subsurface stacking requests

include/wlr/types/wlr_surface.h

@@ -48,8 +48,10 @@ struct wlr_subsurface {
 	bool has_cache;
 
 	bool synchronized;
+	bool reordered;
 
 	struct wl_list parent_link;
+	struct wl_list parent_pending_link;
 };
 
 struct wlr_surface {
@@ -76,6 +78,8 @@ struct wlr_surface {
 	struct wlr_subsurface *subsurface;
 	struct wl_list subsurface_list; // wlr_subsurface::parent_link
 
+	// wlr_subsurface::parent_pending_link
+	struct wl_list subsurface_pending_list;
 	void *data;
 };
 

types/wlr_surface.c

@@ -290,12 +290,44 @@ static void wlr_surface_move_state(struct wlr_surface *surface, struct wlr_surfa
 	next->invalid = 0;
 }
 
+static void wlr_surface_damage_subsurfaces(struct wlr_subsurface *subsurface) {
+	// XXX: This is probably the wrong way to do it, because this damage should
+	// come from the client, but weston doesn't do it correctly either and it
+	// seems to work ok. See the comment on weston_surface_damage for more info
+	// about a better approach.
+	struct wlr_surface *surface = subsurface->surface;
+	pixman_region32_union_rect(&surface->current->surface_damage,
+		&surface->current->surface_damage,
+		0, 0, surface->current->width,
+		surface->current->height);
+
+	subsurface->reordered = false;
+
+	struct wlr_subsurface *child;
+	wl_list_for_each(child, &subsurface->surface->subsurface_list, parent_link) {
+		wlr_surface_damage_subsurfaces(child);
+	}
+}
+
 static void wlr_surface_commit_pending(struct wlr_surface *surface) {
 	int32_t oldw = surface->current->buffer_width;
 	int32_t oldh = surface->current->buffer_height;
 
 	wlr_surface_move_state(surface, surface->pending, surface->current);
 
+	// commit subsurface order
+	struct wlr_subsurface *subsurface;
+	wl_list_for_each_reverse(subsurface, &surface->subsurface_pending_list,
+		parent_pending_link) {
+		wl_list_remove(&subsurface->parent_link);
+		wl_list_insert(&surface->subsurface_list, &subsurface->parent_link);
+
+		if (subsurface->reordered) {
+			// TODO: damage all the subsurfaces
+			wlr_surface_damage_subsurfaces(subsurface);
+		}
+	}
+
 	surface->reupload_buffer = oldw != surface->current->buffer_width ||
 		oldh != surface->current->buffer_height;
 
@@ -546,6 +578,7 @@ struct wlr_surface *wlr_surface_create(struct wl_resource *res,
 	wl_signal_init(&surface->signals.commit);
 	wl_signal_init(&surface->signals.destroy);
 	wl_list_init(&surface->subsurface_list);
+	wl_list_init(&surface->subsurface_pending_list);
 	wl_resource_set_implementation(res, &surface_interface,
 		surface, destroy_surface);
 	return surface;
@@ -612,14 +645,69 @@ static void subsurface_set_position(struct wl_client *client,
 	surface->pending->subsurface_position.y = y;
 }
 
+static struct wlr_subsurface *subsurface_find_sibling(
+		struct wlr_subsurface *subsurface, struct wlr_surface *surface) {
+	struct wlr_surface *parent = subsurface->parent;
+
+	struct wlr_subsurface *sibling;
+	wl_list_for_each(sibling, &parent->subsurface_list, parent_link) {
+		if (sibling->surface == surface && sibling != subsurface)
+			return sibling;
+	}
+
+	return NULL;
+}
+
 static void subsurface_place_above(struct wl_client *client,
-		struct wl_resource *resource, struct wl_resource *sibling) {
-	wlr_log(L_DEBUG, "TODO: subsurface place above");
+		struct wl_resource *resource, struct wl_resource *sibling_resource) {
+	struct wlr_subsurface *subsurface = wl_resource_get_user_data(resource);
+
+	if (!subsurface) {
+		return;
+	}
+
+	struct wlr_surface *sibling_surface =
+		wl_resource_get_user_data(sibling_resource);
+	struct wlr_subsurface *sibling =
+		subsurface_find_sibling(subsurface, sibling_surface);
+
+	if (!sibling) {
+		wl_resource_post_error(subsurface->resource,
+			WL_SUBSURFACE_ERROR_BAD_SURFACE,
+			"%s: wl_surface@%d is not a parent or sibling",
+			"place_above", wl_resource_get_id(sibling_surface->resource));
+		return;
+	}
+
+	wl_list_remove(&subsurface->parent_pending_link);
+	wl_list_insert(sibling->parent_pending_link.prev,
+		&subsurface->parent_pending_link);
+
+	subsurface->reordered = true;
 }
 
 static void subsurface_place_below(struct wl_client *client,
-		struct wl_resource *resource, struct wl_resource *sibling) {
-	wlr_log(L_DEBUG, "TODO: subsurface place below");
+		struct wl_resource *resource, struct wl_resource *sibling_resource) {
+	struct wlr_subsurface *subsurface = wl_resource_get_user_data(resource);
+
+	struct wlr_surface *sibling_surface =
+		wl_resource_get_user_data(sibling_resource);
+	struct wlr_subsurface *sibling =
+		subsurface_find_sibling(subsurface, sibling_surface);
+
+	if (!sibling) {
+		wl_resource_post_error(subsurface->resource,
+			WL_SUBSURFACE_ERROR_BAD_SURFACE,
+			"%s: wl_surface@%d is not a parent or sibling",
+			"place_below", wl_resource_get_id(sibling_surface->resource));
+		return;
+	}
+
+	wl_list_remove(&subsurface->parent_pending_link);
+	wl_list_insert(&sibling->parent_pending_link,
+		&subsurface->parent_pending_link);
+
+	subsurface->reordered = true;
 }
 
 static void subsurface_set_sync(struct wl_client *client,