Function ncplane_center_abs 

pub unsafe extern "C" fn ncplane_center_abs(
    n: *const ncplane,
    y: *mut c_int,
    x: *mut c_int,
)

Find the center coordinate of a plane, preferring the top/left in the case of an even number of rows/columns (in such a case, there will be one more cell to the bottom/right of the center than the top/left). The center is then modified relative to the plane’s origin.