In this chapter, you brought sound to your game environment using a few different methods. Good audio is what holds VR environments together, and the importance of realistic sound in immersion is not to be underestimated.
We began with simple 2D audio, which is fast and easy to implement but really only good for audio scenarios in which location doesn't matter, such as menu sounds. We then modified Unity's Audio Source component in order to spatialize it and create basic stereophonic 3D audio.
Stereophonic audio can help players locate the origin of sounds around them, but it can't be used to determine whether the sound is coming from above or below the player because the "head" in the audio calculation is completely static and the ears are always in the same relative orientation.
We then added another dimension of realism to our simple 3D audio by implementing HRTFs, or head-related transfer functions. HRTFs are only possible with head-mounted devices because they take head/ear rotation...