We want to set the default size without triggering the layout machinary,
so change the window creation process slightly so we start with a
640x480 window.
Due to the way the new sizing works, clutter stage must set its size in
init (to maintain old behaviour) and the properties on the X11 stage
must be initialised to 1x1 so that it actually goes ahead with the
resize.
Fixes stages that aren't user resizable and have no size set from
appearing at 1x1.
Calling clutter_actor_set_size in response to ConfigureNotify makes
setting the size of the stage racy - the most common result of which
seems to be that you can't set the stage dimensions to anything less
than 640x480.
Instead, add a first_allocation bit to the private structure of the X11
stage and force the first resize (necessary or the default stage will be
a 1x1 window).
Now that we have a minimum size getter on the stage object, change
get_geometry to actually always return the geometry. This fixes stages
that are set as user-resizable appearing at 1x1 size.
This will need changing in other back-ends too.
Since asking for ARGB by default is still somewhat experimental on X11
and not every toolkit or complex widgets (like WebKit) still do not like
dealing with ARGB visuals, we should switch back to RGB by default - now
that at least we know it works.
For applications (and toolkit integration libraries) that want to enable
the ClutterStage:use-alpha property there is a new function:
void clutter_x11_set_use_argb_visual (gboolean use_argb);
which needs to be called before clutter_init().
The CLUTTER_DISABLE_ARGB_VISUAL environment variable can still be used
to force this value off at run-time.
If a Stage has been set to use a foreign Window then Clutter should not
be managing it; calling XWithdrawWindow and XMapWindow should be
reserved to the windows we manage ourselves.
This ensures that glViewport is called before the first stage paint.
Previously _clutter_stage_maybe_setup_viewport (which is done before we
start painting) was bailing out without calling cogl_setup_viewport because
the CLUTTER_STAGE_IN_RESIZE flag may be set if the stage was resized before
the first paint. (NB: The CLUTTER_STAGE_IN_RESIZE flag isn't removed until
we get an explicit event back from the X server since the window manager may
choose to deny/alter the resize.)
We now special case the first resize - where the viewport hasn't previously
been initialized and use the requested geometry to initialize the
glViewport without waiting for a reply from the server.
The only backend that tried to implement offscreen stages was the GLX backend
and even this has apparently be broken for some time without anyone noticing.
The property still remains and since the property already clearly states that
it may not work I don't expect anyone to notice.
This simplifies quite a bit of the GLX code which is very desireable from the
POV that we want to start migrating window system code down to Cogl and the
simpler the code is the more straight forward this work will be.
In the future when Cogl has a nicely designed API for framebuffer objects then
re-implementing offscreen stages cleanly for *all* backends should be quite
straightforward.
The user-initiated resize is conflicting with the allocated size. This
happens because we change the size of the stage's X Window behind the
back of the size allocation machinery.
Instead, we should change the size of the actor whenever we receive a
ConfigureNotify event to reflect the new size of the actor.
We force the redraw before mapping, in the hope that when a composited
window manager maps the window it will have its contents ready; that is
not going to work: the solution for this problem requires the implementation
of a protocol for compositors, and not a hack.
Moreover, painting before mapping will cause a paint with the wrong
GL viewport size, which is the wrong thing to do on GLX.
Instead of using ClutterActor for the base class of the Stage
implementation we should extend the StageWindow interface with
the required bits (geometry, realization) and use a simple object
class.
This require a wee bit of changes across Backend, Stage and
StageWindow, even though it's mostly re-shuffling.
First of all, StageWindow should get new virtual functions:
* geometry:
- resize()
- get_geometry()
* realization
- realize()
- unrealize()
This covers all the bits that we use from ClutterActor currently
inside the stage implementations.
The ClutterBackend::create_stage() virtual function should create
a StageWindow, and not an Actor (it should always have been; the
fact that it returned an Actor was a leak of the black magic going
on underneath). Since we never guaranteed ABI compatibility for
the Backend class, this is not a problem.
Internally to ClutterStage we can finally drop the shenanigans of
setting/unsetting actor flags on the implementation: if the realization
succeeds, for instance, we set the REALIZED flag on the Stage and
we're done.
As an initial proof of concept, the X11 and GLX stage implementations
have been ported to the New World Order(tm) and show no regressions.
Clutter advertises itself on X11 as implementing the _NET_WM_PING protocol,
which is needed to be able to detect frozen applications; this allows us to
stop the destruction of the stage by blocking the CLUTTER_DELETE event and
wait for user feedback without the Window Manager thinking that the app has
gone unresponsive.
In order to implement the _NET_WM_PING protocol properly, though, we need
to add the _NET_WM_PID property on the Stage window, since the EWMH states:
[_NET_WM_PID] MAY be used by the Window Manager to kill windows which
do not respond to the _NET_WM_PING protocol.
Meaning that an unresponsive Clutter application might not be killable by
the window manager.
Fixes bug:
http://bugzilla.openedhand.com/show_bug.cgi?id=1748
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
The fix for bug 1750 inside commit b190448e made Clutter-GTK spew
BadWindow errors. The reason for that is that we call XDestroyWindow()
without checking if the old Window is None; this happens if we call
clutter_x11_set_stage_foreign() on a new ClutterStage before it has
been realized.
Since Clutter-GTK does not need to realize the Stage it is going to
embed anymore (the only reason for that was to obtain a proper Visual
but now there's ClutterBackendX11 API for that), the set_stage_foreign()
call is effectively setting the StageX11 Window for the first time.
When we replace the stage Window using a foreign one we also need to
destroy the Window we created, if needed, to avoid leaking resources
all around.
Fixes bug:
http://bugzilla.openedhand.com/show_bug.cgi?id=1750
A lot of applications change the size of the stage from the default
before the stage is initially shown. The size change won't take affect
until the first allocation run. However we want the window to be at
the correct size when we first map it so we should force an allocation
run before showing the stage.
There was an explicit call to XResizeWindow in
clutter_stage_x11_show. This is not needed anymore because
XResizeWindow will already have been called by the allocate method.
Updating the WM hints on the stage window shortcircuits if the stage
is in WITHDRAWN state, so we need to move the update_wm_hints() call
after the flag has been unset.
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
The race we were experiencing in the X11 backends is apparently
back after the fix in commit 00a3c698.
This time, just delaying the setting of the SYNC_MATRICES flag
is not enough, so we can resume the use of a STAGE_IN_RESIZE
private flag.
This should also fix bug:
http://bugzilla.openedhand.com/show_bug.cgi?id=1668
The clutter_context_get_default() function is private, but shared
across Clutter. For this reason, it should be prefixed by '_' so
that the symbol is hidden from the shared object.
The :fullscreen property is very much confusing as it is implemented.
It can be written to a value, but the whole process might fail. If we
set:
g_object_set (stage, "fullscreen", TRUE, NULL);
and the fullscreen process fails or it is not implemented, the value
will be reset to FALSE (if we're lucky) or left TRUE (most of the
times).
The writability is just a shorthand for invoking clutter_stage_fullscreen()
or clutter_stage_unfullscreen() depending on a boolean value without
using an if.
The :fullscreen property also greatly confuses high level languages,
since the same symbol is used:
- for a method name (Clutter.Stage.fullscreen())
- for a property name (Clutter.Stage.fullscreen)
- for a signal (Clutter.Stage::fullscreen)
For these reasons, the :fullscreen should be renamed to :fullscreen-set
and be read-only. Implementations of the Stage should only emit the
StageState event to change from normal to fullscreen, and the Stage
will automatically update the value of the property and emit a notify
signal for it.
Setting the stage size using clutter_actor_set_size() is almost always
wrong: the X11 stage implementation should save the size and queue a
relayout -- like it does when receiving a ConfigureNotify. The same
should happen when setting it to be full screen.
The mapping and unmapping of the X11 stage implementation is
a bit bong. It's asynchronous, for starters, when it really
can avoid it by tracking the state internally.
The ordering of the map/unmap sequence is also broken with
respect to the resizing.
By tracking the state internally into StageX11 we can safely
remove the MapNotify and UnmapNotify X event handling.
In theory, we should use _NET_WM_STATE a lot more, and reuse
the X11 state flags for fullscreening as well.
Instead of passing a boolean value, the ::allocate virtual function
should use a bitmask and flags. This gives us room for expansion
without breaking API/ABI, and allows to encode more information to
the allocation process instead of just changes of absolute origin.
The XVisualInfo for GL is created when a stage is being realized.
When embedding Clutter inside another toolkit we might not want to
realize a stage to extract the XVisualInfo, then set the stage
window using a foreign X Window -- which will cause a re-realization.
Instead, we should abstract as much as possible into the X11 backend.
Unfortunately, the XVisualInfo for GL is requested using GLX API; for
this reason we have to create a ClutterBackendX11 method that we
override inside the ClutterBackendGLX implementation.
This also allows us to move a little bit of complexity from out of
the stage realization, which is currently a very delicate and hard
to debug section.
Setting the stage window using the set_stage_foreign() method will
lead to a re-realization. We need to make sure that the Drawable
currently associated to the GL context is set to None, to avoid a
BadDrawable error or, if we're unlucky, a segfault in the X server.
With the recent change to internal floating point values, ClutterUnit
has become a redundant type, defined to be a float. All integer entry
points are being internally converted to floating point values to be
passed to the GL pipeline with the least amount of conversion.
ClutterUnit is thus exposed as just a "pixel with fractionary bits",
and not -- as users might think -- as generic, resolution and device
independent units. not that it was the case, but a definitive amount
of people was convinced it did provide this "feature", and was flummoxed
about the mere existence of this type.
So, having ClutterUnit exposed in the public API doubles the entry
points and has the following disadvantages:
- we have to maintain twice the amount of entry points in ClutterActor
- we still do an integer-to-float implicit conversion
- we introduce a weird impedance between pixels and "pixels with
fractionary bits"
- language bindings will have to choose what to bind, and resort
to manually overriding the API
+ *except* for language bindings based on GObject-Introspection, as
they cannot do manual overrides, thus will replicate the entire
set of entry points
For these reason, we should coalesces every Actor entry point for
pixels and for ClutterUnit into a single entry point taking a float,
like:
void clutter_actor_set_x (ClutterActor *self,
gfloat x);
void clutter_actor_get_size (ClutterActor *self,
gfloat *width,
gfloat *height);
gfloat clutter_actor_get_height (ClutterActor *self);
etc.
The issues I have identified are:
- we'll have a two cases of compiler warnings:
- printf() format of the return values from %d to %f
- clutter_actor_get_size() taking floats instead of unsigned ints
- we'll have a problem with varargs when passing an integer instead
of a floating point value, except on 64bit platforms where the
size of a float is the same as the size of an int
To be clear: the *intent* of the API should not change -- we still use
pixels everywhere -- but:
- we remove ambiguity in the API with regard to pixels and units
- we remove entry points we get to maintain for the whole 1.0
version of the API
- we make things simpler to bind for both manual language bindings
and automatic (gobject-introspection based) ones
- we have the simplest API possible while still exposing the
capabilities of the underlying GL implementation
Bug 1138 - No trackable "mapped" state
* Add a VISIBLE flag tracking application programmer's
expected showing-state for the actor, allowing us to
always ensure we keep what the app wants while tracking
internal implementation state separately.
* Make MAPPED reflect whether the actor will be painted;
add notification on a ClutterActor::mapped property.
Keep MAPPED state updated as the actor is shown,
ancestors are shown, actor is reparented, etc.
* Require a stage and realized parents to realize; this means
at realization time the correct window system and GL resources
are known. But unparented actors can no longer be realized.
* Allow children to be unrealized even if parent is realized.
Otherwise in effect either all actors or no actors are realized,
i.e. it becomes a stage-global flag.
* Allow clutter_actor_realize() to "fail" if not inside a toplevel
* Rework clutter_actor_unrealize() so internally we have
a flavor that does not mess with visibility flag
* Add _clutter_actor_rerealize() to encapsulate a somewhat
tricky operation we were doing in a couple of places
* Do not realize/unrealize children in ClutterGroup,
ClutterActor already does it
* Do not realize impl by hand in clutter_stage_show(),
since showing impl already does that
* Do not unrealize in various dispose() methods, since
ClutterActor dispose implementation already does it
and chaining up is mandatory
* ClutterTexture uses COGL while unrealizable (before it's
added to a stage). Previously this breakage was affecting
ClutterActor because we had to allow realize outside
a stage. Move the breakage to ClutterTexture, by making
ClutterTexture just use COGL while not realized.
* Unrealize before we set parent to NULL in clutter_actor_unparent().
This means unrealize() implementations can get to the stage.
Because actors need the stage in order to detach from stage.
* Update clutter-actor-invariants.txt to reflect latest changes
* Remove explicit hide/unrealize from ClutterActor::dispose since
unparent already forces those
Instead just assert that unparent() occurred and did the right thing.
* Check whether parent implements unrealize before chaining up
Needed because ClutterGroup no longer has to implement unrealize.
* Perform unrealize in the default handler for the signal.
This allows non-containers that have children to work properly,
and allows containers to override how it's done.
* Add map/unmap virtual methods and set MAPPED flag on self and
children in there. This allows subclasses to hook map/unmap.
These are not signals, because notify::mapped is better for
anything it's legitimate for a non-subclass to do.
Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
Bug 1516 - Does not withdraw toplevels correctly
clutter_stage_x11_hide() needs to use XWithdrawWindow(), not
XUnmapWindow().
As it stands now, if the window is already unmapped (say the WM has
minimized it), then the WM will not know that Clutter has closed the
window and will keep the window managed, showing it in the task list
and so forth.
If the stage is unrealized (such as will be the case if the stage was
created with clutter_stage_new) then it would set the size of the
stage display but it was not setting the fullscreen_on_map flag so it
never got the _NET_WM_STATE_FULLSCREEN property. Now it always sets
the flag regardless of whether the window is created yet.
There was also problems with dual-headed displays because in that case
DisplayWidth/Height will return the size of the combined display but
Metacity (and presumably other WMs) will sensibly try fit the window
to only one of the monitors. However we were setting the size hints so
that the minimum size is that of the combined display. Metacity tries
to honour this by setting the minimum size but then it no longer
positions the window at the top left of the screen.
The patch makes it avoid setting the minimum size when the stage is
fullscreen by checking the fullscreen_on_map flag. This also means we
can remove the static was_resizable flag which would presumably have
caused problems for multi-stage.
Since Clutter changed to using a layout scheme the handling_configure
flag no longer works because the allocate method is not invoked
immediately during the call to set_size from the ConfigureNotify
handler. However it is also no longer neccessary because the resizes
are effectively batched up until a relayout is run so it won't cause
an infinite loop of resize and notify events anyway.
Continuation of the fix in commit 00a3c69868.
Instead of using a separate flag for the resize process, just
delay the setting of the CLUTTER_ACTOR_SYNC_MATRICES flag on the
stage to the point when we receive a ConfigureNotify event from
X11.
This commit will break the stage embedding into other toolkits.
There is a race condition when we resize a stage before showing
it on X11.
The race goes like this:
- clutter_init() creates the default stage and realize it, which
will cause a 640x480 Window to be created
- call set_size(800, 600) on the stage will cause the Window to be
resized to 800x600
- call show() on the stage for the first time will cause COGL
to set up an 800 by 600 GL viewport
- the Window will be mapped, which will cause X to notify the
window manager that the Window should be resized to 800x600
- the window manager will approve the resize
- X resizes the drawable to 800x600
To fix the race, we need to defer COGL from setting up the viewport
until we receive a ConfigureNotify event and the X server has resized
the Drawable.
In order to defer the call to cogl_setup_viewport() we add a new
private flag, CLUTTER_STAGE_IN_RESIZE; the flag is checked whenever
we need to change the viewport size along with the SYNC_MATRICES
private flag. Thus, cogl_setup_viewport() will be called only if
SYNC_MATRICES is set and IN_RESIZE is not set.
Bug #815 - Split up request, allocation, and paint box
* clutter/clutter-actor.[ch]: Rework the size allocation,
request and paint area. Now ::request_coords() is called
::allocate(), and ::query_coords() has been split into
::get_preferred_width() and ::get_preferred_height(). See
the documentation and the layout test on how to implement
a container and layout manager with the new API. (#915,
based on a patch by Havoc Pennington, Lucas Rocha and Johan
Bilien)
* clutter/clutter-clone-texture.c: Port CloneTexture to
the new size negotiation API; it just means forwarding
the requests to the parent texture.
* clutter/clutter-deprecated.h: Add deprecated and replaced
API.
* clutter/clutter-entry.c: Port Entry to the new size
negotiation API.
* clutter/clutter-group.c: Port Group to the new size
negotiation API; the semantics of the Group actor do not
change.
* clutter/clutter-label.c: Port Label to the new size
negotiation API, and vastly simplify the code.
* clutter/clutter-main.[ch]: Add API for executing a
relayout when needed.
* clutter/clutter-private.h: Add new Stage private API.
* clutter/clutter-rectangle.c: Update the get_abs_opacity()
call to get_paint_opacity().
* clutter/clutter-stage.c:
(clutter_stage_get_preferred_width),
(clutter_stage_get_preferred_height),
(clutter_stage_allocate),
(clutter_stage_class_init): Port Stage to the new size
negotiation API.
* clutter/clutter-texture.c: Port Texture to the new size
negotiation API.
* clutter/clutter-types.h: Add ClutterRequestMode enumeration.
* clutter/x11/clutter-stage-x11.c: Port the X11 stage
implementation to the new size negotiation API.
* tests/Makefile.am: Add the layout manager test case.
* tests/test-opacity.c: Update.
* tests/test-project.c: Update.
* tests/test-layout.c: Test case for a layout manager implemented
using the new size negotiation API; the layout manager handles
both transformed and untransformed children.
* clutter/x11/clutter-event-x11.c (event_translate): Remove the
cheap Expose event compression, as it seems to play games when a
composite manager is running. It's also not really needed, as
the redraw queue will avoid redraws too close to each other
anyway.
* clutter/x11/clutter-stage-x11.c:
(clutter_stage_x11_show), (clutter_stage_x11_hide): Do not chain
up just to set the flags. This fixes a critical warning coming
from ClutterActor::hide() default implementation.
Rework the stage wrapper/implementation relation: remove
duplicated code and all the bookkeeping from the backends into
ClutterStage whenever possible, to reduce the amount of work a
backend must do (and possibly get wrong). Thanks to Tommi
Komulainen.
* clutter/clutter-main.c:
(clutter_init_with_args), (clutter_init): Realize the default
stage after creation. The default stage is special, because we
use it in the initialization sequence. This removes the burden
from the backends and reduces the things a backend can get
wrong.
* clutter/clutter-stage.c:
(clutter_stage_show): Make sure to realize the implementation if
it hasn't been realized yet.
(clutter_stage_realize): Set the REALIZED flag and call
clutter_stage_ensure_current() if the implementation was
successfully realized.
(clutter_stage_unrealized): Call clutter_stage_ensure_current()
on unrealize.
* clutter/glx/clutter-backend-glx.c:
(clutter_backend_glx_create_stage): Do not realize the stage anymore
when creating it, and let the normal realization sequence take
place.
(clutter_backend_glx_ensure_context): Trap for X11 errors.
* clutter/glx/clutter-stage-glx.c:
(clutter_stage_glx_realize): Chain up to the X11 implementation
so that we can set up the window state (title, cursor visibility)
when we actually have a X window. Also, do not call
clutter_stage_ensure_current(), and rely on the wrapper to do
it for us. This means we can drop setting the REALIZED flag on
the wrapper.
(clutter_stage_glx_unrealize): Do not call
clutter_stage_ensure_current() ourselves, and rely on the wrapper
to do it for us.
* clutter/x11/clutter-stage-x11.c:
(set_wm_title), (set_cursor_visible): Move the WM title and
cursor visibility code inside their own functions.
(clutter_stage_x11_realize): Set the window title and whether the
cursor is visible or not after realizing the stage.
(clutter_stage_x11_set_cursor_visible),
(clutter_stage_x11_set_title): Call set_wm_title() and
set_cursor_visible().
(clutter_stage_x11_finalize): Free the title string.
* clutter/x11/clutter-stage-x11.h: Save more of the stage state,
so that we can set it even when the stage hasn't been realized
yet.
* clutter/eglnative/clutter-backend-egl.c:
(clutter_backend_egl_create_stage):
* clutter/eglnative/clutter-stage-egl.c:
(clutter_stage_egl_unrealize),
(clutter_stage_egl_realize): Update the eglnative backend.
* clutter/eglx/clutter-backend-egl.c:
(clutter_backend_egl_ensure_context),
(clutter_backend_egl_create_stage):
* clutter/eglx/clutter-stage-egl.c:
(clutter_stage_egl_unrealize),
(clutter_stage_egl_realize): Update the eglx backend.
* clutter/sdl/clutter-backend-sdl.c:
(clutter_backend_sdl_create_stage):
* clutter/sdl/clutter-stage-sdl.c:
(clutter_stage_sdl_realize): Update the sdl backend.
* clutter/fruity/clutter-backend-fruity.c:
(clutter_backend_fruity_create_stage):
* clutter/sdl/clutter-stage-fruity.c:
(clutter_stage_fruity_realize): Update the fruity backend.
* tests/test-multistage.c (on_button_press): Bail out if
clutter_stage_new() returns NULL.
* HACKING.backends: Update backend writing documentation.
* clutter/clutter-backend.c: Add more debug messages
* clutter/clutter-stage.h:
* clutter/clutter-stage.c:
(clutter_stage_is_default): Add a function to check if the
stage is the default one.
* clutter/glx/clutter-backend-glx.c:
* clutter/glx/clutter-stage-glx.c:
* clutter/x11/clutter-stage-x11.c: Keep the stage wrapper
and implementation flags in sync, to ensure that the GL
context is always set.
Bug #864 - Allow instantiating and subclassing of ClutterStage
* clutter/Makefile.am: Add clutter-stage-window.[ch]
* clutter/clutter-stage-manager.c:
(_clutter_stage_manager_remove_stage): Do not warn if removing
a stage we don't manage, as we might be invoked multiple times
during a ClutterState dispose sequence.
* clutter/clutter-actor.c:
* clutter/clutter-backend.[ch]:
* clutter/clutter-main.c:
* clutter/clutter-private.h:
* clutter/clutter-stage.[ch]: Make ClutterStage a proxy actor,
with a private actor implementing the ClutterStageWindow
interface for handling the per-backend realization, painting
and unrealization, plus all the windowing system abstraction.
* clutter/x11/clutter-event-x11.c:
* clutter/x11/clutter-stage-x11.[ch]: Port the X11 backend
to the new backend and stage API and semantics.
* clutter/glx/clutter-backend-glx.c:
* clutter/glx/clutter-stage-glx.c: Port the GLX backend to
the new backend and stage API and semantics.
* clutter/eglx/clutter-backend-egl.[ch]:
* clutter/eglx/clutter-stage-egl.[ch]: Port the EGLX backend
to the new backend and stage API and semantics (untested).
* tests/test-multistage.c (on_button_press): Rename
clutter_stage_create_new() to clutter_stage_new().
Applied patch from bug #810.
* clutter/x11/clutter-event-x11.c (event_translate): Set a flag
when resizing the stage from a ConfigureNotify event.
* clutter/x11/clutter-stage-x11.c
(clutter_stage_x11_request_coords): Don't try to resize the window
again if the flag is set.
(clutter_stage_x11_init): Added initialiser for the flag.
* clutter/x11/clutter-stage-x11.h (struct _ClutterStageX11): Added
the flag.
* clutter/x11/clutter-event-x11.c (event_translate): Ignore
PropertyNotify events if they don't match our window.
* clutter/x11/clutter-stage-x11.c:
(clutter_stage_x11_request_coords): Chain up to the parent's
request coords.
* clutter/x11/clutter-event-x11.c (event_translate): Ignore
ConfigureNotify events if we are painting on a foreign window.
* clutter/x11/clutter-stage-x11.c:
(clutter_stage_x11_request_coords): Reliquish control of the
window size, if we are painting on a foreign window. This fixes
the GtkClutterEmbed widget.
* clutter/clutter-feature.h:
* clutter/clutter-texture.c:
* clutter/clutter-texture.h:
* clutter/cogl/cogl.h:
* clutter/cogl/gl/cogl.c:
* clutter/cogl/gles/cogl.c:
* tests/Makefile.am:
* tests/test.fbo.c:
Add initial support for FBO's in Clutter (OpenGL only so far).
See new clutter_texture_new_from_actor()
Initial implementation, needs work.
* clutter/x11/clutter-stage-x11.c:
(clutter_stage_x11_set_cursor_visible):
Fall back to again not relying on xfixes to hide cursor. *sigh*
* clutter/clutter-deprecated.h:
Add clutter_group_find_child_by_id
