It should be possible to ask a timeline what is its duration, taking
into account eventual repeats, and which repeat is the one currently
in progress.
These two functions allow writing animations that depend on the current
state of another timeline.
It should be possible to set up the delay of a transition, but since
we start the Transition instance before returning control to the caller,
we cannot use clutter_actor_get_transition() to do it without something
extra-awkward, like:
transition = clutter_actor_get_transition (actor, "width");
clutter_timeline_stop (transition);
clutter_timeline_set_delay (transition, 1000);
clutter_timeline_start (transition);
for each property involved. It's much easier to add a delay to the
easing state of an actor.
Clutter is meant to be, and I quote from the README, a toolkit:
for creating fast, compelling, portable, and dynamic graphical
user interfaces
and yet the default mode of operation for setting an actor's state on
the scene graph (position, size, opacity, rotation, scaling, depth,
etc.) is *not* dynamic. We assume a static UI, and then animate it.
This is the wrong way to design an API for a toolkit meant to be used to
create animated user interfaces. The default mode of operation should be
to implicitly animate every state transition, and only allow skipping
the animation if the user consciously decides to do so — i.e. the design
tenet of the API should be to make The Right Thing™ by default, and make
it really hard (or even impossible) to do The Wrong Thing™.
So we should identify "animatable" properties, i.e. those properties
that should be implicitly animated by ClutterActor, and use the
animation framework we provide to tween the transitions between the
current state and the desired state; the implicit animation should
happen when setting these properties using the public accessors, and not
through some added functionality. For instance, the following:
clutter_actor_set_position (actor, newX, newY);
should not make the actor jump to the (newX, newY) point; it should
tween the actor's position between the current point and the desired
point.
Since we have to maintain backward compatibility with existing
applications, we still need to mark the transitions explicitly, but we
can be smart about it, and treat transition states as a stack that can
be pushed and popped, e.g.:
clutter_actor_save_easing_state (actor);
clutter_actor_set_easing_duration (actor, 500);
clutter_actor_set_position (actor, newX, newY);
clutter_actor_set_opacity (actor, newOpacity);
clutter_actor_restore_easing_state (actor);
And we can even start stacking animations, e.g.:
clutter_actor_save_easing_state (actor);
clutter_actor_set_easing_duration (actor, 500);
clutter_actor_set_position (actor, newX, newY);
clutter_actor_save_easing_state (actor);
clutter_actor_set_easing_duration (actor, 500);
clutter_actor_set_easing_mode (actor, CLUTTER_LINEAR);
clutter_actor_set_opacity (actor, newOpacity);
clutter_actor_set_depth (actor, newDepth);
clutter_actor_restore_easing_state (actor);
clutter_actor_restore_easing_state (actor);
And so on, and so forth.
The implementation takes advantage of the newly added Transition API,
which uses only ClutterTimeline sub-classes and ClutterInterval, to cut
down the amount of signal emissions and memory management of object
instances; as well of using the ClutterAnimatable interface for custom
properties and interpolation of values.
As a convenience for the C API.
Language bindings should already be using the GValue variants.
This commit also moves the custom progress functions out of the
clutter-interval.c, as they are meant to be generic interpolation
functions and not ClutterInterval-specific.
The ::paint, ::queue-redraw, and ::queue-relayout signals should be
marked as no-recurse and no-hooks; these signals are emitted *a lot*
during each frame, and since GLib has a bunch of optimizations for
signals with no closures, we should try and squeeze every single CPU
cycle we can.
Dist clutter-version.h for use under non-autotools-based build
environments (e.g. MSVC) as this header is now generic under the
systems Clutter supports
Checked with Emmanuele Bassi on IRC.
The frame_budget member of ClutterMasterClock is only enabled when
CLUTTER_ENABLE_DEBUG is enabled, so fix the build with this.
Checked with Emmanuele Bassi on IRC.
Normally this leak goes unnoticed because basic fundamental types
are typically used with clutter_actor_animate(), the leak shows up
if boxed or object types are passed (such as ClutterVertex in the
case I stumbled upon).
The ClutterBrightnessContrastEffect effect class allows changing the
brightness and contrast levels of an actor.
Modified-by: Emmanuele Bassi <ebassi@linux.intel.com>
Modified-by: Neil Roberts <neil@linux.intel.com>
https://bugzilla.gnome.org/show_bug.cgi?id=656156
We can use the __COUNTER__ macro or, failing that, the __LINE__ macro to
ensure that we don't declare dummy variables more than once with the
same name.
The comment says that we're going to load textures in a loop until we
still have work to do, or if one iteration took more than 5
milliseconds, to avoid blowing up our frame budget, but the check is for
5 seconds, which is hardly a sensible value.
We remove 2 pixels from the height of the cursor, but we should also
remove the same amount from the position on the y axis, so that the
cursor caret appears centered in the allocated height.
https://bugzilla.gnome.org/show_bug.cgi?id=655491
ClutterScript should be able to automatically call gettext() and friends
on strings loaded from a UI definition, prior to passing the string to
the object it is constructing.
The basic implementation is trivial:
- set a translation domain on the ClutterScript instance
- mark the translatable strings inside the JSON data, like:
"property" : {
"translatable" : true,
"string" : "a translatable string"
}
The hard part is now getting the tools we use to extract the
translatable strings to understand the JSON format we use inside
ClutterScript.
Let's keep a budget of 16.6 milliseconds per frame, and reduce it by the
amount of time spent in each phase of the frame processing. If any phase
goes over the allocated budget then we use the diagnostic mode
facilities to warn the app developer.
It is sometimes useful to be able to have better control on when a
repaint function is called. Currently, all repaint functions are called
prior to the stages update phase of the frame processing.
We can introduce flags to represent the point in the frame update
process in which we wish Clutter called the repaint function.
As a bonus, we can also add a flag that causes adding a repaint function
to spin the master clock.
In theory, handlers connected to the ::allocation-changed signal may be
able to modify the actor's real allocation and allocation flags,
especially now that we use STATIC_SCOPE; let's avoid this, so that we
don't regret it later.
The show and hide implementation inside ClutterStage ended up being
recursive, and the hide implementation would actually show the children
of the stage unconditionally.
Whoopsie.
The ActorBox passed to the ::allocation-changed signal should be
annotated as STATIC_SCOPE, given that it's a pointer to a structure
inside ClutterActorPrivate - hence there's no risk of it actually being
freed from a signal handler. This allows the GSignal machinery to avoid
a costly copy/free for each signal emission.
If the redraw entry is not cleared, queueing a redraw from a signal
handler could reinsert the same object in the stage redraw list,
causing the segfault later (as the object is immediately freed)
https://bugzilla.gnome.org/show_bug.cgi?id=671173
This just adds some padding pointers so that we can later add more
virtual functions without breaking ABI.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
Clutter applications using evdev are typically fullscreen applications
associated with a single virtual termainal. When switching away from
the applications associated tty then Clutter should stop managing all
evdev devices and re-probe for devices when the application regains
focus by switching back to the tty. To facilitate this, this patch
adds clutter_evdev_release_devices() and clutter_evdev_reclaim_devices()
functions.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
When using the Wayland backend this sets a constraint that the
CoglRenderer selects the Wayland EGL winsys.
When a Wayland compositor display is set it now also sets a constraint
that the render should use EGL because only EGL renderers will set up
the required wl_drm global object.
The X11 backend now sets the X11 constraint.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
The core input devices when XInput doesn't work were being created as
generic ClutterInputDevices instead of ClutterInputDeviceX11s. This
meant the keycode_to_evdev virtual wouldn't work.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds a virtual function to ClutterInputDevice to translate a
keycode from the hardware_keycode member of ClutterKeyEvent to an
evdev keycode. The function can fail so that input backends that don't
have a sensible way to translate to evdev keycodes can return FALSE.
There are implementations for evdev, wayland and X. The X
implementation assumes that the X server is using an evdev driver in
which case the hardware keycodes are the evdev codes plus 8.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
Because evdev isn't associated with the display system, it doesn't
have any easy way to associate an input device with a stage.
Previously Clutter would never set a stage for an input device and
leave it up to the application to set it. To make it easier for
applications which just have a single fullscreen stage (which is
probably the most common use case for evdev) the device manager now
associates all input devices with the first stage that is created
unless something has already set a stage.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
The shm buffer format enum values were renamed and the explicitly
premultiplied format was dropped since it's now assumed if the buffer
has an alpha component then it's premultiplied.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
The pick method doesn't do anything special over the default pick
method provided by ClutterActor so there's no need to implement it.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds a signal that's emitted whenever a wayland surface is damaged
that allows sub-classes to override the default handler to change
how clipped redraws are queued if the sub-class doesn't simply draw
a rectangle. The signal can also be used just to track damage.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds a "cogl-texture" gobject property so that a compositor may
listen for notifications of changes to the texture used to paint.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
This patch renames the width/height properties to
surface-width/surface-height so that they won't override the
width/height properties of ClutterActor which have different
semantics.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds a NEEDS_XKB_UTILS automake conditional that's set to true if
either the wayland backend is enabled or the evdev input backend is
enabled since they both depend on clutter-xkb-utils.c and we need
to avoid listing the file twice since that leads to duplicate symbols
and the build fails.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
When a new buffer is attached and we update the width and height
properties for the surface we now also call clutter_actor_set_size()
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
This adds a clutter_wayland_surface_get_surface() function for querying
the struct wl_surface * associated with a ClutterWaylandSurface.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
This exposes a clutter_wayland_surface_set_surface() function. The
implementation ignores requests to re-set the same surface and since now
has code to cleanup old surface state before setting the new surface.
(previously the surface was construct only so this wasn't necessary)
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
When disposing a ClutterWaylandSurface we now make sure to unref any
pipeline we created and unref any surface buffer textures we created.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
There was a GArray member named damage that wasn't being used which this
patch removes.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
If wayland compositor support has been enabled then we make sure to
install the corresponding public headers and a
clutter-wayland-compositor.pc pkgconfig file.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
We currently check for the IN_DESTRUCTION flag inside the
add_child_internal() function.
This check disallows calling methods that change the stacking order
within the destruction sequence, by triggering a critical warning first,
and leaving the actor in an undefined state, which then ends up being
caught by an assertion.
The reproducible sequence is:
- actor gets destroyed;
- another actor, linked to the first, will try to change the
stacking order of the first actor;
- changing the stacking order is a composite operation composed
by the following steps:
1. ref() the child;
2. remove_child_internal(), which removes the reference;
3. add_child_internal(), which adds a reference;
- the state of the actor is not changed between (2) and (3), as
it could be an expensive recomputation;
- if (3) bails out, then the actor is in an undefined state, but
still alive;
- the destruction sequence terminates, but the actor is unparented
while its state indicates being parented instead.
- assertion failure.
The obvious fix would be to decompose each set_child_*_sibling() method
into proper remove_child()/add_child(), with state validation; this may
cause excessive work, though, and trigger a cascade of other bugs in
code that assumes that a change in the stacking order is an atomic
operation.
Another potential fix is to just remove this check here, and let code
doing stacking order changes inside the destruction sequence of an actor
continue doing the work.
The third fix is to silently bail out early from every
set_child_*_sibling() and set_child_at_index() method, and avoid doing
work.
I have a preference for the second solution, since it involves the least
amount of work, and the least amount of code duplication.
See bug: https://bugzilla.gnome.org/show_bug.cgi?id=670647
This solves a crash on GNOME Shell, as compute the extents
for some StWidgets could lead to call st_widget_get_theme_node,
and it is a fatal error to call this on a widget that it not
beed added to a stage.
Make it like the clutter-version.h.in template. Since we aren't having
Windows-specific items in here (such as CLUTTER_FLAVOUR), perhaps we
could get the dllexport stuff in clutter-version.h.in, where it can be
used when necessary, and this file would be gone.
GLib introduced macros that allows defining the lower and upper bounds
of the API to be used by application code.
The lower bound allows to define the minimum version that will trigger
deprecation warnings; the upper bound defines the maximum version that
will trigger compiler warnings for unavailable symbols.
This scheme allows gradually porting application code to a new version
of the API, especially in case of resynchronization after multiple
development cycles.
Now that ClutterActor has a default paint volume, subclasses may wish
to retrieve it without chaining up to the parent's implementation of
the get_paint_volume() function.
The get_default_paint_volume() returns a ClutterPaintVolume pointer
to the paint volume as computed by the default implementation of the
get_paint_volume() virtual function; it can only be used immediately,
as it's not guaranteed to survive across multiple frames.
Creating PaintVolume instances is not possible, and it's not recommended
anyway. It is, though, necessary to union paint volumes, especially with
2D boxes, in some cases.
Clutter should provide a simple convenience function that allows
unioning volumes to boxes in a moderately efficient way.
https://bugzilla.gnome.org/show_bug.cgi?id=670021
It should be possible to adapt the abicheck.sh script so that it
actually tests the ABI of libclutter-1.0.so taking into account
the backends that were compiled into Clutter, and avoid expected
failures if Clutter was not built with a specific backend.
https://bugzilla.gnome.org/show_bug.cgi?id=670680
We cannot deprecate ClutterAlpha yet. We cannot also implement
ClutterAlpha in terms of ClutterTimeline, because multiple Alpha
instances can be attached to the same Timeline. So we can start
with a "soft" deprecation: just a warning in the documentation
stating that ClutterAlpha will be deprecated, and removed, in the
future, and that newly-written code should use ClutterTimeline
instead.
We can use ClutterTimeline and its progress mode inside
ClutterAnimation; obviously, we have to maintain the invariants because
of the ClutterAnimation:alpha property, but if all you set is the :mode
property using one of the Clutter animation modes then we can skip the
ClutterAlpha entirely.
Instead of having the easing functions be dependent of ClutterAlpha, and
static to the clutter-alpha.c source file, we should make them generic
and move them to their own internal header and source files. This will
allow to re-use them in the near future.
Since Cogl has started restricting what cogl 1.x api is exposed when
COGL_ENABLE_EXPERIMENTAL_2_0_API is defined and since we build all
Clutter internals with COGL_ENABLE_EXPERIMENTAL_2_0_API defined this
patch makes a first pass at reducing our internal use of the Cogl 1.x
api.
The most notable api that's no longer exposed to us internally is
the cogl_material_ api so this switches all Clutter internals to use the
cogl_pipeline_ api instead. This patch also makes quite a bit of
progress removing internal uses of CoglHandle although there is still
more to go.
The experimental cogl_texture_pixmap_x11_new() api was recently changed
to take an explicit context argument and return a GError on failures.
This updates Clutter's use of the api accordingly.
We were only exposing clutter_backend_get_cogl_context() if
COGL_ENABLE_EXPERIMENTAL_2_0_API had been defined but the CoglContext
api is also available if COGL_ENABLE_EXPERIMENTAL_API has been defined.
As it was it meant that code opting into the experimental Cogl api
but not limiting to the 2.0 only api would have to #define
COGL_ENABLE_EXPERIMENTAL_2_0_API before including clutter.h but make
sure it wasn't defined when including cogl.h which was particularly
awkward.
Recently the cogl_framebuffer_swap_* apis were moved into the
cogl_onscreen_* namespace since only CoglOnscreen framebuffers can be
double buffered. This renames all uses of the cogl_framebuffer_swap_*
apis in Clutter.
The experimental cogl_pipeline_new() api was recently changed so it
explicitly takes a CoglContext. This updates all calls to
cogl_pipeline_new() in clutter accordingly.
ATK_ROLE_CANVAS is not a suitable role, as the user (in general) can't
draw on the Stage. CallyStage implements AtkWindow, so the proper role
is ATK_ROLE_WINDOW
Removing atkcomponent, focus_tracker, etc. Emitting focus state change
from the stage. Now things are more simple, and stop to use some
of the soon-to-be-deprecated signals on ATK.
It should be possible to do:
clutter_stage_set_fullscreen (stage, TRUE);
clutter_actor_show (stage);
and have the stage be full screen as soon as it is shown.
Currently, we need to call clutter_actor_realize() prior to calling
set_fullscreen(), otherwise the backing X window will not be set,
and ClutterStageX11 will silently discard the change.
If set_fullscreen() was called prior to realization, ClutterStageX11
should delay setting the fullscreen hint until the realize() chain
has been successfully executed.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2515
If you execute the following sequence :
stage = clutter_stage_new ();
clutter_actor_set_size (stage, 1280, 800);
clutter_actor_realize (stage);
Then you end up creating an onscreen buffer of size 1280x800 but
ClutterStageX11 storing the stage size at 640x480.
This patch resync the 2 implementation by using the ClutterStage's
size in both classes when realizing.
Signed-off-by: Lionel Landwerlin <llandwerlin@gmail.com>
https://bugzilla.gnome.org/show_bug.cgi?id=667540
Unconditionally creating CoglPipeline and CoglSnippets inside the class
initialization functions does not seem to be enough when dealing with
headless builds.
Our last resort is to lazily create the base pipeline the first time we
try to copy it, during the instance initialization.
The class initialization function may be called when Clutter hasn't been
fully initialized — for instance, when scanning the source with gtk-doc
or with the introspection scanner.
The allocation code for BoxLayout contains a sequence of brain farts
that make it barely working since the synchronization of the layout
algorithm to the one in GtkBox.
The origin of the layout is inverted, and it doesn't take into
consideration a modified allocation origin (for actors the provide
padding or margin).
The pack-start property is broken, and it only works because we walk the
children list backwards; this horribly breaks when a child changes
visibility. Plus, we count invisible children, which leads to
allocations getting insane origins (either close to -MAX_FLOAT or
MAX_FLOAT).
Finally, the allocation is applied twice even for non-animated cases.
https://bugzilla.gnome.org/show_bug.cgi?id=669291
* clutter_wayland_input_device_get_wl_input_device for the input device
* clutter_wayland_stage_get_wl_surface for the Wayland surface
* clutter_wayland_stage_get_wl_shell_surface for the shell surface
This converts the blur, colorize and desaturate effects to use
snippets instead of CoglPrograms. Cogl can handle the snippets much
more efficiently than programs so this should be a performance win. It
also fixes the problem that Cogl would end up recompiling the program
for every instance of the effects because Clutter was not reusing the
same program.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
The blur effect needs to pass a uniform to the GLSL shader so that it
can know the texture coordinate offset from one texel to another. To
calculate this the blur effect was previously using the allocation
size of the actor rounded up to the next power of two. Presumably the
assumption was that Cogl would round up the size of the texture to the
next power of two when allocating the texture. However this is not be
true if the driver supports NPOT textures. Also it doesn't take into
account the paint volume of the actor which may cause the texture to
be a completely different size. This patch just changes to directly
use the size of the texture.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
Sometimes a subclass of ClutterOffscreenEffect wants to paint with a
completely custom material. In that case it is awkward to modify the
material returned owned by ClutterOffscreenEffect so it makes more
sense to just get the texture and manage its own material.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
All of the pipelines used for ClutterTexture actors share a common
pipeline ancestor created with cogl_pipeline_copy. Previously this
ancestor had a dummy 1x1 texture attached to it so that it would end
up with the same state as the child pipelines that will render with a
texture. Cogl now has a mechanism to specify that a texture will be
used with a pipeline layer without having to create an actual texture.
This patch makes it use that to avoid having an unused texture.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
If we have N children and the user passes N (or a number beyond N) to
clutter_actor_insert_child_at_index, we should respond by adding the
child at the end, not silently doing nothing.
This should avoid trying to fix the origin of a paint volume set from
the allocation's origin, and thus breaking everything.
A PaintVolume for an actor is defined to be relative to the actor's
modelview unless specifically modified by internal functions; the origin
of an actor's allocation is, on the other hand, parent-relative.
There are times when we don't want to remove all children and count of
the reference count to drop to 0 to ensure destruction; there are cases,
such as managed environments, where it's preferable to ensure that the
children of an actor get actually destroyed.
ClutterActor has a background-color property, now; we should use it for
the Stage, re-implement the color property in terms of background-color.
and deprecate the Stage property.
Being able to easily set the number of repeats has been a request for
the animation framework for some time now. The usual way to implement
this is: connect to the ::completed signal, use a static counter, and
stop the timeline when the counter hits a specific spot.
In the same light as the :auto-reverse property, we can make it easier
to implement this common functionality by adding a :repeat-count
property that, when set, limits the amount of loops that a Timeline can
perform before stopping itself.
In fact, we can implement the :loop property in terms of the
:repeat-count property just by using a sentinel value mapping to
"infinity", and map loop=FALSE to repeat-count=0, and loop=TRUE to
repeat-count=-1.
The clutter_timeline_clone() method was a pretty dumb idea when it was
introduced, back when we still had the ClutterEffectTemplate and the
clutter_effect_* animation API. It has since become an API wart: we
cannot change or add new properties to be cloned without the risk of
breaking existing code. All in all, cloning a GObject is just a matter
of calling g_object_new() with the wanted properties.
Let's deprecate this throwback of the Olden Days™, so that we can remove
it for good once we break for 2.0.
When the ClutterTextBuffer support inside ClutterText was merged, it
introduced a regression that was identified and fixed in bug 659116.
The optimization to not paint empty ClutterText actors is only valid
is the actor is not editable, or if the cursor is not visible.
Courtesy of GLib and GTK+. The abicheck.sh is a simple, Linux-only,
script to check that we're not leaking private symbols, or that the
clutter.symbols file hasn't been updated.
In theory, it should go inside the distcheck phase.
A bunch of private symbols have escaped into the SO; let's rectify this
situation by using the '_' private prefix, or making them static as they
should have been.
Cogl now requires that all applications integrate their main loop with
Cogl so that it can listen for events from winsys. This patch just
adds Cogl's GSource to the main loop.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
Reviewed-by: Robert Bragg <robert@linux.intel.com>
Some of Cogl's experimental apis have changed so that the buffer apis
now need to be passed a context argument and some drawing apis have been
replaced with cogl_framebuffer_ drawing apis that take explicit
framebuffer and pipeline arguments.
These changes were made as part of Cogl moving towards a more stateless
api that doesn't rely on a global context.
This patch updates Clutter to work with the latest Cogl api and bumps
the required Cogl version to 1.9.5.
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
Reviewed-by: Neil Roberts <neil@linux.intel.com>
Similar to the clutter_actor_iter_remove(), but it'll call destroy()
instead of remove_child().
We can also reimplement the ::destroy default handler using it, and make
it more compact.