[mutter] clutter/actor: Use priv->parent instead of public API sometimes

[Jonas Ådahl <jadahl src gnome org>]

commit a7bf6322e30626bc93c62743dece5711b1ca6ccb
Author: Jonas Dreßler <verdre v0yd nl>
Date:   Fri Mar 20 17:39:35 2020 +0100

    clutter/actor: Use priv->parent instead of public API sometimes
    
    The public API to get the parent actor, clutter_actor_get_parent() does
    a type check whether the actor is actually a ClutterActor. In case of
    _clutter_actor_apply_relative_transformation_matrix(), which is called
    recursively and very often during the paint process, this type check
    shows up with almost twice the amount of hits than the actual matrix
    multiplication.
    
    So use the parent pointer directly in some code paths that are executed
    very often and avoid the expensive type checking there, we can do that
    since both places are not public API.
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1259

 clutter/clutter/clutter-actor.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)
---
diff --git a/clutter/clutter/clutter-actor.c b/clutter/clutter/clutter-actor.c
index aa152977b..d18028285 100644
--- a/clutter/clutter/clutter-actor.c
+++ b/clutter/clutter/clutter-actor.c
@@ -2792,7 +2792,7 @@ _clutter_actor_propagate_queue_redraw (ClutterActor       *self,
       if (stop)
         break;
 
-      self = clutter_actor_get_parent (self);
+      self = self->priv->parent;
     }
 }
 
@@ -3310,8 +3310,6 @@ _clutter_actor_apply_relative_transformation_matrix (ClutterActor *self,
                                                      ClutterActor *ancestor,
                                                      CoglMatrix *matrix)
 {
-  ClutterActor *parent;
-
   /* Note we terminate before ever calling stage->apply_transform()
    * since that would conceptually be relative to the underlying
    * window OpenGL coordinates so we'd need a special @ancestor
@@ -3319,10 +3317,9 @@ _clutter_actor_apply_relative_transformation_matrix (ClutterActor *self,
   if (self == ancestor)
     return;
 
-  parent = clutter_actor_get_parent (self);
-
-  if (parent != NULL)
-    _clutter_actor_apply_relative_transformation_matrix (parent, ancestor,
+  if (self->priv->parent != NULL)
+    _clutter_actor_apply_relative_transformation_matrix (self->priv->parent,
+                                                         ancestor,
                                                          matrix);
 
   _clutter_actor_apply_modelview_transform (self, matrix);