mutter/clutter/clutter-master-clock.c
Emmanuele Bassi b281f2090a Store the master clock pointer in the main context
Let's try and move all singletons into ClutterMainContext.
2011-11-14 17:16:27 +00:00

597 lines
18 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"
#include "clutter-profile.h"
#include "clutter-stage-manager-private.h"
#include "clutter-stage-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 current state of the clock, in usecs */
gint64 cur_tick;
/* the previous state of the clock, in usecs, used to compute the delta */
gint64 prev_tick;
/* an idle source, used by the Master Clock to queue
* a redraw on the stage and drive the animations
*/
GSource *source;
/* If the master clock is idle that means it has
* fallen back to idle polling for timeline
* progressions and it may have been some time since
* the last real stage update.
*/
guint idle : 1;
guint ensure_next_iteration : 1;
};
struct _ClutterMasterClockClass
{
GObjectClass parent_class;
};
struct _ClutterClockSource
{
GSource source;
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 GSourceFuncs clock_funcs = {
clutter_clock_prepare,
clutter_clock_check,
clutter_clock_dispatch,
NULL
};
G_DEFINE_TYPE (ClutterMasterClock, clutter_master_clock, G_TYPE_OBJECT);
/*
* master_clock_is_running:
* @master_clock: a #ClutterMasterClock
*
* Checks if we should currently be advancing timelines or redrawing
* stages.
*
* Return value: %TRUE if the #ClutterMasterClock has at least
* one running timeline
*/
static gboolean
master_clock_is_running (ClutterMasterClock *master_clock)
{
ClutterStageManager *stage_manager = clutter_stage_manager_get_default ();
const GSList *stages, *l;
gboolean stage_free = FALSE;
stages = clutter_stage_manager_peek_stages (stage_manager);
/* If all of the stages are busy waiting for a swap-buffers to complete
* then we stop the master clock... */
for (l = stages; l != NULL; l = l->next)
{
if (_clutter_stage_get_pending_swaps (l->data) == 0)
{
stage_free = TRUE;
break;
}
}
if (!stage_free)
return FALSE;
if (master_clock->timelines)
return TRUE;
for (l = stages; l; l = l->next)
{
if (_clutter_stage_has_queued_events (l->data) ||
_clutter_stage_needs_update (l->data))
return TRUE;
}
if (master_clock->ensure_next_iteration)
{
master_clock->ensure_next_iteration = FALSE;
return TRUE;
}
return FALSE;
}
/*
* master_clock_next_frame_delay:
* @master_clock: a #ClutterMasterClock
*
* Computes the number of delay before we need to draw the next frame.
*
* Return value: -1 if there is no next frame pending, otherwise the
* number of millseconds before the we need to draw the next frame
*/
static gint
master_clock_next_frame_delay (ClutterMasterClock *master_clock)
{
gint64 now, next;
if (!master_clock_is_running (master_clock))
return -1;
/* When we have sync-to-vblank, we count on swap-buffer requests (or
* swap-buffer-complete events if supported in the backend) to throttle our
* frame rate so no additional delay is needed to start the next frame.
*
* If the master-clock has become idle due to no timeline progression causing
* redraws then we can no longer rely on vblank synchronization because the
* last real stage update/redraw may have happened a long time ago and so we
* fallback to polling for timeline progressions every 1/frame_rate seconds.
*
* (NB: if there aren't even any timelines running then the master clock will
* be completely stopped in master_clock_is_running())
*/
if (clutter_feature_available (CLUTTER_FEATURE_SYNC_TO_VBLANK) &&
!master_clock->idle)
{
CLUTTER_NOTE (SCHEDULER, "vblank available and updated stages");
return 0;
}
if (master_clock->prev_tick == 0)
{
/* If we weren't previously running, then draw the next frame
* immediately
*/
CLUTTER_NOTE (SCHEDULER, "draw the first frame immediately");
return 0;
}
/* Otherwise, wait at least 1/frame_rate seconds since we last
* started a frame
*/
#if GLIB_CHECK_VERSION (2, 27, 3)
now = g_source_get_time (master_clock->source);
#else
{
GTimeVal source_time;
g_source_get_current_time (master_clock->source, &source_time);
now = source_time.tv_sec * 1000000L + source_time.tv_usec;
}
#endif
next = master_clock->prev_tick;
/* If time has gone backwards then there's no way of knowing how
long we should wait so let's just dispatch immediately */
if (now <= next)
{
CLUTTER_NOTE (SCHEDULER, "Time has gone backwards");
return 0;
}
next += (1000000L / clutter_get_default_frame_rate ());
if (next <= now)
{
CLUTTER_NOTE (SCHEDULER, "Less than %lu microsecs",
1000000L / (gulong) clutter_get_default_frame_rate ());
return 0;
}
else
{
CLUTTER_NOTE (SCHEDULER, "Waiting %" G_GINT64_FORMAT " msecs",
(next - now) / 1000);
return (next - now) / 1000;
}
}
/*
* 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;
g_source_set_name (source, "Clutter master clock");
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;
int delay;
clutter_threads_enter ();
if (G_UNLIKELY (clutter_paint_debug_flags &
CLUTTER_DEBUG_CONTINUOUS_REDRAW))
{
ClutterStageManager *stage_manager = clutter_stage_manager_get_default ();
const GSList *stages, *l;
stages = clutter_stage_manager_peek_stages (stage_manager);
/* Queue a full redraw on all of the stages */
for (l = stages; l != NULL; l = l->next)
clutter_actor_queue_redraw (l->data);
}
delay = master_clock_next_frame_delay (master_clock);
clutter_threads_leave ();
*timeout = delay;
return delay == 0;
}
static gboolean
clutter_clock_check (GSource *source)
{
ClutterClockSource *clock_source = (ClutterClockSource *) source;
ClutterMasterClock *master_clock = clock_source->master_clock;
int delay;
clutter_threads_enter ();
delay = master_clock_next_frame_delay (master_clock);
clutter_threads_leave ();
return delay == 0;
}
static gboolean
clutter_clock_dispatch (GSource *source,
GSourceFunc callback,
gpointer user_data)
{
ClutterClockSource *clock_source = (ClutterClockSource *) source;
ClutterMasterClock *master_clock = clock_source->master_clock;
ClutterStageManager *stage_manager = clutter_stage_manager_get_default ();
gboolean stages_updated = FALSE;
GSList *stages, *l;
CLUTTER_STATIC_TIMER (master_dispatch_timer,
"Mainloop",
"Master Clock",
"Master clock dispatch",
0);
CLUTTER_STATIC_TIMER (master_event_process,
"Master Clock",
"Event Processing",
"The time spent processing events on all stages",
0);
CLUTTER_TIMER_START (_clutter_uprof_context, master_dispatch_timer);
CLUTTER_NOTE (SCHEDULER, "Master clock [tick]");
clutter_threads_enter ();
/* Get the time to use for this frame */
#if GLIB_CHECK_VERSION (2, 27, 3)
master_clock->cur_tick = g_source_get_time (source);
#else
{
GTimeVal source_time;
g_source_get_current_time (source, &source_time);
master_clock->cur_tick = source_time.tv_sec * 1000000L
+ source_time.tv_usec;
}
#endif
/* We need to protect ourselves against stages being destroyed during
* event handling
*/
stages = clutter_stage_manager_list_stages (stage_manager);
g_slist_foreach (stages, (GFunc) g_object_ref, NULL);
CLUTTER_TIMER_START (_clutter_uprof_context, master_event_process);
master_clock->idle = FALSE;
/* Process queued events */
for (l = stages; l != NULL; l = l->next)
{
/* NB: If a stage is busy waiting for a swap-buffers completion then
* we don't process its events so we can maximize the benefits of
* motion compression, and avoid multiple picks per frame.
*/
if (_clutter_stage_get_pending_swaps (l->data) == 0)
_clutter_stage_process_queued_events (l->data);
}
CLUTTER_TIMER_STOP (_clutter_uprof_context, master_event_process);
_clutter_master_clock_advance (master_clock);
_clutter_run_repaint_functions ();
/* Update any stage that needs redraw/relayout after the clock
* is advanced.
*/
for (l = stages; l != NULL; l = l->next)
{
/* If a stage has a swap-buffers pending we don't want to draw to it
* in case the driver may block the CPU while it waits for the next
* backbuffer to become available.
*
* TODO: We should be able to identify if we are running triple or N
* buffered and in these cases we can still draw if there is 1 swap
* pending so we can hopefully always be ready to swap for the next
* vblank and really match the vsync frequency.
*/
if (_clutter_stage_get_pending_swaps (l->data) == 0)
stages_updated |= _clutter_stage_do_update (l->data);
}
/* The master clock goes idle if no stages were updated and falls back
* to polling for timeline progressions... */
if (!stages_updated)
master_clock->idle = TRUE;
g_slist_foreach (stages, (GFunc) g_object_unref, NULL);
g_slist_free (stages);
master_clock->prev_tick = master_clock->cur_tick;
clutter_threads_leave ();
CLUTTER_TIMER_STOP (_clutter_uprof_context, master_dispatch_timer);
return TRUE;
}
static void
clutter_master_clock_finalize (GObject *gobject)
{
ClutterMasterClock *master_clock = CLUTTER_MASTER_CLOCK (gobject);
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;
self->idle = FALSE;
self->ensure_next_iteration = FALSE;
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)
{
ClutterMainContext *context = _clutter_context_get_default ();
if (G_UNLIKELY (context->master_clock == NULL))
context->master_clock = g_object_new (CLUTTER_TYPE_MASTER_CLOCK, NULL);
return context->master_clock;
}
/*
* _clutter_master_clock_add_timeline:
* @master_clock: a #ClutterMasterClock
* @timeline: a #ClutterTimeline
*
* Adds @timeline to the list of playing timelines held by the master
* clock.
*/
void
_clutter_master_clock_add_timeline (ClutterMasterClock *master_clock,
ClutterTimeline *timeline)
{
gboolean is_first;
if (g_slist_find (master_clock->timelines, timeline))
return;
is_first = master_clock->timelines == NULL;
master_clock->timelines = g_slist_prepend (master_clock->timelines,
timeline);
if (is_first)
_clutter_master_clock_start_running (master_clock);
}
/*
* _clutter_master_clock_remove_timeline:
* @master_clock: a #ClutterMasterClock
* @timeline: a #ClutterTimeline
*
* Removes @timeline from the list of playing timelines held by the
* master clock.
*/
void
_clutter_master_clock_remove_timeline (ClutterMasterClock *master_clock,
ClutterTimeline *timeline)
{
master_clock->timelines = g_slist_remove (master_clock->timelines,
timeline);
}
/*
* _clutter_master_clock_start_running:
* @master_clock: a #ClutterMasterClock
*
* Called when we have events or redraws to process; if the clock
* is stopped, does the processing necessary to wake it up again.
*/
void
_clutter_master_clock_start_running (ClutterMasterClock *master_clock)
{
/* If called from a different thread, we need to wake up the
* main loop to start running the timelines
*/
g_main_context_wakeup (NULL);
}
/*
* _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_stage_do_update() to
* make sure that all the timelines are advanced and the scene is updated.
*/
void
_clutter_master_clock_advance (ClutterMasterClock *master_clock)
{
GSList *timelines, *l;
CLUTTER_STATIC_TIMER (master_timeline_advance,
"Master Clock",
"Timelines Advancement",
"The time spent advancing all timelines",
0);
g_return_if_fail (CLUTTER_IS_MASTER_CLOCK (master_clock));
CLUTTER_TIMER_START (_clutter_uprof_context, master_timeline_advance);
/* we protect ourselves from timelines being removed during
* the advancement by other timelines by copying the list of
* timelines, taking a reference on them, iterating over the
* copied list and then releasing the reference.
*
* we cannot simply take a reference on the timelines and still
* use the list held by the master clock because the do_tick()
* might result in the creation of a new timeline, which gets
* added at the end of the list with no reference increase and
* thus gets disposed at the end of the iteration.
*
* this implies that a newly added timeline will not be advanced
* by this clock iteration, which is perfectly fine since we're
* in its first cycle.
*
* we also cannot steal the master clock timelines list because
* a timeline might be removed as the direct result of do_tick()
* and remove_timeline() would not find the timeline, failing
* and leaving a dangling pointer behind.
*/
timelines = g_slist_copy (master_clock->timelines);
g_slist_foreach (timelines, (GFunc) g_object_ref, NULL);
for (l = timelines; l != NULL; l = l->next)
_clutter_timeline_do_tick (l->data, master_clock->cur_tick / 1000);
g_slist_foreach (timelines, (GFunc) g_object_unref, NULL);
g_slist_free (timelines);
CLUTTER_TIMER_STOP (_clutter_uprof_context, master_timeline_advance);
}
/**
* _clutter_master_clock_ensure_next_iteration:
* @master_clock: a #ClutterMasterClock
*
* Ensures that the master clock will run at least one iteration
*/
void
_clutter_master_clock_ensure_next_iteration (ClutterMasterClock *master_clock)
{
g_return_if_fail (CLUTTER_IS_MASTER_CLOCK (master_clock));
master_clock->ensure_next_iteration = TRUE;
}