window-actor: Add API to update regions

For X11 clients running on Xwayland, the opaque, input and shape regions
are processed from different properties and may occur at a different
time, before the actual buffer is eventually committed by Xwayland.

Add a new API `update_regions` to window actor to trigger the update of
those regions when needed.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1091

src/compositor/meta-window-actor-private.h

@@ -28,6 +28,7 @@ struct _MetaWindowActorClass
   void (*queue_destroy) (MetaWindowActor *actor);
   void (*set_frozen) (MetaWindowActor *actor,
                       gboolean         frozen);
+  void (*update_regions) (MetaWindowActor *actor);
 };
 
 typedef enum
@@ -88,4 +89,6 @@ gboolean meta_window_actor_is_frozen (MetaWindowActor *self);
 
 gboolean meta_window_actor_is_opaque (MetaWindowActor *self);
 
+void meta_window_actor_update_regions (MetaWindowActor *self);
+
 #endif /* META_WINDOW_ACTOR_PRIVATE_H */

src/compositor/meta-window-actor-wayland.c

@@ -162,6 +162,11 @@ meta_window_actor_wayland_get_paint_volume (ClutterActor       *actor,
   return TRUE;
 }
 
+static void
+meta_window_actor_wayland_update_regions (MetaWindowActor *actor)
+{
+}
+
 static void
 meta_window_actor_wayland_class_init (MetaWindowActorWaylandClass *klass)
 {
@@ -177,6 +182,7 @@ meta_window_actor_wayland_class_init (MetaWindowActorWaylandClass *klass)
   window_actor_class->post_paint = meta_window_actor_wayland_post_paint;
   window_actor_class->queue_destroy = meta_window_actor_wayland_queue_destroy;
   window_actor_class->set_frozen = meta_window_actor_wayland_set_frozen;
+  window_actor_class->update_regions = meta_window_actor_wayland_update_regions;
 }
 
 static void

src/compositor/meta-window-actor-x11.c

@@ -1132,7 +1132,7 @@ update_opaque_region (MetaWindowActorX11 *actor_x11)
 }
 
 static void
-check_needs_reshape (MetaWindowActorX11 *actor_x11)
+update_regions (MetaWindowActorX11 *actor_x11)
 {
   if (!actor_x11->needs_reshape)
     return;
@@ -1144,6 +1144,18 @@ check_needs_reshape (MetaWindowActorX11 *actor_x11)
   actor_x11->needs_reshape = FALSE;
 }
 
+static void
+check_needs_reshape (MetaWindowActorX11 *actor_x11)
+{
+  MetaWindow *window =
+    meta_window_actor_get_meta_window (META_WINDOW_ACTOR (actor_x11));
+
+  if (meta_window_x11_always_update_shape (window))
+    return;
+
+  update_regions (actor_x11);
+}
+
 void
 meta_window_actor_x11_update_shape (MetaWindowActorX11 *actor_x11)
 {
@@ -1394,6 +1406,12 @@ meta_window_actor_x11_set_frozen (MetaWindowActor *actor,
     meta_window_x11_thaw_commits (window);
 }
 
+static void
+meta_window_actor_x11_update_regions (MetaWindowActor *actor)
+{
+  update_regions (META_WINDOW_ACTOR_X11 (actor));
+}
+
 static void
 meta_window_actor_x11_set_property (GObject      *object,
                                     guint         prop_id,
@@ -1566,6 +1584,7 @@ meta_window_actor_x11_class_init (MetaWindowActorX11Class *klass)
   window_actor_class->post_paint = meta_window_actor_x11_post_paint;
   window_actor_class->queue_destroy = meta_window_actor_x11_queue_destroy;
   window_actor_class->set_frozen = meta_window_actor_x11_set_frozen;
+  window_actor_class->update_regions = meta_window_actor_x11_update_regions;
 
   actor_class->paint = meta_window_actor_x11_paint;
   actor_class->get_paint_volume = meta_window_actor_x11_get_paint_volume;

src/compositor/meta-window-actor.c

@@ -251,6 +251,12 @@ meta_window_actor_is_frozen (MetaWindowActor *self)
   return priv->surface == NULL || priv->freeze_count > 0;
 }
 
+void
+meta_window_actor_update_regions (MetaWindowActor *self)
+{
+  META_WINDOW_ACTOR_GET_CLASS (self)->update_regions (self);
+}
+
 static void
 meta_window_actor_set_frozen (MetaWindowActor *self,
                               gboolean         frozen)