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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <div class="container">
  <div class="machine-bg">
    <div class="player"></div>
    <div class="controls top-controls">
      <div>
        <div id="temperature" class="mdc-slider" tabindex="0" role="slider" aria-valuemin="0.2" aria-valuemax="2" aria-valuenow="1.1"
             aria-label="Select temperature">
          <div class="mdc-slider__track-container">
            <div class="mdc-slider__track"></div>
          </div>
          <div class="mdc-slider__thumb-container">
            <svg class="mdc-slider__thumb" width="21" height="21">
              <circle cx="10.5" cy="10.5" r="7.875"></circle>
            </svg>
            <div class="mdc-slider__focus-ring"></div>
          </div>
        </div>
        Temperature
      </div>
      <div>
        <div class="mdc-select">
          <select id="pattern-length" class="mdc-select__native-control" role="presentation">
            <option>4</option>
            <option selected>8</option>
            <option>16</option>
            <option>32</option>
          </select>
          <div class="mdc-select__bottom-line"></div>
        </div>
        Pattern length
      </div>
      <div>
        <div class="mdc-switch">
          <div class="mdc-switch__track"></div>
          <div class="mdc-switch__thumb-underlay">
            <div class="mdc-switch__thumb">
              <input type="checkbox" id="pulse-switch" class="mdc-switch__native-control" role="switch" checked>
            </div>
          </div>
        </div>
        <label for="pulse-switch">steady pulse</label>
      </div>
    </div>
  </div>
  <div class="human-bg">
    <div class="player"></div>
    <div class="controls">
      <div class="midi-not-supported">
        Press and hold a note or chord using the
        <a href="https://camo.githubusercontent.com/29529110d639ed79a04752c036fe301fd15c961b/68747470733a2f2f7261772e6769746875622e636f6d2f6b796c65737465747a2f617564696f6b6579732f6d61737465722f696d616765732f617564696f6b6579732d6d617070696e672d726f7773322e6a7067"
           target="_blank">computer keyboard</a>, or with a MIDI controller on
        <a href="https://caniuse.com/#feat=midi" target="_blank">a MIDI capable web browser</a>.</div>
      <div class="midi-supported-no-inputs" style="display: none">
        Press and hold a note or chord using a MIDI controller or
        <a href="https://camo.githubusercontent.com/29529110d639ed79a04752c036fe301fd15c961b/68747470733a2f2f7261772e6769746875622e636f6d2f6b796c65737465747a2f617564696f6b6579732f6d61737465722f696d616765732f617564696f6b6579732d6d617070696e672d726f7773322e6a7067"
           target="_blank">computer keyboard</a>.</div>
      <div class="midi-supported-with-inputs" style="display: none">
        <p>
          Press and hold a note or chord using  <a href="https://camo.githubusercontent.com/29529110d639ed79a04752c036fe301fd15c961b/68747470733a2f2f7261772e6769746875622e636f6d2f6b796c65737465747a2f617564696f6b6579732f6d61737465722f696d616765732f617564696f6b6579732d6d617070696e672d726f7773322e6a7067"
                                                   target="_blank">computer keyboard</a> or choose a MIDI controller from below.
        </p>
        <div>
          MIDI input
          <div class="mdc-select">
            <select id="midi-inputs" class="mdc-select__native-control" role="presentation"></select>
            <div class="mdc-select__bottom-line"></div>
          </div>
          Clock input 
          <div class="mdc-select">
            <select id="midi-clock-inputs" class="mdc-select__native-control" role="presentation"></select>
            <div class="mdc-select__bottom-line"></div>
          </div>
        </div>
        <div>
          Output
          <div class="mdc-select">
            <select id="outputs" class="mdc-select__native-control" role="presentation"></select>
            <div class="mdc-select__bottom-line"></div>
          </div>
          Clock Output
          <div class="mdc-select">
            <select id="midi-clock-outputs" class="mdc-select__native-control" role="presentation"></select>
            <div class="mdc-select__bottom-line"></div>
          </div>
        </div>

      </div>
      <p>A
        <a href="https://github.com/tensorflow/magenta/tree/master/magenta/models/improv_rnn" target="_blank">neural network</a> will arpeggiate around your chord.</p>
      <p>Using the
        <a href="https://github.com/tensorflow/magenta/tree/master/magenta/models/improv_rnn">Improv RNN</a> (pretrained) model from
        <a href="https://magenta.tensorflow.org/">Google Magenta</a>, and
        <a href="https://goo.gl/magenta/js">Magenta.js</a> + 
        <a href="https://js.tensorflow.org/">TensorFlow.js</a> +
        <a href="https://tonejs.github.io/">Tone.js</a>.</p>
    </div>
  </div>
  <div class="keyboard">
  </div>
  <div class="loading">
    Loading...
  </div>
</div>
            
          
!
            
              body,
html {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
}

.container {
  width: 100%;
  height: 100%;
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;

  color: white;
  font-family: 'Abel', sans-serif;
}
a,
a:visited {
  color: white;
}

.machine-bg {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 50%;
  background: linear-gradient(to right, #000000, #323232);

  display: flex;
  justify-content: center;
  align-items: center;
}
.human-bg {
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 50%;
  background: linear-gradient(to left, #000000, #323232);

  display: flex;
  justify-content: center;
  align-items: center;
}

.controls {
  z-index: 4;
  font-size: 16px;
  text-align: center;
  transition: opacity 0.5s ease-out;
  opacity: 1;
}
.top-controls {
  display: flex;
  justify-content: space-around;
  width: 500px;
}
.mdc-select,
.mdc-select__native-control {
  color: white !important; /* Whatever. */
  border-bottom-color: white !important;
  margin: 0 5px;
  padding-top: 5px;
}
.ui-hidden .controls {
  opacity: 0;
}
.machine-bg .controls {
  margin-bottom: 125px;
}
.top-controls .mdc-slider {
  margin-bottom: 5px;
}
.top-controls .mdc-select {
  display: block;
}
.top-controls .mdc-switch {
  display: block;
  margin-top: 20px;
  margin-bottom: 16px;
}
.controls #temperature {
  width: 200px;
}
.human-bg .controls {
  margin-top: 125px;
}

.machine-bg .player,
.human-bg .player {
  position: absolute;
  left: 5vw;
  width: 90vw;
  top: 0;
  bottom: 0;
}
.machine-bg .player .key,
.human-bg .player .key {
  position: absolute;
  top: 0;
  height: 100%;
}
.machine-bg .player .key {
  background-color: #e91e63;
  opacity: 0;
}
.human-bg .player .key.down {
  background-color: #64b5f6;
  opacity: 0.9;
}

.keyboard {
  position: absolute;
  left: 5vw;
  width: 90vw;
  top: calc(50% - 125px);
  height: 250px;
  opacity: 0;
  transition: opacity 0.7s ease-in;
}
.keyboard.loaded {
  opacity: 1;
}

.keyboard .key {
  position: absolute;
  top: 0;
  height: 100%;
  box-sizing: border-box;
  z-index: 1;
  background-color: white;
  box-shadow: 0 0 5px #333;
  border-radius: 3px;
}

.keyboard .key.accidental {
  height: 170px;
  z-index: 2;
  background-color: black;
  box-shadow: none;
  border-width: 0;
  border-top-left-radius: 0;
  border-top-right-radius: 0;
}

.loading {
  position: absolute;
  left: 0;
  width: 100%;
  top: calc(50% - 30px);
  height: 250px;
  text-align: centeR;

  color: white;
  font-size: 40px;
}

            
          
!
            
              const MIN_NOTE = 48;
const MAX_NOTE = 84;
const DEFAULT_BPM = 120;
const MAX_MIDI_BPM = 240;
const TEMPO_MIDI_CONTROLLER = 20; // Control changes for tempo for this controller id

let Tone = mm.Player.tone;

let temperature = 1.1;
let patternLength = 8;

// Using the Improv RNN pretrained model from https://github.com/tensorflow/magenta/tree/master/magenta/models/improv_rnn
let rnn = new mm.MusicRNN(
  'https://storage.googleapis.com/download.magenta.tensorflow.org/tfjs_checkpoints/music_rnn/chord_pitches_improv'
);

let masterGain = new Tone.Gain(0.6).toMaster();
let reverb = new Tone.Convolver(
  'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/hm2_000_ortf_48k.mp3'
).connect(masterGain);
reverb.wet.value = 0.1;
let echo = new Tone.FeedbackDelay('8n.', 0.4).connect(
  new Tone.Gain(0.5).connect(reverb)
);
let lowPass = new Tone.Filter(5000).connect(echo).connect(reverb);
new Tone.LFO('8m', 3000, 5000).connect(lowPass.frequency).start();
let sampler = new Tone.Sampler({
  C3: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-c3.wav',
  'D#3': 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-ds3.wav',
  'F#3': 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-fs3.wav',
  A3: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-a3.wav',
  C4: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-c4.wav',
  'D#4': 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-ds4.wav',
  'F#4': 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-fs4.wav',
  A4: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-a4.wav',
  C5: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-c5.wav',
  'D#5': 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-ds5.wav',
  'F#5': 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-fs5.wav',
  A5: 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699/s11-a5.wav'
}).connect(lowPass);
sampler.release.value = 2;

let builtInKeyboard = new AudioKeys({ rows: 2 });
let onScreenKeyboardContainer = document.querySelector('.keyboard');
let onScreenKeyboard = buildKeyboard(onScreenKeyboardContainer);
let machinePlayer = buildKeyboard(
  document.querySelector('.machine-bg .player')
);
let humanPlayer = buildKeyboard(document.querySelector('.human-bg .player'));

let currentSeed = [];
let stopCurrentSequenceGenerator;
let synthFilter = new Tone.Filter(300, 'lowpass').connect(
  new Tone.Gain(0.4).connect(masterGain)
);
let synthConfig = {
  oscillator: { type: 'fattriangle' },
  envelope: { attack: 3, sustain: 1, release: 1 }
};
let pulsePattern = true;
let synthsPlaying = {};
let currentPlayFn;
let tick = 0;

let outputs = {
  internal: {
    play: (note, velocity, time, hold = false) => {
      let freq = Tone.Frequency(note, 'midi');
      if (hold) {
        if (!synthsPlaying[note]) {
          let synth = new Tone.Synth(synthConfig).connect(synthFilter);
          synthsPlaying[note] = synth;
          synth.triggerAttack(freq, time, velocity);
        }
      } else {
        sampler.triggerAttack(freq, time);
      }
    },
    stop: (note, time) => {
      if (synthsPlaying[note]) {
        let synth = synthsPlaying[note];
        synth.triggerRelease(time);
        setTimeout(() => synth.dispose(), 2000);
        synthsPlaying[note] = null;
      }
    }
  }
};
let activeOutput = 'internal';

function isAccidental(note) {
  let pc = note % 12;
  return pc === 1 || pc === 3 || pc === 6 || pc === 8 || pc === 10;
}

function buildKeyboard(container) {
  let nAccidentals = _.range(MIN_NOTE, MAX_NOTE + 1).filter(isAccidental)
    .length;
  let keyWidthPercent = 100 / (MAX_NOTE - MIN_NOTE - nAccidentals + 1);
  let keyInnerWidthPercent =
    100 / (MAX_NOTE - MIN_NOTE - nAccidentals + 1) - 0.5;
  let gapPercent = keyWidthPercent - keyInnerWidthPercent;
  let accumulatedWidth = 0;
  return _.range(MIN_NOTE, MAX_NOTE + 1).map(note => {
    let accidental = isAccidental(note);
    let key = document.createElement('div');
    key.classList.add('key');
    if (accidental) {
      key.classList.add('accidental');
      key.style.left = `${accumulatedWidth -
        gapPercent -
        (keyWidthPercent / 2 - gapPercent) / 2}%`;
      key.style.width = `${keyWidthPercent / 2}%`;
    } else {
      key.style.left = `${accumulatedWidth}%`;
      key.style.width = `${keyInnerWidthPercent}%`;
    }
    container.appendChild(key);
    if (!accidental) accumulatedWidth += keyWidthPercent;
    return key;
  });
}

function detectChord(notes) {
  notes = notes.map(n => Tonal.Note.pc(Tonal.Note.fromMidi(n.note))).sort();
  return Tonal.PcSet.modes(notes)
    .map((mode, i) => {
      const tonic = Tonal.Note.name(notes[i]);
      const names = Tonal.Dictionary.chord.names(mode);
      return names.length ? tonic + names[0] : null;
    })
    .filter(x => x);
}

function buildNoteSequence(seed) {
  let step = 0;
  let delayProb = pulsePattern ? 0 : 0.3;
  let notes = seed.map(n => {
    let dur = 1 + (Math.random() < delayProb ? 1 : 0);
    let note = {
      pitch: n.note,
      quantizedStartStep: step,
      quantizedEndStep: step + dur
    };
    step += dur;
    return note;
  });
  return {
    totalQuantizedSteps: _.last(notes).quantizedEndStep,
    quantizationInfo: {
      stepsPerQuarter: 1
    },
    notes
  };
}

function seqToTickArray(seq) {
  return _.flatMap(seq.notes, n =>
    [n.pitch].concat(
      pulsePattern
        ? []
        : _.times(n.quantizedEndStep - n.quantizedStartStep - 1, () => null)
    )
  );
}

function doTick(time = Tone.now() - Tone.context.lookAhead) {
  applyHumanKeyChanges(time);
  if (currentPlayFn) currentPlayFn(time);
}

function startSequenceGenerator(seed) {
  let running = true,
    thisPatternLength = patternLength;

  let chords = detectChord(seed);
  let chord =
    _.first(chords) ||
    Tonal.Note.pc(Tonal.Note.fromMidi(_.first(seed).note)) + 'M';
  let seedSeq = buildNoteSequence(seed);
  let generatedSequence = seqToTickArray(seedSeq);
  let playIntervalTime = Tone.Time('8n').toSeconds();
  let generationIntervalTime = playIntervalTime / 2;
  function generateNext() {
    if (!running) return;
    if (generatedSequence.length < thisPatternLength) {
      rnn.continueSequence(seedSeq, 20, temperature, [chord]).then(genSeq => {
        generatedSequence = generatedSequence.concat(seqToTickArray(genSeq));
        setTimeout(generateNext, generationIntervalTime * 1000);
      });
    }
  }

  tick = 0;
  currentPlayFn = function playNext(time) {
    let tickInSeq = tick % thisPatternLength;
    if (tickInSeq < generatedSequence.length) {
      let note = generatedSequence[tickInSeq];
      if (note) machineKeyDown(note, time);
    }
    tick++;
  };

  setTimeout(generateNext, 0);

  return () => {
    running = false;
    currentPlayFn = null;
  };
}

function updateChord({ add = [], remove = [] }) {
  for (let note of add) {
    currentSeed.push({ note, time: Tone.now() });
  }
  for (let note of remove) {
    _.remove(currentSeed, { note });
  }

  if (stopCurrentSequenceGenerator) {
    stopCurrentSequenceGenerator();
    stopCurrentSequenceGenerator = null;
  }
  if (currentSeed.length) {
    stopCurrentSequenceGenerator = startSequenceGenerator(
      _.cloneDeep(currentSeed)
    );
  }
}

let humanKeyAdds = [],
  humanKeyRemovals = [];
function humanKeyDown(note, velocity = 0.7) {
  if (note < MIN_NOTE || note > MAX_NOTE) return;
  humanKeyAdds.push({ note, velocity });
}
function humanKeyUp(note) {
  if (note < MIN_NOTE || note > MAX_NOTE) return;
  humanKeyRemovals.push({ note });
}
function applyHumanKeyChanges(time = Tone.now()) {
  if (humanKeyAdds.length == 0 && humanKeyRemovals.length == 0) return;
  for (let { note, velocity } of humanKeyAdds) {
    outputs[activeOutput].play(note, velocity, time, true);
    humanPlayer[note - MIN_NOTE].classList.add('down');
    animatePlay(onScreenKeyboard[note - MIN_NOTE], note, true);
  }
  for (let { note } of humanKeyRemovals) {
    outputs[activeOutput].stop(note, time);
    humanPlayer[note - MIN_NOTE].classList.remove('down');
  }
  updateChord({
    add: humanKeyAdds.map(n => n.note),
    remove: humanKeyRemovals.map(n => n.note)
  });
  humanKeyAdds.length = 0;
  humanKeyRemovals.length = 0;
}

function machineKeyDown(note, time) {
  if (note < MIN_NOTE || note > MAX_NOTE) return;
  outputs[activeOutput].play(note, 0.7, time);
  animatePlay(onScreenKeyboard[note - MIN_NOTE], note, false);
  animateMachine(machinePlayer[note - MIN_NOTE]);
}

function animatePlay(keyEl, note, isHuman) {
  let sourceColor = isHuman ? '#1E88E5' : '#E91E63';
  let targetColor = isAccidental(note) ? 'black' : 'white';
  keyEl.animate(
    [{ backgroundColor: sourceColor }, { backgroundColor: targetColor }],
    { duration: 700, easing: 'ease-out' }
  );
}
function animateMachine(keyEl) {
  keyEl.animate([{ opacity: 0.9 }, { opacity: 0 }], {
    duration: Tone.Time('2n').toMilliseconds(),
    easing: 'ease-out'
  });
}

// Computer keyboard controls

builtInKeyboard.down(note => {
  humanKeyDown(note.note);
  hideUI();
});
builtInKeyboard.up(note => humanKeyUp(note.note));

// MIDI Controls

WebMidi.enable(err => {
  if (err) {
    console.error('WebMidi could not be enabled', err);
    return;
  }
  document.querySelector('.midi-not-supported').style.display = 'none';

  let withInputsMsg = document.querySelector('.midi-supported-with-inputs');
  let noInputsMsg = document.querySelector('.midi-supported-no-inputs');
  let inputSelector = document.querySelector('#midi-inputs');
  let outputSelector = document.querySelector('#outputs');
  let clockInputSelector = document.querySelector('#midi-clock-inputs');
  let clockOutputSelector = document.querySelector('#midi-clock-outputs');
  let activeInput,
    activeClockInputId,
    activeClockOutputId,
    transportTickerId,
    clockOutputTickerId,
    midiTickCount,
    lastBeatAt;

  function onInputsChange() {
    if (WebMidi.inputs.length === 0) {
      withInputsMsg.style.display = 'none';
      noInputsMsg.style.display = 'block';
      onActiveInputChange(null);
    } else {
      noInputsMsg.style.display = 'none';
      withInputsMsg.style.display = 'block';
      while (inputSelector.firstChild) {
        inputSelector.firstChild.remove();
      }
      for (let input of WebMidi.inputs) {
        let option = document.createElement('option');
        option.value = input.id;
        option.innerText = input.name;
        inputSelector.appendChild(option);
      }
      onActiveInputChange(WebMidi.inputs[0].id);
    }
  }

  function onOutputsChange() {
    while (outputSelector.firstChild) {
      outputSelector.firstChild.remove();
    }
    let internalOption = document.createElement('option');
    internalOption.value = 'internal';
    internalOption.innerText = 'Internal synth';
    outputSelector.appendChild(internalOption);
    for (let output of WebMidi.outputs) {
      let option = document.createElement('option');
      option.value = output.id;
      option.innerText = output.name;
      outputSelector.appendChild(option);
    }
    onActiveOutputChange('internal');
  }

  function onClockInputsChange() {
    if (WebMidi.inputs.length === 0) {
      onActiveClockInputChange('none');
    } else {
      while (clockInputSelector.firstChild) {
        clockInputSelector.firstChild.remove();
      }
      let option = document.createElement('option');
      option.value = 'none';
      option.innerText = 'None (internal clock)';
      clockInputSelector.appendChild(option);

      for (let input of WebMidi.inputs) {
        option = document.createElement('option');
        option.value = input.id;
        option.innerText = input.name;
        clockInputSelector.appendChild(option);
      }
      onActiveClockInputChange('none');
    }
  }

  function onClockOutputsChange() {
    while (clockOutputSelector.firstChild) {
      clockOutputSelector.firstChild.remove();
    }
    let noneOption = document.createElement('option');
    noneOption.value = 'none';
    noneOption.innerText = 'Not sending';
    clockOutputSelector.appendChild(noneOption);
    for (let output of WebMidi.outputs) {
      let option = document.createElement('option');
      option.value = output.id;
      option.innerText = output.name;
      clockOutputSelector.appendChild(option);
    }
    onActiveClockOutputChange('none');
  }

  function onActiveInputChange(id) {
    if (activeInput) {
      activeInput.removeListener();
    }
    let input = WebMidi.getInputById(id);
    if (input) {
      input.addListener('noteon', 1, e => {
        humanKeyDown(e.note.number, e.velocity);
        hideUI();
      });
      input.addListener('controlchange', 1, e => {
        if (e.controller.number === TEMPO_MIDI_CONTROLLER) {
          Tone.Transport.bpm.value = (e.value / 128) * MAX_MIDI_BPM;
          echo.delayTime.value = Tone.Time('8n.').toSeconds();
        }
      });
      input.addListener('noteoff', 1, e => humanKeyUp(e.note.number));
      for (let option of Array.from(inputSelector.children)) {
        option.selected = option.value === id;
      }
      activeInput = input;
    }
  }

  function onActiveOutputChange(id) {
    if (activeOutput !== 'internal') {
      outputs[activeOutput] = null;
    }
    activeOutput = id;
    if (activeOutput !== 'internal') {
      let output = WebMidi.getOutputById(id);
      outputs[id] = {
        play: (note, velocity = 1, time, hold = false) => {
          if (!hold) {
            let delay = (time - Tone.now()) * 1000;
            let duration = Tone.Time('16n').toMilliseconds();
            output.playNote(note, 'all', {
              time: delay > 0 ? `+${delay}` : WebMidi.now,
              velocity,
              duration
            });
          }
        },
        stop: (note, time) => {
          let delay = (time - Tone.now()) * 1000;
          output.stopNote(note, 2, {
            time: delay > 0 ? `+${delay}` : WebMidi.now
          });
        }
      };
    }
    for (let option of Array.from(outputSelector.children)) {
      option.selected = option.value === id;
    }
  }

  function startClockOutput() {
    let output = WebMidi.getOutputById(activeClockOutputId);
    clockOutputTickerId = Tone.Transport.scheduleRepeat(time => {
      let startDelay = time - Tone.context.currentTime;
      let quarter = Tone.Time('4n').toSeconds();
      for (let i = 0; i < 24; i++) {
        let tickDelay = startDelay + (quarter / 24) * i;
        output.sendClock({ time: `+${tickDelay * 1000}` });
      }
    }, '4n');
  }

  function stopClockOutput() {
    Tone.Transport.clear(clockOutputTickerId);
  }

  function onActiveClockOutputChange(id) {
    if (activeClockOutputId !== 'none') {
      stopClockOutput();
    }
    activeClockOutputId = id;
    if (activeClockOutputId !== 'none') {
      startClockOutput();
    }
    for (let option of Array.from(clockOutputSelector.children)) {
      option.selected = option.value === id;
    }
  }

  function incomingMidiClockStart() {
    midiTickCount = 0;
    tick = 0;
  }

  function incomingMidiClockStop() {
    midiTickCount = 0;
    applyHumanKeyChanges();
  }

  function incomingMidiClockTick(evt) {
    if (midiTickCount % 24 === 0) {
      if (lastBeatAt) {
        let beatDur = evt.timestamp - lastBeatAt;
        Tone.Transport.bpm.value = Math.round(60000 / beatDur);
        // Not sure why this doesn't sync through the BPM automatically. But it doesn't.
        echo.delayTime.value = Tone.Time('8n.').toSeconds();
      }
      lastBeatAt = evt.timestamp;
    }
    if (midiTickCount % 12 === 0) {
      doTick();
    }
    midiTickCount++;
  }

  function onActiveClockInputChange(id) {
    if (activeClockInputId === 'none') {
      Tone.Transport.clear(transportTickerId);
      transportTickerId = null;
    } else if (activeClockInputId) {
      let input = WebMidi.getInputById(activeClockInputId);
      input.removeListener('start', 'all', incomingMidiClockStart);
      input.removeListener('stop', 'all', incomingMidiClockStop);
      input.removeListener('clock', 'all', incomingMidiClockTick);
    }
    activeClockInputId = id;
    if (activeClockInputId === 'none') {
      transportTickerId = Tone.Transport.scheduleRepeat(doTick, '8n');
      Tone.Transport.bpm.value = DEFAULT_BPM;
      echo.delayTime.value = Tone.Time('8n.').toSeconds();
    } else {
      let input = WebMidi.getInputById(id);
      input.addListener('start', 'all', incomingMidiClockStart);
      input.addListener('stop', 'all', incomingMidiClockStop);
      input.addListener('clock', 'all', incomingMidiClockTick);
      midiTickCount = 0;
    }
    for (let option of Array.from(clockInputSelector.children)) {
      option.selected = option.value === id;
    }
  }

  onInputsChange();
  onOutputsChange();
  onClockInputsChange();
  onClockOutputsChange();

  WebMidi.addListener(
    'connected',
    () => (
      onInputsChange(),
      onOutputsChange(),
      onClockInputsChange(),
      onClockOutputsChange()
    )
  );
  WebMidi.addListener(
    'disconnected',
    () => (
      onInputsChange(),
      onOutputsChange(),
      onClockInputsChange(),
      onClockOutputsChange()
    )
  );
  inputSelector.addEventListener('change', evt =>
    onActiveInputChange(evt.target.value)
  );
  outputSelector.addEventListener('change', evt =>
    onActiveOutputChange(evt.target.value)
  );
  clockInputSelector.addEventListener('change', evt =>
    onActiveClockInputChange(evt.target.value)
  );
  clockOutputSelector.addEventListener('change', evt =>
    onActiveClockOutputChange(evt.target.value)
  );
});

// Mouse & touch Controls

let pointedNotes = new Set();

function updateTouchedNotes(evt) {
  let touchedNotes = new Set();
  for (let touch of Array.from(evt.touches)) {
    let element = document.elementFromPoint(touch.clientX, touch.clientY);
    let keyIndex = onScreenKeyboard.indexOf(element);
    if (keyIndex >= 0) {
      touchedNotes.add(MIN_NOTE + keyIndex);
      if (!evt.defaultPrevented) {
        evt.preventDefault();
      }
    }
  }
  for (let note of pointedNotes) {
    if (!touchedNotes.has(note)) {
      humanKeyUp(note);
      pointedNotes.delete(note);
    }
  }
  for (let note of touchedNotes) {
    if (!pointedNotes.has(note)) {
      humanKeyDown(note);
      pointedNotes.add(note);
    }
  }
}

onScreenKeyboard.forEach((noteEl, index) => {
  noteEl.addEventListener('mousedown', evt => {
    humanKeyDown(MIN_NOTE + index);
    pointedNotes.add(MIN_NOTE + index);
    evt.preventDefault();
  });
  noteEl.addEventListener('mouseover', () => {
    if (pointedNotes.size && !pointedNotes.has(MIN_NOTE + index)) {
      humanKeyDown(MIN_NOTE + index);
      pointedNotes.add(MIN_NOTE + index);
    }
  });
});
document.documentElement.addEventListener('mouseup', () => {
  pointedNotes.forEach(n => humanKeyUp(n));
  pointedNotes.clear();
});
document.documentElement.addEventListener('touchstart', updateTouchedNotes);
document.documentElement.addEventListener('touchmove', updateTouchedNotes);
document.documentElement.addEventListener('touchend', updateTouchedNotes);

// Temperature control

let tempSlider = new mdc.slider.MDCSlider(
  document.querySelector('#temperature')
);
tempSlider.listen('MDCSlider:change', () => (temperature = tempSlider.value));
document
  .querySelector('#pattern-length')
  .addEventListener('change', evt => (patternLength = evt.target.value));

// Pulse pattern switch

let pulsePatternControl = new mdc.switchControl.MDCSwitch(
  document.querySelector('.mdc-switch')
);
document
  .querySelector('#pulse-switch')
  .addEventListener('change', evt => (pulsePattern = evt.target.checked));

// Controls hiding

let container = document.querySelector('.container');

function hideUI() {
  container.classList.add('ui-hidden');
}
let scheduleHideUI = _.debounce(hideUI, 5000);
container.addEventListener('mousemove', () => {
  container.classList.remove('ui-hidden');
  scheduleHideUI();
});
container.addEventListener('touchstart', () => {
  container.classList.remove('ui-hidden');
  scheduleHideUI();
});

// Startup

function generateDummySequence() {
  // Generate a throwaway sequence to get the RNN loaded so it doesn't
  // cause jank later.
  return rnn.continueSequence(
    buildNoteSequence([{ note: 60, time: Tone.now() }]),
    20,
    temperature,
    ['Cm']
  );
}

let bufferLoadPromise = new Promise(res => Tone.Buffer.on('load', res));
Promise.all([bufferLoadPromise, rnn.initialize()])
  .then(generateDummySequence)
  .then(() => {
    Tone.Transport.start();
    Tone.Transport.bpm.value = DEFAULT_BPM;
    onScreenKeyboardContainer.classList.add('loaded');
    document.querySelector('.loading').remove();
  });

StartAudioContext(Tone.context, document.documentElement);

            
          
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