overtone-1.clj

(ns test.core
  (:use [overtone.live]
        [overtone.inst.synth]))

(def kick  (sample "kick.wav"))
(def snare (sample "snare.wav"))
(def hit   (sample "hit.wav"))
(def insts {:kick  kick
            :snare snare
            :hit   hit})
(def pat {:kick  [1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0]
          :snare [0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0]
          :hit   [0 0 1 0 0 0 0 0 0 1 0 0 0 1 0 0]})

(def metro (metronome 135))

(defn play-pat [beat i]
  (let [t (mod beat 4)
        p (vec (take 4 (drop (* 4 t) (pat i))))]
    (if (= 1 (p 0)) (at (metro (+ 0.00 beat)) ((insts i))))
    (if (= 1 (p 1)) (at (metro (+ 0.25 beat)) ((insts i))))
    (if (= 1 (p 2)) (at (metro (+ 0.50 beat)) ((insts i))))
    (if (= 1 (p 3)) (at (metro (+ 0.75 beat)) ((insts i))))))

(defn player [beat]
  (doseq [i (keys insts)] (play-pat beat i))
  (apply-at (metro (inc beat)) #'player (inc beat) []))

(player (metro))

(metro :bpm 160)
(metro :bpm 90)

(defn player [beat] "stop")