mutter/clutter/clutter-master-clock.c
Owen W. Taylor 3ab303b662 Only advance the master clock before drawing a frame
Remove code to advance the master clock after drawing a frame; if
there are any running timelines the master clock will do another
frame by itself, and the clock will be advanced before running
that frame.

With this change, there is no point in queueing an extra frame
redraw after completing a timeline, since we are always advancing
the timeline *before* redrawing, so remove that code as well.
(This does mean that calling clutter_timeline_stop() won't implicitly
cause the stage to be redrawn; this doesn't seem like something
an app should rely on in any case.)

http://bugzilla.openedhand.com/show_bug.cgi?id=1637

Signed-off-by: Emmanuele Bassi <ebassi@linux.intel.com>
2009-06-09 15:03:55 +01:00

415 lines
12 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Authored By: Emmanuele Bassi <ebassi@linux.intel.com>
*
* Copyright (C) 2009 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/>.
*/
/*
* SECTION:clutter-master-clock
* @short_description: The master clock for all animations
*
* The #ClutterMasterClock class is responsible for advancing all
* #ClutterTimelines when a stage is being redrawn. The master clock
* makes sure that the scenegraph is always integrally updated before
* painting it.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "clutter-master-clock.h"
#include "clutter-debug.h"
#include "clutter-private.h"
#define CLUTTER_MASTER_CLOCK_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_MASTER_CLOCK, ClutterMasterClockClass))
#define CLUTTER_IS_MASTER_CLOCK_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_MASTER_CLOCK))
#define CLUTTER_MASTER_CLASS_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_MASTER_CLOCK, ClutterMasterClockClass))
typedef struct _ClutterClockSource ClutterClockSource;
typedef struct _ClutterMasterClockClass ClutterMasterClockClass;
struct _ClutterMasterClock
{
GObject parent_instance;
/* the list of timelines handled by the clock */
GSList *timelines;
/* the previous state of the clock, used to compute
* the delta
*/
GTimeVal prev_tick;
gulong msecs_delta;
/* an idle source, used by the Master Clock to queue
* a redraw on the stage and drive the animations
*/
GSource *source;
};
struct _ClutterMasterClockClass
{
GObjectClass parent_class;
};
struct _ClutterClockSource
{
GSource source;
ClutterMasterClock *master_clock;
};
static void on_timeline_started (ClutterTimeline *timeline,
ClutterMasterClock *master_clock);
static gboolean clutter_clock_prepare (GSource *source,
gint *timeout);
static gboolean clutter_clock_check (GSource *source);
static gboolean clutter_clock_dispatch (GSource *source,
GSourceFunc callback,
gpointer user_data);
static ClutterMasterClock *default_clock = NULL;
static GSourceFuncs clock_funcs = {
clutter_clock_prepare,
clutter_clock_check,
clutter_clock_dispatch,
NULL
};
G_DEFINE_TYPE (ClutterMasterClock, clutter_master_clock, G_TYPE_OBJECT);
/*
* has_running_timeline:
* @master_clock: a #ClutterMasterClock
* @filter: a #ClutterTimeline or %NULL
*
* Checks if @master_clock has any running timeline; if @filter
* is not %NULL then the timeline will be filtered from the
* list of timelines held by @master_clock
*
* Return value: %TRUE if the #ClutterMasterClock has at least
* one running timeline
*/
static gboolean
has_running_timeline (ClutterMasterClock *master_clock,
ClutterTimeline *filter)
{
GSList *l;
if (master_clock->timelines == NULL)
return FALSE;
for (l = master_clock->timelines; l != NULL; l = l->next)
{
/* if we get a timeline then we should filter it
* from the list of timelines we want to check
*/
if (filter != NULL && filter == l->data)
continue;
if (clutter_timeline_is_playing (l->data))
return TRUE;
}
return FALSE;
}
/*
* clutter_clock_source_new:
* @master_clock: a #ClutterMasterClock for the source
*
* The #ClutterClockSource is an idle GSource that will queue a redraw
* if @master_clock has at least a running #ClutterTimeline. The redraw
* will cause @master_clock to advance all timelines, thus advancing all
* animations as well.
*
* Return value: the newly created #GSource
*/
static GSource *
clutter_clock_source_new (ClutterMasterClock *master_clock)
{
GSource *source = g_source_new (&clock_funcs, sizeof (ClutterClockSource));
ClutterClockSource *clock_source = (ClutterClockSource *) source;
clock_source->master_clock = master_clock;
return source;
}
static gboolean
clutter_clock_prepare (GSource *source,
gint *timeout)
{
ClutterClockSource *clock_source = (ClutterClockSource *) source;
ClutterMasterClock *master_clock = clock_source->master_clock;
gboolean retval;
/* just like an idle source, we are ready if nothing else is */
*timeout = -1;
retval = has_running_timeline (master_clock, NULL);
return retval;
}
static gboolean
clutter_clock_check (GSource *source)
{
ClutterClockSource *clock_source = (ClutterClockSource *) source;
ClutterMasterClock *master_clock = clock_source->master_clock;
gboolean retval;
retval = has_running_timeline (master_clock, NULL);
return retval;
}
static gboolean
clutter_clock_dispatch (GSource *source,
GSourceFunc callback,
gpointer user_data)
{
ClutterStageManager *stage_manager = clutter_stage_manager_get_default ();
const GSList *stages, *l;
CLUTTER_NOTE (SCHEDULER, "Master clock [tick]");
stages = clutter_stage_manager_peek_stages (stage_manager);
/* queue a redraw for each stage; this will advance each timeline
* held by the master clock of the amount of milliseconds elapsed
* since the last redraw
*/
for (l = stages; l != NULL; l = l->next)
clutter_actor_queue_redraw (l->data);
return TRUE;
}
static void
timeline_weak_ref (gpointer data,
GObject *object_pointer)
{
ClutterMasterClock *master_clock = data;
master_clock->timelines =
g_slist_remove (master_clock->timelines, object_pointer);
if (master_clock->timelines == NULL)
master_clock->prev_tick.tv_sec = 0;
}
static void
clutter_master_clock_finalize (GObject *gobject)
{
ClutterMasterClock *master_clock = CLUTTER_MASTER_CLOCK (gobject);
GSList *l;
for (l = master_clock->timelines; l != NULL; l = l->next)
{
ClutterTimeline *timeline = l->data;
g_object_weak_unref (G_OBJECT (timeline),
timeline_weak_ref,
master_clock);
g_signal_handlers_disconnect_by_func (timeline,
G_CALLBACK (on_timeline_started),
master_clock);
}
g_slist_free (master_clock->timelines);
G_OBJECT_CLASS (clutter_master_clock_parent_class)->finalize (gobject);
}
static void
clutter_master_clock_class_init (ClutterMasterClockClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->finalize = clutter_master_clock_finalize;
}
static void
clutter_master_clock_init (ClutterMasterClock *self)
{
GSource *source;
source = clutter_clock_source_new (self);
self->source = source;
g_source_set_priority (source, CLUTTER_PRIORITY_REDRAW);
g_source_set_can_recurse (source, FALSE);
g_source_attach (source, NULL);
}
/*
* _clutter_master_clock_get_default:
*
* Retrieves the default master clock. If this function has never
* been called before, the default master clock is created.
*
* Return value: the default master clock. The returned object is
* owned by Clutter and should not be modified or freed
*/
ClutterMasterClock *
_clutter_master_clock_get_default (void)
{
if (G_LIKELY (default_clock != NULL))
return default_clock;
default_clock = g_object_new (CLUTTER_TYPE_MASTER_CLOCK, NULL);
return default_clock;
}
static void
on_timeline_started (ClutterTimeline *timeline,
ClutterMasterClock *master_clock)
{
/* we want to reset the prev_tick if this is the first
* timeline; since timeline is playing we need to filter
* it out, otherwise has_running_timeline() will return
* TRUE and prev_tick will not be unset
*/
if (!has_running_timeline (master_clock, timeline))
master_clock->prev_tick.tv_sec = 0;
}
/*
* _clutter_master_clock_add_timeline:
* @master_clock: a #ClutterMasterClock
* @timeline: a #ClutterTimeline
*
* Adds @timeline to the list of timelines held by the master
* clock. This function should be called during the instance
* creation phase of the timeline.
*/
void
_clutter_master_clock_add_timeline (ClutterMasterClock *master_clock,
ClutterTimeline *timeline)
{
gboolean is_first = FALSE;
if (g_slist_find (master_clock->timelines, timeline))
return;
is_first = (master_clock->timelines == NULL) ? TRUE : FALSE;
master_clock->timelines = g_slist_prepend (master_clock->timelines,
timeline);
g_object_weak_ref (G_OBJECT (timeline),
timeline_weak_ref,
master_clock);
g_signal_connect (timeline, "started",
G_CALLBACK (on_timeline_started),
master_clock);
}
/*
* _clutter_master_clock_remove_timeline:
* @master_clock: a #ClutterMasterClock
* @timeline: a #ClutterTimeline
*
* Removes @timeline from the list of timelines held by the
* master clock. This function should be called during the
* #ClutterTimeline finalization.
*/
void
_clutter_master_clock_remove_timeline (ClutterMasterClock *master_clock,
ClutterTimeline *timeline)
{
if (!g_slist_find (master_clock->timelines, timeline))
return;
master_clock->timelines = g_slist_remove (master_clock->timelines,
timeline);
g_object_weak_unref (G_OBJECT (timeline),
timeline_weak_ref,
master_clock);
g_signal_handlers_disconnect_by_func (timeline,
G_CALLBACK (on_timeline_started),
master_clock);
/* last timeline: unset the prev_tick so that we can start
* from scratch when we add a new timeline
*/
if (master_clock->timelines == NULL)
master_clock->prev_tick.tv_sec = 0;
}
/*
* _clutter_master_clock_advance:
* @master_clock: a #ClutterMasterClock
*
* Advances all the timelines held by the master clock. This function
* should be called before calling clutter_redraw() to make sure that
* all the timelines are advanced and the scene is updated.
*/
void
_clutter_master_clock_advance (ClutterMasterClock *master_clock)
{
GTimeVal cur_tick = { 0, };
gulong msecs;
GSList *l;
g_return_if_fail (CLUTTER_IS_MASTER_CLOCK (master_clock));
if (master_clock->timelines == NULL)
return;
g_get_current_time (&cur_tick);
if (master_clock->prev_tick.tv_sec == 0)
master_clock->prev_tick = cur_tick;
msecs = (cur_tick.tv_sec - master_clock->prev_tick.tv_sec) * 1000
+ (cur_tick.tv_usec - master_clock->prev_tick.tv_usec) / 1000;
if (msecs == 0)
return;
CLUTTER_NOTE (SCHEDULER, "Advancing %d timelines by %lu milliseconds",
g_slist_length (master_clock->timelines),
msecs);
for (l = master_clock->timelines; l != NULL; l = l->next)
{
ClutterTimeline *timeline = l->data;
if (clutter_timeline_is_playing (timeline))
clutter_timeline_advance_delta (timeline, msecs);
}
/* store the previous state so that we can use
* it for the next advancement
*/
master_clock->msecs_delta = msecs;
master_clock->prev_tick = cur_tick;
}