View difference between Paste ID: 1GFqvxj6 and BtMsDdev

 (defn quad-tree
   ([c l] {:mid c :len l})
   ([c l v] (assoc (quad-tree c l) :value v)))
 
 (defn next-mid
   [qt quad]
   (let [[x y] (:mid qt)
         d (/ (:len qt) 2)]
     (case quad
       :I   [(+ x d) (+ y d)]
       :II  [(- x d) (+ y d)]
       :III [(- x d) (- y d)]
       :IV  [(+ x d) (- y d)]
       :else (println "Invalid quadrant"))))
 
 (defn next-quad [[x y] [px py]]
   (cond
    (and (> px x) (> py y)) :I
    (and (< px x) (> py y)) :II
    (and (< px x) (< py y)) :III
    (and (> px x) (< py y)) :IV))
 
 (declare add-points)
 
 (defn add-point
   [qt point]
   (let [[x y] (:mid qt)
         [px py] point
         quad (next-quad [x y] point)
         val (:value qt)
         loc (quad qt)]
     (cond
      val (-> qt (dissoc :value) (add-points [val point]))
      loc (assoc qt quad (add-point loc point))
      :else (assoc qt quad (quad-tree (next-mid qt quad) (/ (:len qt) 2) point)))))
 
 (defn add-points
   [qt pts] (reduce add-point qt pts))