With the introduction of the shallow relayout mechanism another small
but severe regression sneaked into our layout machinery: We might
allocate an actor twice during the same allocation cycle, with one
allocation happening using the wrong parent.
This issue happens when reparenting an actor from a NO_LAYOUT parent to
a non-NO_LAYOUT parent, in particular it triggered a bug in gnome-shell
when DND reparents a child from the NO_LAYOUT uiGroup to the overviews
Workspace actor after a drag ended. The reason the issue happens is the
following chain of events:
1. child of a NO_LAYOUT parent queues a relayout, this child is added to
the priv->pending_relayouts list maintained by ClutterStage
2. child is reparented to a different parent which doesn't have the
NO_LAYOUT flag set, another relayout is queued, this time a different
actor is added to the priv->pending_relayouts list
3. the relayout happens and we go through the pending_relayouts list
backwards, that means the correct relayout queued during 2. happens
first, then the old one happens and we simply call
clutter_actor_allocate_preferred_size() on the actor, that allocation
overrides the other, correct one.
So fix that issue by adding a method to ClutterStage which removes
actors from the pending_relayouts list again and call this method as
soon as an actor with a NO_LAYOUT parent is detached from the stage.
With that in place, we can also remove the check whether an actor is
still on stage while looping through pending_relayouts. In case
something else is going wrong and the actor is not on stage,
clutter_actor_allocate() will warn anyway.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1356
An actor may be placed without being on any current stage view; in this
case, to get the ball rolling, walk up the actor tree to find the first
actor where a frame clock can be picked from.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1285
The frame clock wouldn't be useable yet, but none the less, add API to
get the frame clock best suited for driving the actor. Currently this
translates to the fastest one, but that might change.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1285
Without an associated actor, or explicit frame clock set, in the future
a timeline will not know how to progress, as there will be no singe
frame clock to assume is the main one. Thus, deprecate the construction
of timelines without either an actor or frame clock set.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1285
This is so something outside of clutter-stage.c (i.e.
clutter-stage-view.c) can eventually do various things
_clutter_stage_do_update() does now while not redrawing the whole stage.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1285
When a transition is created for the allocation change, it will delay
the new allocation box getting set depending on transition details.
This, however, means that e.g. the 'needs_allocation' flag never gets
cleared if a transition is created, causing other parts of the code to
get confused thinking it didn't pass through a layout step before paint.
Fix this by calling clutter_actor_allocate_internal() with the current
allocation box if a transition was created, so that we'll properly clear
'needs_allocation' flag.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1345
Since we now have the neccessary infrastructure to get notified about
changes to the absolute transformation matrix, we can also invalidate
the stage-views list on updates to this matrix.
So rename absolute_allocation_changed() to absolute_geometry_changed()
to make it clear this function is not only about allocations, and call
that function recursively for all children on changes to the
transformation matrix, too.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1343
If we want to invalidate the stage-views list reliably on changes to the
actors transformation matrices, we also need to get notified about
changes to the custom transformations applied using the
apply_transform() vfunc.
So provide a new API that allows invalidating the transformation matrix
for actors implementing custom transformations, too. This in turn allows
us to cache the matrix applied using the apply_transform() vfunc by
moving responsibility of keeping track of the caching from
clutter_actor_real_apply_transform() to
_clutter_actor_apply_modelview_transform().
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1343
For ClutterText, the resource scale the text is drawn with affects the
size of the allocation: ClutterText will choose a font scale based on
the resource scale, and that font scale can lead to a slight difference
in size compared to the unscaled font.
We currently handle that by queuing a relayout inside the
"resource-scale-changed" signal handler. This solution is a bit
problematic though since it will take one more allocation cycle until
the allocation is actually updated after a scale-change, so the actor is
painted using the wrong allocation for one frame.
Also the current solution can lead to relayout loops in a few cases, for
example if a ClutterText is located near the edge on a 1x scaled monitor
and is moved to intersect a 2x scaled monitor: Now the resource scale
will change to 2 and a new allocation box is calculated; if this
allocation box is slightly smaller than the old one because of the new
font scale, the allocation won't intersect the 2x scaled monitor again
and the resource scale switches back to 1. Now the allocation gets
larger again and intersects the 2x scaled monitor again.
This commit introduces a way to properly support those actors: In case
an actors resource scale might affect its allocation, it should call the
private function clutter_actor_queue_immediate_relayout(). This will
make sure the actor gets a relayout before the upcoming paint happens
afte every resource scale change. Also potential relayout loops can
be handled by the actors themselves using a "phase" argument that's
passed to implementations of the calculate_resource_scale() vfunc.
The new API is private because resource scales are not meant to be used
in a way where the scale affects the allocation. With ClutterText and
the current behavior of Pango, that can't be avoid though, so we need it
anyway.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1276
Since we now always return a resource scale, we can remove the boolean
return value from clutter_actor_get_resource_scale() and
_clutter_actor_get_real_resource_scale(), and instead simply return the
scale.
While at it, also remove the underscore from the
_clutter_actor_get_real_resource_scale() private API.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1276
Now that ClutterActor has a convenient API for getting the stage views
an actor is presented on, we can remove a large part of the code for
resource-scale calculation and instead rely on the stage-views list.
The way this works is a bit different from the old resource scales:
clutter_actor_get_resource_scale() always returns a scale, but this
value is only guaranteed to be correct when called from a vfunc_paint()
implementation, in all other cases the value is guessed using the scale
of the parent actor or the last valid scale. Now in case the value
previously reported by clutter_actor_get_resource_scale() turns out to
be wrong, "resource-scale-changed" will be emitted before the next paint
and the actor has a chance to update its resources.
The general idea behind this new implementation is for actors which only
need the scale during painting to continue using
clutter_actor_get_resource_scale() as they do right now, and for actors
which need the resource scale on other occasions, like during size
negotiation, to use the scale reported by
clutter_actor_get_resource_scale() but also listen to the
"resource-scale-changed" signal to eventually redo the work using the
correct scale.
The "guessing" of the scale is done with the intention of always giving
actors a scale to work with so they don't have to fall back to a scale
value the actor itself has to define, and also with the intention of
emitting the "resource-scale-changed" signal as rarely as possible, so
that when an actor is newly created, it won't have to load its resources
multiple times.
The big advantage this has over the old resource scales is that it's now
safe to call clutter_actor_get_resource_scale() from everywhere (before,
calling it from size negotiation functions would usually fail). It will
also make it a lot easier to use the resource scale for complex cases
like ClutterText without risking to get into relayout loops.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1276
We're going to refactor resource scales, making the notification of
changes to the resource scale a lot more important than it is right now
(we won't guarantee queried scales are correct outside the paint cycle
anymore).
Having a separate signal/vfunc for this will make the difference between
the new clutter_actor_get_resource_scale() API (which can return a
guessed value) and the notification of changes to the resource scale
(which will be guaranteed to return an up-to-date value) more obvious.
So replace the "resource-scale" property of ClutterActor with a
"resource-scale-changed" signal that's emitted when the resource scale
is recalculated.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1276
It is deprecated in favor of the 'z-position' property, and
the implementation itself redirects to the z-position, so
just drop it and replace all get|set_depth calls to their
z-position counterparts.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1332
There are cases where a layout manager used by an actor also wants to
return a custom size when the actor has no children, for example in case
the layout manager requests a fixed size. This is currently impossible
because we only query the layout manager when calculating the preferred
size if the actor has children.
So fix that and also use the layout managers size negotiation functions
in case the actor has no children.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1322
Now that we have a proper way to mark our allocation as uninitialized,
make use of that and only disallow implicit transitions of the
"allocation" property if that is the case.
This fixes a bug where easing the allocation of an actor is impossible
when someone queued a relayout on it (or a child of it) before.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1290
We currently initialize the ClutterActorBox of the actors allocation to
zero, but there's a difference between a valid zero-allocation and an
actor having never been allocated. Currently it's impossible for us to
detect the latter case in a reliable way and we use the needs_allocation
flag for this, which may also be set in other situations.
So initialize the allocation of actors to the newly added UNINITIALIZED
ClutterActorBox, which will make it easier to detect whether an actor
already got its initial allocation.
This also fixes another issue right now: Actors which get allocated a
(valid) zero allocation, will now notify the "allocation" property in
this case.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1290
We currently go through the whole tree of mapped actors on every paint
cycle to update the stage views actors are on. Even if no actors need
updating of their stage views, traversing the actor tree is still quite
expensive and shows up when using a profiler.
So tone down the amounts of full-tree traversals we have to do on every
paint cycle and only traverse a subtree if it includes an actor which
actually needs updating of its stage views.
We do that by setting the `needs_update_stage_views` flag to TRUE
recursively for all parents up to the stage when the stage-views list of
an actor gets invalidated. This way we end up updating a few more actors
than necessary, but can avoid searching the whole actor tree for actors
which have `needs_update_stage_views` set to TRUE.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1196
Add a new signal that's emitted when the stage views an actor being
painted on have changed, "stage-views-changed". For example this signal
can be helpful when tracking whether an actor is painted on multiple
stage views or only one.
Since we must clear the stage-views list when an actor leaves the stage
(actors that aren't attached to a stage don't get notified about the
stage views being changed/replaced), we also emit the new signal when an
actor gets detached from the stage (otherwise there would be an edge
case where no signal is emitted but it really should: An actor is
visible on a stage view, then detached from the stage, and then attached
again and immeditely moved outside the view).
Also skip the comparison of the old stage-views list and the new one if
nobody is listening to the signal to save some resources.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1196
There are certain rendering techniques and optimizations, for example
the unredirection of non-fullscreen windows, where information about the
output/stage-view an actor is on is needed to determine whether the
optimization can be enabled.
So add a new method to ClutterActor that allows listing the stage-views
the actor is being painted on: clutter_actor_peek_stage_views()
With the way Clutter works, the only point where we can reliably get
this information is during or right before the paint phase, when the
layout phase of the stage has been completed and no more changes to the
actors transformation matrices happen. So to get the stage views the
actor is on, introduce a new step that's done on every master clock tick
between layout and paint cycle: Traversing through the actor tree and
updating the stage-views the mapped actors are going to be painted on.
We're doing this in a separate step instead of inside
clutter_actor_paint() itself for a few reasons: It keeps the code
separate from the painting code, making profiling easier and issues
easier to track down (hopefully), it allows for a new
"stage-views-changed" signal that doesn't interfere with painting, and
finally, it will make it very easy to update the resource scales in the
same step in the future.
Currently, this list is only invalidated on allocation changes of
actors, but not on changes to the transformation matrices. That's
because there's no proper API to invalidate the transformation matrices
ClutterActor implementations can apply through the apply_transform()
vfunc.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1196
When the stage views the stage is shown on are changed, ClutterStage
currently provides a clutter_stage_update_resource_scales() method
that allows invalidating the resource scales of all actors. With the new
stage-views API that's going to be added to ClutterActor, we also need a
method to invalidate the stage-views lists of actors in case the stage
views are rebuilt and fortunately we can re-use the infrastructure for
invalidating resource scales for that.
So since resource scales depend on the stage views an actor is on,
rename clutter_stage_update_resource_scales() and related methods to
clutter_stage_clear_stage_views(), which also covers resource scales.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1196
While the layout manager of a ClutterActor does get properly unset when
destroying an actor, we currently forget to disconnect the
"layout-changed" signal from it.
So do that, and while at it, also switch to using the signal id for
disconnecting from the signal instead of
g_signal_handlers_disconnect_by_func(), which caused problems before
because it might traverse the signal handler list.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1281
We currently are confusing g_param_spec_enum and g_param_spec_flags for
the offscreen-redirect property of ClutterActor. Since it's actually a
flag, make it a flag everywhere.
Fun fact: This was already partly done with
d7814cf63eab1cf95625b06face9f914133d7eaa, but that commit missed the
setter.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1292
For actors which don't have needs_allocation set to TRUE and where the
new allocation wouldn't be different from the old one, the allocate()
vfunc doesn't have to be called. We still did this in case a parent
actor was moved though (so the absolute origin changed), because we
needed to propagate the ABSOLUTE_ORIGIN_CHANGED allocation flag down to
all actors.
Since that flag is now removed and got replaced with a private property,
we can simply notify the children about the absolute allocation change
using the existing infrastructure and safely stop allocating children at
this point.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1247
With commit 0eab73dc2e we introduced an optimization of not doing
allocations for actors which are hidden. This broke the propagation of
absolute origin changes to hidden actors, so if an actor is moved while
its child is hidden, the child will not get
priv->needs_compute_resource_scale set to TRUE, which means the resource
scale won't be updated when the child gets mapped and shown again.
Since we now have priv->absolute_origin_changed, we can simply check
whether that is TRUE for our parent before bailing out of
clutter_actor_allocate() and if it is, notify the whole hidden sub-tree
about the absolute origin change.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1247
When manipulating the allocation of a ClutterActor from an allocate()
vfunc override, clutter_actor_set_allocation() is used to let Clutter
know about the changes.
If the actors allocation or its absolute origin did not change before
that, this can also affect the actors absolute_origin_changed property
used by the children to detect changes to their absolute position.
So fix this bug (which luckily didn't seem to affect us so far) and set
priv->absolute_origin_changed to TRUE in case the origin changes inside
clutter_actor_set_allocation_internal(). Since this function is always
called when our allocation changes, we no longer need to update
absolute_origin_changed in clutter_actor_allocate() now.
Since a change to the absolute origin always affects the resource scale,
too, we also need to move that check from clutter_actor_allocate() here
to make sure we update the resource scale.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1247
Since the introduction of the shallow relayout functionality it's
possible to start an allocation cycle at any point in the tree, not only
at the stage. Now when starting an allocation at an actor that's not the
stage, we'd still look at the absolute_origin_changed property of this
actors parent, which might still be set to TRUE from the parents last
allocation.
So avoid using the parents absolute_origin_changed property from the
last allocation in case a shallow relayout is being done and always
reset the absolute_origin_changed property to FALSE after the allocation
cycle.
This broke with the removal of the ABSOLUTE_ORIGIN_CHANGED
ClutterAllocationFlag that was done in commit dc8e5c7f.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1247
All existing users of clutter_actor_has_mapped_clones() actually want to
know whether the actor is being cloned by a visible clone, it doesn't
matter to them if that clone is attached to an actor somewhere else in
the tree or to the actor itself.
So make clutter_actor_has_mapped_clones() a bit more convenient to use
and also check the clones of the parent-actors in that function.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1235
The comment in _clutter_actor_get_allocation_clip() explicitely notices
that it doesn't need the behavior of doing an immediate relayout as
clutter_actor_get_allocation_box() does. The comment is also still valid
since the code calling _clutter_actor_get_allocation_clip() checks for
priv->needs_allocation just before.
So let's just use the allocation directly here instead of going through
that function.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1264
The ABSOLUTE_ORIGIN_CHANGED allocation flag is only really useful to
propagate the information of the absolute origin of an actor having
changed inside Clutter. It wasn't used anywhere else besides for some
debug messages and it probably shouldn't be used in custom layout
implementations anyway since 1) actors shouldn't have to be aware of
absolute allocation changes and 2) it doesn't factor in changes to the
transformation matrix of a parent.
Also the propagation of absolute origin changes using this flag broke
with commit 0eab73dc2e and now hidden actors are no longer notified
about those changes.
Additionally, this flag gets in the way of a few potential optimizations
since it has to be propagated even if the allocation box of the child
hasn't changed, forcing a reallocation of the child.
So replace this flag with a simple new private property of ClutterActor
absolute_origin_changed, but keep the exact same behavior for now.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1245
Since we now only layout the children ourselves in case the actor
implementation doesn't override the allocate vfunc, we can remove
clutter_actor_maybe_layout_children() and move the functionality inside
clutter_actor_real_allocate().
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1245
Now that we no longer have the DELEGATE_LAYOUT we expect all actors
overriding the allocate() vfunc to allocate their children themselves.
Since clutter_actor_set_allocation() is only called from custom
vfunc_allocate() implementations, the condition in
clutter_actor_maybe_layout_children() would always fail, which makes
calling the function useless anyway.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1245
The CLUTTER_DELEGATE_LAYOUT flag is unintuitive and makes the allocation
process inside Clutter unnecessarily complicated. It's very easy for
actors overriding the allocate() vfunc to layout their children
themselves (in fact most of them do this), and it also never made sense
that clutter_actor_set_allocation() does eventually layout children.
There was no ClutterActor implementation in mutter or gnome-shell which
actually used the DELEGATE_LAYOUT flag, but even without it, it's fairly
easy to archive the same behavior now: In the allocate() override,
adjust the allocation as wanted, then chain up to the parent vfunc
without calling clutter_actor_set_allocation().
So remove the CLUTTER_DELEGATE_LAYOUT flag, which will allow making the
relayout code in Clutter a bit easier to follow.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1245
The public API to get the parent actor, clutter_actor_get_parent() does
a type check whether the actor is actually a ClutterActor. In case of
_clutter_actor_apply_relative_transformation_matrix(), which is called
recursively and very often during the paint process, this type check
shows up with almost twice the amount of hits than the actual matrix
multiplication.
So use the parent pointer directly in some code paths that are executed
very often and avoid the expensive type checking there, we can do that
since both places are not public API.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1259
