jonathanlurie · September 17, 2017 20:31
diff --git a/index.html b/index.html
 <html>
 <head>
 </head>
 <body>
 <script>

 // index of the sound currently being played (-1 if none)
 var playingIndex = -1;
 // duration in second of the fading
 var fadeDuration = 2;
 // duration in ms of the refreshing of the fading
 var intervalRefreshMs = 100;

 var soundPaths = [
  'home-at-last.mp3',
  'kendrick.mp3'
 ];

 var soundList = new Array( soundPaths.length );

 for(var i=0; i<soundList.length; i++){
  var aSound = new Audio(soundPaths[i]);
  aSound.loop = true;


  // works
  aSound.onprogress = function(p){

    console.log(p);
  }

  soundList[i] = aSound;
 }

 soundList[0].oncanplay = function( info ){
  console.log(">>>>>>>>>> CAN PLAY ");
  console.log( info );
  playFadeIn(0);
 }


 /*
 var current = new Audio('home-at-last.mp3');
 current.play();
 console.log( current );

 var fadeAudio = setInterval(function () {

  // Only fade if past the fade out point or not at zero already
  if ((sound.currentTime >= fadePoint) && (sound.volume != 0.0)) {
      sound.volume -= 0.1;
  }
  // When volume at zero stop all the intervalling
  if (sound.volume === 0.0) {
      clearInterval(fadeAudio);
  }
 }, 200);


 function play( index ){

 }
 */


 function playFadeIn( index ){


  if( index < 0 || index >= soundList.length ){
    console.warn("The index of the sound to play is out of bound.");
    return;
  }

  var sound = soundList[index];

  // abort is the very same song is already playing
  if( index === playingIndex && !sound.paused ){
    console.log("Sound already playing.");
    return;
  }

  sound.volume = 0.0;
  sound.play();
  playingIndex = index;

  var fadeInInterval = setInterval(function () {
    var newVolume = sound.volume + intervalRefreshMs / (1000 * fadeDuration);

    if( newVolume >= 1 ){
      sound.volume = 1.0;
      clearInterval(fadeInInterval);
    }else{
      sound.volume = newVolume;
    }

  }, intervalRefreshMs);

 }


 function pauseFadeOut( forceStop = false ){
  if( playingIndex === -1 )
    return;

  var sound = soundList[playingIndex];

  var fadeOutInterval = setInterval(function () {
    var newVolume = sound.volume - intervalRefreshMs / (1000 * fadeDuration);

    if( newVolume <= 0 ){
      sound.volume = 0;
      if( forceStop )
        sound.stop();
      else
        sound.pause()
      clearInterval(fadeOutInterval);
    }else{
      sound.volume = newVolume;
    }

  }, intervalRefreshMs);

 }


 function goToNextSound( nextSoundIndex = -1 ){
  if( playingIndex == nextSoundIndex){
    console.log("same sound playing");
    return;
  }

  // fadeout the current one
  if( playingIndex !== -1 ){
    pauseFadeOut();
  }

  if( nextSoundIndex == -1 ){
    //defining the new playing index
    nextSoundIndex = playingIndex == (soundList.length - 1) ? 0 : playingIndex + 1;
    console.log( "auto next ");
  }

  playFadeIn( nextSoundIndex );

 }

 function pause(){
  pauseFadeOut()
 }

 function resume(){
  playFadeIn( playingIndex );
 }

 //playFadeIn(0);


 </script>
 </body>
 </html>
	<html>
	<head>
	</head>
	<body>
	<script>

	// index of the sound currently being played (-1 if none)
	var playingIndex = -1;
	// duration in second of the fading
	var fadeDuration = 2;
	// duration in ms of the refreshing of the fading
	var intervalRefreshMs = 100;

	var soundPaths = [
	'home-at-last.mp3',
	'kendrick.mp3'
	];

	var soundList = new Array( soundPaths.length );

	for(var i=0; i<soundList.length; i++){
	var aSound = new Audio(soundPaths[i]);
	aSound.loop = true;


	// works
	aSound.onprogress = function(p){

	console.log(p);
	}

	soundList[i] = aSound;
	}

	soundList[0].oncanplay = function( info ){
	console.log(">>>>>>>>>> CAN PLAY ");
	console.log( info );
	playFadeIn(0);
	}


	/*
	var current = new Audio('home-at-last.mp3');
	current.play();
	console.log( current );

	var fadeAudio = setInterval(function () {

	// Only fade if past the fade out point or not at zero already
	if ((sound.currentTime >= fadePoint) && (sound.volume != 0.0)) {
	sound.volume -= 0.1;
	}
	// When volume at zero stop all the intervalling
	if (sound.volume === 0.0) {
	clearInterval(fadeAudio);
	}
	}, 200);


	function play( index ){

	}
	*/


	function playFadeIn( index ){


	if( index < 0 \|\| index >= soundList.length ){
	console.warn("The index of the sound to play is out of bound.");
	return;
	}

	var sound = soundList[index];

	// abort is the very same song is already playing
	if( index === playingIndex && !sound.paused ){
	console.log("Sound already playing.");
	return;
	}

	sound.volume = 0.0;
	sound.play();
	playingIndex = index;

	var fadeInInterval = setInterval(function () {
	var newVolume = sound.volume + intervalRefreshMs / (1000 * fadeDuration);

	if( newVolume >= 1 ){
	sound.volume = 1.0;
	clearInterval(fadeInInterval);
	}else{
	sound.volume = newVolume;
	}

	}, intervalRefreshMs);

	}


	function pauseFadeOut( forceStop = false ){
	if( playingIndex === -1 )
	return;

	var sound = soundList[playingIndex];

	var fadeOutInterval = setInterval(function () {
	var newVolume = sound.volume - intervalRefreshMs / (1000 * fadeDuration);

	if( newVolume <= 0 ){
	sound.volume = 0;
	if( forceStop )
	sound.stop();
	else
	sound.pause()
	clearInterval(fadeOutInterval);
	}else{
	sound.volume = newVolume;
	}

	}, intervalRefreshMs);

	}


	function goToNextSound( nextSoundIndex = -1 ){
	if( playingIndex == nextSoundIndex){
	console.log("same sound playing");
	return;
	}

	// fadeout the current one
	if( playingIndex !== -1 ){
	pauseFadeOut();
	}

	if( nextSoundIndex == -1 ){
	//defining the new playing index
	nextSoundIndex = playingIndex == (soundList.length - 1) ? 0 : playingIndex + 1;
	console.log( "auto next ");
	}

	playFadeIn( nextSoundIndex );

	}

	function pause(){
	pauseFadeOut()
	}

	function resume(){
	playFadeIn( playingIndex );
	}

	//playFadeIn(0);


	</script>
	</body>
	</html>