add pointer constraints

include/labwc.h

@@ -23,7 +23,9 @@
 #include <wlr/types/wlr_output_damage.h>
 #include <wlr/types/wlr_output_management_v1.h>
 #include <wlr/types/wlr_output_layout.h>
+#include <wlr/types/wlr_relative_pointer_v1.h>
 #include <wlr/types/wlr_pointer.h>
+#include <wlr/types/wlr_pointer_constraints_v1.h>
 #include <wlr/types/wlr_seat.h>
 #include <wlr/types/wlr_server_decoration.h>
 #include <wlr/types/wlr_xcursor_manager.h>
@@ -72,6 +74,7 @@ struct seat {
 	struct wlr_cursor *cursor;
 	struct wlr_xcursor_manager *xcursor_manager;
 	struct wlr_drag_icon *drag_icon;
+	struct wlr_pointer_constraint_v1 *current_constraint;
 
 	/* if set, views cannot receive focus */
 	struct wlr_layer_surface_v1 *focused_layer;
@@ -96,6 +99,7 @@ struct seat {
 	struct wl_listener request_start_drag;
 	struct wl_listener start_drag;
 	struct wl_listener destroy_drag;
+	struct wl_listener constraint_commit;
 };
 
 struct server {
@@ -143,6 +147,10 @@ struct server {
 
 	struct wlr_foreign_toplevel_manager_v1 *foreign_toplevel_manager;
 
+	struct wlr_relative_pointer_manager_v1 *relative_pointer_manager;
+	struct wlr_pointer_constraints_v1 *constraints;
+	struct wl_listener new_constraint;
+
 	/* Set when in cycle (alt-tab) mode */
 	struct view *cycle_view;
 
@@ -312,6 +320,12 @@ struct xdg_popup {
 	struct wl_listener new_popup;
 };
 
+struct constraint {
+	struct seat *seat;
+	struct wlr_pointer_constraint_v1 *constraint;
+	struct wl_listener destroy;
+};
+
 void xdg_popup_create(struct view *view, struct wlr_xdg_popup *wlr_popup);
 
 void xdg_toplevel_decoration(struct wl_listener *listener, void *data);
@@ -435,4 +449,8 @@ void osd_update(struct server *server);
 bool input_inhibit_blocks_surface(struct seat *seat,
 	struct wl_resource *resource);
 
+void create_constraint(struct wl_listener *listener, void *data);
+void constrain_cursor(struct server *server, struct wlr_pointer_constraint_v1
+	*constraint);
+
 #endif /* __LABWC_H */

protocols/meson.build

@@ -15,6 +15,7 @@ wayland_scanner_server = generator(
 
 server_protocols = [
 	[wl_protocol_dir, 'stable/xdg-shell/xdg-shell.xml'],
+	[wl_protocol_dir, 'unstable/pointer-constraints/pointer-constraints-unstable-v1.xml'],
 	['wlr-layer-shell-unstable-v1.xml'],
 	['wlr-input-inhibitor-unstable-v1.xml'],
 ]

src/cursor.c

@@ -236,6 +236,81 @@ start_drag(struct wl_listener *listener, void *data)
 	wl_signal_add(&seat->drag_icon->events.destroy, &seat->destroy_drag);
 }
 
+void
+handle_constraint_commit(struct wl_listener *listener, void *data)
+{
+	struct seat *seat = wl_container_of(listener, seat, constraint_commit);
+	struct wlr_pointer_constraint_v1 *constraint = seat->current_constraint;
+	assert(constraint->surface = data);
+}
+
+void
+destroy_constraint(struct wl_listener *listener, void *data)
+{
+	struct constraint *constraint = wl_container_of(listener, constraint,
+		destroy);
+	struct wlr_pointer_constraint_v1 *wlr_constraint = data;
+	struct seat *seat = constraint->seat;
+
+	wl_list_remove(&constraint->destroy.link);
+	if (seat->current_constraint == wlr_constraint) {
+		if (seat->constraint_commit.link.next != NULL) {
+			wl_list_remove(&seat->constraint_commit.link);
+		}
+		wl_list_init(&seat->constraint_commit.link);
+		seat->current_constraint = NULL;
+	}
+
+	free(constraint);
+}
+
+void
+create_constraint(struct wl_listener *listener, void *data)
+{
+	struct wlr_pointer_constraint_v1 *wlr_constraint = data;
+	struct server *server = wl_container_of(listener, server,
+		new_constraint);
+	struct view *view;
+	struct constraint *constraint = calloc(1, sizeof(struct constraint));
+
+	constraint->constraint = wlr_constraint;
+	constraint->seat = &server->seat;
+	constraint->destroy.notify = destroy_constraint;
+	wl_signal_add(&wlr_constraint->events.destroy, &constraint->destroy);
+
+	view = desktop_focused_view(server);
+	if (view->surface == wlr_constraint->surface) {
+		constrain_cursor(server, wlr_constraint);
+	}
+}
+
+void
+constrain_cursor(struct server *server, struct wlr_pointer_constraint_v1
+		*constraint)
+{
+	struct seat *seat = &server->seat;
+	if (seat->current_constraint == constraint) {
+		return;
+	}
+	wl_list_remove(&seat->constraint_commit.link);
+	if (seat->current_constraint) {
+		wlr_pointer_constraint_v1_send_deactivated(
+			seat->current_constraint);
+	}
+
+	seat->current_constraint = constraint;
+
+	if (constraint == NULL) {
+		wl_list_init(&seat->constraint_commit.link);
+		return;
+	}
+
+	wlr_pointer_constraint_v1_send_activated(constraint);
+	seat->constraint_commit.notify = handle_constraint_commit;
+	wl_signal_add(&constraint->surface->events.commit,
+		&seat->constraint_commit);
+}
+
 static void
 cursor_motion(struct wl_listener *listener, void *data)
 {
@@ -244,17 +319,25 @@ cursor_motion(struct wl_listener *listener, void *data)
 	 * _relative_ pointer motion event (i.e. a delta)
 	 */
 	struct seat *seat = wl_container_of(listener, seat, cursor_motion);
+	struct server *server = seat->server;
 	struct wlr_event_pointer_motion *event = data;
 
-	/*
-	 * The cursor doesn't move unless we tell it to. The cursor
-	 * automatically handles constraining the motion to the output layout,
-	 * as well as any special configuration applied for the specific input
-	 * device which generated the event. You can pass NULL for the device
-	 * if you want to move the cursor around without any input.
-	 */
-	wlr_cursor_move(seat->cursor, event->device, event->delta_x,
-		event->delta_y);
+	wlr_relative_pointer_manager_v1_send_relative_motion(
+		server->relative_pointer_manager,
+		seat->seat, (uint64_t)event->time_msec * 1000,
+		event->delta_x, event->delta_y, event->unaccel_dx,
+		event->unaccel_dy);
+	if (!seat->current_constraint) {
+		/*
+		 * The cursor doesn't move unless we tell it to. The cursor
+		 * automatically handles constraining the motion to the output layout,
+		 * as well as any special configuration applied for the specific input
+		 * device which generated the event. You can pass NULL for the device
+		 * if you want to move the cursor around without any input.
+		 */
+		wlr_cursor_move(seat->cursor, event->device, event->delta_x,
+			event->delta_y);
+	}
 	process_cursor_motion(seat->server, event->time_msec);
 }
 

src/seat.c

@@ -181,6 +181,7 @@ seat_init(struct server *server)
 		exit(EXIT_FAILURE);
 	}
 
+	wl_list_init(&seat->constraint_commit.link);
 	wl_list_init(&seat->inputs);
 	seat->new_input.notify = new_input_notify;
 	wl_signal_add(&server->backend->events.new_input, &seat->new_input);
@@ -242,6 +243,12 @@ seat_focus_surface(struct seat *seat, struct wlr_surface *surface)
 	struct wlr_keyboard *kb = &seat->keyboard_group->keyboard;
 	wlr_seat_keyboard_notify_enter(seat->seat, surface, kb->keycodes,
 		kb->num_keycodes, &kb->modifiers);
+
+	struct server *server = seat->server;
+	struct wlr_pointer_constraint_v1 *constraint =
+		wlr_pointer_constraints_v1_constraint_for_surface(server->constraints,
+			surface, seat->seat);
+	constrain_cursor(server, constraint);
 }
 
 void

src/server.c

@@ -269,6 +269,15 @@ server_init(struct server *server)
 	wlr_data_control_manager_v1_create(server->wl_display);
 	wlr_gamma_control_manager_v1_create(server->wl_display);
 
+	server->relative_pointer_manager = wlr_relative_pointer_manager_v1_create(
+		server->wl_display);
+	server->constraints = wlr_pointer_constraints_v1_create(
+		server->wl_display);
+
+	server->new_constraint.notify = create_constraint;
+	wl_signal_add(&server->constraints->events.new_constraint,
+		&server->new_constraint);
+
 	server->input_inhibit =
 		wlr_input_inhibit_manager_create(server->wl_display);
 	if (!server->input_inhibit) {