face.clj

(defrecord Face [vertices normal]
  IHashEq
  (hasheq [this] (bit-xor (.hasheq (.vertices this))
                          (.GetHashCode (.normal this))))
  
  Object
  (ToString [this] (str "#Face[" (.normal this) " " (.vertices this) "]"))
  
  IPersistentCollection
  (count [this] (count (.vertices this)))
  (clojure.lang.IPersistentCollection.cons
    [this o]
    (Face. (conj (.vertices this) o)
           (.normal this)))
  (empty [this] (Face. [] Vector3/zero))
  (equiv [this o]
         (and ; (isa? (type o) Face)
              (some? o)
              (some? this)
              (= (.vertices this) (.vertices o))
              (= (.normal this) (.normal o))))
  
  Counted
  (count [this] (count (.vertices this)))
  Indexed
  (nth [this i] (get (.vertices this) i))
  (nth [this i else] (get (.vertices this) i else))
  Seqable
  (seq [^Face this] (seq (.vertices this))))