Support pointer constraints and relative pointer protocols

Fixes: https://codeberg.org/dwl/dwl/issues/489
FIxes: https://codeberg.org/dwl/dwl/issues/317

2 files changed, 127 insertions, 21 deletions

diff --git a/Makefile b/Makefile
index 0822ddc..a67fdd3 100644
--- a/Makefile
+++ b/Makefile
@@ -16,7 +16,7 @@ LDLIBS    = `$(PKG_CONFIG) --libs $(PKGS)` $(LIBS)
 all: dwl
 dwl: dwl.o util.o
 	$(CC) dwl.o util.o $(LDLIBS) $(LDFLAGS) $(DWLCFLAGS) -o $@
-dwl.o: dwl.c config.mk config.h client.h cursor-shape-v1-protocol.h xdg-shell-protocol.h wlr-layer-shell-unstable-v1-protocol.h
+dwl.o: dwl.c config.mk config.h client.h cursor-shape-v1-protocol.h pointer-constraints-unstable-v1-protocol.h wlr-layer-shell-unstable-v1-protocol.h xdg-shell-protocol.h
 util.o: util.c util.h
 
 # wayland-scanner is a tool which generates C headers and rigging for Wayland
@@ -25,15 +25,18 @@ util.o: util.c util.h
 WAYLAND_SCANNER   = `$(PKG_CONFIG) --variable=wayland_scanner wayland-scanner`
 WAYLAND_PROTOCOLS = `$(PKG_CONFIG) --variable=pkgdatadir wayland-protocols`
 
-xdg-shell-protocol.h:
+cursor-shape-v1-protocol.h:
 	$(WAYLAND_SCANNER) server-header \
-		$(WAYLAND_PROTOCOLS)/stable/xdg-shell/xdg-shell.xml $@
+		$(WAYLAND_PROTOCOLS)/staging/cursor-shape/cursor-shape-v1.xml $@
+pointer-constraints-unstable-v1-protocol.h:
+	$(WAYLAND_SCANNER) server-header \
+		$(WAYLAND_PROTOCOLS)/unstable/pointer-constraints/pointer-constraints-unstable-v1.xml $@
 wlr-layer-shell-unstable-v1-protocol.h:
 	$(WAYLAND_SCANNER) server-header \
 		protocols/wlr-layer-shell-unstable-v1.xml $@
-cursor-shape-v1-protocol.h:
+xdg-shell-protocol.h:
 	$(WAYLAND_SCANNER) server-header \
-		$(WAYLAND_PROTOCOLS)/staging/cursor-shape/cursor-shape-v1.xml $@
+		$(WAYLAND_PROTOCOLS)/stable/xdg-shell/xdg-shell.xml $@
 
 config.h:
 	cp config.def.h $@
diff --git a/dwl.c b/dwl.c
index fa76db2..d508d79 100644
--- a/dwl.c
+++ b/dwl.c
@@ -35,9 +35,11 @@
 #include <wlr/types/wlr_output_layout.h>
 #include <wlr/types/wlr_output_management_v1.h>
 #include <wlr/types/wlr_pointer.h>
+#include <wlr/types/wlr_pointer_constraints_v1.h>
 #include <wlr/types/wlr_presentation_time.h>
 #include <wlr/types/wlr_primary_selection.h>
 #include <wlr/types/wlr_primary_selection_v1.h>
+#include <wlr/types/wlr_relative_pointer_v1.h>
 #include <wlr/types/wlr_scene.h>
 #include <wlr/types/wlr_screencopy_v1.h>
 #include <wlr/types/wlr_seat.h>
@@ -54,6 +56,7 @@
 #include <wlr/types/wlr_xdg_output_v1.h>
 #include <wlr/types/wlr_xdg_shell.h>
 #include <wlr/util/log.h>
+#include <wlr/util/region.h>
 #include <xkbcommon/xkbcommon.h>
 #ifdef XWAYLAND
 #include <wlr/xwayland.h>
@@ -215,6 +218,11 @@ typedef struct {
 } MonitorRule;
 
 typedef struct {
+	struct wlr_pointer_constraint_v1 *constraint;
+	struct wl_listener destroy;
+} PointerConstraint;
+
+typedef struct {
 	const char *id;
 	const char *title;
 	uint32_t tags;
@@ -255,7 +263,10 @@ static void createlocksurface(struct wl_listener *listener, void *data);
 static void createmon(struct wl_listener *listener, void *data);
 static void createnotify(struct wl_listener *listener, void *data);
 static void createpointer(struct wlr_pointer *pointer);
+static void createpointerconstraint(struct wl_listener *listener, void *data);
+static void cursorconstrain(struct wlr_pointer_constraint_v1 *constraint);
 static void cursorframe(struct wl_listener *listener, void *data);
+static void cursorwarptohint(void);
 static void destroydecoration(struct wl_listener *listener, void *data);
 static void destroydragicon(struct wl_listener *listener, void *data);
 static void destroyidleinhibitor(struct wl_listener *listener, void *data);
@@ -263,6 +274,7 @@ static void destroylayersurfacenotify(struct wl_listener *listener, void *data);
 static void destroylock(SessionLock *lock, int unlocked);
 static void destroylocksurface(struct wl_listener *listener, void *data);
 static void destroynotify(struct wl_listener *listener, void *data);
+static void destroypointerconstraint(struct wl_listener *listener, void *data);
 static void destroysessionlock(struct wl_listener *listener, void *data);
 static void destroysessionmgr(struct wl_listener *listener, void *data);
 static Monitor *dirtomon(enum wlr_direction dir);
@@ -285,7 +297,8 @@ static void mapnotify(struct wl_listener *listener, void *data);
 static void maximizenotify(struct wl_listener *listener, void *data);
 static void monocle(Monitor *m);
 static void motionabsolute(struct wl_listener *listener, void *data);
-static void motionnotify(uint32_t time);
+static void motionnotify(uint32_t time, struct wlr_input_device *device, double sx,
+		double sy, double sx_unaccel, double sy_unaccel);
 static void motionrelative(struct wl_listener *listener, void *data);
 static void moveresize(const Arg *arg);
 static void outputmgrapply(struct wl_listener *listener, void *data);
@@ -366,6 +379,10 @@ static struct wlr_virtual_keyboard_manager_v1 *virtual_keyboard_mgr;
 static struct wlr_virtual_pointer_manager_v1 *virtual_pointer_mgr;
 static struct wlr_cursor_shape_manager_v1 *cursor_shape_mgr;
 
+static struct wlr_pointer_constraints_v1 *pointer_constraints;
+static struct wlr_relative_pointer_manager_v1 *relative_pointer_mgr;
+static struct wlr_pointer_constraint_v1 *active_constraint;
+
 static struct wlr_cursor *cursor;
 static struct wlr_xcursor_manager *cursor_mgr;
 
@@ -478,7 +495,7 @@ arrange(Monitor *m)
 
 	if (m->lt[m->sellt]->arrange)
 		m->lt[m->sellt]->arrange(m);
-	motionnotify(0);
+	motionnotify(0, NULL, 0, 0, 0, 0);
 	checkidleinhibitor(NULL);
 }
 
@@ -1016,6 +1033,28 @@ createpointer(struct wlr_pointer *pointer)
 }
 
 void
+createpointerconstraint(struct wl_listener *listener, void *data)
+{
+	PointerConstraint *pointer_constraint = ecalloc(1, sizeof(*pointer_constraint));
+	pointer_constraint->constraint = data;
+	LISTEN(&pointer_constraint->constraint->events.destroy,
+			&pointer_constraint->destroy, destroypointerconstraint);
+}
+
+void
+cursorconstrain(struct wlr_pointer_constraint_v1 *constraint)
+{
+	if (active_constraint == constraint)
+		return;
+
+	if (active_constraint)
+		wlr_pointer_constraint_v1_send_deactivated(active_constraint);
+
+	active_constraint = constraint;
+	wlr_pointer_constraint_v1_send_activated(constraint);
+}
+
+void
 cursorframe(struct wl_listener *listener, void *data)
 {
 	/* This event is forwarded by the cursor when a pointer emits an frame
@@ -1027,6 +1066,21 @@ cursorframe(struct wl_listener *listener, void *data)
 }
 
 void
+cursorwarptohint(void)
+{
+	Client *c = NULL;
+	double sx = active_constraint->current.cursor_hint.x;
+	double sy = active_constraint->current.cursor_hint.y;
+
+	toplevel_from_wlr_surface(active_constraint->surface, &c, NULL);
+	/* TODO: wlroots 0.18: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4478 */
+	if (c && (active_constraint->current.committed & WLR_POINTER_CONSTRAINT_V1_STATE_CURSOR_HINT )) {
+		wlr_cursor_warp(cursor, NULL, sx + c->geom.x + c->bw, sy + c->geom.y + c->bw);
+		wlr_seat_pointer_warp(active_constraint->seat, sx, sy);
+	}
+}
+
+void
 destroydecoration(struct wl_listener *listener, void *data)
 {
 	Client *c = wl_container_of(listener, c, destroy_decoration);
@@ -1040,7 +1094,7 @@ destroydragicon(struct wl_listener *listener, void *data)
 {
 	/* Focus enter isn't sent during drag, so refocus the focused node. */
 	focusclient(focustop(selmon), 1);
-	motionnotify(0);
+	motionnotify(0, NULL, 0, 0, 0, 0);
 }
 
 void
@@ -1076,7 +1130,7 @@ destroylock(SessionLock *lock, int unlock)
 	wlr_scene_node_set_enabled(&locked_bg->node, 0);
 
 	focusclient(focustop(selmon), 0);
-	motionnotify(0);
+	motionnotify(0, NULL, 0, 0, 0, 0);
 
 destroy:
 	wl_list_remove(&lock->new_surface.link);
@@ -1136,6 +1190,20 @@ destroynotify(struct wl_listener *listener, void *data)
 }
 
 void
+destroypointerconstraint(struct wl_listener *listener, void *data)
+{
+	PointerConstraint *pointer_constraint = wl_container_of(listener, pointer_constraint, destroy);
+
+	if (active_constraint == pointer_constraint->constraint) {
+		cursorwarptohint();
+		active_constraint = NULL;
+	}
+
+	wl_list_remove(&pointer_constraint->destroy.link);
+	free(pointer_constraint);
+}
+
+void
 destroysessionlock(struct wl_listener *listener, void *data)
 {
 	SessionLock *lock = wl_container_of(listener, lock, destroy);
@@ -1231,7 +1299,7 @@ focusclient(Client *c, int lift)
 	}
 
 	/* Change cursor surface */
-	motionnotify(0);
+	motionnotify(0, NULL, 0, 0, 0, 0);
 
 	/* Have a client, so focus its top-level wlr_surface */
 	client_notify_enter(client_surface(c), wlr_seat_get_keyboard(seat));
@@ -1490,7 +1558,7 @@ locksession(struct wl_listener *listener, void *data)
 void
 maplayersurfacenotify(struct wl_listener *listener, void *data)
 {
-	motionnotify(0);
+	motionnotify(0, NULL, 0, 0, 0, 0);
 }
 
 void
@@ -1605,20 +1673,50 @@ motionabsolute(struct wl_listener *listener, void *data)
 	 * so we have to warp the mouse there. There is also some hardware which
 	 * emits these events. */
 	struct wlr_pointer_motion_absolute_event *event = data;
-	wlr_cursor_warp_absolute(cursor, &event->pointer->base, event->x, event->y);
-	motionnotify(event->time_msec);
+	double lx, ly, dx, dy;
+
+	wlr_cursor_absolute_to_layout_coords(cursor, &event->pointer->base, event->x, event->y, &lx, &ly);
+	dx = lx - cursor->x;
+	dy = ly - cursor->y;
+	motionnotify(event->time_msec, &event->pointer->base, dx, dy, dx, dy);
 }
 
 void
-motionnotify(uint32_t time)
+motionnotify(uint32_t time, struct wlr_input_device *device, double dx, double dy,
+		double dx_unaccel, double dy_unaccel)
 {
-	double sx = 0, sy = 0;
+	double sx = 0, sy = 0, sx_confined, sy_confined;
 	Client *c = NULL, *w = NULL;
 	LayerSurface *l = NULL;
 	struct wlr_surface *surface = NULL;
+	struct wlr_pointer_constraint_v1 *constraint;
 
 	/* time is 0 in internal calls meant to restore pointer focus. */
 	if (time) {
+		wlr_relative_pointer_manager_v1_send_relative_motion(
+				relative_pointer_mgr, seat, (uint64_t)time * 1000,
+				dx, dy, dx_unaccel, dy_unaccel);
+
+		wl_list_for_each(constraint, &pointer_constraints->constraints, link)
+			cursorconstrain(constraint);
+
+		if (active_constraint && cursor_mode != CurResize && cursor_mode != CurMove) {
+			toplevel_from_wlr_surface(active_constraint->surface, &c, NULL);
+			if (c && active_constraint->surface == seat->pointer_state.focused_surface) {
+				sx = cursor->x - c->geom.x - c->bw;
+				sy = cursor->y - c->geom.y - c->bw;
+				if (wlr_region_confine(&active_constraint->region, sx, sy,
+						sx + dx, sy + dy, &sx_confined, &sy_confined)) {
+					dx = sx_confined - sx;
+					dy = sy_confined - sy;
+				}
+
+				if (active_constraint->type == WLR_POINTER_CONSTRAINT_V1_LOCKED)
+					return;
+			}
+		}
+
+		wlr_cursor_move(cursor, device, dx, dy);
 		wlr_idle_notifier_v1_notify_activity(idle_notifier, seat);
 
 		/* Update selmon (even while dragging a window) */
@@ -1672,8 +1770,8 @@ motionrelative(struct wl_listener *listener, void *data)
 	 * 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(cursor, &event->pointer->base, event->delta_x, event->delta_y);
-	motionnotify(event->time_msec);
+	motionnotify(event->time_msec, &event->pointer->base, event->delta_x, event->delta_y,
+			event->unaccel_dx, event->unaccel_dy);
 }
 
 void
@@ -1781,7 +1879,8 @@ pointerfocus(Client *c, struct wlr_surface *surface, double sx, double sy,
 {
 	struct timespec now;
 
-	if (sloppyfocus && time && c && !client_is_unmanaged(c))
+	if ((!active_constraint || active_constraint->surface != surface) &&
+			sloppyfocus && time && c && !client_is_unmanaged(c))
 		focusclient(c, 0);
 
 	/* If surface is NULL, clear pointer focus */
@@ -1800,7 +1899,6 @@ pointerfocus(Client *c, struct wlr_surface *surface, double sx, double sy,
 	 * wlroots makes this a no-op if surface is already focused */
 	wlr_seat_pointer_notify_enter(seat, surface, sx, sy);
 	wlr_seat_pointer_notify_motion(seat, time, sx, sy);
-
 }
 
 void
@@ -2295,6 +2393,11 @@ setup(void)
 	xdg_decoration_mgr = wlr_xdg_decoration_manager_v1_create(dpy);
 	LISTEN_STATIC(&xdg_decoration_mgr->events.new_toplevel_decoration, createdecoration);
 
+	pointer_constraints = wlr_pointer_constraints_v1_create(dpy);
+	LISTEN_STATIC(&pointer_constraints->events.new_constraint, createpointerconstraint);
+
+	relative_pointer_mgr = wlr_relative_pointer_manager_v1_create(dpy);
+
 	/*
 	 * Creates a cursor, which is a wlroots utility for tracking the cursor
 	 * image shown on screen.
@@ -2561,7 +2664,7 @@ unmaplayersurfacenotify(struct wl_listener *listener, void *data)
 		arrangelayers(l->mon);
 	if (l->layer_surface->surface == seat->keyboard_state.focused_surface)
 		focusclient(focustop(selmon), 1);
-	motionnotify(0);
+	motionnotify(0, NULL, 0, 0, 0, 0);
 }
 
 void
@@ -2587,7 +2690,7 @@ unmapnotify(struct wl_listener *listener, void *data)
 
 	wlr_scene_node_destroy(&c->scene->node);
 	printstatus();
-	motionnotify(0);
+	motionnotify(0, NULL, 0, 0, 0, 0);
 }
 
 void