diff options
| -rw-r--r-- | gdk/gdkframeclockidle.c | 34 |
1 files changed, 14 insertions, 20 deletions
diff --git a/gdk/gdkframeclockidle.c b/gdk/gdkframeclockidle.c index 4884a81fb9..ec66950b70 100644 --- a/gdk/gdkframeclockidle.c +++ b/gdk/gdkframeclockidle.c @@ -140,6 +140,7 @@ gdk_frame_clock_idle_init (GdkFrameClockIdle *frame_clock_idle) gdk_frame_clock_idle_get_instance_private (frame_clock_idle); priv->freeze_count = 0; + priv->smoothed_frame_time_period = FRAME_INTERVAL; } static void @@ -346,23 +347,6 @@ maybe_stop_idle (GdkFrameClockIdle *clock_idle) } } -static gint64 -compute_min_next_frame_time (GdkFrameClockIdle *clock_idle, - gint64 last_frame_time) -{ - gint64 presentation_time; - gint64 refresh_interval; - - gdk_frame_clock_get_refresh_info (GDK_FRAME_CLOCK (clock_idle), - last_frame_time, - &refresh_interval, &presentation_time); - - if (presentation_time == 0) - return last_frame_time + refresh_interval; - else - return presentation_time + refresh_interval / 2; -} - static gboolean gdk_frame_clock_flush_idle (void *data) { @@ -656,9 +640,19 @@ gdk_frame_clock_paint_idle (void *data) */ if (priv->freeze_count == 0) { - priv->min_next_frame_time = compute_min_next_frame_time (clock_idle, - priv->smoothed_frame_time_base - - priv->smoothed_frame_time_phase); + /* + * If we don't receive "frame drawn" events, smooth_cycle_start will simply be advanced in constant increments of + * the refresh interval. That way we get absolute target times for the next cycles, which should prevent skewing + * in the scheduling of the frame clock. + * + * Once we do receive "frame drawn" events, smooth_cycle_start will track the vsync, and do so in a more stable + * way compared to frame_time. If we then no longer receive "frame drawn" events, smooth_cycle_start will again be + * simply advanced in increments of the refresh interval, but this time we are in sync with the vsync. If we start + * receiving "frame drawn" events shortly after loosing them, then we should still be in sync. + */ + gint64 smooth_cycle_start = priv->smoothed_frame_time_base - priv->smoothed_frame_time_phase; + priv->min_next_frame_time = smooth_cycle_start + priv->smoothed_frame_time_period; + maybe_start_idle (clock_idle, FALSE); } |