Keeping the backing Cairo surface of a CairoTexture canvas in sync with
the actor's allocation is tedious and prone to mistakes. We can
definitely do better by simply exposing a property that does the surface
resize and invalidation automagically on ::allocate.
The current "create context/draw/destroy context" pattern presents
various problems. The first issue is that it defers memory management to
the caller of the create() or create_region() methods, which makes
bookkeeping of the cairo_t* harder for language bindings and third party
libraries. The second issue is that, while it's easier for
draw-and-forget texturs, this API is needlessly complicated for contents
that have to change programmatically - and it introduces constraints
like calling the drawing code explicitly after a surface resize (e.g.
inside an allocate() implementation).
By using a signal-based approach we can make the CairoTexture actor
behave like other actors, and like other libraries using Cairo as their
2D drawing API.
The semantics of the newly-introduced ::draw signal are the same as the
one used by GTK+:
- the signal is emitted on invalidation;
- the cairo_t* context is owned by the actor;
- it is safe to have multiple callbacks attached to the same
signal, to allow composition;
- the cairo_t* is already clipped to the invalidated area, so
that Cairo can discard geometry immediately before we upload
the texture data.
There are possible future improvements, like coalescing multiple
invalidations inside regions, and performing clipped draws during
the paint cycle; we could even perform clipped redraws if we know the
extent of the invalidated area.
This adds a public function to get the bounds of the current clipped
redraw on a stage. This should only be called while the stage is being
painted. The function diverts to a virtual function on the
ClutterStageWindow implementation. If the function isn't implemented
or it returns FALSE then the entire stage is reported. The clip bounds
are in integer pixel coordinates in the stage's coordinate space.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2421
* swipe-action:
test-swipe-action: Clean up the test code
docs: Add the new actions to the API reference
gesture-action: Remove the multi-device entry points
swipe-action: Remove the required devices call
swipe-action: Clean up
gesture-action: Clean up
Add ClutterSwipeAction and ClutterGestureAction
This adds a virtual to ClutterActor so that an actor subclass can
report whether it has overlapping primitives. ClutterActor uses this
to determine whether it needs to use ClutterFlattenEffect to implement
the opacity property. The default implementation of the virtual
returns TRUE which means that most actors will end up being redirected
offscreen when the opacity != 255. ClutterTexture and ClutterRectangle
override this to return FALSE because they should never need to be
redirected. ClutterClone overrides it to divert to the source.
The values for the ClutterOffscreenRedirect enum have changed to:
AUTOMATIC_FOR_OPACITY
The actor will only be redirected if has_overlaps returns TRUE and
the opacity is < 255
ALWAYS_FOR_OPACITY
The actor will always be redirected if the opacity < 255 regardless
of the return value of has_overlaps
ALWAYS
The actor will always be redirected offscreen.
This means that the property can't be used to prevent the actor from
being redirected but only to increase the likelihood that it will be
redirected.
ClutterActor now adds and removes the flatten effect depending on
whether flattening is needed directly in clutter_actor_paint(). There
are new internal versions of add/remove_effect that don't queue a
redraw. This means that ClutterFlattenEffect is now just a no-op
subclass of ClutterOffscreen. It is only needed because
ClutterOffscreen is abstract. Removing the effect also makes it so
that the cached image will be freed as soon as an actor is repainted
without being flattened.
This adds a property which can be used to redirect the actor through
an FBO before painting so that it becomes flattened in an image. The
image can be used as a cache to avoid having to repaint the actor if
something unrelated in the scene changes. It can also be used to
implement correct opacity even if the actor has overlapping
primitives. The property is an enum that takes three values:
CLUTTER_OFFSCREEN_REDIRECT_NEVER: The default behaviour which is to
never flatten the actor.
CLUTTER_OFFSCREEN_REDIRECT_ALWAYS: The actor is always redirected
through an FBO.
CLUTTER_OFFSCREEN_REDIRECT_ONLY_FOR_OPACITY: The actor is only
redirected through an FBO if the paint opacity is not 255. This
value would be used if the actor wants correct opacity. It will
avoid the overhead of using an FBO whenever the actor is fully
opaque.
The property is implemented by installing a ClutterFlattenEffect.
ClutterFlattenEffect is a new internal class which subclasses
ClutterOffscreen to redirect the painting to an FBO. When
ClutterOffscreen paints, the effect sets an opacity override on the
actor so that the image will always contain the actor at full
opacity. The opacity is then applied to the resulting image before
painting it to the stage. This means the actor does not need to be
redrawn while the opacity is being animated.
The effect has a high internal priority so that it will always occur
before any other effects and it gets hidden from the application.
This adds a new public function to queue a rerun of an effect. If
nothing else queues a redraw then when the effect's actor is painted
the effect will be run without the CLUTTER_EFFECT_RUN_ACTOR_DIRTY
flag. This allows parametrised offscreen effects to report that they
need to redraw the image without having to redraw the underlying
actor. This will be used to implement the 'transparency' effect of
ClutterActor.
If multiple redraws are queued with different effects then redrawing
is started from the one that occurs last in the list of effects.
Internally the function is a wrapper around the new function
_clutter_actor_queue_redraw_full. This is intended to be the sole
point of code for queuing redraws on an actor. It has parameters for
the clip and the effect. The other two existing functions to queue a
redraw (one with a clip and one without) now wrap around this function
by passing a NULL effect.
This adds a new virtual to ClutterEffect which is intended to be a
more flexible replacement for the pre and post_paint functions. The
implementation of a run virtual would look something like this:
void
effect_run (ClutterEffect *effect,
ClutterEffectRunFlags flags)
{
/* Set up state */
/* ... */
/* Chain to the next item in the paint sequence */
clutter_actor_continue_paint (priv->actor);
/* Clean up state */
/* ... */
}
ClutterActor now just calls this virtual instead of the pre_paint and
post_paint functions. It keeps track of the next effect in the list so
that it knows what to do when clutter_actor_continue_paint is
called. clutter_actor_continue_paint is a new function added just for
implementing effects.
The default implementation of the run virtual just calls pre_paint and
post_paint so that existing effects will continue to work.
An effect is allowed to conditionally skip calling
clutter_actor_continue_paint(). This is useful to implement effects
that cache the image of an actor. The flags parameter can be used to
determine if the actor is dirty since the last paint. ClutterActor
sets this flag whenever propagated_one_redraw is TRUE which means that
a redraw for this actor or one of its children was queued.
This backend hasn't been used for years now and so because it is
untested code and almost certainly doesn't work any more it would be a
burdon to continue trying to maintain it. Considering that we are now
looking at moving OpenGL window system integration code down from
Clutter backends into Cogl that will be easier if we don't have to
consider this backend.
The OffscreenEffect class needs to expose a way for sub-classes to
track the size of FBO it creates, in case it has to do some geometry
deformations like the DeformEffect sub-classes.
Let's move the private symbol we used internally in 1.6 to fix
DeformEffect to the list of public symbols of OffscreenEffect.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2570
Creating a synthetic event requires direct access to the ClutterEvent
union members; this access does not map in bindings to high-level
languages, especially run-time bindings using GObject-Introspection.
It's also midly annoying from C, as it unnecessarily exposes the guts of
ClutterEvent - something we might want to fix in the future.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2575
Make sure users get the idea that clutter_init()
has a return value that needs to be checked.
These were fixed via sed magic:
sed -i -s -e "s/clutter_init (.*)/\
if (& != CLUTTER_INIT_SUCCESS)\n return 1/"\
doc/*/*/*.{c,xml} doc/*/*.xml
http://bugzilla.clutter-project.org/show_bug.cgi?id=2574
When synthesizing events coming from input devices it should be
possible to just call a setter function, to avoid a huge switch
on the type of the event.
Clutter should also store the device pointer inside the private
data, for faster access of the pointer in allocated events.
Finally, the get_device_id() and get_device_type() accessors should
just be wrappers around clutter_event_get_device(), to reduce the
amount of code duplication.
Allow the developer to set whether the Stage should receive key focus
when mapped. The implementation is fully backend-dependent. The default
value is TRUE because that's what we've been expecting so far.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2500
Other frameworks expose the same functionality as "auto-reverse",
probably to match the cassette tape player. It actually makes sense
for Clutter to follow suit.
