[mutter] compositor: Add a new window group for override-redirect windows

[Jasper St. Pierre <jstpierre src gnome org>]

commit 6b5cf2eb6123a7faf148f0d075408545850936bb
Author: Gayan Perera <gayanper gmail com>
Date:   Thu Dec 27 18:34:12 2012 +0530

    compositor: Add a new window group for override-redirect windows
    
    Put override redirect windows such as menus into a separate window group
    stacked above everything else. This will allow us to visually put these
    above other compositior chrome.
    
    Based on a patch from Muffin.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=633620

 src/compositor/compositor-private.h |    2 +-
 src/compositor/compositor.c         |   19 +++++++++++++++++++
 src/compositor/meta-window-actor.c  |   11 +++++++++--
 src/meta/compositor-mutter.h        |    1 +
 4 files changed, 30 insertions(+), 3 deletions(-)
---
diff --git a/src/compositor/compositor-private.h b/src/compositor/compositor-private.h
index 0176d10..acb8d3c 100644
--- a/src/compositor/compositor-private.h
+++ b/src/compositor/compositor-private.h
@@ -38,7 +38,7 @@ struct _MetaCompScreen
 {
   MetaScreen            *screen;
 
-  ClutterActor          *stage, *window_group, *overlay_group;
+  ClutterActor          *stage, *window_group, *top_window_group, *overlay_group;
   ClutterActor          *background_actor;
   GList                 *windows;
   GHashTable            *windows_by_xid;
diff --git a/src/compositor/compositor.c b/src/compositor/compositor.c
index 3cc6c9c..91b0767 100644
--- a/src/compositor/compositor.c
+++ b/src/compositor/compositor.c
@@ -238,6 +238,23 @@ meta_get_window_group_for_screen (MetaScreen *screen)
 }
 
 /**
+ * meta_get_top_window_group_for_screen:
+ * @screen: a #MetaScreen
+ *
+ * Returns: (transfer none): The top window group corresponding to @screen
+ */
+ClutterActor *
+meta_get_top_window_group_for_screen (MetaScreen *screen)
+{
+  MetaCompScreen *info = meta_screen_get_compositor_data (screen);
+
+  if (!info)
+    return NULL;
+
+  return info->top_window_group;
+}
+
+/**
  * meta_get_background_actor_for_screen:
  * @screen: a #MetaScreen
  *
@@ -588,6 +605,7 @@ meta_compositor_manage_screen (MetaCompositor *compositor,
   }
 
   info->window_group = meta_window_group_new (screen);
+  info->top_window_group = meta_window_group_new (screen);
   info->background_actor = meta_background_actor_new_for_screen (screen);
   info->overlay_group = clutter_group_new ();
 
@@ -597,6 +615,7 @@ meta_compositor_manage_screen (MetaCompositor *compositor,
 
   clutter_container_add (CLUTTER_CONTAINER (info->stage),
                          info->window_group,
+                         info->top_window_group,
                          info->overlay_group,
                          NULL);
 
diff --git a/src/compositor/meta-window-actor.c b/src/compositor/meta-window-actor.c
index f28452e..9980fe6 100644
--- a/src/compositor/meta-window-actor.c
+++ b/src/compositor/meta-window-actor.c
@@ -1524,6 +1524,7 @@ meta_window_actor_new (MetaWindow *window)
   MetaWindowActorPrivate *priv;
   MetaFrame             *frame;
   Window                 top_window;
+  ClutterActor           *window_group;
 
   frame = meta_window_get_frame (window);
   if (frame)
@@ -1556,8 +1557,14 @@ meta_window_actor_new (MetaWindow *window)
   /* Hang our compositor window state off the MetaWindow for fast retrieval */
   meta_window_set_compositor_private (window, G_OBJECT (self));
 
-  clutter_container_add_actor (CLUTTER_CONTAINER (info->window_group),
-                              CLUTTER_ACTOR (self));
+  if (window->layer == META_LAYER_OVERRIDE_REDIRECT)
+    window_group = info->top_window_group;
+  else
+    window_group = info->window_group;
+
+  clutter_container_add_actor (CLUTTER_CONTAINER (window_group),
+                               CLUTTER_ACTOR (self));
+
   clutter_actor_hide (CLUTTER_ACTOR (self));
 
   /* Initial position in the stack is arbitrary; stacking will be synced
diff --git a/src/meta/compositor-mutter.h b/src/meta/compositor-mutter.h
index e196c65..161cfad 100644
--- a/src/meta/compositor-mutter.h
+++ b/src/meta/compositor-mutter.h
@@ -39,6 +39,7 @@ ClutterActor *meta_get_overlay_group_for_screen (MetaScreen *screen);
 Window        meta_get_overlay_window           (MetaScreen *screen);
 GList        *meta_get_window_actors            (MetaScreen *screen);
 ClutterActor *meta_get_window_group_for_screen  (MetaScreen *screen);
+ClutterActor *meta_get_top_window_group_for_screen (MetaScreen *screen);
 
 void        meta_disable_unredirect_for_screen  (MetaScreen *screen);
 void        meta_enable_unredirect_for_screen   (MetaScreen *screen);