Implement pointer-constraints-unstable-v1

include/sway/input/cursor.h

@@ -2,6 +2,7 @@
 #define _SWAY_INPUT_CURSOR_H
 #include <stdbool.h>
 #include <stdint.h>
+#include <wlr/types/wlr_pointer_constraints_v1.h>
 #include <wlr/types/wlr_surface.h>
 #include "sway/input/seat.h"
 
@@ -26,6 +27,9 @@ struct sway_cursor {
 	struct wlr_surface *image_surface;
 	int hotspot_x, hotspot_y;
 
+	struct wlr_pointer_constraint_v1 *active_constraint;
+	pixman_region32_t confine; // invalid if active_constraint == NULL
+
 	struct wl_listener motion;
 	struct wl_listener motion_absolute;
 	struct wl_listener button;
@@ -43,6 +47,8 @@ struct sway_cursor {
 
 	struct wl_listener request_set_cursor;
 
+	struct wl_listener constraint_commit;
+
 	struct wl_event_source *hide_source;
 	bool hidden;
 
@@ -75,7 +81,8 @@ int cursor_get_timeout(struct sway_cursor *cursor);
  * Like cursor_rebase, but also allows focus to change when the cursor enters a
  * new container.
  */
-void cursor_send_pointer_motion(struct sway_cursor *cursor, uint32_t time_msec);
+void cursor_send_pointer_motion(struct sway_cursor *cursor, uint32_t time_msec,
+	struct sway_node *node, struct wlr_surface *surface, double sx, double sy);
 
 void dispatch_cursor_button(struct sway_cursor *cursor,
 	struct wlr_input_device *device, uint32_t time_msec, uint32_t button,
@@ -97,6 +104,10 @@ void cursor_warp_to_container(struct sway_cursor *cursor,
 void cursor_warp_to_workspace(struct sway_cursor *cursor,
 		struct sway_workspace *workspace);
 
+
+void sway_cursor_constrain(struct sway_cursor *cursor,
+	struct wlr_pointer_constraint_v1 *constraint);
+
 uint32_t get_mouse_bindsym(const char *name, char **error);
 
 uint32_t get_mouse_bindcode(const char *name, char **error);

include/sway/input/seat.h

@@ -84,6 +84,12 @@ struct sway_seat {
 	struct wl_list link; // input_manager::seats
 };
 
+struct sway_pointer_constraint {
+	struct wlr_pointer_constraint_v1 *constraint;
+
+	struct wl_listener destroy;
+};
+
 struct sway_seat *seat_create(const char *seat_name);
 
 void seat_destroy(struct sway_seat *seat);

include/sway/server.h

@@ -61,6 +61,9 @@ struct sway_server {
 
 	struct wlr_presentation *presentation;
 
+	struct wlr_pointer_constraints_v1 *pointer_constraints;
+	struct wl_listener pointer_constraint;
+
 	size_t txn_timeout_ms;
 	list_t *transactions;
 	list_t *dirty_nodes;
@@ -86,5 +89,6 @@ void handle_xwayland_surface(struct wl_listener *listener, void *data);
 #endif
 void handle_server_decoration(struct wl_listener *listener, void *data);
 void handle_xdg_decoration(struct wl_listener *listener, void *data);
+void handle_pointer_constraint(struct wl_listener *listener, void *data);
 
 #endif

protocols/meson.build

@@ -39,6 +39,7 @@ server_protocols = [
 	[wl_protocol_dir, 'stable/xdg-shell/xdg-shell.xml'],
 	[wl_protocol_dir, 'unstable/xdg-shell/xdg-shell-unstable-v6.xml'],
 	[wl_protocol_dir, 'unstable/xdg-output/xdg-output-unstable-v1.xml'],
+	[wl_protocol_dir, 'unstable/pointer-constraints/pointer-constraints-unstable-v1.xml'],
 	['wlr-layer-shell-unstable-v1.xml'],
 	['wlr-input-inhibitor-unstable-v1.xml'],
 ]

sway/input/cursor.c

@@ -1,4 +1,5 @@
 #define _POSIX_C_SOURCE 200809L
+#include <assert.h>
 #include <math.h>
 #include <libevdev/libevdev.h>
 #include <linux/input-event-codes.h>
@@ -6,10 +7,11 @@
 #include <float.h>
 #include <limits.h>
 #include <strings.h>
+#include <wlr/types/wlr_box.h>
 #include <wlr/types/wlr_cursor.h>
-#include <wlr/types/wlr_xcursor_manager.h>
 #include <wlr/types/wlr_idle.h>
-#include <wlr/types/wlr_box.h>
+#include <wlr/types/wlr_xcursor_manager.h>
+#include <wlr/util/region.h>
 #include "list.h"
 #include "log.h"
 #include "config.h"
@@ -327,8 +329,9 @@ void cursor_unhide(struct sway_cursor *cursor) {
 	cursor_rebase(cursor);
 }
 
-void cursor_send_pointer_motion(struct sway_cursor *cursor,
-		uint32_t time_msec) {
+void cursor_send_pointer_motion(struct sway_cursor *cursor, uint32_t time_msec,
+		struct sway_node *node, struct wlr_surface *surface,
+		double sx, double sy) {
 	if (time_msec == 0) {
 		time_msec = get_current_time_msec();
 	}
@@ -343,12 +346,7 @@ void cursor_send_pointer_motion(struct sway_cursor *cursor,
 		return;
 	}
 
-	struct wlr_surface *surface = NULL;
-	double sx, sy;
-
 	struct sway_node *prev_node = cursor->previous.node;
-	struct sway_node *node = node_at_coords(seat,
-			cursor->cursor->x, cursor->cursor->y, &surface, &sx, &sy);
 
 	// Update the stored previous position
 	cursor->previous.x = cursor->cursor->x;
@@ -401,9 +399,62 @@ static void handle_cursor_motion(struct wl_listener *listener, void *data) {
 	struct sway_cursor *cursor = wl_container_of(listener, cursor, motion);
 	struct wlr_event_pointer_motion *event = data;
 	cursor_handle_activity(cursor);
-	wlr_cursor_move(cursor->cursor, event->device,
-		event->delta_x, event->delta_y);
-	cursor_send_pointer_motion(cursor, event->time_msec);
+
+	double dx = event->delta_x;
+	double dy = event->delta_y;
+
+	struct wlr_surface *surface = NULL;
+	double sx, sy;
+	struct sway_node *node = node_at_coords(cursor->seat,
+		cursor->cursor->x, cursor->cursor->y, &surface, &sx, &sy);
+
+	if (cursor->active_constraint) {
+		if (cursor->active_constraint->surface != surface) {
+			return;
+		}
+
+		double sx_confined, sy_confined;
+		if (!wlr_region_confine(&cursor->confine, sx, sy, sx + dx, sy + dy,
+				&sx_confined, &sy_confined)) {
+			return;
+		}
+
+		dx = sx_confined - sx;
+		dy = sy_confined - sy;
+	}
+
+	wlr_cursor_move(cursor->cursor, event->device, dx, dy);
+	cursor_send_pointer_motion(cursor, event->time_msec, node, surface,
+		sx + dx, sy + dy);
+	transaction_commit_dirty();
+}
+
+static void cursor_motion_absolute(struct sway_cursor *cursor,
+		uint32_t time_msec, struct wlr_input_device *dev,
+		double x, double y) {
+	cursor_handle_activity(cursor);
+
+	double lx, ly;
+	wlr_cursor_absolute_to_layout_coords(cursor->cursor, dev,
+		x, y, &lx, &ly);
+
+	struct wlr_surface *surface = NULL;
+	double sx, sy;
+	struct sway_node *node = node_at_coords(cursor->seat,
+		lx, ly, &surface, &sx, &sy);
+
+	if (cursor->active_constraint) {
+		if (cursor->active_constraint->surface != surface) {
+			return;
+		}
+		if (!pixman_region32_contains_point(&cursor->confine,
+				floor(sx), floor(sy), NULL)) {
+			return;
+		}
+	}
+
+	wlr_cursor_warp_closest(cursor->cursor, dev, lx, ly);
+	cursor_send_pointer_motion(cursor, time_msec, node, surface, sx, sy);
 	transaction_commit_dirty();
 }
 
@@ -412,10 +463,9 @@ static void handle_cursor_motion_absolute(
 	struct sway_cursor *cursor =
 		wl_container_of(listener, cursor, motion_absolute);
 	struct wlr_event_pointer_motion_absolute *event = data;
-	cursor_handle_activity(cursor);
-	wlr_cursor_warp_absolute(cursor->cursor, event->device, event->x, event->y);
-	cursor_send_pointer_motion(cursor, event->time_msec);
-	transaction_commit_dirty();
+
+	cursor_motion_absolute(cursor, event->time_msec, event->device,
+		event->x, event->y);
 }
 
 /**
@@ -961,9 +1011,7 @@ static void handle_tool_axis(struct wl_listener *listener, void *data) {
 		apply_mapping_from_region(event->device, ic->mapped_from_region, &x, &y);
 	}
 
-	wlr_cursor_warp_absolute(cursor->cursor, event->device, x, y);
-	cursor_send_pointer_motion(cursor, event->time_msec);
-	transaction_commit_dirty();
+	cursor_motion_absolute(cursor, event->time_msec, event->device, x, y);
 }
 
 static void handle_tool_tip(struct wl_listener *listener, void *data) {
@@ -1001,6 +1049,49 @@ static void handle_tool_button(struct wl_listener *listener, void *data) {
 	transaction_commit_dirty();
 }
 
+static void check_constraint_region(struct sway_cursor *cursor) {
+	struct wlr_pointer_constraint_v1 *constraint = cursor->active_constraint;
+	pixman_region32_t *region = &constraint->region;
+	struct sway_view *view = view_from_wlr_surface(constraint->surface);
+	if (view) {
+		struct sway_container *con = view->container;
+
+		double sx = cursor->cursor->x - con->content_x + view->geometry.x;
+		double sy = cursor->cursor->y - con->content_y + view->geometry.y;
+
+		if (!pixman_region32_contains_point(region,
+				floor(sx), floor(sy), NULL)) {
+			int nboxes;
+			pixman_box32_t *boxes = pixman_region32_rectangles(region, &nboxes);
+			if (nboxes > 0) {
+				double sx = (boxes[0].x1 + boxes[0].x2) / 2.;
+				double sy = (boxes[0].y1 + boxes[0].y2) / 2.;
+
+				wlr_cursor_warp_closest(cursor->cursor, NULL,
+					sx + con->content_x - view->geometry.x,
+					sy + con->content_y - view->geometry.y);
+			}
+		}
+	}
+
+	// A locked pointer will result in an empty region, thus disallowing all movement
+	if (constraint->type == WLR_POINTER_CONSTRAINT_V1_CONFINED) {
+		pixman_region32_copy(&cursor->confine, region);
+	} else {
+		pixman_region32_clear(&cursor->confine);
+	}
+}
+
+static void handle_constraint_commit(struct wl_listener *listener,
+		void *data) {
+	struct sway_cursor *cursor =
+		wl_container_of(listener, cursor, constraint_commit);
+	struct wlr_pointer_constraint_v1 *constraint = cursor->active_constraint;
+	assert(constraint->surface == data);
+
+	check_constraint_region(cursor);
+}
+
 static void handle_request_set_cursor(struct wl_listener *listener,
 		void *data) {
 	struct sway_cursor *cursor =
@@ -1162,6 +1253,8 @@ struct sway_cursor *sway_cursor_create(struct sway_seat *seat) {
 			&cursor->request_set_cursor);
 	cursor->request_set_cursor.notify = handle_request_set_cursor;
 
+	wl_list_init(&cursor->constraint_commit.link);
+
 	cursor->cursor = wlr_cursor;
 
 	return cursor;
@@ -1284,3 +1377,107 @@ const char *get_mouse_button_name(uint32_t button) {
 	}
 	return name;
 }
+
+static void warp_to_constraint_cursor_hint(struct sway_cursor *cursor) {
+	struct wlr_pointer_constraint_v1 *constraint = cursor->active_constraint;
+
+	if (constraint->current.committed &
+			WLR_POINTER_CONSTRAINT_V1_STATE_CURSOR_HINT) {
+		double sx = constraint->current.cursor_hint.x;
+		double sy = constraint->current.cursor_hint.y;
+
+		struct sway_view *view = view_from_wlr_surface(constraint->surface);
+		struct sway_container *con = view->container;
+
+		double lx = sx + con->content_x - view->geometry.x;
+		double ly = sy + con->content_y - view->geometry.y;
+
+		wlr_cursor_warp(cursor->cursor, NULL, lx, ly);
+	}
+}
+
+void handle_constraint_destroy(struct wl_listener *listener, void *data) {
+	struct sway_pointer_constraint *sway_constraint =
+		wl_container_of(listener, sway_constraint, destroy);
+	struct wlr_pointer_constraint_v1 *constraint = data;
+	struct sway_seat *seat = constraint->seat->data;
+	struct sway_cursor *cursor = seat->cursor;
+
+	wl_list_remove(&sway_constraint->destroy.link);
+
+	if (cursor->active_constraint == constraint) {
+		warp_to_constraint_cursor_hint(cursor);
+
+		if (cursor->constraint_commit.link.next != NULL) {
+			wl_list_remove(&cursor->constraint_commit.link);
+		}
+		wl_list_init(&cursor->constraint_commit.link);
+		cursor->active_constraint = NULL;
+	}
+
+	free(sway_constraint);
+}
+
+void handle_pointer_constraint(struct wl_listener *listener, void *data) {
+	struct wlr_pointer_constraint_v1 *constraint = data;
+	struct sway_seat *seat = constraint->seat->data;
+
+	struct sway_pointer_constraint *sway_constraint =
+		calloc(1, sizeof(struct sway_pointer_constraint));
+	sway_constraint->constraint = constraint;
+
+	sway_constraint->destroy.notify = handle_constraint_destroy;
+	wl_signal_add(&constraint->events.destroy, &sway_constraint->destroy);
+
+	struct sway_node *focus = seat_get_focus(seat);
+	if (focus && focus->type == N_CONTAINER && focus->sway_container->view) {
+		struct wlr_surface *surface = focus->sway_container->view->surface;
+		if (surface == constraint->surface) {
+			sway_cursor_constrain(seat->cursor, constraint);
+		}
+	}
+}
+
+void sway_cursor_constrain(struct sway_cursor *cursor,
+		struct wlr_pointer_constraint_v1 *constraint) {
+	if (cursor->active_constraint == constraint) {
+		return;
+	}
+
+	wl_list_remove(&cursor->constraint_commit.link);
+	if (cursor->active_constraint) {
+		if (constraint == NULL) {
+			warp_to_constraint_cursor_hint(cursor);
+		}
+		wlr_pointer_constraint_v1_send_deactivated(
+			cursor->active_constraint);
+	}
+
+	cursor->active_constraint = constraint;
+
+	if (constraint == NULL) {
+		wl_list_init(&cursor->constraint_commit.link);
+		return;
+	}
+
+	// FIXME: Big hack, stolen from wlr_pointer_constraints_v1.c:121.
+	// This is necessary because the focus may be set before the surface
+	// has finished committing, which means that warping won't work properly,
+	// since this code will be run *after* the focus has been set.
+	// That is why we duplicate the code here.
+	if (pixman_region32_not_empty(&constraint->current.region)) {
+		pixman_region32_intersect(&constraint->region,
+			&constraint->surface->input_region, &constraint->current.region);
+	} else {
+		pixman_region32_copy(&constraint->region,
+			&constraint->surface->input_region);
+	}
+
+	check_constraint_region(cursor);
+
+	wlr_pointer_constraint_v1_send_activated(constraint);
+
+	cursor->constraint_commit.notify = handle_constraint_commit;
+	wl_signal_add(&constraint->surface->events.commit,
+		&cursor->constraint_commit);
+}

sway/input/seat.c

@@ -105,6 +105,11 @@ static void seat_send_focus(struct sway_node *node, struct sway_seat *seat) {
 			wlr_seat_keyboard_notify_enter(
 					seat->wlr_seat, view->surface, NULL, 0, NULL);
 		}
+
+		struct wlr_pointer_constraint_v1 *constraint =
+			wlr_pointer_constraints_v1_constraint_for_surface(
+				server.pointer_constraints, view->surface, seat->wlr_seat);
+		sway_cursor_constrain(seat->cursor, constraint);
 	}
 }
 
@@ -684,6 +689,7 @@ static void send_unfocus(struct sway_container *con, void *data) {
 
 // Unfocus the container and any children (eg. when leaving `focus parent`)
 static void seat_send_unfocus(struct sway_node *node, struct sway_seat *seat) {
+	sway_cursor_constrain(seat->cursor, NULL);
 	wlr_seat_keyboard_clear_focus(seat->wlr_seat);
 	if (node->type == N_WORKSPACE) {
 		workspace_for_each_container(node->sway_workspace, send_unfocus, seat);

sway/input/seatop_down.c

@@ -26,14 +26,19 @@ static void handle_motion(struct sway_seat *seat, uint32_t time_msec) {
 
 static void handle_finish(struct sway_seat *seat) {
 	struct seatop_down_event *e = seat->seatop_data;
+	struct sway_cursor *cursor = seat->cursor;
 	// Set the cursor's previous coords to the x/y at the start of the
 	// operation, so the container change will be detected if using
 	// focus_follows_mouse and the cursor moved off the original container
 	// during the operation.
-	seat->cursor->previous.x = e->ref_lx;
-	seat->cursor->previous.y = e->ref_ly;
+	cursor->previous.x = e->ref_lx;
+	cursor->previous.y = e->ref_ly;
 	if (e->moved) {
-		cursor_send_pointer_motion(seat->cursor, 0);
+		struct wlr_surface *surface = NULL;
+		double sx, sy;
+		struct sway_node *node = node_at_coords(seat,
+				cursor->cursor->x, cursor->cursor->y, &surface, &sx, &sy);
+		cursor_send_pointer_motion(cursor, 0, node, surface, sx, sy);
 	}
 }
 

sway/server.c

@@ -10,11 +10,12 @@
 #include <wlr/types/wlr_compositor.h>
 #include <wlr/types/wlr_data_control_v1.h>
 #include <wlr/types/wlr_export_dmabuf_v1.h>
-#include <wlr/types/wlr_gamma_control_v1.h>
 #include <wlr/types/wlr_gamma_control.h>
+#include <wlr/types/wlr_gamma_control_v1.h>
 #include <wlr/types/wlr_gtk_primary_selection.h>
 #include <wlr/types/wlr_idle.h>
 #include <wlr/types/wlr_layer_shell_v1.h>
+#include <wlr/types/wlr_pointer_constraints_v1.h>
 #include <wlr/types/wlr_screencopy_v1.h>
 #include <wlr/types/wlr_server_decoration.h>
 #include <wlr/types/wlr_xcursor_manager.h>
@@ -105,6 +106,12 @@ bool server_init(struct sway_server *server) {
 	server->xdg_decoration.notify = handle_xdg_decoration;
 	wl_list_init(&server->xdg_decorations);
 
+	server->pointer_constraints =
+		wlr_pointer_constraints_v1_create(server->wl_display);
+	server->pointer_constraint.notify = handle_pointer_constraint;
+	wl_signal_add(&server->pointer_constraints->events.new_constraint,
+		&server->pointer_constraint);
+
 	server->presentation =
 		wlr_presentation_create(server->wl_display, server->backend);