// 17.0 keyPressed notes 1QAZ

​

let a_keys = {};

let a_waves = {};

let fade_in = 0.1;

let fade_out = 0.5;

let a_volume = 0.1;

​

function setup() {

  createCanvas(512, 512);

}

​

function draw() {

  background(200);

​

  fill(0, 0, 0);

  textSize(28)

​

  let h = height / 2;

  text('Press any key on row 1, Q, A, Z', 10, h);

  text(JSON.stringify(a_keys), 10, h + 30);

​

  text('key=' + key + ' keyCode=' + keyCode, 10, h + 60);  

}

​

// Create a new oscillator on each keypress

function keyPressed() {

  // print('keyPressed', key);

​

  let freq = a_notes[key];

  // print('freq', freq)

  if (freq !== undefined) {

    a_keys[key] = freq || -1;

    let wave = a_waves[key];

    if (!wave) {

      wave = new p5.Oscillator();

      wave.setType('sine');

      wave.freq(freq);

      wave.start();

      wave.amp(0);

      wave.amp(a_volume, fade_in);

      a_waves[key] = wave;

    }

  }

​

  // prevent any default behavior

  return false;

}

​

function keyReleased() {

  // print('keyReleased', key);

  delete a_keys[key];

​

  let wave = a_waves[key];

  if (wave) {

    wave.amp(0, fade_out);

    delete a_waves[key];

  }

​

  // prevent any default behavior

  return false;

}

​

// https://en.wikipedia.org/wiki/Piano_key_frequencies

​

// https://editor.p5js.org/icm4.0/sketches/NArBLGfRM

// Random Diatonic Chords 2:4 Chords

​

// A-G-K --> "C Major cord"

// D-J-; --> "D cord"

// G-L-Enter --> "E Major cord"

//