(defn up!
  [screen x-val y-val z-val]
  (let [^Camera camera (u/get-obj screen :camera)
        ^Vector3 up-vec (up screen)]
    (some->> x-val (x! up-vec))
    (some->> y-val (y! up-vec))
    (some->> z-val (z! up-vec))
    (.update camera)))