mutter/clutter/cogl/clutter-stage-cogl.h
Chris Wilson 239280f855 stage-cogl: Fix damage tracking with varying buffer ages
With server-side buffer allocation, buffers may be returned out of order
(e.g. they may be held onto by external references or hardware). As such
we may see older buffers the frame after we discard the history from
seeing a very young buffer. To overcome this we want to keep the history
in a ring so we can keep track of older entries without keeping an
unbounded list. After converting to a ring, the maximum buffer age
observed during testing was 5 (expected value of 4), but before we could
see ages as high as 9 due to the huge latency spikes caused by doing full
buffer redraws (compounded by external listeners doing readback on the
damaged areas, for example vnc, drm/udl, prime). For this reason, a
maximum age of 16 was chosen to be suitably large enough to prevent these
worst cases from taxing the system.

v2: Fix off-by-one in combining the damage histroy into the clipping
rectangle, and apply copious whitespace fixes.

Bugzilla: https://bugzilla.gnome.org/show_bug.cgi?id=745512
References: https://bugzilla.gnome.org/show_bug.cgi?id=724788
References: https://bugzilla.gnome.org/show_bug.cgi?id=669122
2015-03-15 14:46:42 +00:00

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2.3 KiB
C

#ifndef __CLUTTER_STAGE_COGL_H__
#define __CLUTTER_STAGE_COGL_H__
#include <cairo.h>
#include <clutter/clutter-backend.h>
#include <clutter/clutter-stage.h>
#ifdef COGL_HAS_X11_SUPPORT
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <X11/Xutil.h>
#endif
G_BEGIN_DECLS
#define CLUTTER_TYPE_STAGE_COGL (_clutter_stage_cogl_get_type ())
#define CLUTTER_STAGE_COGL(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), CLUTTER_TYPE_STAGE_COGL, ClutterStageCogl))
#define CLUTTER_IS_STAGE_COGL(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), CLUTTER_TYPE_STAGE_COGL))
#define CLUTTER_STAGE_COGL_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), CLUTTER_TYPE_STAGE_COGL, ClutterStageCoglClass))
#define CLUTTER_IS_STAGE_COGL_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), CLUTTER_TYPE_STAGE_COGL))
#define CLUTTER_STAGE_COGL_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), CLUTTER_TYPE_STAGE_COGL, ClutterStageCoglClass))
typedef struct _ClutterStageCogl ClutterStageCogl;
typedef struct _ClutterStageCoglClass ClutterStageCoglClass;
struct _ClutterStageCogl
{
GObject parent_instance;
/* the stage wrapper */
ClutterStage *wrapper;
/* back pointer to the backend */
ClutterBackend *backend;
CoglOnscreen *onscreen;
gint64 last_presentation_time;
float refresh_rate;
gint64 update_time;
gint pending_swaps;
CoglFrameClosure *frame_closure;
/* We only enable clipped redraws after 2 frames, since we've seen
* a lot of drivers can struggle to get going and may output some
* junk frames to start with. */
unsigned long frame_count;
cairo_rectangle_int_t bounding_redraw_clip;
guint initialized_redraw_clip : 1;
/* TRUE if the current paint cycle has a clipped redraw. In that
case bounding_redraw_clip specifies the the bounds. */
guint using_clipped_redraw : 1;
guint dirty_backbuffer : 1;
/* Stores a list of previous damaged areas */
#define DAMAGE_HISTORY_MAX 16
#define DAMAGE_HISTORY(x) ((x) & (DAMAGE_HISTORY_MAX - 1))
cairo_rectangle_int_t damage_history[DAMAGE_HISTORY_MAX];
unsigned damage_index;
};
struct _ClutterStageCoglClass
{
GObjectClass parent_class;
};
GType _clutter_stage_cogl_get_type (void) G_GNUC_CONST;
G_END_DECLS
#endif /* __CLUTTER_STAGE_COGL_H__ */