Enhancing The User Experience: GUI and Sound - Learn Unity3D Programming with UnityScript - page 326

function Update() {
if (!audio.isPlaying) {
introMusicIsPlaying = false;
}
if (!introMusicIsPlaying && !looping) {
looping = true;
LoopBackgroundMusic();
}
}

function PlayBackgroundMusic () {
if(audio.isPlaying == true) {
audio.Stop();
}
audio.Play();
}

function LoopBackgroundMusic () {
if(audio.isPlaying == true) {
audio.Stop();
}
audio.clip = musicLoop;
audio.loop = enabled;
audio.Play();
}

Breaking this down:

(1) public var musicLoop : AudioClip;

1. Declare a reference variable of type AudioClip to hold the second audio clip

to be played, and name it musicLoop .

(2) private var introMusicIsPlaying : boolean = true;

2. Declare a private boolean variable named introMusicIsPlaying and set it to

true , since PlayBackgroundMusic() is called from the Start() function and
will immediately begin playing the intro clip.

(3) private var looping : boolean = false;

3. Declare a private boolean variable named looping and set it to false .

(4) if (!audio.isPlaying)

4. In the Update() function, check to see when the intro clip is finished playing.

Remember that ! means NOT, so this line of code can be read as “If the audio
clip is not playing,” which will be true when the intro clip is over.

(5) introMusicIsPlaying = false;