.add_clutter_debug_flags(Clutter.DebugFlag.PICK, 0, 0)
And measure specific actions or events on GNOME Shell.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/862
As we do not prevent the SwapBuffers call from happening, those also
do count. Results in clip area calculations to be right for monitors
that previously did not get invalidated.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/888
Make ClutterActor paint using ClutterTransformNode, ClutterClip
node, and ClutterActorNode. Essencially, the actor node is a
replacement for clutter_actor_continue_paint().
An interesting aspect of this commit is that the order of the
operations is reversed to be preserved.
Before being able to remove the dummy node hack, we'll need to
make ClutterEffects compatible with paint nodes first -- and
naturally, that's enough content for its own merge request.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/872
ClutterActorNode is a paint node that runs the 'paint'
function of an actor. It is a useful helper node to be
used during the transition to paint nodes.
The role of ClutterActorNode will change over time. For
now, it is just a call to clutter_actor_continue_paint(),
which also paints the effects. When ClutterEffect is
ported to paint nodes, ClutterActorNode will morph to
only notify the actor about the painting, and will become
a private node to Clutter.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/872
Previously picking was done on an int (x,y) to address a particular pixel.
While `int` was the minimum precision required, it was also an unnecessary
type conversion.
The callers (input events mainly) all provide float coordinates and the
internal picking calculations also have always used floats. So it was
inconsistent and unnecessary to drop to integer precision in between those.
ABI break: This changes the parameter types for public function
`clutter_stage_get_actor_at_pos`, but its documentation is already
sufficiently vague to not need changing.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/844
This is an extremely straightforward and minimalistic port of
CoglVector APIs to the corresponding Graphene APIs.
Make ClutterPlane use graphene_vec3_t internally too, for the
simplest purpose of keeping the patch focused.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/458
Mutter requires Clutter, which requires Cogl. That means
Clutter requires all Cogl dependencies, and Mutter requires
all Clutter dependencies as well.
However, currently, Clutter does not pull in its dependencies,
which means we need to link against Cogl manually.
Add Clutter dependencies to declare_dependency() so that the
graphene dependency only needs to be declared once, for Cogl,
and pulled together.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/458
This is a deprecated property that is not used anywhere
in the codebase. Not by GNOME Shell. Because it uses the
deprecated ClutterGeometry type, it's a good target for
cleaning up, given that ClutterGeometry will be dropped
later on.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/458
Fog is explicitly deprecated in favour of CoglSnippet API,
and in nowhere we are using this deprecated feature, which
means we can simply drop it without any sort of replacement.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/458
When clutter actors with key focus are destroyed we emit ::key-focus-out on
them just after their destruction. This is against our assumption that no
signal should be emitted after "::destroy" (see GNOME/mutter!769 [1]), and
in fact could cause the shell to do actions that we won't ever stop on
destroy callback.
To avoid this to happen, use a private function to set its key-state (so we
can avoid looking for the stage) and emit ::key-focus-in/out events and use
this value in both clutter_actor_has_key_focus(),
clutter_actor_grab_key_focus() and on unmap and destruction to unset the
stage key focus before we emit the ::destroy signal.
As result of this, we can now avoid to unset the key focus on actor
destruction in the stage.
[1] https://gitlab.gnome.org/GNOME/mutter/merge_requests/769
Fixes https://gitlab.gnome.org/GNOME/gnome-shell/issues/1704
Clutter had support for internal children in its early revisions, but they
were deprecated for long time (commit f41061b8df, more than 7 years ago) and
no one is using them in both clutter and in gnome-shell.
So remove any alternative code path that uses internal children.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/816
This is for all intents and purposes the same as
`cogl_object_ref/unref`, but still refers to handles rather than
objects (while we're trying to get rid of the former) so it's a bit of
unnecessary redundant API.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/451
The default value of the ClutterShaderEffect:shader-type
property is CLUTTER_FRAGMENT_SHADER. However, because the
struct field is not actually initialized to it, it ends
up assuming the value 0, which is CLUTTER_VERTEX_SHADER.
Properly initialize ClutterShaderEffect's shader_type to
CLUTTER_FRAGMENT_SHADER.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/846
ClutterActor took a reference in its transition 'stopped' handler,
aiming to keep the transition alive during signal emission even if it
was removed during. This is, however, already taken care of by
ClutterTimeline, by always taking a reference during its 'stopped'
signal emission, so no need to add another one.
This also has the bonus of making reference ownership simpler, as well
as avoidance of double free if an actor was destroyed before a
transition has finished.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/828
Implicit transitions had a referenced taken while emitting the
completion signals, but said reference would only be released if it was
had remove-on-complete set to TRUE.
Change this to instead remove the 'is_implicit' state and mark all
implicit transitions as remove-on-complete. This fixes a
ClutterPropertyTransition leak in gnome-shell triggered by e.g. showing
/ hiding menus.
Fixes: https://gitlab.gnome.org/GNOME/gnome-shell/issues/1740https://gitlab.gnome.org/GNOME/mutter/merge_requests/828
The final version of the function was changed to allow points that are
touching the edge of a quadrilateral to be counted as "inside". Update
the function documentation to refect this.
Also clarify that the function is written in such a way that it is
agnostic to clockwise or anticlockwise vertex ordering.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/783
In `clutter_stage_view_blit_offscreen()`, the given clipping rectangle
is in “view” coordinates whereas we intend to copy the whole actual
framebuffer, meaning that we cannot use the clipping rectangle.
Use the actual framebuffer size, starting at (0, 0) instead.
That fixes the issue with partial repainting with shadow framebuffer
when fractional scaling is enabled.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/820
Clutter actors might emit property changes in dispose, while unparenting.
However we assume that the ::destroy signal is the last one we emit for an
actor, and that starting from this moment the object is not valid anymore,
and so we don't expect any signal emission from it.
To avoid this, freeze the object notifications on an actor during its
disposition, just before the ::destroy signal emission.
Update the actor-destroy test to verify this behavior.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/769
Clutter actors unset their parent on dispose, after emitting the ::destroy
signal, however this could cause ::parent-set signal emission. Since we
assume that after the destruction has been completed the actor isn't valid
anymore, and that during the destroy phase we do all the signal / source
disconnections, this might create unwanted behaviors, as in the signal
callbacks we always assume that the actor isn't in disposed yet.
To avoid this, don't emit ::parent-set signal if the actor is being
destroyed.
Update the actor-destroy test to verify this behavior.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/769
If there is no transformation, use `cogl_blit_framebuffer()` as a
shortcut in `clutter_stage_view_blit_offscreen()`, that dramatically
improves performance when using a shadow framebuffer.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/809
Delayed clutter timelines might be removed while they are still in the
process of being executed, but if they are not playing yet their delay
timeout won't be stopped, causing them to be executed anyway, leading to a
potential crash.
In fact if something else keeps a reference on the timelines (i.e. gjs), the
dispose vfunc delay cancellation won't take effect, causing the timelines to
be started and added to the master clock.
To avoid this, expose clutter_timeline_cancel_delay() function and call it
if a timeline is not playing but has a delay set.
Fixes https://gitlab.gnome.org/GNOME/mutter/issues/815https://gitlab.gnome.org/GNOME/mutter/merge_requests/805
If a timeline is delayed and we request to stop or pause it, we are emitting
the "::paused" signal on it, however this has never been started, and so
nothing has really be paused.
So, just try to cancel the delay on pause and return if not playing.
No code in mutter or gnome-shell is affected by this, so it is safe to
change.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/805
Clutter stage used to compute the initial projection using a fixed z
translation which wasn't matching the one we computed in
calculate_z_translation().
This caused to have a wrong initial projection on startup which was then
correctly recomputed only at the first paint.
However, since this calculation doesn't depend on view, but only on viewport
size, perspective's fovy and z_near we can safely do this at startup and
only when any of those parameters change.
Then we can move the computation out _clutter_stage_maybe_setup_viewport()
since the cogl framebuffer viewport sizes aren't affecting this.
Fixes https://gitlab.gnome.org/GNOME/gnome-shell/issues/1639https://gitlab.gnome.org/GNOME/mutter/merge_requests/803
