Use the internal child list for the default map/unmap vfuncs. This removes
the requirement for non-container composite actors to implement their own
map/unmap functions.
Unrealizing an actor is a recursive process that needs to traverse the
children of an actor to ensure they are also unrealized. This maintains
the invariant that if any given actor is marked as unrealized then you
know that all its children have also been unrealized.
The previous implementation would use the container interface's
foreach_with_internals vfunc to explicitly traverse the children of
container actors but this didn't consider composite actors that aren't
containers.
Since clutter-actor now maintains an explicit list of children we can
also handle composite actors that aren't containers using
_clutter_actor_traverse.
This makes it possible to choose the traversal order; either depth first
or breadth first and when visiting actors in a depth first order there
is now a callback called before children are traversed and one called
after. Some tasks such as unrealizing actors need to explicitly control
the traversal order to maintain the invariable that all children of an
actor are unrealized before we actually mark the parent as unrealized.
The callbacks are now passed the relative depth in the graph of the
actor being visited and instead of only being able to return a boolean
to bail out of further traversal it can now do one of: continue,
skip_children or break. To implement something like unrealize it's
desirable to skip children that you find have already been unrealized.
The last_paint_box for an actor represents its "normal" position - we
shouldn't update it or use it to cull drawing if we are painting
a clone of the actor. Tracking whether we are painting a clone is
done by adding _clutter_actor_push/pop_clone_paint() and a global
"clone paint level".
http://bugzilla.clutter-project.org/show_bug.cgi?id=2396
When transforming a paint-volume or transforming allocation vertices we
are transforming more than one point at a time so we can batch those
together with cogl_matrix_transform_points instead of
cogl_matrix_transform_point. Also in both of these cases we don't need
to do a projective transform so using cogl_matrix_transform_points also
lets us reduce the per-vertex computation.
The Behaviour class and its implementations have been replaced by the
new animation framework API and by the constraints for layout-related
animations.
Currently, we need to make tests build, so we undef DISABLE_DEPRECATED
in specific test cases while they get ported.
The paint volume structure is cached in the Actor it references, and
this causes a reference cycle.
The paint volume is going to be used when painting, so the actor must
still be valid - otherwise Clutter will bail out far before than
accessing the actor pointer in ClutterPaintVolume.
Otherwise, we could have used dispose() to check for a valid actor and
remove a reference if the actor field is !NULL; it feels less clean,
though, since we're effectively managing an extra reference on
ourselves.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2431
For internal usage, writing:
clutter_actor_get_name (actor) != NULL
? clutter_actor_get_name (actor)
: G_OBJECT_TYPE_NAME (actor)
is overly verbose and does two type checks. A simple, internal method
for getting the same result without type checks would be much more
appreciated.
Instead of waiting until clutter_actor_paint to check if there are any
handlers connected to the "paint" signal, we now do the check whenever
the paint-volume is requested in _actor_get_paint_volume_mutable().
Previously we checked in clutter_actor_paint(), but at that time we may
already be using a stage clip that could be derived from an invalid
paint-volume. We used to try and handle that by queuing a follow up,
unclipped, redraw but anyway there was an additional problem with the
previous approach because the checking wasn't enough to always catch
invalid volumes involved in culling (considering that containers may
derive their volume from children that haven't yet been painted)
By moving the check to _get_paint_volume time not only do we now
correctly check children in cases where a container derives its volume
from its children's volumes but we no longer need to queue follow up
redraws to cover up artefacts.
Since we now never queue follow up redraws, this in turn means we should
no longer clobber redraws queued with an explicit clip which was
something affecting gnome-shell since it connects a handler to the paint
signal of the stage.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2388
Once an actor had _clutter_stage_queue_redraw_entry_invalidate()
called on it once, then priv->queue_redraw_entry would point to
an entry with entry->actor NULL. _clutter_stage_queue_actor_redraw()
doesn't handle this case and no further redraws would be queued.
To fix this, NULL out priv->queue_redraw_entry() and then make sure
we free the invalidated entry in
_clutter_stage_maybe_finish_queue_redraws() just as we do for
still valid entries.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2389
We need to make sure that redraws queued for actors on a stage are for
actors actually in the stage. So in clutter_actor_unparent() descend
through the children and remove redraws. Just removing the actor itself
isn't good enough since an entire hierarchy can be removed from the
stage without breaking it up into individual actors.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2359
This is based on an original patch from Owen Taylor who debugged the
root cause of this bug; thanks.
Instead of delegating the check for the ActorMeta:enabled property to
the sub-classes of ClutterActorMeta, ClutterActor can do the check prior
to using the ClutterActorMeta instances.
In all the changes made recently to how we handle redraws and adding
support for paint-volumes we stopped looking at explicit clip regions
passed to _clutter_actor_queue_redraw_with_clip.
In _clutter_actor_finish_queue_redraw we had started always trying to
clip the redraw to the paint-volume of the actor, but forgot to consider
that the user may have already determined the clip region for us!
Now we first check if the given clip != NUll and if so we don't need to
calculate the paint-volume of the actor.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2349
Since re-working how redraws are queued it is no longer necessary to
dirty the pick buffer in _clutter_actor_real_queue_redraw since this
should now reliably be handled in _clutter_stage_queue_actor_redraw.
This adds two internal functions relating to explicit traversal of the
scenegraph:
_clutter_actor_foreach_child
_clutter_actor_traverse
_clutter_actor_foreach_child just iterates the immediate children of an
actor, and with a new ClutterForeachCallback type it allows the
callbacks to break iteration early.
_clutter_actor_traverse traverses the given actor and all of its
decendants. Again traversal can be stopped early if a callback returns
FALSE.
The first intended use for _clutter_actor_traverse is to maintain a
cache pointer to the stage for all actors. In this case we will need to
update the pointer for all descendants of an actor when an actor is
reparented in any way.
This adds a private getter to query the number of children an actor has.
One use planned for this API is to avoid calling get_paint_volume on
such actors. (It's not clear what the best semantics for
get_paint_volume are for actors with children, so we are considering
leaving the semantics undefined for the initial clutter 1.4 release)
We now explicitly track the list of children each actor has in a private
GList. This gives us a reliable way to know how many children an actor
has - even for composite actors that don't implement the container
interface. This also will allow us to directly traverse the scenegraph
in a more generalized fashion. Previously the scenegraph was
more-or-less represented implicitly according the implementation of
paint methods.
When using the CLUTTER_PAINT=paint-volumes debug option we try and show
when a paint volume couldn't be determined by drawing a blue outline of
the allocation instead. There was a typo though and instead we were
drawing an outline the size of the stage instead of for the given actor.
This fixes that and removes a FIXME comment relating to the blue outline
that is now implemented.
This reverts commit ca44c6a7d8abe9f2c548bee817559ea8adaa7a80.
In reality there are probably lots of actors that depend on the exact
semantics as they are documented so this change isn't really acceptable.
For example when the font changes in ClutterText we only queue a
relayout, and since it's possible that the font will have the same size
and the actor won't get a new allocation it wouldn't otherwise queue a
redraw.
Since queue_redraw requests now get deferred until just before a paint
run it is actually no longer a problem to queue the redraw here.
Instead of immediately, recursively emitting the "queue-redraw" signal
when clutter_actor_queue_redraw is called we now defer this process
until all stage updates are complete. This allows us to aggregate
repeated _queue_redraw requests for the same actor avoiding redundant
paint volume transformations. By deferring we also increase the
likelihood that the actor will have a valid paint volume since it will
have an up to date allocation; this in turn means we will more often be
able to automatically queue clipped redraws which can have a big impact
on performance.
Here's an outline of the actor queue redraw mechanism:
The process starts in clutter_actor_queue_redraw or
_clutter_actor_queue_redraw_with_clip.
These functions queue an entry in a list associated with the stage which
is a list of actors that queued a redraw while updating the timelines,
performing layouting and processing other mainloop sources before the
next paint starts.
We aim to minimize the processing done at this point because there is a
good chance other events will happen while updating the scenegraph that
would invalidate any expensive work we might otherwise try to do here.
For example we don't try and resolve the screen space bounding box of an
actor at this stage so as to minimize how much of the screen redraw
because it's possible something else will happen which will force a full
redraw anyway.
When all updates are complete and we come to paint the stage (see
_clutter_stage_do_update) then we iterate this list and actually emit
the "queue-redraw" signals for each of the listed actors which will
bubble up to the stage for each actor and at that point we will
transform the actors paint volume into screen coordinates to determine
the clip region for what needs to be redrawn in the next paint.
Note: actors are allowed to queue a redraw in reseponse to a
queue-redraw signal so we repeat the processing of the list until it
remains empty. An example of when this happens is for Clone actors or
clutter_texture_new_from_actor actors which need to queue a redraw if
their source queues a redraw.
This makes clutter_actor_queue_redraw simply bail out early if the actor
isn't a descendant of a ClutterStage since the request isn't meaningful
and it avoids a crash when trying to queue a clipped redraw against the
stage to clear the actors old location.
This splits out all the clutter_paint_volume code from clutter-actor.c
into clutter-paint-volume.c. Since clutter-actor.c and
clutter-paint-volume.c both needed the functionality of
_fully_transform_vertices, this function has now been moved to
clutter-utils.c as _clutter_util_fully_transform_vertices.
There are too many examples where the default assumption that an actor
paints inside its allocation isn't true, so we now return FALSE in the
base implementation instead. This means that by default we are saying
"we don't know the paint volume of the actor", so developers need to
implement the get_paint_volume virtual to take advantage of culling and
clipped redraws with their actors.
This patch provides very conservative get_paint_volume implementations
for ClutterTexture, ClutterCairoTexture, ClutterRectangle and
ClutterText which all explicitly check the actor's object type to avoid
making any assumptions about subclasses.
We were always explicitly checking priv->needs_allocation in
_clutter_actor_queue_redraw_with_clip, but we only need to do that if
the CLUTTER_REDRAW_CLIPPED_TO_ALLOCATION flag is used.
This initializes priv->last_paint_box with a degenerate box, so a newly
allocated actor added to the scenegraph and made visible only needs to
trigger a redraw of its initial position. If we don't have a valid
last_paint_box though we would instead trigger a full stage redraw.
To make comparing the performance with culling/clipped redraws
enabled/disabled fairer we now avoid querying the paint box when they
are disabled, so that results should reflect how the cost of
transforming paint volumes into screen space etc gets offset against the
benefit of culling.
We have bent the originally documented semantics a bit so now where we
say "Queueing a new layout automatically queues a redraw as well" it
might be clearer to say "Queuing a new layout implicitly queues a redraw
as well if anything in the layout changes".
This should be close enough to the original semantics to not cause any
problems.
Without this change then we we fail to take advantage of clipped redraws
in a lot of cases because queuing a redraw with priv->needs_allocation
== TRUE will automatically be promoted to a full stage redraw since it's
not possible to determine a valid paint-volume.
Also queuing a redraw here will end up registering a redundant clipped
redraw for the current location, doing quite a lot of redundant
transforms, and then later when re-allocated during layouting another
queue redraw would happen with the correct paint-volume.
This uses actor paint volumes to perform culling during
clutter_actor_paint.
When performing a clipped redraw (because only a few localized actors
changed) then as we traverse the scenegraph painting the actors we can
now ignore actors that don't intersect the clip region. Early testing
shows this can have a big performance benefit; e.g. 100% fps improvement
for test-state with culling enabled and we hope that there are even much
more compelling examples than that in the real world,
Most Clutter applications are 2Dish interfaces and have quite a lot of
actors that get continuously painted when anything is animated. The
dynamic actors are often localized to an area of user focus though so
with culling we can completely avoid painting any of the static actors
outside the current clip region.
Obviously the cost of culling has to be offset against the cost of
painting to determine if it's a win, but our (limited) testing suggests
it should be a win for most applications.
Note: we hope we will be able to also bring another performance bump
from culling with another iteration - hopefully in the 1.6 cycle - to
avoid doing the culling in screen space and instead do it in the stage's
model space. This will hopefully let us minimize the cost of
transforming the actor volumes for culling.
This makes clutter_actor_queue_redraw transparently use an actor's paint
volume to queue a clipped redraw.
We save the actors paint box each time it is painted so that when
clutter_actor_queue_redraw is called we can determine the old and new
location of the actor so we know the full bounds of what must be redrawn
to clear its old view and show the new.
This makes _clutter_actor_transform_and_project_box a static function
and removes the prototype from clutter-private.h since it is no longer
used outside clutter-actor.c
