let index = [];

let indexed_sequence = [];

​

let markov = []; //this will be an array of arrays

let index_size;

let durations = [];

​

let position;

let haveTriggered = false;

​

let drumNames = ["kick", "snare", "hh", "hho"];

let kit = new Tone.Players({

              "kick" : "/samples/kick.mp3",

              "snare" : "/samples/snare.mp3",

                "hh" : "/samples/hh.mp3",

                "hho" : "/samples/hho.mp3"

    }).toMaster();

​

​

function setup() {

  index_size = 0;

  //process sequence

  let new_item = true;

  //step 1: analyze sequence

  for(let i =0; i < sequence.length; i++){

    new_item = true;

    //check if item is new. if not, point to existing index

    for(let j = 0; j < index_size; j++){

      if(sequence[i] == index[j]){

        new_item = false;

        indexed_sequence[i] = j;

      }

    }

    if(new_item){

      index[index_size] = sequence[i];

      indexed_sequence[i] = index_size;

      index_size++;

    }

  }

  console.log("raw sequence: "+ sequence);

  console.log("index: " + index);

  console.log("indexed sequence: " + indexed_sequence);

  //step 2: create transition matrix

  //create table

  for(let i = 0; i < index_size; i++){

    markov[i] = [];

  }

  for(var i = 0; i < indexed_sequence.length; i++){ //for each unique pitch

    let current = indexed_sequence[i];

    let next_pos = (i + 1) % indexed_sequence.length;

    let next = indexed_sequence[next_pos];

    markov[current].push(next);

  }

  //print transition table

  for(let i = 0; i < markov.length; i++){

    console.log(markov[i]);

  }

  //step 3: create rhythm

  var rhythmLength = 100;

  var currentIndex = parseInt(random(0, markov.length)); //start anywhere

  for(let i = 0; i < rhythmLength; i++){

    var transitionPos = parseInt(random(0, markov[currentIndex].length));

    var nextIndex = markov[currentIndex][transitionPos];

    currentIndex = nextIndex;

    durations.push(index[currentIndex]);

  }

  console.log("generated rhythm: " + durations);

  position = 0;

  //play back melody

  //create "score"

  let part = [];

  for(let i = 0; i < durations.length; i++){

    let duration = Tone.Time(durations[i]).toSeconds();

    let event = {"time": position, "sample": drumNames[floor(random()*4)], "velocity": random(), "duration": duration}; //add duration

    part.push(event);

    position = position + duration;

    console.log(position);

    //TODO: replace all "pitches" by "duration"

  }

  var newPart = new Tone.Part(function(time, value){

    kit.get(value.sample).start(time, 0, value.duration, 0, 1);

  }, part).start(0);

}

​

function draw() {

  if(kit.loaded && !haveTriggered){

    Tone.Transport.start();

    haveTriggered = true;

  }

}

​