[clutter] actor: use paint opacity to paint the background color

[Emmanuele Bassi <ebassi src gnome org>]

commit 75549456fd7697bf8ad1e5aaa1776b87554bcc37
Author: Emmanuele Bassi <ebassi linux intel com>
Date:   Tue Jan 24 14:52:33 2012 +0000

    actor: use paint opacity to paint the background color

 clutter/clutter-actor.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/clutter/clutter-actor.c b/clutter/clutter-actor.c
index c98b8be..b11e562 100644
--- a/clutter/clutter-actor.c
+++ b/clutter/clutter-actor.c
@@ -677,6 +677,8 @@ static void _clutter_actor_get_relative_transformation_matrix (ClutterActor *sel
 
 static ClutterPaintVolume *_clutter_actor_get_paint_volume_mutable (ClutterActor *self);
 
+static guint8   clutter_actor_get_paint_opacity_internal        (ClutterActor *self);
+
 static void on_layout_manager_changed (ClutterLayoutManager *manager,
                                        ClutterActor         *self);
 
@@ -2997,13 +2999,18 @@ clutter_actor_real_paint (ClutterActor *actor)
   if (priv->bg_color_set)
     {
       float width, height;
+      guint8 real_alpha;
 
       clutter_actor_box_get_size (&priv->allocation, &width, &height);
 
+      real_alpha = clutter_actor_get_paint_opacity_internal (actor)
+                 * priv->bg_color.alpha
+                 / 255;
+
       cogl_set_source_color4ub (priv->bg_color.red,
                                 priv->bg_color.green,
                                 priv->bg_color.blue,
-                                priv->bg_color.alpha);
+                                real_alpha);
 
       cogl_rectangle (0, 0, width, height);
     }