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我正在尝试创建几种不同的乐器，每种乐器都有 1 个或多个小节，所有小节都包含 1 个或多个节拍。

乐器有自己的节奏，单位为 BPM（每分钟节拍）。因此，如果乐器播放其“歌曲”，则以 ms 为单位的长度/持续时间由numberOfMeasuresInInstrument*beatsInSingleMeasure/instrumentTempo*60.0*1000.0 beatsInSingleMeasure 计算，也可以称为 a signature，因为音乐以 4/4 等单位定义。

我正在尝试循环播放“歌曲”。因此，如果我有多种持续时间不同的乐器，我希望它们同时开始，并演奏到自己的“成绩单”结束，然后等到所有乐器都完成（即最长的乐器持续时间）后再重新开始（这实际上是使每个“成绩单”的持续时间相等，并添加适当数量和速度的休止符以等于最长持续时间的乐器）。所以所有乐器都应该同时开始，并以它们的节奏间隔演奏它们的节拍，我认为这应该由另一个 setInterval() 管理。

这是一个小提琴来说明彼此之间的持续时间。假设第一个乐器演奏 2 秒，第二个演奏 1.6 秒，第三个演奏 1.5 秒。这将使第一个乐器的节拍每 0.66 秒播放一次，第二个乐器的节拍每 0.4 秒播放一次，第三个乐器的节拍每 0.25 秒播放一次。

我应该如何做到这一点？从概念上讲，嵌套间隔对我来说是有意义的，比如每 2 秒开始，并以适当的间隔播放你的节拍数（第一：每 0.66 秒三拍；第二：每 0.4 秒四拍；第三，每 0.25 秒六拍;)。这似乎比试图找出节拍持续时间的 LCD 并以这种方式播放它们更容易，因为我需要跟踪什么是节拍或休息，以及什么是填充物以确保它在 LCD 单元中，在在这种情况下，它是 .25、.4 和 .66 => .01666 秒的 LCD（也是 60Hz 或 1/60 秒）

目前我有以下内容：

//Which beat are we on?  first ones are in the negative to allow the 'song'to buffer once through the 'song', required by HTML5 Audio buffer
var beatCounter = 0-(signature*measuresCount-1);
// How many measures?
var measureCounter = 0;
// Are we waiting on another instrument to play, because we haven't reached the maximum play duration
var waitCounter = false;
function calculateWaiting(){
  if ( beatCounter*dur == currentInstrumentDuration && currentInstrumentDuration < maxDuration ){
    waitCounter = true;
  } else {
    waitCounter = false;
  }
};

//This is the instrument interval
this.animationIntervalID = setInterval((function(self) {
  return function() {
    //this is the beat interval                   
    this.beatAnimationIntervalID = setInterval((function(self) {
      return function() {
        //if we have not yet played all the beats and are waiting on the 
        if (waitCounter == false){            
          // As long as we are still have beats to play, keep playing                                                                
          if (beatCounter >= 0 && beatCounter < totalNumberOfBeats) {
            //Get all the beats
            var beats = $('#measure-rep-'+self.measureRepModel.cid).find('.audio-beat');
            // If the beat is selected, ie not a rest....
            var selected = self.parentMeasureModel.get('beats').models[beatCounter].get('selected');
            //animate it
            self.audioAnimate(beats.eq(beatCounter)[0], dur, selected);
          }
          //Increase the beatCounter until all of the beats have played, then reset the beatCounter
          if (beatCounter < (totalNumberOfBeats-1)) {
            beatCounter ++;
          } else {
            beatCounter = 0;
          }
          calculateWaiting();
        } else {
          // Waiting until the longest measure is complete
          console.log('waiting until the longer instrument is done playing');
        }
      };
    })(this), dur); //dur is the cycle at which every beat should be animating/lasting
  };
})(this), maxDuration); //maxDuration is the cycle at which every instrument should be waiting for to repeat

所以这里是较短的版本：

//This is the instrument interval
this.animationIntervalID = setInterval((function(self) {
  return function() {
    //this is the beat interval                   
    this.beatAnimationIntervalID = setInterval((function(self) {
      return function() { ... };
    })(this), dur); //dur is the cycle at which every beat should be animating/lasting
  };
})(this), maxDuration); //maxDuration is the cycle at which every instrument should be waiting for to repeat

以及我想要完成的线性视觉效果：

//Scroll this window to see it linearly with time
// Let's assume that the first instrument plays for a duration of 2 seconds, the second
// plays for 1.6 s, and the third plays for 1.5 s. That would make the first instruments 
// beats play at an interval of every .66s, the second instrument's beats play every
// .4 s, and the third instrument's beats play every .25s.
// 
// The LCD of all instrument's beats is .01666s (60 Hz or 1/60th of a second), so it
// should look something like this: P meaning Play the beat, p, meaning the beat still 
// being sustained, I meaning the LCD interval, and W meaning waiting 
//
//    0s                            .5s                           1s                            1.5s                          2s
//    ^                             ^                             ^                             ^                             ^
//    IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
// 1: PpppppppppppppppppppppppppppppppppppppppPpppppppppppppppppppppppppppppppppppppppPppppppppppppppppppppppppppppppppppppppp
// 2: PpppppppppppppppppppppppPpppppppppppppppppppppppPpppppppppppppppppppppppPpppppppppppppppppppppppWWWWWWWWWWWWWWWWWWWWWWWW
// 3: PppppppppppppppPppppppppppppppPppppppppppppppPppppppppppppppPppppppppppppppPppppppppppppppWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW
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