sway: add bindgesture command

Co-authored-by: Michael Weiser <michael.weiser@gmx.de>

sway/input/seatop_default.c

@@ -4,6 +4,7 @@
 #include <wlr/types/wlr_cursor.h>
 #include <wlr/types/wlr_tablet_v2.h>
 #include <wlr/types/wlr_xcursor_manager.h>
+#include "gesture.h"
 #include "sway/desktop/transaction.h"
 #include "sway/input/cursor.h"
 #include "sway/input/seat.h"
@@ -20,6 +21,7 @@ struct seatop_default_event {
 	struct sway_node *previous_node;
 	uint32_t pressed_buttons[SWAY_CURSOR_PRESSED_BUTTONS_CAP];
 	size_t pressed_button_count;
+	struct gesture_tracker gestures;
 };
 
 /*-----------------------------------------\
@@ -750,6 +752,304 @@ static void handle_pointer_axis(struct sway_seat *seat,
 	}
 }
 
+/*------------------------------------\
+ * Functions used by gesture support  /
+ *----------------------------------*/
+
+/**
+ * Check gesture binding for a specific gesture type and finger count.
+ * Returns true if binding is present, false otherwise
+ */
+static bool gesture_binding_check(list_t *bindings, enum gesture_type type,
+		uint8_t fingers, struct sway_input_device *device) {
+	char *input =
+		device ? input_device_get_identifier(device->wlr_device) : strdup("*");
+
+	for (int i = 0; i < bindings->length; ++i) {
+		struct sway_gesture_binding *binding = bindings->items[i];
+
+		// Check type and finger count
+		if (!gesture_check(&binding->gesture, type, fingers)) {
+			continue;
+		}
+
+		// Check that input matches
+		if (strcmp(binding->input, "*") != 0 &&
+			strcmp(binding->input, input) != 0) {
+			continue;
+		}
+
+		free(input);
+
+		return true;
+	}
+
+	free(input);
+
+	return false;
+}
+
+/**
+ * Return the gesture binding which matches gesture type, finger count
+ * and direction, otherwise return null.
+ */
+static struct sway_gesture_binding* gesture_binding_match(
+		list_t *bindings, struct gesture *gesture, const char *input) {
+	struct sway_gesture_binding *current = NULL;
+
+	// Find best matching binding
+	for (int i = 0; i < bindings->length; ++i) {
+		struct sway_gesture_binding *binding = bindings->items[i];
+		bool exact = binding->flags & BINDING_EXACT;
+
+		// Check gesture matching
+		if (!gesture_match(&binding->gesture, gesture, exact)) {
+			continue;
+		}
+
+		// Check input matching
+		if (strcmp(binding->input, "*") != 0 &&
+				strcmp(binding->input, input) != 0) {
+			continue;
+		}
+
+		// If we already have a match ...
+		if (current) {
+			// ... check if input matching is equivalent
+			if (strcmp(current->input, binding->input) == 0) {
+
+				// ... - do not override an exact binding
+				if (!exact && current->flags & BINDING_EXACT) {
+					continue;
+				}
+
+				// ... - and ensure direction matching is better or equal
+				if (gesture_compare(&current->gesture, &binding->gesture) > 0) {
+					continue;
+				}
+			} else if (strcmp(binding->input, "*") == 0) {
+				// ... do not accept worse input match
+				continue;
+			}
+		}
+
+		// Accept newer or better match
+		current = binding;
+
+		// If exact binding and input is found, quit search
+		if (strcmp(current->input, input) == 0 &&
+				gesture_compare(&current->gesture, gesture) == 0) {
+			break;
+		}
+	} // for all gesture bindings
+
+	return current;
+}
+
+// Wrapper around gesture_tracker_end to use tracker with sway bindings
+static struct sway_gesture_binding* gesture_tracker_end_and_match(
+		struct gesture_tracker *tracker, struct sway_input_device* device) {
+	// Determine name of input that received gesture
+	char *input = device
+		? input_device_get_identifier(device->wlr_device)
+		: strdup("*");
+
+	// Match tracking result to binding
+	struct gesture *gesture = gesture_tracker_end(tracker);
+	struct sway_gesture_binding *binding = gesture_binding_match(
+			config->current_mode->gesture_bindings, gesture, input);
+	free(gesture);
+	free(input);
+
+	return binding;
+}
+
+// Small wrapper around seat_execute_command to work on gesture bindings
+static void gesture_binding_execute(struct sway_seat *seat,
+		struct sway_gesture_binding *binding) {
+	struct sway_binding *dummy_binding =
+		calloc(1, sizeof(struct sway_binding));
+	dummy_binding->type = BINDING_GESTURE;
+	dummy_binding->command = binding->command;
+
+	char *description = gesture_to_string(&binding->gesture);
+	sway_log(SWAY_DEBUG, "executing gesture binding: %s", description);
+	free(description);
+
+	seat_execute_command(seat, dummy_binding);
+
+	free(dummy_binding);
+}
+
+static void handle_hold_begin(struct sway_seat *seat,
+		struct wlr_pointer_hold_begin_event *event) {
+	// Start tracking gesture if there is a matching binding ...
+	struct sway_input_device *device =
+		event->pointer ? event->pointer->base.data : NULL;
+	list_t *bindings = config->current_mode->gesture_bindings;
+	if (gesture_binding_check(bindings, GESTURE_TYPE_HOLD, event->fingers, device)) {
+		struct seatop_default_event *seatop = seat->seatop_data;
+		gesture_tracker_begin(&seatop->gestures, GESTURE_TYPE_HOLD, event->fingers);
+	} else {
+		// ... otherwise forward to client
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_hold_begin(
+			cursor->pointer_gestures, cursor->seat->wlr_seat,
+			event->time_msec, event->fingers);
+	}
+}
+
+static void handle_hold_end(struct sway_seat *seat,
+		struct wlr_pointer_hold_end_event *event) {
+	// Ensure that gesture is being tracked and was not cancelled
+	struct seatop_default_event *seatop = seat->seatop_data;
+	if (!gesture_tracker_check(&seatop->gestures, GESTURE_TYPE_HOLD)) {
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_hold_end(
+			cursor->pointer_gestures, cursor->seat->wlr_seat,
+			event->time_msec, event->cancelled);
+		return;
+	}
+	if (event->cancelled) {
+		gesture_tracker_cancel(&seatop->gestures);
+		return;
+	}
+
+	// End gesture tracking and execute matched binding
+	struct sway_input_device *device =
+		event->pointer ? event->pointer->base.data : NULL;
+	struct sway_gesture_binding *binding = gesture_tracker_end_and_match(
+		&seatop->gestures, device);
+
+	if (binding) {
+		gesture_binding_execute(seat, binding);
+	}
+}
+
+static void handle_pinch_begin(struct sway_seat *seat,
+		struct wlr_pointer_pinch_begin_event *event) {
+	// Start tracking gesture if there is a matching binding ...
+	struct sway_input_device *device =
+		event->pointer ? event->pointer->base.data : NULL;
+	list_t *bindings = config->current_mode->gesture_bindings;
+	if (gesture_binding_check(bindings, GESTURE_TYPE_PINCH, event->fingers, device)) {
+		struct seatop_default_event *seatop = seat->seatop_data;
+		gesture_tracker_begin(&seatop->gestures, GESTURE_TYPE_PINCH, event->fingers);
+	} else {
+		// ... otherwise forward to client
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_pinch_begin(
+			cursor->pointer_gestures, cursor->seat->wlr_seat,
+			event->time_msec, event->fingers);
+	}
+}
+
+static void handle_pinch_update(struct sway_seat *seat,
+		struct wlr_pointer_pinch_update_event *event) {
+	// Update any ongoing tracking ...
+	struct seatop_default_event *seatop = seat->seatop_data;
+	if (gesture_tracker_check(&seatop->gestures, GESTURE_TYPE_PINCH)) {
+		gesture_tracker_update(&seatop->gestures, event->dx, event->dy,
+			event->scale, event->rotation);
+	} else {
+		// ... otherwise forward to client
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_pinch_update(
+			cursor->pointer_gestures,
+			cursor->seat->wlr_seat,
+			event->time_msec, event->dx, event->dy,
+			event->scale, event->rotation);
+	}
+}
+
+static void handle_pinch_end(struct sway_seat *seat,
+		struct wlr_pointer_pinch_end_event *event) {
+	// Ensure that gesture is being tracked and was not cancelled
+	struct seatop_default_event *seatop = seat->seatop_data;
+	if (!gesture_tracker_check(&seatop->gestures, GESTURE_TYPE_PINCH)) {
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_pinch_end(
+			cursor->pointer_gestures, cursor->seat->wlr_seat,
+			event->time_msec, event->cancelled);
+		return;
+	}
+	if (event->cancelled) {
+		gesture_tracker_cancel(&seatop->gestures);
+		return;
+	}
+
+	// End gesture tracking and execute matched binding
+	struct sway_input_device *device =
+		event->pointer ? event->pointer->base.data : NULL;
+	struct sway_gesture_binding *binding = gesture_tracker_end_and_match(
+		&seatop->gestures, device);
+
+	if (binding) {
+		gesture_binding_execute(seat, binding);
+	}
+}
+
+static void handle_swipe_begin(struct sway_seat *seat,
+		struct wlr_pointer_swipe_begin_event *event) {
+	// Start tracking gesture if there is a matching binding ...
+	struct sway_input_device *device =
+		event->pointer ? event->pointer->base.data : NULL;
+	list_t *bindings = config->current_mode->gesture_bindings;
+	if (gesture_binding_check(bindings, GESTURE_TYPE_SWIPE, event->fingers, device)) {
+		struct seatop_default_event *seatop = seat->seatop_data;
+		gesture_tracker_begin(&seatop->gestures, GESTURE_TYPE_SWIPE, event->fingers);
+	} else {
+		// ... otherwise forward to client
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_swipe_begin(
+			cursor->pointer_gestures, cursor->seat->wlr_seat,
+			event->time_msec, event->fingers);
+	}
+}
+
+static void handle_swipe_update(struct sway_seat *seat,
+		struct wlr_pointer_swipe_update_event *event) {
+
+	// Update any ongoing tracking ...
+	struct seatop_default_event *seatop = seat->seatop_data;
+	if (gesture_tracker_check(&seatop->gestures, GESTURE_TYPE_SWIPE)) {
+		gesture_tracker_update(&seatop->gestures,
+			event->dx, event->dy, NAN, NAN);
+	} else {
+		// ... otherwise forward to client
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_swipe_update(
+			cursor->pointer_gestures, cursor->seat->wlr_seat,
+			event->time_msec, event->dx, event->dy);
+	}
+}
+
+static void handle_swipe_end(struct sway_seat *seat,
+		struct wlr_pointer_swipe_end_event *event) {
+	// Ensure gesture is being tracked and was not cancelled
+	struct seatop_default_event *seatop = seat->seatop_data;
+	if (!gesture_tracker_check(&seatop->gestures, GESTURE_TYPE_SWIPE)) {
+		struct sway_cursor *cursor = seat->cursor;
+		wlr_pointer_gestures_v1_send_swipe_end(cursor->pointer_gestures,
+			cursor->seat->wlr_seat, event->time_msec, event->cancelled);
+		return;
+	}
+	if (event->cancelled) {
+		gesture_tracker_cancel(&seatop->gestures);
+		return;
+	}
+
+	// End gesture tracking and execute matched binding
+	struct sway_input_device *device =
+		event->pointer ? event->pointer->base.data : NULL;
+	struct sway_gesture_binding *binding = gesture_tracker_end_and_match(
+		&seatop->gestures, device);
+
+	if (binding) {
+		gesture_binding_execute(seat, binding);
+	}
+}
+
 /*----------------------------------\
  * Functions used by handle_rebase  /
  *--------------------------------*/
@@ -779,6 +1079,14 @@ static const struct sway_seatop_impl seatop_impl = {
 	.pointer_axis = handle_pointer_axis,
 	.tablet_tool_tip = handle_tablet_tool_tip,
 	.tablet_tool_motion = handle_tablet_tool_motion,
+	.hold_begin = handle_hold_begin,
+	.hold_end = handle_hold_end,
+	.pinch_begin = handle_pinch_begin,
+	.pinch_update = handle_pinch_update,
+	.pinch_end = handle_pinch_end,
+	.swipe_begin = handle_swipe_begin,
+	.swipe_update = handle_swipe_update,
+	.swipe_end = handle_swipe_end,
 	.rebase = handle_rebase,
 	.allow_set_cursor = true,
 };
@@ -789,8 +1097,8 @@ void seatop_begin_default(struct sway_seat *seat) {
 	struct seatop_default_event *e =
 		calloc(1, sizeof(struct seatop_default_event));
 	sway_assert(e, "Unable to allocate seatop_default_event");
+
 	seat->seatop_impl = &seatop_impl;
 	seat->seatop_data = e;
-
 	seatop_rebase(seat, 0);
 }