Event.GestureGestures (e.g. pinch-to-zoom on a touchpad).
type ty = [ | `Gesture_swipe_begin of [ `Gesture_swipe_begin ] t| `Gesture_swipe_update of [ `Gesture_swipe_update ] t| `Gesture_swipe_end of [ `Gesture_swipe_end ] t| `Gesture_pinch_begin of [ `Gesture_pinch_begin ] t| `Gesture_pinch_update of [ `Gesture_pinch_update ] t| `Gesture_pinch_end of [ `Gesture_pinch_end ] t| `Gesture_hold_begin of [ `Gesture_hold_begin ] t| `Gesture_hold_end of [ `Gesture_hold_end ] t ]val get_time : [< any ] t -> Timestamp.tval get_cancelled : [< `Gesture_swipe_end | `Gesture_pinch_end ] t -> boolval get_dx : [< `Gesture_swipe_update | `Gesture_pinch_update ] t -> floatval get_dy : [< `Gesture_swipe_update | `Gesture_pinch_update ] t -> floatval get_dx_unaccelerated :
[< `Gesture_swipe_update | `Gesture_pinch_update ] t ->
floatval get_dy_unaccelerated :
[< `Gesture_swipe_update | `Gesture_pinch_update ] t ->
floatval get_scale :
[< `Gesture_pinch_begin | `Gesture_pinch_update | `Gesture_pinch_end ] t ->
floatval get_angle_delta : [ `Gesture_pinch_update ] t -> float