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mutter-performance-source/clutter/clutter-interval.h
Emmanuele Bassi af84d97fca interval: Add a pointer variant to compute_value()
ClutterInterval.compute_value() computes the new value given a progress
and copies it to a given GValue. Since most of the time we want to pass
that very same value to another function that copies it again, we should
have a compute_value() variant that stores that computed value inside
ClutterInterval and returns a pointer to it. This way we initialize the
result GValue just once and we never copy it, as long as the Interval
instance is valid.
2010-05-24 15:06:14 +01:00

165 lines
6.5 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2008 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:
* Emmanuele Bassi <ebassi@linux.intel.com>
*/
#if !defined(__CLUTTER_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
#error "Only <clutter/clutter.h> can be included directly."
#endif
#ifndef __CLUTTER_INTERVAL_H__
#define __CLUTTER_INTERVAL_H__
#include <glib-object.h>
G_BEGIN_DECLS
#define CLUTTER_TYPE_INTERVAL (clutter_interval_get_type ())
#define CLUTTER_INTERVAL(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), CLUTTER_TYPE_INTERVAL, ClutterInterval))
#define CLUTTER_IS_INTERVAL(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CLUTTER_TYPE_INTERVAL))
#define CLUTTER_INTERVAL_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_INTERVAL, ClutterIntervalClass))
#define CLUTTER_IS_INTERVAL_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_INTERVAL))
#define CLUTTER_INTERVAL_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_INTERVAL, ClutterIntervalClass))
typedef struct _ClutterInterval ClutterInterval;
typedef struct _ClutterIntervalPrivate ClutterIntervalPrivate;
typedef struct _ClutterIntervalClass ClutterIntervalClass;
/**
* ClutterProgressFunc:
* @a: the initial value of an interval
* @b: the final value of an interval
* @progress: the progress factor, between 0 and 1
* @retval: the value used to store the progress
*
* Prototype of the progress function used to compute the value
* between the two ends @a and @b of an interval depending on
* the value of @progress.
*
* The #GValue in @retval is already initialized with the same
* type as @a and @b.
*
* This function will be called by #ClutterInterval if the
* type of the values of the interval was registered using
* clutter_interval_register_progress_func().
*
* Return value: %TRUE if the function successfully computed
* the value and stored it inside @retval
*
* Since: 1.0
*/
typedef gboolean (* ClutterProgressFunc) (const GValue *a,
const GValue *b,
gdouble progress,
GValue *retval);
/**
* ClutterInterval:
*
* The #ClutterInterval structure contains only private data and should
* be accessed using the provided functions.
*
* Since: 1.0
*/
struct _ClutterInterval
{
/*< private >*/
GInitiallyUnowned parent_instance;
ClutterIntervalPrivate *priv;
};
/**
* ClutterIntervalClass:
* @validate: virtual function for validating an interval
* using a #GParamSpec
* @compute_value: virtual function for computing the value
* inside an interval using an adimensional factor between 0 and 1
*
* The #ClutterIntervalClass contains only private data.
*
* Since: 1.0
*/
struct _ClutterIntervalClass
{
/*< private >*/
GInitiallyUnownedClass parent_class;
/*< public >*/
gboolean (* validate) (ClutterInterval *interval,
GParamSpec *pspec);
gboolean (* compute_value) (ClutterInterval *interval,
gdouble factor,
GValue *value);
/*< private >*/
/* padding for future expansion */
void (*_clutter_reserved1) (void);
void (*_clutter_reserved2) (void);
void (*_clutter_reserved3) (void);
void (*_clutter_reserved4) (void);
void (*_clutter_reserved5) (void);
void (*_clutter_reserved6) (void);
};
GType clutter_interval_get_type (void) G_GNUC_CONST;
ClutterInterval *clutter_interval_new (GType gtype,
...);
ClutterInterval *clutter_interval_new_with_values (GType gtype,
const GValue *initial,
const GValue *final);
ClutterInterval *clutter_interval_clone (ClutterInterval *interval);
GType clutter_interval_get_value_type (ClutterInterval *interval);
void clutter_interval_set_initial_value (ClutterInterval *interval,
const GValue *value);
void clutter_interval_get_initial_value (ClutterInterval *interval,
GValue *value);
GValue * clutter_interval_peek_initial_value (ClutterInterval *interval);
void clutter_interval_set_final_value (ClutterInterval *interval,
const GValue *value);
void clutter_interval_get_final_value (ClutterInterval *interval,
GValue *value);
GValue * clutter_interval_peek_final_value (ClutterInterval *interval);
void clutter_interval_set_interval (ClutterInterval *interval,
...);
void clutter_interval_get_interval (ClutterInterval *interval,
...);
gboolean clutter_interval_validate (ClutterInterval *interval,
GParamSpec *pspec);
gboolean clutter_interval_compute_value (ClutterInterval *interval,
gdouble factor,
GValue *value);
G_CONST_RETURN GValue *clutter_interval_compute (ClutterInterval *interval,
gdouble factor);
void clutter_interval_register_progress_func (GType value_type,
ClutterProgressFunc func);
G_END_DECLS
#endif /* __CLUTTER_INTERVAL_H__ */