window-actor: Rebuild the shape and mask when the surface updates

Connecting to size-changed is wrong -- size-changed tells us when
we *told* the X server or resize the window. For X11, we're sort of
guaranteed that the surface will be updated at some point before the
next frame, but for Xwayland, we can't be sure that the new surface is
attached at this point.

This fixes weird artifacts when resizing apps like xclock.

src/compositor/meta-shaped-texture.c

@@ -65,6 +65,14 @@ G_DEFINE_TYPE_WITH_CODE (MetaShapedTexture, meta_shaped_texture, CLUTTER_TYPE_AC
   (G_TYPE_INSTANCE_GET_PRIVATE ((obj), META_TYPE_SHAPED_TEXTURE, \
                                 MetaShapedTexturePrivate))
 
+enum {
+  SIZE_CHANGED,
+
+  LAST_SIGNAL,
+};
+
+static guint signals[LAST_SIGNAL];
+
 struct _MetaShapedTexturePrivate
 {
   MetaTextureTower *paint_tower;
@@ -97,6 +105,13 @@ meta_shaped_texture_class_init (MetaShapedTextureClass *klass)
   actor_class->paint = meta_shaped_texture_paint;
   actor_class->get_paint_volume = meta_shaped_texture_get_paint_volume;
 
+  signals[SIZE_CHANGED] = g_signal_new ("size-changed",
+                                        G_TYPE_FROM_CLASS (gobject_class),
+                                        G_SIGNAL_RUN_LAST,
+                                        0,
+                                        NULL, NULL, NULL,
+                                        G_TYPE_NONE, 0);
+
   g_type_class_add_private (klass, sizeof (MetaShapedTexturePrivate));
 }
 
@@ -262,6 +277,7 @@ set_cogl_texture (MetaShapedTexture *stex,
       priv->tex_width = width;
       priv->tex_height = height;
       clutter_actor_queue_relayout (CLUTTER_ACTOR (stex));
+      g_signal_emit (stex, signals[SIZE_CHANGED], 0);
     }
 
   /* NB: We don't queue a redraw of the actor here because we don't

src/compositor/meta-surface-actor.c

@@ -36,6 +36,7 @@ G_DEFINE_ABSTRACT_TYPE_WITH_CODE (MetaSurfaceActor, meta_surface_actor, CLUTTER_
 
 enum {
   REPAINT_SCHEDULED,
+  SIZE_CHANGED,
 
   LAST_SIGNAL,
 };
@@ -120,6 +121,13 @@ meta_surface_actor_class_init (MetaSurfaceActorClass *klass)
                                              NULL, NULL, NULL,
                                              G_TYPE_NONE, 0);
 
+  signals[SIZE_CHANGED] = g_signal_new ("size-changed",
+                                        G_TYPE_FROM_CLASS (object_class),
+                                        G_SIGNAL_RUN_LAST,
+                                        0,
+                                        NULL, NULL, NULL,
+                                        G_TYPE_NONE, 0);
+
   g_type_class_add_private (klass, sizeof (MetaSurfaceActorPrivate));
 }
 
@@ -144,6 +152,14 @@ cullable_iface_init (MetaCullableInterface *iface)
   iface->reset_culling = meta_surface_actor_reset_culling;
 }
 
+static void
+texture_size_changed (MetaShapedTexture *texture,
+                      gpointer           user_data)
+{
+  MetaSurfaceActor *actor = META_SURFACE_ACTOR (user_data);
+  g_signal_emit (actor, signals[SIZE_CHANGED], 0);
+}
+
 static void
 meta_surface_actor_init (MetaSurfaceActor *self)
 {
@@ -154,6 +170,8 @@ meta_surface_actor_init (MetaSurfaceActor *self)
                                                    MetaSurfaceActorPrivate);
 
   priv->texture = META_SHAPED_TEXTURE (meta_shaped_texture_new ());
+  g_signal_connect_object (priv->texture, "size-changed",
+                           G_CALLBACK (texture_size_changed), self, 0);
   clutter_actor_add_child (CLUTTER_ACTOR (self), CLUTTER_ACTOR (priv->texture));
 }
 

src/compositor/meta-window-actor.c

@@ -76,6 +76,7 @@ struct _MetaWindowActorPrivate
   gint64            frame_drawn_time;
 
   guint             repaint_scheduled_id;
+  guint             size_changed_id;
 
   /*
    * These need to be counters rather than flags, since more plugins
@@ -272,10 +273,10 @@ window_appears_focused_notify (MetaWindow *mw,
 }
 
 static void
-window_size_changed (MetaWindow *mw,
+surface_size_changed (MetaSurfaceActor *actor,
-                     gpointer    data)
+                      gpointer          user_data)
 {
-  MetaWindowActor *self = META_WINDOW_ACTOR (data);
+  MetaWindowActor *self = META_WINDOW_ACTOR (user_data);
 
   meta_window_actor_update_shape (self);
 }
@@ -368,6 +369,7 @@ set_surface (MetaWindowActor  *self,
   if (priv->surface)
     {
       g_signal_handler_disconnect (priv->surface, priv->repaint_scheduled_id);
+      g_signal_handler_disconnect (priv->surface, priv->size_changed_id);
       priv->repaint_scheduled_id = 0;
       clutter_actor_remove_child (CLUTTER_ACTOR (self), CLUTTER_ACTOR (priv->surface));
       g_object_unref (priv->surface);
@@ -380,6 +382,8 @@ set_surface (MetaWindowActor  *self,
       g_object_ref_sink (priv->surface);
       priv->repaint_scheduled_id = g_signal_connect (priv->surface, "repaint-scheduled",
                                                      G_CALLBACK (surface_repaint_scheduled), self);
+      priv->size_changed_id = g_signal_connect (priv->surface, "size-changed",
+                                                G_CALLBACK (surface_size_changed), self);
       clutter_actor_add_child (CLUTTER_ACTOR (self), CLUTTER_ACTOR (priv->surface));
 
       /* If the previous surface actor was frozen, start out
@@ -489,8 +493,6 @@ meta_window_actor_set_property (GObject      *object,
       priv->window = g_value_dup_object (value);
       g_signal_connect_object (priv->window, "notify::appears-focused",
                                G_CALLBACK (window_appears_focused_notify), self, 0);
-      g_signal_connect_object (priv->window, "size-changed",
-                               G_CALLBACK (window_size_changed), self, 0);
       break;
     case PROP_NO_SHADOW:
       {