From 07e964e9fc8bb55c412ae1227d13aef2bf74de5e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonas=20=C3=85dahl?= <jadahl@gmail.com>
Date: Wed, 12 Aug 2020 18:08:35 +0200
Subject: [PATCH] clutter/actor: Return the actor used when picking clock

The actor used might be relevant, so that e.g. if it moves or for some
other reason changes stage views, the user can listen for that.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1404
---
 clutter/clutter/clutter-actor.c        | 18 ++++++++++++++----
 clutter/clutter/clutter-mutter.h       |  3 ++-
 clutter/clutter/clutter-timeline.c     |  2 +-
 src/compositor/meta-window-actor-x11.c |  2 +-
 src/tests/stage-view-tests.c           |  6 +++---
 5 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/clutter/clutter/clutter-actor.c b/clutter/clutter/clutter-actor.c
index ab77fa37e..ecdfaf711 100644
--- a/clutter/clutter/clutter-actor.c
+++ b/clutter/clutter/clutter-actor.c
@@ -16356,13 +16356,17 @@ clutter_actor_is_effectively_on_stage_view (ClutterActor     *self,
 /**
  * clutter_actor_pick_frame_clock: (skip)
  * @self: a #ClutterActor
+ * @out_actor: (nullable): a pointer to an #ClutterActor
  *
  * Pick the most suitable frame clock for driving animations for this actor.
  *
+ * The #ClutterActor used for picking the frame clock is written @out_actor.
+ *
  * Returns: (transfer none): a #ClutterFrameClock
  */
 ClutterFrameClock *
-clutter_actor_pick_frame_clock (ClutterActor *self)
+clutter_actor_pick_frame_clock (ClutterActor  *self,
+                                ClutterActor **out_actor)
 {
   ClutterActorPrivate *priv = self->priv;
   float max_refresh_rate = 0.0;
@@ -16372,7 +16376,7 @@ clutter_actor_pick_frame_clock (ClutterActor *self)
   if (!priv->stage_views)
     {
      if (priv->parent)
-       return clutter_actor_pick_frame_clock (priv->parent);
+       return clutter_actor_pick_frame_clock (priv->parent, out_actor);
      else
        return NULL;
     }
@@ -16391,9 +16395,15 @@ clutter_actor_pick_frame_clock (ClutterActor *self)
     }
 
   if (best_view)
-    return clutter_stage_view_get_frame_clock (best_view);
+    {
+      if (out_actor)
+        *out_actor = self;
+      return clutter_stage_view_get_frame_clock (best_view);
+    }
   else
-    return NULL;
+    {
+      return NULL;
+    }
 }
 
 /**
diff --git a/clutter/clutter/clutter-mutter.h b/clutter/clutter/clutter-mutter.h
index 126aabf76..654c6dac0 100644
--- a/clutter/clutter/clutter-mutter.h
+++ b/clutter/clutter/clutter-mutter.h
@@ -69,7 +69,8 @@ CLUTTER_EXPORT
 gboolean clutter_actor_has_transitions (ClutterActor *actor);
 
 CLUTTER_EXPORT
-ClutterFrameClock * clutter_actor_pick_frame_clock (ClutterActor *self);
+ClutterFrameClock * clutter_actor_pick_frame_clock (ClutterActor  *self,
+                                                    ClutterActor **out_actor);
 
 #undef __CLUTTER_H_INSIDE__
 
diff --git a/clutter/clutter/clutter-timeline.c b/clutter/clutter/clutter-timeline.c
index 6750072a1..4a36da435 100644
--- a/clutter/clutter/clutter-timeline.c
+++ b/clutter/clutter/clutter-timeline.c
@@ -393,7 +393,7 @@ update_frame_clock (ClutterTimeline *timeline)
   if (!priv->actor)
     goto out;
 
-  frame_clock = clutter_actor_pick_frame_clock (priv->actor);
+  frame_clock = clutter_actor_pick_frame_clock (priv->actor, NULL);
   if (frame_clock)
     {
       g_clear_signal_handler (&priv->stage_stage_views_handler_id, priv->stage);
diff --git a/src/compositor/meta-window-actor-x11.c b/src/compositor/meta-window-actor-x11.c
index 9ea907b3c..a1b419bbe 100644
--- a/src/compositor/meta-window-actor-x11.c
+++ b/src/compositor/meta-window-actor-x11.c
@@ -1237,7 +1237,7 @@ handle_stage_views_changed (MetaWindowActorX11 *actor_x11)
 {
   ClutterActor *actor = CLUTTER_ACTOR (actor_x11);
 
-  actor_x11->frame_clock = clutter_actor_pick_frame_clock (actor);
+  actor_x11->frame_clock = clutter_actor_pick_frame_clock (actor, NULL);
   if (actor_x11->frame_clock && actor_x11->pending_schedule_update_now)
     {
       clutter_frame_clock_schedule_update_now (actor_x11->frame_clock);
diff --git a/src/tests/stage-view-tests.c b/src/tests/stage-view-tests.c
index f298b8ba8..684319d41 100644
--- a/src/tests/stage-view-tests.c
+++ b/src/tests/stage-view-tests.c
@@ -652,15 +652,15 @@ meta_test_actor_stage_views_frame_clock (void)
                      stage_views->data,
                      stage_views->next->data);
 
-  frame_clock = clutter_actor_pick_frame_clock (actor_1);
+  frame_clock = clutter_actor_pick_frame_clock (actor_1, NULL);
   g_assert_cmpfloat (clutter_frame_clock_get_refresh_rate (frame_clock),
                      ==,
                      60.0);
-  frame_clock = clutter_actor_pick_frame_clock (actor_2);
+  frame_clock = clutter_actor_pick_frame_clock (actor_2, NULL);
   g_assert_cmpfloat (clutter_frame_clock_get_refresh_rate (frame_clock),
                      ==,
                      30.0);
-  frame_clock = clutter_actor_pick_frame_clock (actor_3);
+  frame_clock = clutter_actor_pick_frame_clock (actor_3, NULL);
   g_assert_cmpfloat (clutter_frame_clock_get_refresh_rate (frame_clock),
                      ==,
                      60.0);