Use view->scene_tree as toplevel for view + some legwork:

desktop.c move_to_front() calls wlr_scene_node_raise_to_top
desktop.c, ssd/include.h add LAB_SSD_{OSD, MENU, LAYER_SURFACE} enums
desktop.c desktop_surface_and_view_at() -> desktop_node_and_view_at()
cursor.c reenable cursor_rebase()
cursor.c reenable button click on layer surface

include/labwc.h

@@ -234,6 +234,7 @@ struct view {
 #endif
 	};
 	struct wlr_surface *surface;
+	struct wlr_scene_tree *scene_tree;
 	struct wlr_scene_node *scene_node;
 
 	bool mapped;
@@ -419,11 +420,13 @@ void desktop_focus_topmost_mapped_view(struct server *server);
 bool isfocusable(struct view *view);
 
 /**
- * desktop_surface_and_view_at - find view and surface at (lx, ly)
- * Note: If surface points to layer-surface, view will be set to NULL
+ * desktop_node_and_view_at - find view and scene_node at (lx, ly)
+ * Note: If node points to layer-surface, view_area will be set
+ * to LAB_SSD_LAYER_SURFACE, if view points to another surface
+ * view_area will be LAB_SSD_CLIENT
  */
-struct view *desktop_surface_and_view_at(struct server *server, double lx,
-	double ly, struct wlr_surface **surface, double *sx, double *sy,
+struct view *desktop_node_and_view_at(struct server *server, double lx,
+	double ly, struct wlr_scene_node **scene_node, double *sx, double *sy,
 	enum ssd_part_type *view_area);
 
 struct view *desktop_view_at_cursor(struct server *server);

include/ssd.h

@@ -26,6 +26,9 @@ enum ssd_part_type {
 	LAB_SSD_CLIENT,
 	LAB_SSD_FRAME,
 	LAB_SSD_ROOT,
+	LAB_SSD_MENU,
+	LAB_SSD_OSD,
+	LAB_SSD_LAYER_SURFACE,
 	LAB_SSD_END_MARKER
 };
 

src/cursor.c

@@ -12,25 +12,29 @@
 #include "ssd.h"
 #include "config/mousebind.h"
 
-// void
-// cursor_rebase(struct seat *seat, uint32_t time_msec)
-// {
-// 	double sx, sy;
-// 	struct wlr_surface *surface;
-// 	enum ssd_part_type view_area = LAB_SSD_NONE;
-//
-// 	desktop_surface_and_view_at(seat->server, seat->cursor->x,
-// 		seat->cursor->y, &surface, &sx, &sy, &view_area);
-//
-// 	if (surface) {
-// 		wlr_seat_pointer_notify_clear_focus(seat->seat);
-// 		wlr_seat_pointer_notify_enter(seat->seat, surface, sx, sy);
-// 		wlr_seat_pointer_notify_motion(seat->seat, time_msec, sx, sy);
-// 	} else {
-// 		cursor_set(seat, "left_ptr");
-// 		wlr_seat_pointer_notify_clear_focus(seat->seat);
-// 	}
-// }
+void
+cursor_rebase(struct seat *seat, uint32_t time_msec)
+{
+	double sx, sy;
+	struct wlr_scene_node *node;
+	enum ssd_part_type view_area = LAB_SSD_NONE;
+	struct wlr_surface *surface = NULL;
+
+	desktop_node_and_view_at(seat->server, seat->cursor->x,
+		seat->cursor->y, &node, &sx, &sy, &view_area);
+	if (view_area == LAB_SSD_CLIENT || view_area == LAB_SSD_LAYER_SURFACE) {
+		surface = wlr_scene_surface_from_node(node)->surface;
+	}
+
+	if (surface) {
+		wlr_seat_pointer_notify_clear_focus(seat->seat);
+		wlr_seat_pointer_notify_enter(seat->seat, surface, sx, sy);
+		wlr_seat_pointer_notify_motion(seat->seat, time_msec, sx, sy);
+	} else {
+		cursor_set(seat, "left_ptr");
+		wlr_seat_pointer_notify_clear_focus(seat->seat);
+	}
+}
 
 static void
 request_cursor_notify(struct wl_listener *listener, void *data)
@@ -201,12 +205,17 @@ process_cursor_motion(struct server *server, uint32_t time)
 	/* Otherwise, find view under the pointer and send the event along */
 	double sx, sy;
 	struct wlr_seat *wlr_seat = server->seat.seat;
-	struct wlr_surface *surface = NULL;
+	struct wlr_scene_node *node;
 	enum ssd_part_type view_area = LAB_SSD_NONE;
-	struct view *view = desktop_surface_and_view_at(server,
-		server->seat.cursor->x, server->seat.cursor->y, &surface,
+	struct view *view = desktop_node_and_view_at(server,
+		server->seat.cursor->x, server->seat.cursor->y, &node,
 		&sx, &sy, &view_area);
 
+	struct wlr_surface *surface = NULL;
+	if (view_area == LAB_SSD_CLIENT || view_area == LAB_SSD_LAYER_SURFACE) {
+		surface = wlr_scene_surface_from_node(node)->surface;
+	}
+
 	/* resize handles */
 	uint32_t resize_edges = ssd_resize_edges(view_area);
 
@@ -593,17 +602,22 @@ cursor_button(struct wl_listener *listener, void *data)
 	wlr_idle_notify_activity(seat->wlr_idle, seat->seat);
 
 	double sx, sy;
-	struct wlr_surface *surface;
+	struct wlr_scene_node *node;
 	enum ssd_part_type view_area = LAB_SSD_NONE;
 	uint32_t resize_edges;
 
 	/* bindings to the Frame context swallow mouse events if activated */
 	bool triggered_frame_binding = false;
 
-	struct view *view = desktop_surface_and_view_at(server,
-		server->seat.cursor->x, server->seat.cursor->y, &surface,
+	struct view *view = desktop_node_and_view_at(server,
+		server->seat.cursor->x, server->seat.cursor->y, &node,
 		&sx, &sy, &view_area);
 
+	struct wlr_surface *surface = NULL;
+	if (view_area == LAB_SSD_CLIENT || view_area == LAB_SSD_LAYER_SURFACE) {
+		surface = wlr_scene_surface_from_node(node)->surface;
+	}
+
 	/* get modifiers */
 	struct wlr_input_device *device = seat->keyboard_group->input_device;
 	uint32_t modifiers = wlr_keyboard_get_modifiers(device->keyboard);
@@ -622,7 +636,7 @@ cursor_button(struct wl_listener *listener, void *data)
 				server->input_mode = LAB_INPUT_STATE_PASSTHROUGH;
 				server->grabbed_view = NULL;
 			}
-//			cursor_rebase(&server->seat, event->time_msec);
+			cursor_rebase(&server->seat, event->time_msec);
 		}
 
 		/* Handle _release_ on root window */
@@ -640,24 +654,24 @@ cursor_button(struct wl_listener *listener, void *data)
 			menu_action_selected(server, server->windowmenu);
 		}
 		server->input_mode = LAB_INPUT_STATE_PASSTHROUGH;
-//		cursor_rebase(&server->seat, event->time_msec);
+		cursor_rebase(&server->seat, event->time_msec);
 		return;
 	}
 
 	/* Handle _press_ on a layer surface */
-// 	if (!view && surface) {
-// 		if (!wlr_surface_is_layer_surface(surface)) {
-// 			return;
-// 		}
-// 		struct wlr_layer_surface_v1 *layer =
-// 			wlr_layer_surface_v1_from_wlr_surface(surface);
-// 		if (layer->current.keyboard_interactive) {
-// 			seat_set_focus_layer(&server->seat, layer);
-// 		}
-// 		wlr_seat_pointer_notify_button(seat->seat, event->time_msec,
-// 			event->button, event->state);
-// 		return;
-// 	}
+	if (view_area == LAB_SSD_LAYER_SURFACE && surface) {
+		if (!wlr_surface_is_layer_surface(surface)) {
+			return;
+		}
+		struct wlr_layer_surface_v1 *layer =
+			wlr_layer_surface_v1_from_wlr_surface(surface);
+		if (layer->current.keyboard_interactive) {
+			seat_set_focus_layer(&server->seat, layer);
+		}
+		wlr_seat_pointer_notify_button(seat->seat, event->time_msec,
+			event->button, event->state);
+		return;
+	}
 
 	/* Handle _press_ on root window */
 	if (!view) {
@@ -704,7 +718,7 @@ cursor_axis(struct wl_listener *listener, void *data)
 	wlr_idle_notify_activity(seat->wlr_idle, seat->seat);
 
 	/* Notify the client with pointer focus of the axis event. */
-//	cursor_rebase(seat, event->time_msec);
+	cursor_rebase(seat, event->time_msec);
 	wlr_seat_pointer_notify_axis(seat->seat, event->time_msec,
 		event->orientation, event->delta, event->delta_discrete,
 		event->source);

src/desktop.c

@@ -10,6 +10,7 @@ move_to_front(struct view *view)
 {
 	wl_list_remove(&view->link);
 	wl_list_insert(&view->server->views, &view->link);
+	wlr_scene_node_raise_to_top(&view->scene_tree->node);
 }
 
 #if HAVE_XWAYLAND
@@ -256,32 +257,57 @@ desktop_focus_topmost_mapped_view(struct server *server)
 }
 
 struct view *
-desktop_surface_and_view_at(struct server *server, double lx, double ly,
-		struct wlr_surface **surface, double *sx, double *sy,
+desktop_node_and_view_at(struct server *server, double lx, double ly,
+		struct wlr_scene_node **scene_node, double *sx, double *sy,
 		enum ssd_part_type *view_area)
 {
 	struct wlr_scene_node *node =
 		wlr_scene_node_at(&server->scene->node, lx, ly, sx, sy);
 
-	if (!node || node->type != WLR_SCENE_NODE_SURFACE) {
+	*scene_node = node;
+	if (!node) {
+		*view_area = LAB_SSD_NONE;
 		return NULL;
 	}
-	*surface = wlr_scene_surface_from_node(node)->surface;
+	if (node->type == WLR_SCENE_NODE_SURFACE) {
+		struct wlr_surface *surface =
+			wlr_scene_surface_from_node(node)->surface;
+		if (wlr_surface_is_layer_surface(surface)) {
+			*view_area = LAB_SSD_LAYER_SURFACE;
+			return NULL;
+		}
+		*view_area = LAB_SSD_CLIENT;
+	} else {
+		/* TODO: remove */
+		*view_area = LAB_SSD_NONE;
+	}
+	struct wlr_scene_node *osd = &server->osd_tree->node;
 	while (node && !node->data) {
+		if (node == osd) {
+			*view_area = LAB_SSD_OSD;
+			return NULL;
+		}
+		/* TODO: node == &server->menu_tree->node */
 		node = node->parent;
 	}
-	assert(node);
-	return node->data;
+	if (!node) {
+		wlr_log(WLR_ERROR, "Unknown node detected");
+		*view_area = LAB_SSD_NONE;
+		return NULL;
+	}
+	struct view *view = node->data;
+	/* TODO: *view_area = ssd_get_type(view, node) */
+	return view;
 }
 
 struct view *
 desktop_view_at_cursor(struct server *server)
 {
 	double sx, sy;
-	struct wlr_surface *surface;
+	struct wlr_scene_node *node;
 	enum ssd_part_type view_area = LAB_SSD_NONE;
 
-	return desktop_surface_and_view_at(server,
+	return desktop_node_and_view_at(server,
 			server->seat.cursor->x, server->seat.cursor->y,
-			&surface, &sx, &sy, &view_area);
+			&node, &sx, &sy, &view_area);
 }

src/view.c

@@ -31,7 +31,7 @@ view_move(struct view *view, double x, double y)
 		view->impl->move(view, x, y);
 	}
 	view_discover_output(view);
-	wlr_scene_node_set_position(view->scene_node, view->x, view->y);
+	wlr_scene_node_set_position(&view->scene_tree->node, view->x, view->y);
 }
 
 void
@@ -45,7 +45,7 @@ view_move_resize(struct view *view, struct wlr_box geo)
 	}
 	ssd_update_title(view);
 	view_discover_output(view);
-	wlr_scene_node_set_position(view->scene_node, view->x, view->y);
+	wlr_scene_node_set_position(&view->scene_tree->node, view->x, view->y);
 }
 
 #define MIN_VIEW_WIDTH (100)
@@ -147,7 +147,7 @@ view_center(struct view *view)
 	if (view_compute_centered_position(view, view->w, view->h, &x, &y)) {
 		view_move(view, x, y);
 	}
-	wlr_scene_node_set_position(view->scene_node, view->x, view->y);
+	wlr_scene_node_set_position(&view->scene_tree->node, view->x, view->y);
 }
 
 static void
@@ -223,7 +223,7 @@ view_maximize(struct view *view, bool maximize)
 	if (view->fullscreen) {
 		return;
 	}
-	wlr_scene_node_set_position(view->scene_node, view->x, view->y);
+	wlr_scene_node_set_position(&view->scene_tree->node, view->x, view->y);
 	if (view->impl->maximize) {
 		view->impl->maximize(view, maximize);
 	}

src/xdg.c

@@ -86,7 +86,11 @@ handle_destroy(struct wl_listener *listener, void *data)
 	interactive_end(view);
 	wl_list_remove(&view->link);
 	wl_list_remove(&view->destroy.link);
+	if (view->scene_tree) {
 		ssd_destroy(view);
+		wlr_scene_node_destroy(&view->scene_tree->node);
+		view->scene_tree = NULL;
+	}
 	free(view);
 }
 
@@ -388,13 +392,17 @@ xdg_surface_new(struct wl_listener *listener, void *data)
 	view->xdg_surface = xdg_surface;
 	wl_list_init(&view->ssd.parts);
 
+	view->scene_tree = wlr_scene_tree_create(&view->server->view_tree->node);
 	view->scene_node = wlr_scene_xdg_surface_create(
-		&view->server->view_tree->node, view->xdg_surface);
+		&view->scene_tree->node, view->xdg_surface);
 	if (!view->scene_node) {
+		wlr_scene_node_destroy(&view->scene_tree->node);
+		view->scene_tree = NULL;
 		wl_resource_post_no_memory(view->surface->resource);
+		/* TODO: should we free(view) here? */
 		return;
 	}
-	view->scene_node->data = view;
+	view->scene_tree->node.data = view;
 
 	/* In support of xdg_toplevel_decoration */
 	xdg_surface->data = view;

src/xwayland.c

@@ -90,7 +90,11 @@ handle_destroy(struct wl_listener *listener, void *data)
 	wl_list_remove(&view->request_configure.link);
 	wl_list_remove(&view->request_maximize.link);
 	wl_list_remove(&view->request_fullscreen.link);
+	if (view->scene_tree) {
 		ssd_destroy(view);
+		wlr_scene_node_destroy(&view->scene_tree->node);
+		view->scene_tree = NULL;
+	}
 	free(view);
 }
 
@@ -256,13 +260,17 @@ map(struct view *view)
 	}
 	view->surface = view->xwayland_surface->surface;
 
+	view->scene_tree = wlr_scene_tree_create(&view->server->view_tree->node);
 	view->scene_node = wlr_scene_subsurface_tree_create(
-		&view->server->view_tree->node, view->surface);
+		&view->scene_tree->node, view->surface);
 	if (!view->scene_node) {
+		wlr_scene_node_destroy(&view->scene_tree->node);
+		view->scene_tree = NULL;
 		wl_resource_post_no_memory(view->surface->resource);
+		/* TODO: should we free(view) here? */
 		return;
 	}
-	view->scene_node->data = view;
+	view->scene_tree->node.data = view;
 
 	view->ssd.enabled = want_deco(view);