From 890b29a57cb1776738dbcada4842182b882a46fd Mon Sep 17 00:00:00 2001
From: Robert Bragg <robert@linux.intel.com>
Date: Wed, 20 Oct 2010 18:26:01 +0100
Subject: [PATCH] actor: re-work unrealize to work with composite actors

Unrealizing an actor is a recursive process that needs to traverse the
children of an actor to ensure they are also unrealized. This maintains
the invariant that if any given actor is marked as unrealized then you
know that all its children have also been unrealized.

The previous implementation would use the container interface's
foreach_with_internals vfunc to explicitly traverse the children of
container actors but this didn't consider composite actors that aren't
containers.

Since clutter-actor now maintains an explicit list of children we can
also handle composite actors that aren't containers using
_clutter_actor_traverse.
---
 clutter/clutter-actor.c |   57 +++++++++++++++++++++++++++-------------------
 1 files changed, 33 insertions(+), 24 deletions(-)

diff --git a/clutter/clutter-actor.c b/clutter/clutter-actor.c
index 070323e..f1da940 100644
--- a/clutter/clutter-actor.c
+++ b/clutter/clutter-actor.c
@@ -1408,11 +1408,6 @@ clutter_actor_real_unrealize (ClutterActor *self)
 {
   /* we must be unmapped (implying our children are also unmapped) */
   g_assert (!CLUTTER_ACTOR_IS_MAPPED (self));
-
-  if (CLUTTER_IS_CONTAINER (self))
-    clutter_container_foreach_with_internals (CLUTTER_CONTAINER (self),
-                                              CLUTTER_CALLBACK (clutter_actor_unrealize_not_hiding),
-                                              NULL);
 }

 /**
@@ -1466,6 +1461,34 @@ clutter_actor_unrealize (ClutterActor *self)
   clutter_actor_unrealize_not_hiding (self);
 }

+static ClutterActorTraverseVisitFlags
+unrealize_actor_before_children_cb (ClutterActor *self,
+                                    int depth,
+                                    void *user_data)
+{
+  /* If an actor is already unrealized we know its children have also
+   * already been unrealized... */
+  if (!CLUTTER_ACTOR_IS_REALIZED (self))
+    return CLUTTER_ACTOR_TRAVERSE_VISIT_SKIP_CHILDREN;
+
+  g_signal_emit (self, actor_signals[UNREALIZE], 0);
+
+  return CLUTTER_ACTOR_TRAVERSE_VISIT_CONTINUE;
+}
+
+static ClutterActorTraverseVisitFlags
+unrealize_actor_after_children_cb (ClutterActor *self,
+                                   int depth,
+                                   void *user_data)
+{
+  /* We want to unset the realized flag only _after_
+   * child actors are unrealized, to maintain invariants.
+   */
+  CLUTTER_ACTOR_UNSET_FLAGS (self, CLUTTER_ACTOR_REALIZED);
+  _clutter_notify_by_pspec (G_OBJECT (self), obj_props[PROP_REALIZED]);
+  return CLUTTER_ACTOR_TRAVERSE_VISIT_CONTINUE;
+}
+
 /*
  * clutter_actor_unrealize_not_hiding:
  * @self: A #ClutterActor
@@ -1493,25 +1516,11 @@ clutter_actor_unrealize (ClutterActor *self)
 static void
 clutter_actor_unrealize_not_hiding (ClutterActor *self)
 {
-  /* All callers of clutter_actor_unrealize_not_hiding() should have
-   * taken care of unmapping the actor first. This means
-   * all our children should also be unmapped.
-   */
-  g_assert (!CLUTTER_ACTOR_IS_MAPPED (self));
-
-  if (!CLUTTER_ACTOR_IS_REALIZED (self))
-    return;
-
-  /* The default handler for the signal should recursively unrealize
-   * child actors. We want to unset the realized flag only _after_
-   * child actors are unrealized, to maintain invariants.
-   */
-
-  g_signal_emit (self, actor_signals[UNREALIZE], 0);
-
-  CLUTTER_ACTOR_UNSET_FLAGS (self, CLUTTER_ACTOR_REALIZED);
-
-  _clutter_notify_by_pspec (G_OBJECT (self), obj_props[PROP_REALIZED]);
+  _clutter_actor_traverse (self,
+                           CLUTTER_ACTOR_TRAVERSE_DEPTH_FIRST,
+                           unrealize_actor_before_children_cb,
+                           unrealize_actor_after_children_cb,
+                           NULL);
 }

 /*
--
1.7.0.4