[gnome-shell] Use the new "background actor" functionality in Mutter

[Owen Taylor <otaylor src gnome org>]

commit e5a802bf99d3487dab2deb2c7750750648573365
Author: Owen W. Taylor <otaylor fishsoup net>
Date:   Sun Nov 14 13:13:44 2010 -0500

    Use the new "background actor" functionality in Mutter
    
    The code to draw the root background has now been moved into Mutter,
    with added smarts to not draw obscured portions. Remove the old
    version of the code and clone the Mutter background actor to draw
    the background in the overview.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=634836

 js/ui/main.js      |   10 +---
 js/ui/workspace.js |    2 +-
 src/shell-global.c |  157 ++++------------------------------------------------
 src/shell-global.h |    2 -
 4 files changed, 14 insertions(+), 157 deletions(-)
---
diff --git a/js/ui/main.js b/js/ui/main.js
index 4589ad0..82172cf 100644
--- a/js/ui/main.js
+++ b/js/ui/main.js
@@ -98,8 +98,8 @@ function start() {
     Shell.AppUsage.get_default();
 
     // The stage is always covered so Clutter doesn't need to clear it; however
-    // the color is used as the default contents for the actor created by
-    // global.create_root_pixmap_actor() so we set it anyways.
+    // the color is used as the default contents for the Mutter root background
+    // actor so set it anyways.
     global.stage.color = DEFAULT_BACKGROUND_COLOR;
     global.stage.no_clear_hint = true;
 
@@ -162,10 +162,6 @@ function start() {
         }
     });
 
-    background = global.create_root_pixmap_actor();
-    global.stage.add_actor(background);
-    background.lower_bottom();
-
     global.gdk_screen.connect('monitors-changed', _relayout);
 
     ExtensionSystem.init();
@@ -241,8 +237,6 @@ function _relayout() {
     panel.actor.set_size(primary.width, Panel.PANEL_HEIGHT);
     overview.relayout();
 
-    background.set_size(global.screen_width, global.screen_height);
-
     // To avoid updating the position and size of the workspaces
     // in the overview, we just hide the overview. The positions
     // will be updated when it is next shown. We do the same for
diff --git a/js/ui/workspace.js b/js/ui/workspace.js
index c4a225c..349c87b 100644
--- a/js/ui/workspace.js
+++ b/js/ui/workspace.js
@@ -301,7 +301,7 @@ DesktopClone.prototype = {
     _init : function(window) {
         this.actor = new Clutter.Group({ reactive: true });
 
-        let background = new Clutter.Clone({ source: Main.background.source });
+        let background = new Clutter.Clone({ source: global.background_actor });
         this.actor.add_actor(background);
 
         if (window) {
diff --git a/src/shell-global.c b/src/shell-global.c
index 40fa490..dad0b20 100644
--- a/src/shell-global.c
+++ b/src/shell-global.c
@@ -35,7 +35,6 @@
 #define MAGNIFIER_DBUS_SERVICE "org.gnome.Magnifier"
 
 static void grab_notify (GtkWidget *widget, gboolean is_grab, gpointer user_data);
-static void update_root_window_pixmap (ShellGlobal *global);
 
 struct _ShellGlobal {
   GObject parent;
@@ -86,6 +85,7 @@ enum {
   PROP_STAGE,
   PROP_STAGE_INPUT_MODE,
   PROP_WINDOW_GROUP,
+  PROP_BACKGROUND_ACTOR,
   PROP_WINDOW_MANAGER,
   PROP_SETTINGS,
   PROP_DATADIR,
@@ -160,6 +160,9 @@ shell_global_get_property(GObject         *object,
     case PROP_WINDOW_GROUP:
       g_value_set_object (value, meta_plugin_get_window_group (global->plugin));
       break;
+    case PROP_BACKGROUND_ACTOR:
+      g_value_set_object (value, meta_plugin_get_background_actor (global->plugin));
+      break;
     case PROP_WINDOW_MANAGER:
       g_value_set_object (value, global->wm);
       break;
@@ -299,6 +302,13 @@ shell_global_class_init (ShellGlobalClass *klass)
                                                         CLUTTER_TYPE_ACTOR,
                                                         G_PARAM_READABLE));
   g_object_class_install_property (gobject_class,
+                                   PROP_BACKGROUND_ACTOR,
+                                   g_param_spec_object ("background-actor",
+                                                        "Background Actor",
+                                                        "Actor drawing root window background",
+                                                        CLUTTER_TYPE_ACTOR,
+                                                        G_PARAM_READABLE));
+  g_object_class_install_property (gobject_class,
                                    PROP_WINDOW_MANAGER,
                                    g_param_spec_object ("window-manager",
                                                         "Window Manager",
@@ -1122,77 +1132,6 @@ grab_notify (GtkWidget *widget, gboolean was_grabbed, gpointer user_data)
   shell_global_set_stage_input_mode (global, global->input_mode);
 }
 
-/*
- * Updates the global->root_pixmap actor with the root window's pixmap or fails
- * with a warning.
- */
-static void
-update_root_window_pixmap (ShellGlobal *global)
-{
-  Atom type;
-  int format;
-  gulong nitems;
-  gulong bytes_after;
-  guchar *data;
-  Pixmap root_pixmap_id = None;
-
-  if (!XGetWindowProperty (gdk_x11_get_default_xdisplay (),
-                           gdk_x11_get_default_root_xwindow (),
-                           gdk_x11_get_xatom_by_name ("_XROOTPMAP_ID"),
-                           0, LONG_MAX,
-                           False,
-                           AnyPropertyType,
-                           &type, &format, &nitems, &bytes_after, &data) &&
-      type != None)
-  {
-     /* Got a property. */
-     if (type == XA_PIXMAP && format == 32 && nitems == 1)
-       {
-         /* Was what we expected. */
-         root_pixmap_id = *(Pixmap *)data;
-       }
-     else
-       {
-         g_warning ("Could not get the root window pixmap");
-       }
-
-     XFree(data);
-  }
-
-  clutter_x11_texture_pixmap_set_pixmap (CLUTTER_X11_TEXTURE_PIXMAP (global->root_pixmap),
-                                         root_pixmap_id);
-}
-
-/*
- * Called when the X server emits a root window change event. If the event is
- * about a new pixmap, update the global->root_pixmap actor.
- */
-static GdkFilterReturn
-root_window_filter (GdkXEvent *native, GdkEvent *event, gpointer data)
-{
-  XEvent *xevent = (XEvent *)native;
-
-  if ((xevent->type == PropertyNotify) &&
-      (xevent->xproperty.window == gdk_x11_get_default_root_xwindow ()) &&
-      (xevent->xproperty.atom == gdk_x11_get_xatom_by_name ("_XROOTPMAP_ID")))
-    update_root_window_pixmap (SHELL_GLOBAL (data));
-
-  return GDK_FILTER_CONTINUE;
-}
-
-/*
- * Called when the root window pixmap actor is destroyed.
- */
-static void
-root_pixmap_destroy (GObject *sender, gpointer data)
-{
-  ShellGlobal *global = SHELL_GLOBAL (data);
-
-  gdk_window_remove_filter (gdk_get_default_root_window (),
-                            root_window_filter, global);
-  global->root_pixmap = NULL;
-}
-
 /**
  * shell_global_format_time_relative_pretty:
  * @global:
@@ -1242,80 +1181,6 @@ shell_global_format_time_relative_pretty (ShellGlobal *global,
 }
 
 /**
- * shell_global_create_root_pixmap_actor:
- * @global: a #ShellGlobal
- *
- * Creates an actor showing the root window pixmap.
- *
- * Return value: (transfer none): a #ClutterActor with the root window pixmap.
- *               The actor is floating, hence (transfer none).
- */
-ClutterActor *
-shell_global_create_root_pixmap_actor (ShellGlobal *global)
-{
-  GdkWindow *window;
-  ClutterActor *stage;
-  ClutterColor stage_color;
-
-  /* The actor created is actually a ClutterClone of global->root_pixmap. */
-
-  if (global->root_pixmap == NULL)
-    {
-      global->root_pixmap = clutter_glx_texture_pixmap_new ();
-
-      clutter_actor_set_size (CLUTTER_ACTOR (global->root_pixmap),
-                              global->last_change_screen_width,
-                              global->last_change_screen_height);
-
-      clutter_texture_set_repeat (CLUTTER_TEXTURE (global->root_pixmap),
-                                  TRUE, TRUE);
-
-      /* The low and medium quality filters give nearest-neighbor resizing. */
-      clutter_texture_set_filter_quality (CLUTTER_TEXTURE (global->root_pixmap),
-                                          CLUTTER_TEXTURE_QUALITY_HIGH);
-
-      /* Initialize to the stage color, since that's what will be seen
-       * in the main view if there's no actual background window.
-       */
-      stage = meta_plugin_get_stage (global->plugin);
-      clutter_stage_get_color (CLUTTER_STAGE (stage), &stage_color);
-      clutter_texture_set_from_rgb_data (CLUTTER_TEXTURE (global->root_pixmap),
-                                         /* ClutterColor has the same layout
-                                          * as one pixel of RGB(A) data.
-                                          */
-                                         (const guchar *)&stage_color, FALSE,
-                                         /* w, h, rowstride, bpp, flags */
-                                         1, 1, 3, 3, 0, NULL);
-
-      /* We can only clone an actor within a stage, so we hide the source
-       * texture then add it to the stage */
-      clutter_actor_hide (global->root_pixmap);
-      clutter_container_add_actor (CLUTTER_CONTAINER (stage),
-                                   global->root_pixmap);
-
-      /* This really should never happen; but just in case... */
-      g_signal_connect (global->root_pixmap, "destroy",
-                        G_CALLBACK (root_pixmap_destroy), global);
-
-      /* Metacity handles changes to some root window properties in its global
-       * event filter, though not _XROOTPMAP_ID. For all root window property
-       * changes, the global filter returns GDK_FILTER_CONTINUE, so our
-       * window specific filter will be called after the global one.
-       *
-       * Because Metacity is already handling root window property updates,
-       * we don't have to worry about adding the PropertyChange mask to the
-       * root window to get PropertyNotify events.
-       */
-      window = gdk_get_default_root_window ();
-      gdk_window_add_filter (window, root_window_filter, global);
-
-      update_root_window_pixmap (global);
-    }
-
-  return clutter_clone_new (global->root_pixmap);
-}
-
-/**
  * shell_global_get_monitors:
  * @global: the #ShellGlobal
  *
diff --git a/src/shell-global.h b/src/shell-global.h
index ab0f50b..b8c5af7 100644
--- a/src/shell-global.h
+++ b/src/shell-global.h
@@ -89,8 +89,6 @@ void shell_global_maybe_gc (ShellGlobal *global);
 
 void shell_global_format_time_relative_pretty (ShellGlobal *global, guint delta, char **text, guint *next_update);
 
-ClutterActor *shell_global_create_root_pixmap_actor (ShellGlobal *global);
-
 GSList       *shell_global_get_monitors        (ShellGlobal  *global);
 MetaRectangle *shell_global_get_primary_monitor (ShellGlobal  *global);
 MetaRectangle *shell_global_get_focus_monitor   (ShellGlobal  *global);