/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2010 Intel Corporation.
* Copyright (C) 2011 Robert Bosch Car Multimedia GmbH.
* Copyright (C) 2012 Intel Corporation.
*
* 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:
* Tomeu Vizoso <tomeu.vizoso@collabora.co.uk>
*/
/**
* SECTION:clutter-gesture-action
* @Title: ClutterGestureAction
* @Short_Description: Action for gesture gestures
*
* #ClutterGestureAction is a sub-class of #ClutterAction that implements
* the logic for recognizing gesture gestures. It listens for low level events
* such as #ClutterButtonEvent and #ClutterMotionEvent on the stage to raise
* the #ClutterGestureAction::gesture-begin, #ClutterGestureAction::gesture-progress,
* and #ClutterGestureAction::gesture-end signals.
*
* To use #ClutterGestureAction you just need to apply it to a #ClutterActor
* using clutter_actor_add_action() and connect to the signals:
*
* |[
* ClutterAction *action = clutter_gesture_action_new ();
*
* clutter_actor_add_action (actor, action);
*
* g_signal_connect (action, "gesture-begin", G_CALLBACK (on_gesture_begin), NULL);
* g_signal_connect (action, "gesture-progress", G_CALLBACK (on_gesture_progress), NULL);
* g_signal_connect (action, "gesture-end", G_CALLBACK (on_gesture_end), NULL);
* ]|
*
* Since: 1.8
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "clutter-gesture-action.h"
#include "clutter-debug.h"
#include "clutter-enum-types.h"
#include "clutter-marshal.h"
#include "clutter-private.h"
#include <math.h>
#define MAX_GESTURE_POINTS (10)
#define FLOAT_EPSILON (1e-15)
typedef struct
{
ClutterInputDevice *device;
ClutterEventSequence *sequence;
gfloat press_x, press_y;
gint64 last_motion_time;
gfloat last_motion_x, last_motion_y;
gint64 last_delta_time;
gfloat last_delta_x, last_delta_y;
gfloat release_x, release_y;
} GesturePoint;
struct _ClutterGestureActionPrivate
{
ClutterActor *stage;
gint requested_nb_points;
GArray *points;
guint actor_capture_id;
gulong stage_capture_id;
guint in_gesture : 1;
};
enum
{
GESTURE_BEGIN,
GESTURE_PROGRESS,
GESTURE_END,
GESTURE_CANCEL,
LAST_SIGNAL
};
static guint gesture_signals[LAST_SIGNAL] = { 0, };
G_DEFINE_TYPE (ClutterGestureAction, clutter_gesture_action, CLUTTER_TYPE_ACTION);
static GesturePoint *
gesture_register_point (ClutterGestureAction *action, ClutterEvent *event)
{
ClutterGestureActionPrivate *priv = action->priv;
GesturePoint *point = NULL;
if (priv->points->len >= MAX_GESTURE_POINTS)
return NULL;
g_array_set_size (priv->points, priv->points->len + 1);
point = &g_array_index (priv->points, GesturePoint, priv->points->len - 1);
point->device = clutter_event_get_device (event);
clutter_event_get_coords (event, &point->press_x, &point->press_y);
point->last_motion_x = point->press_x;
point->last_motion_y = point->press_y;
point->last_motion_time = clutter_event_get_time (event);
point->last_delta_x = point->last_delta_y = 0;
point->last_delta_time = 0;
if (clutter_event_type (event) != CLUTTER_BUTTON_PRESS)
point->sequence = clutter_event_get_event_sequence (event);
else
point->sequence = NULL;
return point;
}
static GesturePoint *
gesture_find_point (ClutterGestureAction *action,
ClutterEvent *event,
gint *position)
{
ClutterGestureActionPrivate *priv = action->priv;
GesturePoint *point = NULL;
ClutterEventType type = clutter_event_type (event);
ClutterInputDevice *device = clutter_event_get_device (event);
ClutterEventSequence *sequence = NULL;
gint i;
if ((type != CLUTTER_BUTTON_PRESS) &&
(type != CLUTTER_BUTTON_RELEASE) &&
(type != CLUTTER_MOTION))
sequence = clutter_event_get_event_sequence (event);
for (i = 0; i < priv->points->len; i++)
{
if ((g_array_index (priv->points, GesturePoint, i).device == device) &&
(g_array_index (priv->points, GesturePoint, i).sequence == sequence))
{
if (position != NULL)
*position = i;
point = &g_array_index (priv->points, GesturePoint, i);
break;
}
}
return point;
}
static void
gesture_unregister_point (ClutterGestureAction *action, gint position)
{
ClutterGestureActionPrivate *priv = action->priv;
g_array_remove_index (priv->points, position);
}
static void
cancel_gesture (ClutterGestureAction *action)
{
ClutterGestureActionPrivate *priv = action->priv;
ClutterActor *actor;
priv->in_gesture = FALSE;
g_signal_handler_disconnect (priv->stage, priv->stage_capture_id);
priv->stage_capture_id = 0;
actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (action));
g_signal_emit (action, gesture_signals[GESTURE_CANCEL], 0, actor);
}
static gboolean
stage_captured_event_cb (ClutterActor *stage,
ClutterEvent *event,
ClutterGestureAction *action)
{
ClutterGestureActionPrivate *priv = action->priv;
ClutterActor *actor;
gint position;
gboolean return_value;
GesturePoint *point;
gfloat motion_x, motion_y;
gint64 time;
if ((point = gesture_find_point (action, event, &position)) == NULL)
return CLUTTER_EVENT_PROPAGATE;
actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (action));
switch (clutter_event_type (event))
{
case CLUTTER_MOTION:
{
ClutterModifierType mods = clutter_event_get_state (event);
/* we might miss a button-release event in case of grabs,
* so we need to check whether the button is still down
* during a motion event
*/
if (!(mods & CLUTTER_BUTTON1_MASK))
{
cancel_gesture (action);
return CLUTTER_EVENT_PROPAGATE;
}
}
/* Follow same code path as a touch event update */
case CLUTTER_TOUCH_UPDATE:
clutter_event_get_coords (event,
&motion_x,
&motion_y);
if (priv->points->len < priv->requested_nb_points)
return CLUTTER_EVENT_PROPAGATE;
if (!priv->in_gesture)
{
gint drag_threshold;
ClutterSettings *settings = clutter_settings_get_default ();
g_object_get (settings,
"dnd-drag-threshold", &drag_threshold,
NULL);
if ((ABS (point->press_y - motion_y) >= drag_threshold) ||
(ABS (point->press_x - motion_x) >= drag_threshold))
{
priv->in_gesture = TRUE;
g_signal_emit (action, gesture_signals[GESTURE_BEGIN], 0, actor,
&return_value);
if (!return_value)
{
cancel_gesture (action);
return CLUTTER_EVENT_PROPAGATE;
}
}
else
return CLUTTER_EVENT_PROPAGATE;
}
point->last_delta_x = motion_x - point->last_motion_x;
point->last_delta_y = motion_y - point->last_motion_y;
point->last_motion_x = motion_x;
point->last_motion_y = motion_y;
time = clutter_event_get_time (event);
point->last_delta_time = time - point->last_motion_time;
point->last_motion_time = time;
g_signal_emit (action, gesture_signals[GESTURE_PROGRESS], 0, actor,
&return_value);
if (!return_value)
{
cancel_gesture (action);
return CLUTTER_EVENT_PROPAGATE;
}
break;
case CLUTTER_BUTTON_RELEASE:
case CLUTTER_TOUCH_END:
{
clutter_event_get_coords (event, &point->release_x, &point->release_y);
if (priv->in_gesture &&
((priv->points->len - 1) < priv->requested_nb_points))
{
/* Treat the release event as the continuation of the last motion,
* in case the user keeps the pointer still for a while before
* releasing it. */
time = clutter_event_get_time (event);
point->last_delta_time += time - point->last_motion_time;
priv->in_gesture = FALSE;
g_signal_emit (action, gesture_signals[GESTURE_END], 0, actor);
}
gesture_unregister_point (action, position);
}
break;
case CLUTTER_TOUCH_CANCEL:
{
if (priv->in_gesture)
{
priv->in_gesture = FALSE;
cancel_gesture (action);
}
gesture_unregister_point (action, position);
}
break;
default:
break;
}
if (priv->points->len == 0)
{
g_signal_handler_disconnect (priv->stage, priv->stage_capture_id);
priv->stage_capture_id = 0;
}
return CLUTTER_EVENT_PROPAGATE;
}
static gboolean
actor_captured_event_cb (ClutterActor *actor,
ClutterEvent *event,
ClutterGestureAction *action)
{
ClutterGestureActionPrivate *priv = action->priv;
GesturePoint *point G_GNUC_UNUSED;
if ((clutter_event_type (event) != CLUTTER_BUTTON_PRESS) &&
(clutter_event_type (event) != CLUTTER_TOUCH_BEGIN))
return CLUTTER_EVENT_PROPAGATE;
if (!clutter_actor_meta_get_enabled (CLUTTER_ACTOR_META (action)))
return CLUTTER_EVENT_PROPAGATE;
point = gesture_register_point (action, event);
if (priv->stage == NULL)
priv->stage = clutter_actor_get_stage (actor);
if (priv->stage_capture_id == 0)
priv->stage_capture_id =
g_signal_connect_after (priv->stage, "captured-event",
G_CALLBACK (stage_captured_event_cb),
action);
return CLUTTER_EVENT_PROPAGATE;
}
static void
clutter_gesture_action_set_actor (ClutterActorMeta *meta,
ClutterActor *actor)
{
ClutterGestureActionPrivate *priv = CLUTTER_GESTURE_ACTION (meta)->priv;
ClutterActorMetaClass *meta_class =
CLUTTER_ACTOR_META_CLASS (clutter_gesture_action_parent_class);
if (priv->actor_capture_id != 0)
{
ClutterActor *old_actor = clutter_actor_meta_get_actor (meta);
if (old_actor != NULL)
g_signal_handler_disconnect (old_actor, priv->actor_capture_id);
priv->actor_capture_id = 0;
}
if (priv->stage_capture_id != 0)
{
if (priv->stage != NULL)
g_signal_handler_disconnect (priv->stage, priv->stage_capture_id);
priv->stage_capture_id = 0;
priv->stage = NULL;
}
if (actor != NULL)
{
priv->actor_capture_id =
g_signal_connect (actor, "captured-event",
G_CALLBACK (actor_captured_event_cb),
meta);
}
meta_class->set_actor (meta, actor);
}
static gboolean
default_event_handler (ClutterGestureAction *action,
ClutterActor *actor)
{
return TRUE;
}
static void
clutter_gesture_action_class_init (ClutterGestureActionClass *klass)
{
ClutterActorMetaClass *meta_class = CLUTTER_ACTOR_META_CLASS (klass);
g_type_class_add_private (klass, sizeof (ClutterGestureActionPrivate));
meta_class->set_actor = clutter_gesture_action_set_actor;
klass->gesture_begin = default_event_handler;
klass->gesture_progress = default_event_handler;
/**
* ClutterGestureAction::gesture-begin:
* @action: the #ClutterGestureAction that emitted the signal
* @actor: the #ClutterActor attached to the @action
*
* The ::gesture_begin signal is emitted when the #ClutterActor to which
* a #ClutterGestureAction has been applied starts receiving a gesture.
*
* Return value: %TRUE if the gesture should start, and %FALSE if
* the gesture should be ignored.
*
* Since: 1.8
*/
gesture_signals[GESTURE_BEGIN] =
g_signal_new (I_("gesture-begin"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (ClutterGestureActionClass, gesture_begin),
_clutter_boolean_continue_accumulator, NULL,
_clutter_marshal_BOOLEAN__OBJECT,
G_TYPE_BOOLEAN, 1,
CLUTTER_TYPE_ACTOR);
/**
* ClutterGestureAction::gesture-progress:
* @action: the #ClutterGestureAction that emitted the signal
* @actor: the #ClutterActor attached to the @action
*
* The ::gesture-progress signal is emitted for each motion event after
* the #ClutterGestureAction::gesture-begin signal has been emitted.
*
* Return value: %TRUE if the gesture should continue, and %FALSE if
* the gesture should be cancelled.
*
* Since: 1.8
*/
gesture_signals[GESTURE_PROGRESS] =
g_signal_new (I_("gesture-progress"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (ClutterGestureActionClass, gesture_progress),
_clutter_boolean_continue_accumulator, NULL,
_clutter_marshal_BOOLEAN__OBJECT,
G_TYPE_BOOLEAN, 1,
CLUTTER_TYPE_ACTOR);
/**
* ClutterGestureAction::gesture-end:
* @action: the #ClutterGestureAction that emitted the signal
* @actor: the #ClutterActor attached to the @action
*
* The ::gesture-end signal is emitted at the end of the gesture gesture,
* when the pointer's button is released
*
* This signal is emitted if and only if the #ClutterGestureAction::gesture-begin
* signal has been emitted first.
*
* Since: 1.8
*/
gesture_signals[GESTURE_END] =
g_signal_new (I_("gesture-end"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (ClutterGestureActionClass, gesture_end),
NULL, NULL,
_clutter_marshal_VOID__OBJECT,
G_TYPE_NONE, 1,
CLUTTER_TYPE_ACTOR);
/**
* ClutterGestureAction::gesture-cancel:
* @action: the #ClutterGestureAction that emitted the signal
* @actor: the #ClutterActor attached to the @action
*
* The ::gesture-cancel signal is emitted when the ongoing gesture gets
* cancelled from the #ClutterGestureAction::gesture-progress signal handler.
*
* This signal is emitted if and only if the #ClutterGestureAction::gesture-begin
* signal has been emitted first.
*
* Since: 1.8
*/
gesture_signals[GESTURE_CANCEL] =
g_signal_new (I_("gesture-cancel"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (ClutterGestureActionClass, gesture_cancel),
NULL, NULL,
_clutter_marshal_VOID__OBJECT,
G_TYPE_NONE, 1,
CLUTTER_TYPE_ACTOR);
}
static void
clutter_gesture_action_init (ClutterGestureAction *self)
{
self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, CLUTTER_TYPE_GESTURE_ACTION,
ClutterGestureActionPrivate);
self->priv->points = g_array_sized_new (FALSE, TRUE, sizeof (GesturePoint), 3);
self->priv->requested_nb_points = 1;
}
/**
* clutter_gesture_action_new:
*
* Creates a new #ClutterGestureAction instance.
*
* Return value: the newly created #ClutterGestureAction
*
* Since: 1.8
*/
ClutterAction *
clutter_gesture_action_new (void)
{
return g_object_new (CLUTTER_TYPE_GESTURE_ACTION, NULL);
}
/**
* clutter_gesture_action_get_press_coords:
* @action: a #ClutterGestureAction
* @device: currently unused, set to 0
* @press_x: (out) (allow-none): return location for the press
* event's X coordinate
* @press_y: (out) (allow-none): return location for the press
* event's Y coordinate
*
* Retrieves the coordinates, in stage space, of the press event
* that started the dragging for an specific pointer device
*
* Since: 1.8
*/
void
clutter_gesture_action_get_press_coords (ClutterGestureAction *action,
guint device,
gfloat *press_x,
gfloat *press_y)
{
g_return_if_fail (CLUTTER_IS_GESTURE_ACTION (action));
g_return_if_fail (action->priv->points->len > device);
if (press_x)
*press_x = g_array_index (action->priv->points,
GesturePoint,
device).press_x;
if (press_y)
*press_y = g_array_index (action->priv->points,
GesturePoint,
device).press_y;
}
/**
* clutter_gesture_action_get_motion_coords:
* @action: a #ClutterGestureAction
* @device: currently unused, set to 0
* @motion_x: (out) (allow-none): return location for the latest motion
* event's X coordinate
* @motion_y: (out) (allow-none): return location for the latest motion
* event's Y coordinate
*
* Retrieves the coordinates, in stage space, of the latest motion
* event during the dragging
*
* Since: 1.8
*/
void
clutter_gesture_action_get_motion_coords (ClutterGestureAction *action,
guint device,
gfloat *motion_x,
gfloat *motion_y)
{
g_return_if_fail (CLUTTER_IS_GESTURE_ACTION (action));
g_return_if_fail (action->priv->points->len > device);
if (motion_x)
*motion_x = g_array_index (action->priv->points,
GesturePoint,
device).last_motion_x;
if (motion_y)
*motion_y = g_array_index (action->priv->points,
GesturePoint,
device).last_motion_y;
}
/**
* clutter_gesture_action_get_motion_delta:
* @action: a #ClutterGestureAction
* @device: currently unused, set to 0
* @delta_x: (out) (allow-none): return location for the X axis
* component of the incremental motion delta
* @delta_y: (out) (allow-none): return location for the Y axis
* component of the incremental motion delta
*
* Retrieves the incremental delta since the last motion event
* during the dragging.
*
* Return value: the distance since last motion event
*
* Since: 1.12
*/
gfloat
clutter_gesture_action_get_motion_delta (ClutterGestureAction *action,
guint device,
gfloat *delta_x,
gfloat *delta_y)
{
gfloat d_x, d_y;
g_return_val_if_fail (CLUTTER_IS_GESTURE_ACTION (action), 0);
g_return_val_if_fail (action->priv->points->len > device, 0);
d_x = g_array_index (action->priv->points,
GesturePoint,
device).last_delta_x;
d_y = g_array_index (action->priv->points,
GesturePoint,
device).last_delta_y;
if (delta_x)
*delta_x = d_x;
if (delta_y)
*delta_y = d_y;
return sqrt ((d_x * d_x) + (d_y * d_y));
}
/**
* clutter_gesture_action_get_release_coords:
* @action: a #ClutterGestureAction
* @device: currently unused, set to 0
* @release_x: (out) (allow-none): return location for the X coordinate of
* the last release
* @release_y: (out) (allow-none): return location for the Y coordinate of
* the last release
*
* Retrieves the coordinates, in stage space, of the point where the pointer
* device was last released.
*
* Since: 1.8
*/
void
clutter_gesture_action_get_release_coords (ClutterGestureAction *action,
guint device,
gfloat *release_x,
gfloat *release_y)
{
g_return_if_fail (CLUTTER_IS_GESTURE_ACTION (action));
g_return_if_fail (action->priv->points->len > device);
if (release_x)
*release_x = g_array_index (action->priv->points,
GesturePoint,
device).release_x;
if (release_y)
*release_y = g_array_index (action->priv->points,
GesturePoint,
device).release_y;
}
/**
* clutter_gesture_action_get_velocity:
* @action: a #ClutterGestureAction
* @device: currently unused, set to 0
* @velocity_x: (out) (allow-none): return location for the latest motion
* event's X velocity
* @velocity_y: (out) (allow-none): return location for the latest motion
* event's Y velocity
*
* Retrieves the velocity, in stage pixels per microseconds, of the
* latest motion event during the dragging
*
* Since: 1.12
*/
gfloat
clutter_gesture_action_get_velocity (ClutterGestureAction *action,
guint device,
gfloat *velocity_x,
gfloat *velocity_y)
{
gfloat d_x, d_y, distance, velocity;
gint64 d_t;
g_return_val_if_fail (CLUTTER_IS_GESTURE_ACTION (action), 0);
g_return_val_if_fail (action->priv->points->len > device, 0);
distance = clutter_gesture_action_get_motion_delta (action, device,
&d_x, &d_y);
d_t = g_array_index (action->priv->points,
GesturePoint,
device).last_delta_time;
if (velocity_x)
*velocity_x = d_t > FLOAT_EPSILON ? d_x / d_t : 0;
if (velocity_y)
*velocity_y = d_t > FLOAT_EPSILON ? d_y / d_t : 0;
velocity = d_t > FLOAT_EPSILON ? distance / d_t : 0;
return velocity;
}
/**
* clutter_gesture_action_get_n_touch_points:
* @action: a #ClutterGestureAction
*
* Retrieves the number of requested points to trigger the gesture.
*
* Return value: the number of points to trigger the gesture.
*
* Since: 1.12
*/
gint
clutter_gesture_action_get_n_touch_points (ClutterGestureAction *action)
{
g_return_val_if_fail (CLUTTER_IS_GESTURE_ACTION (action), 0);
return action->priv->requested_nb_points;
}
/**
* clutter_gesture_action_set_n_touch_points:
* @action: a #ClutterGestureAction
* @nb_points: a number of points
*
* Sets the number of points needed to trigger the gesture.
*
* Since: 1.12
*/
void
clutter_gesture_action_set_n_touch_points (ClutterGestureAction *action,
gint nb_points)
{
ClutterGestureActionPrivate *priv;
g_return_if_fail (CLUTTER_IS_GESTURE_ACTION (action));
g_return_if_fail (nb_points >= 1);
priv = action->priv;
priv->requested_nb_points = nb_points;
if (priv->in_gesture)
{
if (priv->points->len < priv->requested_nb_points)
cancel_gesture (action);
}
else
{
if (priv->points->len >= priv->requested_nb_points)
{
ClutterActor *actor =
clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (action));
ClutterSettings *settings = clutter_settings_get_default ();
gint i, drag_threshold;
g_object_get (settings,
"dnd-drag-threshold", &drag_threshold,
NULL);
for (i = 0; i < priv->points->len; i++)
{
GesturePoint *point = &g_array_index (priv->points, GesturePoint, i);
if ((ABS (point->press_y - point->last_motion_y) >= drag_threshold) ||
(ABS (point->press_x - point->last_motion_x) >= drag_threshold))
{
gboolean return_value;
priv->in_gesture = TRUE;
g_signal_emit (action, gesture_signals[GESTURE_BEGIN], 0, actor,
&return_value);
if (!return_value)
cancel_gesture (action);
break;
}
}
}
}
}