​

let major = ["C","Dm","Em","F","G","Adim","Bm"];

let minor = ["Am","Bdim","C","Dm","Em","F","G",];

​

let tonProjMaj = {

  1 : [2,3,4,5,7],

  2 : [7,5],

  3 : [4,2],

  4 : [2,7,5],

  5 : [1],

  7 : [5,1]  

}

​

let tonProjMin = {

  1 : [3,4,5,6,7],

  3 : [6,4],

  4 : [7,5],

  5 : [1],

  6 : [4],

  7 : [5,1,3]  

}

​

function setup() {

  let p = createP();

  genMajButton = createButton("new major progression")

  genMinButton = createButton("new minor progression")

  genMajButton.mousePressed(newMajor);

  genMinButton.mousePressed(newMinor);

  txt = createP("");

  p.child(createCanvas(0,0));

  p.child(genMajButton)

  p.child(createSpan(" "))

  p.child(genMinButton)

  p.child(txt)

}

​

function draw() {

}

​

function newMajor(){

  let notes = [1];

  while(true){

    let possibleNotes = tonProjMaj[notes.slice(-1)]

    let nextNote = possibleNotes[floor(random(possibleNotes.length))]

    if (nextNote==1){

      break

    }

    notes.push(nextNote);

  }

  let progression = major[notes[0]-1]

  for (let i=1;i<notes.length;i++){

    progression += " "

    progression += major[notes[i]-1]

  }

  txt.html(progression)

}

​

function newMinor(){

  let notes = [1];

  while(true){

    let possibleNotes = tonProjMin[notes.slice(-1)]

    let nextNote = possibleNotes[floor(random(possibleNotes.length))]

    if (nextNote==1){

      break

    }

    notes.push(nextNote);

  }

  let progression = minor[notes[0]-1]

  for (let i=1;i<notes.length;i++){

    progression += " "

    progression += minor[notes[i]-1]

  }

  txt.html(progression)

}