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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="progress pink">
    <div class="indeterminate white"></div>
  </div>
  <div class="app" style="display: none;">
    <div class="sequencer">
      <div class="steps"></div>
    </div>
    <a class="regenerate btn-floating btn-large waves-effect waves-light pink darken-2 pulse">
      <i class="material-icons">refresh</i>
    </a>
    <div class="controls">
      <div class="control">
        <a class="playpause btn-floating btn-large waves-effect waves-light blue">
          <i class="material-icons play-icon">play_arrow</i>
          <i class="material-icons pause-icon" style="display: none">pause</i>
        </a>
      </div>
      <div class="control">
        <div class="input-field grey-text">
          <select id="pattern-length">
            <option>4</option>
            <option>8</option>
            <option selected>16</option>
            <option>32</option>
          </select>
          Pattern length
        </div>
      </div>
      <div class="control">
        <p class="range-field grey-text">
          <input type="range" id="tempo" min="20" max="240" value="120" step="1"> Tempo
        </p>
      </div>
      <div class="control">
        <p class="range-field grey-text">
          <input type="range" id="swing" min="0.5" max="0.7" value="0.55" step="0.05"> Swing
        </p>
      </div>
      <div class="control">
        <p class="range-field grey-text">
          <input type="range" id="temperature" class="tooltipped" min="0.5" max="2" value="1.1" step="0.1" data-tooltip="Higher temperatures will make the neural network generates wilder patterns"
                 data-delay="500"> Temperature
        </p>
      </div>
    </div>
  </div>
  <div class="info">
    <p class="webmidi-enabled" style="display: none;">
      Output:
      <select class="midi-output"></select>
    </p>
    <p class="webmidi-enabled" style="display: none;">
      MIDI clock output:
      <select class="midi-clock-output"></select>
    </p>
    <p class="webmidi-enabled" style="display: none;">
      MIDI clock input:
      <select class="midi-clock-input"></select>
    </p>
    <p>This is an experimental drum machine powered by a deep neural network. To use it, define a seed pattern on the left,
      and use the &ldquo;generate&rdquo; button. A neural network will dream up a continuation to your seed pattern.</p>
    <p>Using the
      <a href="https://github.com/tensorflow/magenta/tree/master/magenta/models/drums_rnn">Drums 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>
    <p>A pen by
      <a href="https://twitter.com/teropa">@teropa</a>.</p>
  </div>
            
          
!
            
              html,
body,
.app {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;

  background-color: #111;
  color: white;
}

.progress {
  max-width: 30%;
  margin: 45vh auto 55vh auto;
}

.app {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;

  background: linear-gradient(to right, #010305, #131516);
}

.sequencer,
.controls {
  width: 80vw;
}
.controls {
  display: flex;
  flex-direction: row;
  justify-content: space-around;
}
.control {
  text-align: center;
}
.control input {
  margin-bottom: 20px;
}
.select-wrapper span.caret {
  color: inherit; /* Override materialize.css black */
}
.select-wrapper input.select-dropdown {
  margin-bottom: 10px;
}
.input-field {
  margin-top: 0;
}
input[type='range'] {
  border: 0;
}
input[type='range'] + .thumb {
  background-color: #2196f3;
}
input[type='range']::-webkit-slider-thumb {
  background-color: #2196f3;
}
input[type='range']::-moz-range-thumb {
  background-color: #2196f3;
}
input[type='range']::-ms-thumb {
  background-color: #2196f3;
}
.control .share {
  margin-top: 10px;
}
.midi-output,
.midi-clock-input,
.select-wrapper {
  max-width: 200px;
  margin: 0 auto;
}
.select-wrapper input {
  color: white;
}
.sequencer {
  position: relative;
  height: 70vh;
  margin: 20px 0;
  display: flex;
  flex-direction: row;
  perspective: 1000px;
  transform-style: preserve-3d;
}
.sequencer .legend {
  flex: 0.75;
  display: flex;
  flex-direction: column;
}
.drum-class {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  margin: 2.5px;

  font-size: 12px;
  color: #999;
}
.sequencer .steps {
  flex: 9;
  display: flex;
  flex-direction: row;
}
.step {
  flex: 1;
  display: flex;
  flex-direction: column;
  transform-style: preserve-3d;
}
.steps {
  transform-style: preserve-3d;
}
.gutter {
  width: 5px;
}
.gutter.seed-marker {
  background-color: #aaa;
  margin: 0 10px;
  cursor: move;
}
.gutter.seed-marker:hover {
  background-color: white;
}
.cell {
  margin: 2.5px 0;
  background-color: rgba(100, 100, 100, 0.1);
  border: 1px solid rgba(100, 100, 100, 0.2);
  border-radius: 3px;
  z-index: 0;
  transition: background-color 0.3s ease;
}

.cell:hover {
  background-color: rgba(100, 100, 100, 0.5);
}
.step:not(.regenerating) .cell.on {
  background-color: #64b5f6;
  opacity: 1;
}

.step.seed .cell.on {
  background-color: #e91e63;
}

.regenerate {
  position: absolute;
  visibility: hidden;
  font-size: 30px;
  line-height: 56px;
}

.kick {
  flex: 2;
  margin-bottom: 10px;
}
.snare {
  flex: 1;
  margin-top: 10px;
  margin-bottom: 10px;
}
.hi-hat-closed {
  flex: 1;
  margin-top: 10px;
}
.hi-hat-open {
  flex: 1;
  margin-bottom: 10px;
}
.tom-low {
  flex: 1;
  margin-top: 10px;
}
.tom-mid {
  flex: 1;
}
.tom-high {
  flex: 1;
  margin-bottom: 10px;
}
.clap {
  flex: 1;
  margin-top: 10px;
}
.rim {
  flex: 1;
}

.info {
  max-width: 50%;
  margin: 100px auto;
  text-align: center;
}
.info p {
  margin-top: 50px;
}

            
          
!
            
              const DRUM_CLASSES = [
  'Kick',
  'Snare',
  'Hi-hat closed',
  'Hi-hat open',
  'Tom low',
  'Tom mid',
  'Tom high',
  'Clap',
  'Rim'
];
const TIME_HUMANIZATION = 0.01;

let Tone = mm.Player.tone;

let sampleBaseUrl = 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/969699';

let reverb = new Tone.Convolver(
  `${sampleBaseUrl}/small-drum-room.wav`
).toMaster();
reverb.wet.value = 0.35;

let snarePanner = new Tone.Panner().connect(reverb);
new Tone.LFO(0.13, -0.25, 0.25).connect(snarePanner.pan).start();

let drumKit = [
  new Tone.Players({
    high: `${sampleBaseUrl}/808-kick-vh.mp3`,
    med: `${sampleBaseUrl}/808-kick-vm.mp3`,
    low: `${sampleBaseUrl}/808-kick-vl.mp3`
  }).toMaster(),
  new Tone.Players({
    high: `${sampleBaseUrl}/flares-snare-vh.mp3`,
    med: `${sampleBaseUrl}/flares-snare-vm.mp3`,
    low: `${sampleBaseUrl}/flares-snare-vl.mp3`
  }).connect(snarePanner),
  new Tone.Players({
    high: `${sampleBaseUrl}/808-hihat-vh.mp3`,
    med: `${sampleBaseUrl}/808-hihat-vm.mp3`,
    low: `${sampleBaseUrl}/808-hihat-vl.mp3`
  }).connect(new Tone.Panner(-0.5).connect(reverb)),
  new Tone.Players({
    high: `${sampleBaseUrl}/808-hihat-open-vh.mp3`,
    med: `${sampleBaseUrl}/808-hihat-open-vm.mp3`,
    low: `${sampleBaseUrl}/808-hihat-open-vl.mp3`
  }).connect(new Tone.Panner(-0.5).connect(reverb)),
  new Tone.Players({
    high: `${sampleBaseUrl}/slamdam-tom-low-vh.mp3`,
    med: `${sampleBaseUrl}/slamdam-tom-low-vm.mp3`,
    low: `${sampleBaseUrl}/slamdam-tom-low-vl.mp3`
  }).connect(new Tone.Panner(-0.4).connect(reverb)),
  new Tone.Players({
    high: `${sampleBaseUrl}/slamdam-tom-mid-vh.mp3`,
    med: `${sampleBaseUrl}/slamdam-tom-mid-vm.mp3`,
    low: `${sampleBaseUrl}/slamdam-tom-mid-vl.mp3`
  }).connect(reverb),
  new Tone.Players({
    high: `${sampleBaseUrl}/slamdam-tom-high-vh.mp3`,
    med: `${sampleBaseUrl}/slamdam-tom-high-vm.mp3`,
    low: `${sampleBaseUrl}/slamdam-tom-high-vl.mp3`
  }).connect(new Tone.Panner(0.4).connect(reverb)),
  new Tone.Players({
    high: `${sampleBaseUrl}/909-clap-vh.mp3`,
    med: `${sampleBaseUrl}/909-clap-vm.mp3`,
    low: `${sampleBaseUrl}/909-clap-vl.mp3`
  }).connect(new Tone.Panner(0.5).connect(reverb)),
  new Tone.Players({
    high: `${sampleBaseUrl}/909-rim-vh.wav`,
    med: `${sampleBaseUrl}/909-rim-vm.wav`,
    low: `${sampleBaseUrl}/909-rim-vl.wav`
  }).connect(new Tone.Panner(0.5).connect(reverb))
];
let midiDrums = [36, 38, 42, 46, 41, 43, 45, 49, 51];
let reverseMidiMapping = new Map([
  [36, 0],
  [35, 0],
  [38, 1],
  [27, 1],
  [28, 1],
  [31, 1],
  [32, 1],
  [33, 1],
  [34, 1],
  [37, 1],
  [39, 1],
  [40, 1],
  [56, 1],
  [65, 1],
  [66, 1],
  [75, 1],
  [85, 1],
  [42, 2],
  [44, 2],
  [54, 2],
  [68, 2],
  [69, 2],
  [70, 2],
  [71, 2],
  [73, 2],
  [78, 2],
  [80, 2],
  [46, 3],
  [67, 3],
  [72, 3],
  [74, 3],
  [79, 3],
  [81, 3],
  [45, 4],
  [29, 4],
  [41, 4],
  [61, 4],
  [64, 4],
  [84, 4],
  [48, 5],
  [47, 5],
  [60, 5],
  [63, 5],
  [77, 5],
  [86, 5],
  [87, 5],
  [50, 6],
  [30, 6],
  [43, 6],
  [62, 6],
  [76, 6],
  [83, 6],
  [49, 7],
  [55, 7],
  [57, 7],
  [58, 7],
  [51, 8],
  [52, 8],
  [53, 8],
  [59, 8],
  [82, 8]
]);

let temperature = 1.0;

let outputs = {
  internal: {
    play: (drumIdx, velocity, time) => {
      drumKit[drumIdx].get(velocity).start(time);
    }
  }
};

let rnn = new mm.MusicRNN(
  'https://storage.googleapis.com/download.magenta.tensorflow.org/tfjs_checkpoints/music_rnn/drum_kit_rnn'
);
Promise.all([
  rnn.initialize(),
  new Promise(res => Tone.Buffer.on('load', res))
]).then(([vars]) => {
  let state = {
    patternLength: 32,
    seedLength: 4,
    swing: 0.55,
    pattern: [[0], [], [2]].concat(_.times(32, i => [])),
    tempo: 120
  };
  let stepEls = [],
    hasBeenStarted = false,
    oneEighth = Tone.Time('8n').toSeconds(),
    activeOutput = 'internal',
    midiClockSender = null,
    midiClockStartSent = false,
    activeClockInput = 'none',
    currentSchedulerId,
    stepCounter;

  function generatePattern(seed, length) {
    let seedSeq = toNoteSequence(seed);
    return rnn
      .continueSequence(seedSeq, length, temperature)
      .then(r => seed.concat(fromNoteSequence(r, length)));
  }

  function getStepVelocity(step) {
    if (step % 4 === 0) {
      return 'high';
    } else if (step % 2 === 0) {
      return 'med';
    } else {
      return 'low';
    }
  }

  function humanizeTime(time) {
    return time - TIME_HUMANIZATION / 2 + Math.random() * TIME_HUMANIZATION;
  }

  function tick(time = Tone.now() - Tone.context.lookAhead) {
    if (_.isNumber(stepCounter) && state.pattern) {
      stepCounter++;
      if (midiClockSender) midiClockSender(time, stepCounter);

      let stepIdx = stepCounter % state.pattern.length;
      let isSwung = stepIdx % 2 !== 0;
      if (isSwung) {
        time += (state.swing - 0.5) * oneEighth;
      }
      let velocity = getStepVelocity(stepIdx);
      let drums = state.pattern[stepIdx];
      drums.forEach(d => {
        let humanizedTime = stepIdx === 0 ? time : humanizeTime(time);
        outputs[activeOutput].play(d, velocity, humanizedTime);
        visualizePlay(humanizedTime, stepIdx, d);
      });
    }
  }

  function startPattern() {
    stepCounter = -1;
    midiClockStartSent = false;
    updatePlayPauseIcons();
  }

  function stopPattern() {
    stepCounter = null;
    updatePlayPauseIcons();
  }

  function visualizePlay(time, stepIdx, drumIdx) {
    Tone.Draw.schedule(() => {
      if (!stepEls[stepIdx]) return;
      let animTime = oneEighth * 4 * 1000;
      let cellEl = stepEls[stepIdx].cellEls[drumIdx];
      if (cellEl.classList.contains('on')) {
        let baseColor = stepIdx < state.seedLength ? '#e91e63' : '#64b5f6';
        cellEl.animate(
          [
            {
              transform: 'translateZ(-100px)',
              backgroundColor: '#fad1df'
            },
            {
              transform: 'translateZ(50px)',
              offset: 0.7
            },
            { transform: 'translateZ(0)', backgroundColor: baseColor }
          ],
          { duration: animTime, easing: 'cubic-bezier(0.23, 1, 0.32, 1)' }
        );
      }
    }, time);
  }

  function renderPattern(regenerating = false) {
    let seqEl = document.querySelector('.sequencer .steps');
    while (stepEls.length > state.pattern.length) {
      let { stepEl, gutterEl } = stepEls.pop();
      stepEl.remove();
      if (gutterEl) gutterEl.remove();
    }
    for (let stepIdx = 0; stepIdx < state.pattern.length; stepIdx++) {
      let step = state.pattern[stepIdx];
      let stepEl, gutterEl, cellEls;
      if (stepEls[stepIdx]) {
        stepEl = stepEls[stepIdx].stepEl;
        gutterEl = stepEls[stepIdx].gutterEl;
        cellEls = stepEls[stepIdx].cellEls;
      } else {
        stepEl = document.createElement('div');
        stepEl.classList.add('step');
        stepEl.dataset.stepIdx = stepIdx;
        seqEl.appendChild(stepEl);
        cellEls = [];
      }

      stepEl.style.flex = stepIdx % 2 === 0 ? state.swing : 1 - state.swing;

      if (!gutterEl && stepIdx < state.pattern.length - 1) {
        gutterEl = document.createElement('div');
        gutterEl.classList.add('gutter');
        seqEl.insertBefore(gutterEl, stepEl.nextSibling);
      } else if (gutterEl && stepIdx >= state.pattern.length) {
        gutterEl.remove();
        gutterEl = null;
      }

      if (gutterEl && stepIdx === state.seedLength - 1) {
        gutterEl.classList.add('seed-marker');
      } else if (gutterEl) {
        gutterEl.classList.remove('seed-marker');
      }

      for (let cellIdx = 0; cellIdx < DRUM_CLASSES.length; cellIdx++) {
        let cellEl;
        if (cellEls[cellIdx]) {
          cellEl = cellEls[cellIdx];
        } else {
          cellEl = document.createElement('div');
          cellEl.classList.add('cell');
          cellEl.classList.add(_.kebabCase(DRUM_CLASSES[cellIdx]));
          cellEl.dataset.stepIdx = stepIdx;
          cellEl.dataset.cellIdx = cellIdx;
          stepEl.appendChild(cellEl);
          cellEls[cellIdx] = cellEl;
        }
        if (step.indexOf(cellIdx) >= 0) {
          cellEl.classList.add('on');
        } else {
          cellEl.classList.remove('on');
        }
      }
      stepEls[stepIdx] = { stepEl, gutterEl, cellEls };

      let stagger = stepIdx * (300 / (state.patternLength - state.seedLength));
      setTimeout(() => {
        if (stepIdx < state.seedLength) {
          stepEl.classList.add('seed');
        } else {
          stepEl.classList.remove('seed');
          if (regenerating) {
            stepEl.classList.add('regenerating');
          } else {
            stepEl.classList.remove('regenerating');
          }
        }
      }, stagger);
    }

    setTimeout(repositionRegenerateButton, 0);
  }

  function repositionRegenerateButton() {
    let regenButton = document.querySelector('.regenerate');
    let sequencerEl = document.querySelector('.sequencer');
    let seedMarkerEl = document.querySelector('.gutter.seed-marker');
    let regenLeft =
      sequencerEl.offsetLeft +
      seedMarkerEl.offsetLeft +
      seedMarkerEl.offsetWidth / 2 -
      regenButton.offsetWidth / 2;
    let regenTop =
      sequencerEl.offsetTop +
      seedMarkerEl.offsetTop +
      seedMarkerEl.offsetHeight / 2 -
      regenButton.offsetHeight / 2;
    regenButton.style.left = `${regenLeft}px`;
    regenButton.style.top = `${regenTop}px`;
    regenButton.style.visibility = 'visible';
  }

  function regenerate() {
    let seed = _.take(state.pattern, state.seedLength);
    renderPattern(true);
    return generatePattern(seed, state.patternLength - seed.length).then(
      result => {
        state.pattern = result;
        onPatternUpdated();
      }
    );
  }

  function onPatternUpdated() {
    stopPattern();
    renderPattern();
  }

  function toggleStep(cellEl) {
    if (state.pattern && cellEl.classList.contains('cell')) {
      let stepIdx = +cellEl.dataset.stepIdx;
      let cellIdx = +cellEl.dataset.cellIdx;
      let isOn = cellEl.classList.contains('on');
      if (isOn) {
        _.pull(state.pattern[stepIdx], cellIdx);
        cellEl.classList.remove('on');
      } else {
        state.pattern[stepIdx].push(cellIdx);
        cellEl.classList.add('on');
      }
    }
  }

  function toNoteSequence(pattern) {
    return mm.sequences.quantizeNoteSequence(
      {
        ticksPerQuarter: 220,
        totalTime: pattern.length / 2,
        timeSignatures: [
          {
            time: 0,
            numerator: 4,
            denominator: 4
          }
        ],
        tempos: [
          {
            time: 0,
            qpm: 120
          }
        ],
        notes: _.flatMap(pattern, (step, index) =>
          step.map(d => ({
            pitch: midiDrums[d],
            startTime: index * 0.5,
            endTime: (index + 1) * 0.5
          }))
        )
      },
      1
    );
  }

  function fromNoteSequence(seq, patternLength) {
    let res = _.times(patternLength, () => []);
    for (let { pitch, quantizedStartStep } of seq.notes) {
      res[quantizedStartStep].push(reverseMidiMapping.get(pitch));
    }
    return res;
  }

  function setSwing(newSwing) {
    state.swing = newSwing;
    renderPattern();
  }

  function updatePlayPauseIcons() {
    if (_.isNumber(stepCounter)) {
      document.querySelector('.playpause .pause-icon').style.display = null;
      document.querySelector('.playpause .play-icon').style.display = 'none';
    } else {
      document.querySelector('.playpause .play-icon').style.display = null;
      document.querySelector('.playpause .pause-icon').style.display = 'none';
    }
  }

  WebMidi.enable(err => {
    if (err) {
      console.error('WebMidi could not be enabled', err);
      return;
    }
    document
      .querySelectorAll('.webmidi-enabled')
      .forEach(e => (e.style.display = 'block'));
    let outputSelector = document.querySelector('.midi-output');
    let clockOutputSelector = document.querySelector('.midi-clock-output');
    let clockInputSelector = document.querySelector('.midi-clock-input');
    let activeClockOutput,
      midiClockCounter = 0,
      eighthsCounter = 0,
      lastEighthAt;

    function onDevicesChanged() {
      while (outputSelector.firstChild) {
        outputSelector.firstChild.remove();
      }
      let internalOption = document.createElement('option');
      internalOption.value = 'internal';
      internalOption.innerText = 'Internal drumkit';
      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);
      }
      $(outputSelector).formSelect();
      onActiveOutputChange('internal');

      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);
      }
      $(clockOutputSelector).formSelect();
      onActiveClockOutputChange('none');

      while (clockInputSelector.firstChild) {
        clockInputSelector.firstChild.remove();
      }
      noneOption = document.createElement('option');
      noneOption.value = 'none';
      noneOption.innerText = 'None (using internal clock)';
      clockInputSelector.appendChild(noneOption);
      for (let input of WebMidi.inputs) {
        let option = document.createElement('option');
        option.value = input.id;
        option.innerText = input.name;
        clockInputSelector.appendChild(option);
      }
      $(clockInputSelector).formSelect();
      onActiveClockInputChange('none');
    }

    function onActiveOutputChange(id) {
      if (activeOutput !== 'internal') {
        outputs[activeOutput] = null;
      }
      activeOutput = id;
      if (activeOutput !== 'internal') {
        let output = WebMidi.getOutputById(id);
        outputs[id] = {
          play: (drumIdx, velo, time) => {
            let delay = (time - Tone.now()) * 1000;
            let duration = (oneEighth / 2) * 1000;
            let velocity = { high: 1, med: 0.75, low: 0.5 };
            output.playNote(midiDrums[drumIdx], 1, {
              time: delay > 0 ? `+${delay}` : WebMidi.now,
              velocity,
              duration
            });
          }
        };
      }
      for (let option of Array.from(outputSelector.children)) {
        option.selected = option.value === id;
      }
    }

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

    function startSendingMidiClock() {
      let output = WebMidi.getOutputById(activeClockOutput);
      midiClockSender = function(time, stepCounter) {
        let startDelay = time - Tone.now() + Tone.context.lookAhead;
        let sixteenth = Tone.Time('16n').toSeconds();
        for (let i = 0; i < 6; i++) {
          let tickDelay = startDelay + (sixteenth / 6) * i;
          if (i === 0 && stepCounter === 0 && !midiClockStartSent) {
            console.log('sending clock start');
            output.sendStart({ time: `+${tickDelay * 1000}` });
            midiClockStartSent = true;
          }
          output.sendClock({ time: `+${tickDelay * 1000}` });
        }
      };
    }

    function stopSendingMidiClock() {
      midiClockSender = null;
      midiClockStartSent = false;
    }

    function incomingMidiClockStart() {
      midiClockCounter = 0;
      eighthsCounter = 0;
      startPattern();
    }

    function incomingMidiClockStop() {
      midiClockCounter = 0;
      eighthsCounter = 0;
      lastEighthAt = null;
      stopPattern();
    }

    function incomingMidiClockTick(evt) {
      if (midiClockCounter % 6 === 0) {
        tick();
      }
      if (eighthsCounter % 12 === 0) {
        if (lastEighthAt) {
          oneEighth = (evt.timestamp - lastEighthAt) / 1000;
        }
        lastEighthAt = evt.timestamp;
      }
      midiClockCounter++;
      eighthsCounter++;
    }

    function onActiveClockInputChange(id) {
      if (activeClockInput === 'none') {
        Tone.Transport.clear(currentSchedulerId);
        currentSchedulerId = null;
      } else if (activeClockInput) {
        let input = WebMidi.getInputById(activeClockInput);
        input.removeListener('start', 'all', incomingMidiClockStart);
        input.removeListener('stop', 'all', incomingMidiClockStop);
        input.removeListener('clock', 'all', incomingMidiClockTick);
      }
      activeClockInput = id;
      if (activeClockInput === 'none') {
        currentSchedulerId = Tone.Transport.scheduleRepeat(tick, '16n');
        oneEighth = 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);
      }
    }

    onDevicesChanged();
    WebMidi.addListener('connected', onDevicesChanged);
    WebMidi.addListener('disconnected', onDevicesChanged);

    $(outputSelector)
      .on('change', evt => onActiveOutputChange(evt.target.value))
      .formSelect();
    $(clockOutputSelector)
      .on('change', evt => onActiveClockOutputChange(evt.target.value))
      .formSelect();
    $(clockInputSelector)
      .on('change', evt => onActiveClockInputChange(evt.target.value))
      .formSelect();
  });

  document.querySelector('.app').addEventListener('click', event => {
    if (event.target.classList.contains('cell')) {
      toggleStep(event.target);
    }
  });
  document.querySelector('.regenerate').addEventListener('click', event => {
    event.preventDefault();
    event.currentTarget.classList.remove('pulse');
    document.querySelector('.playpause').classList.remove('pulse');
    regenerate().then(() => {
      if (!hasBeenStarted) {
        Tone.context.resume();
        Tone.Transport.start();
        hasBeenStarted = true;
      }
      if (Tone.Transport.state === 'started') {
        setTimeout(startPattern, 0);
      }
    });
  });
  document.querySelector('.playpause').addEventListener('click', event => {
    event.preventDefault();
    document.querySelector('.playpause').classList.remove('pulse');
    if (_.isNumber(stepCounter)) {
      stopPattern();
      Tone.Transport.pause();
    } else {
      Tone.context.resume();
      Tone.Transport.start();
      startPattern();
      hasBeenStarted = true;
    }
  });

  let draggingSeedMarker = false;
  document.querySelector('.app').addEventListener('mousedown', evt => {
    let el = evt.target;
    if (
      el.classList.contains('gutter') &&
      el.classList.contains('seed-marker')
    ) {
      draggingSeedMarker = true;
      evt.preventDefault();
    }
  });
  document.querySelector('.app').addEventListener('mouseup', () => {
    draggingSeedMarker = false;
  });
  document.querySelector('.app').addEventListener('mouseover', evt => {
    if (draggingSeedMarker) {
      let el = evt.target;
      while (el) {
        if (el.classList.contains('step')) {
          let stepIdx = +el.dataset.stepIdx;
          if (stepIdx > 0) {
            state.seedLength = stepIdx;
            renderPattern();
          }
          break;
        }
        el = el.parentElement;
      }
    }
  });
  document
    .querySelector('#swing')
    .addEventListener('input', evt => setSwing(+evt.target.value));
  document
    .querySelector('#temperature')
    .addEventListener('input', evt => (temperature = +evt.target.value));
  document.querySelector('#tempo').addEventListener('input', evt => {
    Tone.Transport.bpm.value = state.tempo = +evt.target.value;
    oneEighth = Tone.Time('8n').toSeconds();
  });

  $('#pattern-length')
    .on('change', evt => setPatternLength(+evt.target.value))
    .formSelect();

  window.addEventListener('resize', repositionRegenerateButton);

  renderPattern();

  document.querySelector('.progress').remove();
  document.querySelector('.app').style.display = null;
});

            
          
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