mutter/clutter/clutter-input-device.c
Florian Müllner f6ad53d9e0 input-device: Guard against double free
Dispose() may be called more than once, so calling g_free directly
on the device name is unsafe. Instead, use g_clear_pointer() to
make sure we don't attempt to free the memory again.

https://bugzilla.gnome.org/show_bug.cgi?id=719563
2013-12-02 00:29:47 +01:00

1905 lines
52 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright © 2009, 2010, 2011 Intel Corp.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
* Author: Emmanuele Bassi <ebassi@linux.intel.com>
*/
/**
* SECTION:clutter-input-device
* @short_description: An input device managed by Clutter
*
* #ClutterInputDevice represents an input device known to Clutter.
*
* The #ClutterInputDevice class holds the state of the device, but
* its contents are usually defined by the Clutter backend in use.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "clutter-input-device.h"
#include "clutter-actor-private.h"
#include "clutter-debug.h"
#include "clutter-device-manager-private.h"
#include "clutter-enum-types.h"
#include "clutter-event-private.h"
#include "clutter-marshal.h"
#include "clutter-private.h"
#include "clutter-stage-private.h"
enum
{
PROP_0,
PROP_BACKEND,
PROP_ID,
PROP_NAME,
PROP_DEVICE_TYPE,
PROP_DEVICE_MANAGER,
PROP_DEVICE_MODE,
PROP_HAS_CURSOR,
PROP_ENABLED,
PROP_N_AXES,
PROP_LAST
};
static void _clutter_input_device_free_touch_info (gpointer data);
static GParamSpec *obj_props[PROP_LAST] = { NULL, };
G_DEFINE_TYPE (ClutterInputDevice, clutter_input_device, G_TYPE_OBJECT);
static void
clutter_input_device_dispose (GObject *gobject)
{
ClutterInputDevice *device = CLUTTER_INPUT_DEVICE (gobject);
g_clear_pointer (&device->device_name, g_free);
if (device->associated != NULL)
{
if (device->device_mode == CLUTTER_INPUT_MODE_SLAVE)
_clutter_input_device_remove_slave (device->associated, device);
_clutter_input_device_set_associated_device (device->associated, NULL);
g_object_unref (device->associated);
device->associated = NULL;
}
if (device->axes != NULL)
{
g_array_free (device->axes, TRUE);
device->axes = NULL;
}
if (device->keys != NULL)
{
g_array_free (device->keys, TRUE);
device->keys = NULL;
}
if (device->touch_sequences_info)
{
g_hash_table_unref (device->touch_sequences_info);
device->touch_sequences_info = NULL;
}
if (device->inv_touch_sequence_actors)
{
GHashTableIter iter;
gpointer key, value;
g_hash_table_iter_init (&iter, device->inv_touch_sequence_actors);
while (g_hash_table_iter_next (&iter, &key, &value))
g_list_free (value);
g_hash_table_unref (device->inv_touch_sequence_actors);
device->inv_touch_sequence_actors = NULL;
}
G_OBJECT_CLASS (clutter_input_device_parent_class)->dispose (gobject);
}
static void
clutter_input_device_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
ClutterInputDevice *self = CLUTTER_INPUT_DEVICE (gobject);
switch (prop_id)
{
case PROP_ID:
self->id = g_value_get_int (value);
break;
case PROP_DEVICE_TYPE:
self->device_type = g_value_get_enum (value);
break;
case PROP_DEVICE_MANAGER:
self->device_manager = g_value_get_object (value);
break;
case PROP_DEVICE_MODE:
self->device_mode = g_value_get_enum (value);
break;
case PROP_BACKEND:
self->backend = g_value_get_object (value);
break;
case PROP_NAME:
self->device_name = g_value_dup_string (value);
break;
case PROP_HAS_CURSOR:
self->has_cursor = g_value_get_boolean (value);
break;
case PROP_ENABLED:
clutter_input_device_set_enabled (self, g_value_get_boolean (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_input_device_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterInputDevice *self = CLUTTER_INPUT_DEVICE (gobject);
switch (prop_id)
{
case PROP_ID:
g_value_set_int (value, self->id);
break;
case PROP_DEVICE_TYPE:
g_value_set_enum (value, self->device_type);
break;
case PROP_DEVICE_MANAGER:
g_value_set_object (value, self->device_manager);
break;
case PROP_DEVICE_MODE:
g_value_set_enum (value, self->device_mode);
break;
case PROP_BACKEND:
g_value_set_object (value, self->backend);
break;
case PROP_NAME:
g_value_set_string (value, self->device_name);
break;
case PROP_HAS_CURSOR:
g_value_set_boolean (value, self->has_cursor);
break;
case PROP_N_AXES:
g_value_set_uint (value, clutter_input_device_get_n_axes (self));
break;
case PROP_ENABLED:
g_value_set_boolean (value, self->is_enabled);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_input_device_class_init (ClutterInputDeviceClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
/**
* ClutterInputDevice:id:
*
* The unique identifier of the device
*
*
*/
obj_props[PROP_ID] =
g_param_spec_int ("id",
P_("Id"),
P_("Unique identifier of the device"),
-1, G_MAXINT,
0,
CLUTTER_PARAM_READWRITE |
G_PARAM_CONSTRUCT_ONLY);
/**
* ClutterInputDevice:name:
*
* The name of the device
*
*
*/
obj_props[PROP_NAME] =
g_param_spec_string ("name",
P_("Name"),
P_("The name of the device"),
NULL,
CLUTTER_PARAM_READWRITE |
G_PARAM_CONSTRUCT_ONLY);
/**
* ClutterInputDevice:device-type:
*
* The type of the device
*
*
*/
obj_props[PROP_DEVICE_TYPE] =
g_param_spec_enum ("device-type",
P_("Device Type"),
P_("The type of the device"),
CLUTTER_TYPE_INPUT_DEVICE_TYPE,
CLUTTER_POINTER_DEVICE,
CLUTTER_PARAM_READWRITE |
G_PARAM_CONSTRUCT_ONLY);
/**
* ClutterInputDevice:device-manager:
*
* The #ClutterDeviceManager instance which owns the device
*
*
*/
obj_props[PROP_DEVICE_MANAGER] =
g_param_spec_object ("device-manager",
P_("Device Manager"),
P_("The device manager instance"),
CLUTTER_TYPE_DEVICE_MANAGER,
CLUTTER_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY);
/**
* ClutterInputDevice:mode:
*
* The mode of the device.
*
*
*/
obj_props[PROP_DEVICE_MODE] =
g_param_spec_enum ("device-mode",
P_("Device Mode"),
P_("The mode of the device"),
CLUTTER_TYPE_INPUT_MODE,
CLUTTER_INPUT_MODE_FLOATING,
CLUTTER_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY);
/**
* ClutterInputDevice:has-cursor:
*
* Whether the device has an on screen cursor following its movement.
*
*
*/
obj_props[PROP_HAS_CURSOR] =
g_param_spec_boolean ("has-cursor",
P_("Has Cursor"),
P_("Whether the device has a cursor"),
FALSE,
CLUTTER_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY);
/**
* ClutterInputDevice:enabled:
*
* Whether the device is enabled.
*
* A device with the #ClutterInputDevice:device-mode property set
* to %CLUTTER_INPUT_MODE_MASTER cannot be disabled.
*
* A device must be enabled in order to receive events from it.
*
*
*/
obj_props[PROP_ENABLED] =
g_param_spec_boolean ("enabled",
P_("Enabled"),
P_("Whether the device is enabled"),
FALSE,
CLUTTER_PARAM_READWRITE);
/**
* ClutterInputDevice:n-axes:
*
* The number of axes of the device.
*
*
*/
obj_props[PROP_N_AXES] =
g_param_spec_uint ("n-axes",
P_("Number of Axes"),
P_("The number of axes on the device"),
0, G_MAXUINT,
0,
CLUTTER_PARAM_READABLE);
/**
* ClutterInputDevice:backend:
*
* The #ClutterBackend that created the device.
*
*
*/
obj_props[PROP_BACKEND] =
g_param_spec_object ("backend",
P_("Backend"),
P_("The backend instance"),
CLUTTER_TYPE_BACKEND,
CLUTTER_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY);
gobject_class->dispose = clutter_input_device_dispose;
gobject_class->set_property = clutter_input_device_set_property;
gobject_class->get_property = clutter_input_device_get_property;
g_object_class_install_properties (gobject_class, PROP_LAST, obj_props);
}
static void
clutter_input_device_init (ClutterInputDevice *self)
{
self->id = -1;
self->device_type = CLUTTER_POINTER_DEVICE;
self->click_count = 0;
self->current_time = self->previous_time = CLUTTER_CURRENT_TIME;
self->current_x = self->previous_x = -1;
self->current_y = self->previous_y = -1;
self->current_button_number = self->previous_button_number = -1;
self->current_state = self->previous_state = 0;
self->touch_sequences_info =
g_hash_table_new_full (NULL, NULL,
NULL, _clutter_input_device_free_touch_info);
self->inv_touch_sequence_actors = g_hash_table_new (NULL, NULL);
}
static ClutterTouchInfo *
_clutter_input_device_ensure_touch_info (ClutterInputDevice *device,
ClutterEventSequence *sequence,
ClutterStage *stage)
{
ClutterTouchInfo *info;
info = g_hash_table_lookup (device->touch_sequences_info, sequence);
if (info == NULL)
{
info = g_slice_new0 (ClutterTouchInfo);
info->sequence = sequence;
g_hash_table_insert (device->touch_sequences_info, sequence, info);
if (g_hash_table_size (device->touch_sequences_info) == 1)
_clutter_input_device_set_stage (device, stage);
}
return info;
}
/*< private >
* clutter_input_device_set_coords:
* @device: a #ClutterInputDevice
* @sequence: a #ClutterEventSequence or NULL
* @x: X coordinate of the device
* @y: Y coordinate of the device
*
* Stores the last known coordinates of the device
*/
void
_clutter_input_device_set_coords (ClutterInputDevice *device,
ClutterEventSequence *sequence,
gint x,
gint y,
ClutterStage *stage)
{
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
if (sequence == NULL)
{
if (device->current_x != x)
device->current_x = x;
if (device->current_y != y)
device->current_y = y;
}
else
{
ClutterTouchInfo *info;
info = _clutter_input_device_ensure_touch_info (device, sequence, stage);
info->current_x = x;
info->current_y = y;
}
}
/*< private >
* clutter_input_device_set_state:
* @device: a #ClutterInputDevice
* @state: a bitmask of modifiers
*
* Stores the last known modifiers state of the device
*/
void
_clutter_input_device_set_state (ClutterInputDevice *device,
ClutterModifierType state)
{
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
device->current_state = state;
}
/*< private >
* clutter_input_device_set_time:
* @device: a #ClutterInputDevice
* @time_: the time
*
* Stores the last known event time of the device
*/
void
_clutter_input_device_set_time (ClutterInputDevice *device,
guint32 time_)
{
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
if (device->current_time != time_)
device->current_time = time_;
}
/*< private >
* clutter_input_device_set_stage:
* @device: a #ClutterInputDevice
* @stage: a #ClutterStage or %NULL
*
* Stores the stage under the device
*/
void
_clutter_input_device_set_stage (ClutterInputDevice *device,
ClutterStage *stage)
{
if (device->stage == stage)
return;
device->stage = stage;
/* we leave the ->cursor_actor in place in order to check
* if we left the stage without crossing it again; this way
* we can emit a leave event on the cursor actor right before
* we emit the leave event on the stage.
*/
}
/*< private >
* clutter_input_device_get_stage:
* @device: a #ClutterInputDevice
*
* Retrieves the stage currently associated with @device.
*
* Return value: The stage currently associated with @device.
*/
ClutterStage *
_clutter_input_device_get_stage (ClutterInputDevice *device)
{
return device->stage;
}
static void
_clutter_input_device_free_touch_info (gpointer data)
{
g_slice_free (ClutterTouchInfo, data);
}
static ClutterActor *
_clutter_input_device_get_actor (ClutterInputDevice *device,
ClutterEventSequence *sequence)
{
ClutterTouchInfo *info;
if (sequence == NULL)
return device->cursor_actor;
info = g_hash_table_lookup (device->touch_sequences_info, sequence);
return info->actor;
}
static void on_cursor_actor_destroy (ClutterActor *actor,
ClutterInputDevice *device);
static void
_clutter_input_device_associate_actor (ClutterInputDevice *device,
ClutterEventSequence *sequence,
ClutterActor *actor)
{
if (sequence == NULL)
device->cursor_actor = actor;
else
{
GList *sequences =
g_hash_table_lookup (device->inv_touch_sequence_actors, actor);
ClutterTouchInfo *info;
ClutterStage *stage = CLUTTER_STAGE (clutter_actor_get_stage (actor));
info = _clutter_input_device_ensure_touch_info (device, sequence, stage);
info->actor = actor;
g_hash_table_insert (device->inv_touch_sequence_actors,
actor, g_list_prepend (sequences, sequence));
}
g_signal_connect (actor,
"destroy", G_CALLBACK (on_cursor_actor_destroy),
device);
_clutter_actor_set_has_pointer (actor, TRUE);
}
static void
_clutter_input_device_unassociate_actor (ClutterInputDevice *device,
ClutterActor *actor,
gboolean destroyed)
{
if (device->cursor_actor == actor)
device->cursor_actor = NULL;
else
{
GList *l, *sequences =
g_hash_table_lookup (device->inv_touch_sequence_actors,
actor);
for (l = sequences; l != NULL; l = l->next)
{
ClutterTouchInfo *info =
g_hash_table_lookup (device->touch_sequences_info, l->data);
if (info)
info->actor = NULL;
}
g_list_free (sequences);
g_hash_table_remove (device->inv_touch_sequence_actors, actor);
}
if (destroyed == FALSE)
{
g_signal_handlers_disconnect_by_func (actor,
G_CALLBACK (on_cursor_actor_destroy),
device);
_clutter_actor_set_has_pointer (actor, FALSE);
}
}
static void
on_cursor_actor_destroy (ClutterActor *actor,
ClutterInputDevice *device)
{
_clutter_input_device_unassociate_actor (device, actor, TRUE);
}
/*< private >
* clutter_input_device_set_actor:
* @device: a #ClutterInputDevice
* @actor: a #ClutterActor
* @emit_crossing: %TRUE to emit crossing events
*
* Sets the actor under the pointer coordinates of @device
*
* This function is called by _clutter_input_device_update()
* and it will:
*
* - queue a %CLUTTER_LEAVE event on the previous pointer actor
* of @device, if any
* - set to %FALSE the :has-pointer property of the previous
* pointer actor of @device, if any
* - queue a %CLUTTER_ENTER event on the new pointer actor
* - set to %TRUE the :has-pointer property of the new pointer
* actor
*/
void
_clutter_input_device_set_actor (ClutterInputDevice *device,
ClutterEventSequence *sequence,
ClutterActor *actor,
gboolean emit_crossing)
{
ClutterActor *old_actor = _clutter_input_device_get_actor (device, sequence);
if (old_actor == actor)
return;
if (old_actor != NULL)
{
ClutterActor *tmp_old_actor;
if (emit_crossing)
{
ClutterEvent *event;
event = clutter_event_new (CLUTTER_LEAVE);
event->crossing.time = device->current_time;
event->crossing.flags = 0;
event->crossing.stage = device->stage;
event->crossing.source = old_actor;
event->crossing.x = device->current_x;
event->crossing.y = device->current_y;
event->crossing.related = actor;
clutter_event_set_device (event, device);
/* we need to make sure that this event is processed
* before any other event we might have queued up until
* now, so we go on, and synthesize the event emission
* ourselves
*/
_clutter_process_event (event);
clutter_event_free (event);
}
/* processing the event might have destroyed the actor */
tmp_old_actor = _clutter_input_device_get_actor (device, sequence);
_clutter_input_device_unassociate_actor (device,
old_actor,
tmp_old_actor == NULL);
old_actor = tmp_old_actor;
}
if (actor != NULL)
{
_clutter_input_device_associate_actor (device, sequence, actor);
if (emit_crossing)
{
ClutterEvent *event;
event = clutter_event_new (CLUTTER_ENTER);
event->crossing.time = device->current_time;
event->crossing.flags = 0;
event->crossing.stage = device->stage;
event->crossing.x = device->current_x;
event->crossing.y = device->current_y;
event->crossing.source = actor;
event->crossing.related = old_actor;
clutter_event_set_device (event, device);
/* see above */
_clutter_process_event (event);
clutter_event_free (event);
}
}
}
/**
* clutter_input_device_get_device_type:
* @device: a #ClutterInputDevice
*
* Retrieves the type of @device
*
* Return value: the type of the device
*
*
*/
ClutterInputDeviceType
clutter_input_device_get_device_type (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device),
CLUTTER_POINTER_DEVICE);
return device->device_type;
}
/**
* clutter_input_device_get_device_id:
* @device: a #ClutterInputDevice
*
* Retrieves the unique identifier of @device
*
* Return value: the identifier of the device
*
*
*/
gint
clutter_input_device_get_device_id (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), -1);
return device->id;
}
/**
* clutter_input_device_set_enabled:
* @device: a #ClutterInputDevice
* @enabled: %TRUE to enable the @device
*
* Enables or disables a #ClutterInputDevice.
*
* Only devices with a #ClutterInputDevice:device-mode property set
* to %CLUTTER_INPUT_MODE_SLAVE or %CLUTTER_INPUT_MODE_FLOATING can
* be disabled.
*
*
*/
void
clutter_input_device_set_enabled (ClutterInputDevice *device,
gboolean enabled)
{
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
enabled = !!enabled;
if (!enabled && device->device_mode == CLUTTER_INPUT_MODE_MASTER)
return;
if (device->is_enabled == enabled)
return;
device->is_enabled = enabled;
g_object_notify_by_pspec (G_OBJECT (device), obj_props[PROP_ENABLED]);
}
/**
* clutter_input_device_get_enabled:
* @device: a #ClutterInputDevice
*
* Retrieves whether @device is enabled.
*
* Return value: %TRUE if the device is enabled
*
*
*/
gboolean
clutter_input_device_get_enabled (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
return device->is_enabled;
}
/**
* clutter_input_device_get_coords:
* @device: a #ClutterInputDevice
* @sequence: (allow-none): a #ClutterEventSequence, or %NULL if
* the device is not touch-based
* @point: (out caller-allocates): return location for the pointer
* or touch point
*
* Retrieves the latest coordinates of a pointer or touch point of
* @device.
*
* Return value: %FALSE if the device's sequence hasn't been found,
* and %TRUE otherwise.
*
*
*/
gboolean
clutter_input_device_get_coords (ClutterInputDevice *device,
ClutterEventSequence *sequence,
ClutterPoint *point)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
g_return_val_if_fail (point != NULL, FALSE);
if (sequence == NULL)
{
point->x = device->current_x;
point->y = device->current_y;
}
else
{
ClutterTouchInfo *info =
g_hash_table_lookup (device->touch_sequences_info, sequence);
if (info == NULL)
return FALSE;
point->x = info->current_x;
point->y = info->current_y;
}
return TRUE;
}
/*
* _clutter_input_device_update:
* @device: a #ClutterInputDevice
*
* Updates the input @device by determining the #ClutterActor underneath the
* pointer's cursor
*
* This function calls _clutter_input_device_set_actor() if needed.
*
* This function only works for #ClutterInputDevice of type
* %CLUTTER_POINTER_DEVICE.
*
*
*/
ClutterActor *
_clutter_input_device_update (ClutterInputDevice *device,
ClutterEventSequence *sequence,
gboolean emit_crossing)
{
ClutterStage *stage;
ClutterActor *new_cursor_actor;
ClutterActor *old_cursor_actor;
ClutterPoint point = { -1, -1 };
if (device->device_type == CLUTTER_KEYBOARD_DEVICE)
return NULL;
stage = device->stage;
if (G_UNLIKELY (stage == NULL))
{
CLUTTER_NOTE (EVENT, "No stage defined for device %d '%s'",
clutter_input_device_get_device_id (device),
clutter_input_device_get_device_name (device));
return NULL;
}
clutter_input_device_get_coords (device, sequence, &point);
old_cursor_actor = _clutter_input_device_get_actor (device, sequence);
new_cursor_actor =
_clutter_stage_do_pick (stage, point.x, point.y, CLUTTER_PICK_REACTIVE);
/* if the pick could not find an actor then we do not update the
* input device, to avoid ghost enter/leave events; the pick should
* never fail, except for bugs in the glReadPixels() implementation
* in which case this is the safest course of action anyway
*/
if (new_cursor_actor == NULL)
return NULL;
CLUTTER_NOTE (EVENT,
"Actor under cursor (device %d, at %.2f, %.2f): %s",
clutter_input_device_get_device_id (device),
point.x,
point.y,
_clutter_actor_get_debug_name (new_cursor_actor));
/* short-circuit here */
if (new_cursor_actor == old_cursor_actor)
return old_cursor_actor;
_clutter_input_device_set_actor (device, sequence,
new_cursor_actor,
emit_crossing);
return new_cursor_actor;
}
/**
* clutter_input_device_get_pointer_actor:
* @device: a #ClutterInputDevice of type %CLUTTER_POINTER_DEVICE
*
* Retrieves the #ClutterActor underneath the pointer of @device
*
* Return value: (transfer none): a pointer to the #ClutterActor or %NULL
*
*
*/
ClutterActor *
clutter_input_device_get_pointer_actor (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), NULL);
g_return_val_if_fail (device->device_type == CLUTTER_POINTER_DEVICE, NULL);
return device->cursor_actor;
}
/**
* clutter_input_device_get_pointer_stage:
* @device: a #ClutterInputDevice of type %CLUTTER_POINTER_DEVICE
*
* Retrieves the #ClutterStage underneath the pointer of @device
*
* Return value: (transfer none): a pointer to the #ClutterStage or %NULL
*
*
*/
ClutterStage *
clutter_input_device_get_pointer_stage (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), NULL);
g_return_val_if_fail (device->device_type == CLUTTER_POINTER_DEVICE, NULL);
return device->stage;
}
/**
* clutter_input_device_get_device_name:
* @device: a #ClutterInputDevice
*
* Retrieves the name of the @device
*
* Return value: the name of the device, or %NULL. The returned string
* is owned by the #ClutterInputDevice and should never be modified
* or freed
*
*
*/
const gchar *
clutter_input_device_get_device_name (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), NULL);
return device->device_name;
}
/**
* clutter_input_device_get_has_cursor:
* @device: a #ClutterInputDevice
*
* Retrieves whether @device has a pointer that follows the
* device motion.
*
* Return value: %TRUE if the device has a cursor
*
*
*/
gboolean
clutter_input_device_get_has_cursor (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
return device->has_cursor;
}
/**
* clutter_input_device_get_device_mode:
* @device: a #ClutterInputDevice
*
* Retrieves the #ClutterInputMode of @device.
*
* Return value: the device mode
*
*
*/
ClutterInputMode
clutter_input_device_get_device_mode (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device),
CLUTTER_INPUT_MODE_FLOATING);
return device->device_mode;
}
/**
* clutter_input_device_update_from_event:
* @device: a #ClutterInputDevice
* @event: a #ClutterEvent
* @update_stage: whether to update the #ClutterStage of the @device
* using the stage of the event
*
* Forcibly updates the state of the @device using a #ClutterEvent
*
* This function should never be used by applications: it is meant
* for integration with embedding toolkits, like clutter-gtk
*
* Embedding toolkits that disable the event collection inside Clutter
* need to use this function to update the state of input devices depending
* on a #ClutterEvent that they are going to submit to the event handling code
* in Clutter though clutter_do_event(). Since the input devices hold the state
* that is going to be used to fill in fields like the #ClutterButtonEvent
* click count, or to emit synthesized events like %CLUTTER_ENTER and
* %CLUTTER_LEAVE, it is necessary for embedding toolkits to also be
* responsible of updating the input device state.
*
* For instance, this might be the code to translate an embedding toolkit
* native motion notification into a Clutter #ClutterMotionEvent and ask
* Clutter to process it:
*
* |[
* ClutterEvent c_event;
*
* translate_native_event_to_clutter (native_event, &amp;c_event);
*
* clutter_do_event (&amp;c_event);
* ]|
*
* Before letting clutter_do_event() process the event, it is necessary to call
* clutter_input_device_update_from_event():
*
* |[
* ClutterEvent c_event;
* ClutterDeviceManager *manager;
* ClutterInputDevice *device;
*
* translate_native_event_to_clutter (native_event, &amp;c_event);
*
* /&ast; get the device manager &ast;/
* manager = clutter_device_manager_get_default ();
*
* /&ast; use the default Core Pointer that Clutter
* &ast; backends register by default
* &ast;/
* device = clutter_device_manager_get_core_device (manager, %CLUTTER_POINTER_DEVICE);
*
* /&ast; update the state of the input device &ast;/
* clutter_input_device_update_from_event (device, &amp;c_event, FALSE);
*
* clutter_do_event (&amp;c_event);
* ]|
*
* The @update_stage boolean argument should be used when the input device
* enters and leaves a #ClutterStage; it will use the #ClutterStage field
* of the passed @event to update the stage associated to the input device.
*
*
*/
void
clutter_input_device_update_from_event (ClutterInputDevice *device,
ClutterEvent *event,
gboolean update_stage)
{
ClutterModifierType event_state;
ClutterEventSequence *sequence;
ClutterStage *event_stage;
gfloat event_x, event_y;
guint32 event_time;
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
g_return_if_fail (event != NULL);
event_state = clutter_event_get_state (event);
event_time = clutter_event_get_time (event);
event_stage = clutter_event_get_stage (event);
sequence = clutter_event_get_event_sequence (event);
clutter_event_get_coords (event, &event_x, &event_y);
_clutter_input_device_set_coords (device, sequence, event_x, event_y, event_stage);
_clutter_input_device_set_state (device, event_state);
_clutter_input_device_set_time (device, event_time);
if (update_stage)
_clutter_input_device_set_stage (device, event_stage);
}
/*< private >
* clutter_input_device_reset_axes:
* @device: a #ClutterInputDevice
*
* Resets the axes on @device
*/
void
_clutter_input_device_reset_axes (ClutterInputDevice *device)
{
if (device->axes != NULL)
{
g_array_free (device->axes, TRUE);
device->axes = NULL;
g_object_notify_by_pspec (G_OBJECT (device), obj_props[PROP_N_AXES]);
}
}
/*< private >
* clutter_input_device_add_axis:
* @device: a #ClutterInputDevice
* @axis: the axis type
* @minimum: the minimum axis value
* @maximum: the maximum axis value
* @resolution: the axis resolution
*
* Adds an axis of type @axis on @device.
*/
guint
_clutter_input_device_add_axis (ClutterInputDevice *device,
ClutterInputAxis axis,
gdouble minimum,
gdouble maximum,
gdouble resolution)
{
ClutterAxisInfo info;
guint pos;
if (device->axes == NULL)
device->axes = g_array_new (FALSE, TRUE, sizeof (ClutterAxisInfo));
info.axis = axis;
info.min_value = minimum;
info.max_value = maximum;
info.resolution = resolution;
switch (axis)
{
case CLUTTER_INPUT_AXIS_X:
case CLUTTER_INPUT_AXIS_Y:
info.min_axis = 0;
info.max_axis = 0;
break;
case CLUTTER_INPUT_AXIS_XTILT:
case CLUTTER_INPUT_AXIS_YTILT:
info.min_axis = -1;
info.max_axis = 1;
break;
default:
info.min_axis = 0;
info.max_axis = 1;
break;
}
device->axes = g_array_append_val (device->axes, info);
pos = device->axes->len - 1;
g_object_notify_by_pspec (G_OBJECT (device), obj_props[PROP_N_AXES]);
return pos;
}
/*< private >
* clutter_input_translate_axis:
* @device: a #ClutterInputDevice
* @index_: the index of the axis
* @gint: the absolute value of the axis
* @axis_value: (out): the translated value of the axis
*
* Performs a conversion from the absolute value of the axis
* to a relative value.
*
* The axis at @index_ must not be %CLUTTER_INPUT_AXIS_X or
* %CLUTTER_INPUT_AXIS_Y.
*
* Return value: %TRUE if the conversion was successful
*/
gboolean
_clutter_input_device_translate_axis (ClutterInputDevice *device,
guint index_,
gdouble value,
gdouble *axis_value)
{
ClutterAxisInfo *info;
gdouble width;
gdouble real_value;
if (device->axes == NULL || index_ >= device->axes->len)
return FALSE;
info = &g_array_index (device->axes, ClutterAxisInfo, index_);
if (info->axis == CLUTTER_INPUT_AXIS_X ||
info->axis == CLUTTER_INPUT_AXIS_Y)
return FALSE;
width = info->max_value - info->min_value;
real_value = (info->max_axis * (value - info->min_value)
+ info->min_axis * (info->max_value - value))
/ width;
if (axis_value)
*axis_value = real_value;
return TRUE;
}
/**
* clutter_input_device_get_axis:
* @device: a #ClutterInputDevice
* @index_: the index of the axis
*
* Retrieves the type of axis on @device at the given index.
*
* Return value: the axis type
*
*
*/
ClutterInputAxis
clutter_input_device_get_axis (ClutterInputDevice *device,
guint index_)
{
ClutterAxisInfo *info;
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device),
CLUTTER_INPUT_AXIS_IGNORE);
if (device->axes == NULL)
return CLUTTER_INPUT_AXIS_IGNORE;
if (index_ >= device->axes->len)
return CLUTTER_INPUT_AXIS_IGNORE;
info = &g_array_index (device->axes, ClutterAxisInfo, index_);
return info->axis;
}
/**
* clutter_input_device_get_axis_value:
* @device: a #ClutterInputDevice
* @axes: (array): an array of axes values, typically
* coming from clutter_event_get_axes()
* @axis: the axis to extract
* @value: (out): return location for the axis value
*
* Extracts the value of the given @axis of a #ClutterInputDevice from
* an array of axis values.
*
* An example of typical usage for this function is:
*
* |[
* ClutterInputDevice *device = clutter_event_get_device (event);
* gdouble *axes = clutter_event_get_axes (event, NULL);
* gdouble pressure_value = 0;
*
* clutter_input_device_get_axis_value (device, axes,
* CLUTTER_INPUT_AXIS_PRESSURE,
* &amp;pressure_value);
* ]|
*
* Return value: %TRUE if the value was set, and %FALSE otherwise
*
*
*/
gboolean
clutter_input_device_get_axis_value (ClutterInputDevice *device,
gdouble *axes,
ClutterInputAxis axis,
gdouble *value)
{
gint i;
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
g_return_val_if_fail (device->axes != NULL, FALSE);
for (i = 0; i < device->axes->len; i++)
{
ClutterAxisInfo *info;
info = &g_array_index (device->axes, ClutterAxisInfo, i);
if (info->axis == axis)
{
if (value)
*value = axes[i];
return TRUE;
}
}
return FALSE;
}
/**
* clutter_input_device_get_n_axes:
* @device: a #ClutterInputDevice
*
* Retrieves the number of axes available on @device.
*
* Return value: the number of axes on the device
*
*
*/
guint
clutter_input_device_get_n_axes (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), 0);
if (device->axes != NULL)
return device->axes->len;
return 0;
}
/*< private >
* clutter_input_device_set_n_keys:
* @device: a #ClutterInputDevice
* @n_keys: the number of keys of the device
*
* Initializes the keys of @device.
*
* Call clutter_input_device_set_key() on each key to set the keyval
* and modifiers.
*/
void
_clutter_input_device_set_n_keys (ClutterInputDevice *device,
guint n_keys)
{
if (device->keys != NULL)
g_array_free (device->keys, TRUE);
device->n_keys = n_keys;
device->keys = g_array_sized_new (FALSE, TRUE,
sizeof (ClutterKeyInfo),
n_keys);
}
/**
* clutter_input_device_get_n_keys:
* @device: a #ClutterInputDevice
*
* Retrieves the number of keys registered for @device.
*
* Return value: the number of registered keys
*
*
*/
guint
clutter_input_device_get_n_keys (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), 0);
return device->n_keys;
}
/**
* clutter_input_device_set_key:
* @device: a #ClutterInputDevice
* @index_: the index of the key
* @keyval: the keyval
* @modifiers: a bitmask of modifiers
*
* Sets the keyval and modifiers at the given @index_ for @device.
*
* Clutter will use the keyval and modifiers set when filling out
* an event coming from the same input device.
*
*
*/
void
clutter_input_device_set_key (ClutterInputDevice *device,
guint index_,
guint keyval,
ClutterModifierType modifiers)
{
ClutterKeyInfo *key_info;
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
g_return_if_fail (index_ < device->n_keys);
key_info = &g_array_index (device->keys, ClutterKeyInfo, index_);
key_info->keyval = keyval;
key_info->modifiers = modifiers;
}
/**
* clutter_input_device_get_key:
* @device: a #ClutterInputDevice
* @index_: the index of the key
* @keyval: (out): return location for the keyval at @index_
* @modifiers: (out): return location for the modifiers at @index_
*
* Retrieves the key set using clutter_input_device_set_key()
*
* Return value: %TRUE if a key was set at the given index
*
*
*/
gboolean
clutter_input_device_get_key (ClutterInputDevice *device,
guint index_,
guint *keyval,
ClutterModifierType *modifiers)
{
ClutterKeyInfo *key_info;
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
if (device->keys == NULL)
return FALSE;
if (index_ > device->keys->len)
return FALSE;
key_info = &g_array_index (device->keys, ClutterKeyInfo, index_);
if (!key_info->keyval && !key_info->modifiers)
return FALSE;
if (keyval)
*keyval = key_info->keyval;
if (modifiers)
*modifiers = key_info->modifiers;
return TRUE;
}
/*< private >
* clutter_input_device_add_slave:
* @master: a #ClutterInputDevice
* @slave: a #ClutterInputDevice
*
* Adds @slave to the list of slave devices of @master
*
* This function does not increase the reference count of either @master
* or @slave.
*/
void
_clutter_input_device_add_slave (ClutterInputDevice *master,
ClutterInputDevice *slave)
{
if (g_list_find (master->slaves, slave) == NULL)
master->slaves = g_list_prepend (master->slaves, slave);
}
/*< private >
* clutter_input_device_remove_slave:
* @master: a #ClutterInputDevice
* @slave: a #ClutterInputDevice
*
* Removes @slave from the list of slave devices of @master.
*
* This function does not decrease the reference count of either @master
* or @slave.
*/
void
_clutter_input_device_remove_slave (ClutterInputDevice *master,
ClutterInputDevice *slave)
{
if (g_list_find (master->slaves, slave) != NULL)
master->slaves = g_list_remove (master->slaves, slave);
}
/*< private >
* clutter_input_device_add_sequence:
* @device: a #ClutterInputDevice
* @sequence: a #ClutterEventSequence
*
* Start tracking informations related to a touch point (position,
* actor underneath the touch point).
*/
void
_clutter_input_device_add_event_sequence (ClutterInputDevice *device,
ClutterEvent *event)
{
ClutterEventSequence *sequence = clutter_event_get_event_sequence (event);
ClutterStage *stage;
if (sequence == NULL)
return;
stage = clutter_event_get_stage (event);
if (stage == NULL)
return;
_clutter_input_device_ensure_touch_info (device, sequence, stage);
}
/*< private >
* clutter_input_device_remove_sequence:
* @device: a #ClutterInputDevice
* @sequence: a #ClutterEventSequence
*
* Stop tracking informations related to a touch point.
*/
void
_clutter_input_device_remove_event_sequence (ClutterInputDevice *device,
ClutterEvent *event)
{
ClutterEventSequence *sequence = clutter_event_get_event_sequence (event);
ClutterTouchInfo *info =
g_hash_table_lookup (device->touch_sequences_info, sequence);
if (info == NULL)
return;
if (info->actor != NULL)
{
GList *sequences =
g_hash_table_lookup (device->inv_touch_sequence_actors, info->actor);
sequences = g_list_remove (sequences, sequence);
g_hash_table_replace (device->inv_touch_sequence_actors,
info->actor, sequences);
}
g_hash_table_remove (device->touch_sequences_info, sequence);
if (g_hash_table_size (device->touch_sequences_info) == 0)
_clutter_input_device_set_stage (device, NULL);
}
/**
* clutter_input_device_get_slave_devices:
* @device: a #ClutterInputDevice
*
* Retrieves the slave devices attached to @device.
*
* Return value: (transfer container) (element-type Clutter.InputDevice): a
* list of #ClutterInputDevice, or %NULL. The contents of the list are
* owned by the device. Use g_list_free() when done
*
*
*/
GList *
clutter_input_device_get_slave_devices (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), NULL);
return g_list_copy (device->slaves);
}
/*< internal >
* clutter_input_device_set_associated_device:
* @device: a #ClutterInputDevice
* @associated: (allow-none): a #ClutterInputDevice, or %NULL
*
* Sets the associated device for @device.
*
* This function keeps a reference on the associated device.
*/
void
_clutter_input_device_set_associated_device (ClutterInputDevice *device,
ClutterInputDevice *associated)
{
if (device->associated == associated)
return;
if (device->associated != NULL)
g_object_unref (device->associated);
device->associated = associated;
if (device->associated != NULL)
g_object_ref (device->associated);
CLUTTER_NOTE (MISC, "Associating device %d '%s' to device %d '%s'",
clutter_input_device_get_device_id (device),
clutter_input_device_get_device_name (device),
device->associated != NULL
? clutter_input_device_get_device_id (device->associated)
: -1,
device->associated != NULL
? clutter_input_device_get_device_name (device->associated)
: "(none)");
if (device->device_mode != CLUTTER_INPUT_MODE_MASTER)
{
if (device->associated != NULL)
device->device_mode = CLUTTER_INPUT_MODE_SLAVE;
else
device->device_mode = CLUTTER_INPUT_MODE_FLOATING;
g_object_notify_by_pspec (G_OBJECT (device), obj_props[PROP_DEVICE_MODE]);
}
}
/**
* clutter_input_device_get_associated_device:
* @device: a #ClutterInputDevice
*
* Retrieves a pointer to the #ClutterInputDevice that has been
* associated to @device.
*
* If the #ClutterInputDevice:device-mode property of @device is
* set to %CLUTTER_INPUT_MODE_MASTER, this function will return
* %NULL.
*
* Return value: (transfer none): a #ClutterInputDevice, or %NULL
*
*
*/
ClutterInputDevice *
clutter_input_device_get_associated_device (ClutterInputDevice *device)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), NULL);
return device->associated;
}
/*< internal >
* clutter_input_device_select_stage_events:
* @device: a #ClutterInputDevice
* @stage: the #ClutterStage to select events on
* @event_mask: platform-specific mask of events
*
* Selects input device events on @stage.
*
* The implementation of this function depends on the backend used.
*/
void
_clutter_input_device_select_stage_events (ClutterInputDevice *device,
ClutterStage *stage,
gint event_mask)
{
ClutterInputDeviceClass *device_class;
device_class = CLUTTER_INPUT_DEVICE_GET_CLASS (device);
if (device_class->select_stage_events != NULL)
device_class->select_stage_events (device, stage, event_mask);
}
/**
* clutter_input_device_keycode_to_evdev:
* @device: A #ClutterInputDevice
* @hardware_keycode: The hardware keycode from a #ClutterKeyEvent
* @evdev_keycode: The return location for the evdev keycode
*
* Translates a hardware keycode from a #ClutterKeyEvent to the
* equivalent evdev keycode. Note that depending on the input backend
* used by Clutter this function can fail if there is no obvious
* mapping between the key codes. The hardware keycode can be taken
* from the #ClutterKeyEvent.hardware_keycode member of #ClutterKeyEvent.
*
* Return value: %TRUE if the conversion succeeded, %FALSE otherwise.
*
*
*/
gboolean
clutter_input_device_keycode_to_evdev (ClutterInputDevice *device,
guint hardware_keycode,
guint *evdev_keycode)
{
ClutterInputDeviceClass *device_class;
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
device_class = CLUTTER_INPUT_DEVICE_GET_CLASS (device);
if (device_class->keycode_to_evdev == NULL)
return FALSE;
else
return device_class->keycode_to_evdev (device,
hardware_keycode,
evdev_keycode);
}
void
_clutter_input_device_add_scroll_info (ClutterInputDevice *device,
guint index_,
ClutterScrollDirection direction,
gdouble increment)
{
ClutterScrollInfo info;
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
g_return_if_fail (index_ < clutter_input_device_get_n_axes (device));
info.axis_id = index_;
info.direction = direction;
info.increment = increment;
info.last_value_valid = FALSE;
if (device->scroll_info == NULL)
{
device->scroll_info = g_array_new (FALSE,
FALSE,
sizeof (ClutterScrollInfo));
}
g_array_append_val (device->scroll_info, info);
}
gboolean
_clutter_input_device_get_scroll_delta (ClutterInputDevice *device,
guint index_,
gdouble value,
ClutterScrollDirection *direction_p,
gdouble *delta_p)
{
guint i;
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), FALSE);
g_return_val_if_fail (index_ < clutter_input_device_get_n_axes (device), FALSE);
if (device->scroll_info == NULL)
return FALSE;
for (i = 0; i < device->scroll_info->len; i++)
{
ClutterScrollInfo *info = &g_array_index (device->scroll_info,
ClutterScrollInfo,
i);
if (info->axis_id == index_)
{
if (direction_p != NULL)
*direction_p = info->direction;
if (delta_p != NULL)
*delta_p = 0.0;
if (info->last_value_valid)
{
if (delta_p != NULL)
{
*delta_p = (value - info->last_value)
/ info->increment;
}
info->last_value = value;
}
else
{
info->last_value = value;
info->last_value_valid = TRUE;
}
return TRUE;
}
}
return FALSE;
}
void
_clutter_input_device_reset_scroll_info (ClutterInputDevice *device)
{
guint i;
if (device->scroll_info == NULL)
return;
for (i = 0; i < device->scroll_info->len; i++)
{
ClutterScrollInfo *info = &g_array_index (device->scroll_info,
ClutterScrollInfo,
i);
info->last_value_valid = FALSE;
}
}
static void
on_grab_sequence_actor_destroy (ClutterActor *actor,
ClutterInputDevice *device)
{
ClutterEventSequence *sequence =
g_hash_table_lookup (device->inv_sequence_grab_actors, actor);
if (sequence != NULL)
{
g_hash_table_remove (device->sequence_grab_actors, sequence);
g_hash_table_remove (device->inv_sequence_grab_actors, actor);
}
}
/**
* clutter_input_device_sequence_grab:
* @device: a #ClutterInputDevice
* @sequence: a #ClutterEventSequence
* @actor: a #ClutterActor
*
* Acquires a grab on @actor for the given @device and the given touch
* @sequence.
*
* Any touch event coming from @device and from @sequence will be
* delivered to @actor, bypassing the usual event delivery mechanism,
* until the grab is released by calling
* clutter_input_device_sequence_ungrab().
*
* The grab is client-side: even if the windowing system used by the Clutter
* backend has the concept of "device grabs", Clutter will not use them.
*
*
*/
void
clutter_input_device_sequence_grab (ClutterInputDevice *device,
ClutterEventSequence *sequence,
ClutterActor *actor)
{
ClutterActor *grab_actor;
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
g_return_if_fail (CLUTTER_IS_ACTOR (actor));
if (device->sequence_grab_actors == NULL)
{
grab_actor = NULL;
device->sequence_grab_actors = g_hash_table_new (NULL, NULL);
device->inv_sequence_grab_actors = g_hash_table_new (NULL, NULL);
}
else
{
grab_actor = g_hash_table_lookup (device->sequence_grab_actors, sequence);
}
if (grab_actor != NULL)
{
g_signal_handlers_disconnect_by_func (grab_actor,
G_CALLBACK (on_grab_sequence_actor_destroy),
device);
g_hash_table_remove (device->sequence_grab_actors, sequence);
g_hash_table_remove (device->inv_sequence_grab_actors, grab_actor);
}
g_hash_table_insert (device->sequence_grab_actors, sequence, actor);
g_hash_table_insert (device->inv_sequence_grab_actors, actor, sequence);
g_signal_connect (actor,
"destroy",
G_CALLBACK (on_grab_sequence_actor_destroy),
device);
}
/**
* clutter_input_device_sequence_ungrab:
* @device: a #ClutterInputDevice
* @sequence: a #ClutterEventSequence
*
* Releases the grab on the @device for the given @sequence, if one is
* in place.
*
*
*/
void
clutter_input_device_sequence_ungrab (ClutterInputDevice *device,
ClutterEventSequence *sequence)
{
ClutterActor *grab_actor;
g_return_if_fail (CLUTTER_IS_INPUT_DEVICE (device));
if (device->sequence_grab_actors == NULL)
return;
grab_actor = g_hash_table_lookup (device->sequence_grab_actors, sequence);
if (grab_actor == NULL)
return;
g_signal_handlers_disconnect_by_func (grab_actor,
G_CALLBACK (on_grab_sequence_actor_destroy),
device);
g_hash_table_remove (device->sequence_grab_actors, sequence);
g_hash_table_remove (device->inv_sequence_grab_actors, grab_actor);
if (g_hash_table_size (device->sequence_grab_actors) == 0)
{
g_hash_table_destroy (device->sequence_grab_actors);
device->sequence_grab_actors = NULL;
g_hash_table_destroy (device->inv_sequence_grab_actors);
device->inv_sequence_grab_actors = NULL;
}
}
/**
* clutter_input_device_sequence_get_grabbed_actor:
* @device: a #ClutterInputDevice
* @sequence: a #ClutterEventSequence
*
* Retrieves a pointer to the #ClutterActor currently grabbing the
* touch events coming from @device given the @sequence.
*
* Return value: (transfer none): a #ClutterActor, or %NULL
*
*
*/
ClutterActor *
clutter_input_device_sequence_get_grabbed_actor (ClutterInputDevice *device,
ClutterEventSequence *sequence)
{
g_return_val_if_fail (CLUTTER_IS_INPUT_DEVICE (device), NULL);
if (device->sequence_grab_actors == NULL)
return NULL;
return g_hash_table_lookup (device->sequence_grab_actors, sequence);
}