Phenakistiscope

let file;

let tune;

let angle = 0;

let av = 1;

let saveav = 1;

let mode = 'opening';

​

function preload() {

  file = loadImage('muybridge.jpg')

  soundFormats('mp3', 'ogg');

  tune = loadSound('dailydownload_20151231_128.mp3');

}

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  background(100);

  angleMode(DEGREES);

  imageMode(CENTER);

  file.resize(2 * height, 2 * height);

}

​

function draw() {

  switch (mode) {

    case 'opening':

      background(255);

      fill(0);

      textAlign(CENTER, CENTER);

      textSize(height / 14);

      text('click to start audio', width / 2, height / 2);

      break;

    case 'playing':

      background(255);

      translate(width / 2, 0);

      push();

      rotate(angle);

      image(file, 0, 0);

      pop();

      angle += av;

      checkInputs();

      break;

  }

}

​

function checkInputs() {

  if (keyIsDown(RIGHT_ARROW)) {

    av -= 0.1;

    saveav -= 0.1;

  }

  if (keyIsDown(LEFT_ARROW)) {

    av += 0.1;

    saveav += 0.1;

  }

  if (mouseIsPressed) {

    av = lerp(av, 0, 0.05);

  } else {

    av = lerp(av, saveav, 0.05);

  }

  saveav = map(mouseX, 0,width, 9*PI,-9*PI);

}

​

function mousePressed() {

  if (!tune.isPlaying()) {

    tune.play();

    mode = 'playing';

  } else {

    saveav = av;

  }

}