[][src]Function input_sys::libinput_event_tablet_pad_get_ring_position

pub unsafe extern "C" fn libinput_event_tablet_pad_get_ring_position(
    event: *mut libinput_event_tablet_pad
) -> f64

@ingroup event_tablet_pad

Returns the current position of the ring, in degrees counterclockwise from the northern-most point of the ring in the tablet's current logical orientation.

If the source is @ref LIBINPUT_TABLET_PAD_RING_SOURCE_FINGER, libinput sends a terminating event with a ring value of -1 when the finger is lifted from the ring. A caller may use this information to e.g. determine if kinetic scrolling should be triggered.

@note It is an application bug to call this function for events other than @ref LIBINPUT_EVENT_TABLET_PAD_RING. For other events, this function returns 0.

@param event The libinput tablet pad event @return The current value of the the axis @retval -1 The finger was lifted

@since 1.3