let midiData;

let currentNote = "C4"; // Starting note, adjust as needed

​

​

function preload() {

    loadMIDIFile('Fly_Me_to_the_Moon.mid');

}

​

function loadMIDIFile(filename) {

    httpDo(filename, {

        method: 'GET',

        responseType: 'arraybuffer'

    }, function(result) {

        midiData = result; // This will be an ArrayBuffer of the MIDI file

        onMIDILoaded();

    }, function(error) {

        console.error("Failed to load MIDI file:", error);

    });

}

​

function onMIDILoaded() {

    // Ensure MIDI data is loaded

    if (midiData) {

        // Parse MIDI data here using a MIDI parsing library

        parseMIDI(midiData);

​

        // Rest of the code that depends on midiData

    }

}

​

function parseMIDI(data) {

    // Implement MIDI parsing logic here

    // After parsing, you can build the Markov chain and generate melodies

}

​

function setup() {

    noCanvas();

    // Parse MIDI file and build Markov chain

    buildMarkovChain();

​

    // Set up Tone.js

    const synth = new Tone.Synth().toDestination();

    Tone.Transport.start();

    // Schedule melody generation and playback

    Tone.Transport.scheduleRepeat(time => {

        playMelody(synth);

    }, "1m"); // '1m' is one measure in Tone.js timing

}

​

function buildMarkovChain(midiData) {

    // Initialize an empty object for the Markov chain

    let chain = {};

​

    // Iterate over the MIDI data to fill the Markov chain

    for (let i = 0; i < midiData.length - 1; i++) {

        let currentNote = midiData[i];

        let nextNote = midiData[i + 1];

​

        if (!chain[currentNote]) {

            chain[currentNote] = {};

        }

​

        if (!chain[currentNote][nextNote]) {

            chain[currentNote][nextNote] = 0;

        }

​

        // Increment the count of this transition

        chain[currentNote][nextNote]++;

    }

​

    // Convert counts to probabilities

    for (let note in chain) {

        let total = 0;

        for (let next in chain[note]) {

            total += chain[note][next];

        }

        for (let next in chain[note]) {

            chain[note][next] /= total;

        }

    }

​

    return chain;

}

​

function generateMelody(markovChain, startNote, length) {

    let melody = [startNote];

    let currentNote = startNote;

​

    for (let i = 1; i < length; i++) {

        currentNote = chooseNextNote(markovChain, currentNote);

        melody.push(currentNote);

    }

​

    return melody;

}

​

function chooseNextNote(markovChain, currentNote) {

    let nextNotes = markovChain[currentNote];

    let total = 0;

    let r = Math.random();

​

    for (let note in nextNotes) {

        total += nextNotes[note];

        if (r <= total) {

            return note;

        }

    }

​

    // Fallback in case of rounding errors or empty chain

    return Object.keys(markovChain)[Math.floor(Math.random() * Object.keys(markovChain).length)];

}

​

function playMelody(synth) {

    let nextNote = generateNextNote();

    synth.triggerAttackRelease(nextNote, "8n"); // Play note for an eighth note duration

    currentNote = nextNote; // Update the current note

}