Mini-Demo: Positional Audio

We revealed a glimpse of our first audio assets in our last milestone update. We wanted to show you a little tech demo of some of what we're done beyond just that. Be sure you have a stereo device before listening to this! So that you just get to listen, I won't be talking over this one.

Positional audio is the notion of two or three dimensional audio that implies it's coming from a position in space. If we want the player to observe an object coming from their left, we will play the sound more out of the left channel. We can also optionally attenuate the sound, dropping its volume as the source of the sound gets further away from the listener.

Both of these are really cool tools for adding audio depth to a scene because we can effectively add more audio without it all blaring from the middle of the screen and at full volume. Think of it as adding additional audio information! In Melee, for example, we might want to add some subtle texture like missiles expiring, but the further away from you they are, the less important they ought to be compared to the critical information of a missile or laser that's going to spell your doom if you waltz into it. In The Ur-Quan Masters, ship audio was full-blast all the time, but we wanted to see what else we could create.

This video shows both the directional and the attenuation behaviors in action as part of our first test, and we're pretty happy with them! We weren't sure how well the directional aspect would work with Melee since the camera wraps around, but it's not as jarring as we thought it might be. For attenuation, most games work based off of a simple distance calculation, but since Melee is so much about what's in view or out of view and the zoom of the camera changes constantly, we built a custom approach that drops the volume of certain sounds the further they are out of the view frustum (though Melee technically uses an orthographic camera and is always a rectangle, I just really wanted to write frustum).

All of these properties can be tuned on a per-sound basis, which will let us make really critical audio information front and center, while letting us layer in subtler or more dynamic sounds as desired. There's also the beginning of an experiment with ship thruster sounds happening which still needs plenty of polish.

We hope you enjoy hearing the beginnings of what Melee will sound like and that you find many everyday uses for the word frustum.