simple game loop that reads regular ajax results and also updates on every animation frame

game-loop.cljs

(defn game-loop []
  (let [anim-chan (au/anim-ch active)
        ajax-chan (au/ajax-loop "world" slowth active)]
    (go
     (loop [state {:world {} :timestamp (js-now)}]
       (when @active
         (let [next-state
                 (alt!
                    anim-chan ([val] (do
                                       (graphics/draw-map
                                          ctx (:world state) (scaled-time val (:timestamp state)))
                                       state)) ; no state change
                    ajax-chan ([val] {:world val :timestamp (js-now)}))]
           (recur next-state)))))))