On the 10th of August Hello Games released No Man's sky: a sci-fi exploration/survival game that is based on a both brilliant, risky and groundbreaking concept.
Players have in fact to explore a shared universe, with more than 18 quintillion (!) of planets, which are mainly procedurally generated. Basically, instead of creating planets, stars, animals, plants ecc., game developers set the "rules" of the universe and then let the computer create it. This led to a game which is basically alive, and for this reason highly unpredictable, not only because of the player (like many other games), but for the environment too.
From a sonic point of view, the game creates an interesting and inspiring challenge: how can you create sounds and music for something that has so many random variables?
Paul Weir, the audio director, did an astonishing job on both the musical and sound design sides, following the procedural spirit of the game. In particular, in this post I am going to talk about Vocalien, the system created to give a voice to the creatures in the game, and Pulse, the system that moves the music.
Procedural Vocal Cords: Vocalien
How can you give a voice to so many creatures you will probably never meet entirely, without exceeding in memory size and CPU load?
Paul and his team created a system, Vocalien, which basically is a real time synthesis plugin inside the game, based on Wwise. Instead of recording samples and then applying effects on them, it recognizes the trait of the fauna generated by the game to create a proper voice for it.
The system starts with an oscillator, that generates a first sound. This sound is then processed from a system of four different (as Paul called them) "pipes", that are shaped following the size of the creatures in the game, their type (ex cat, horse ecc), the head body ratio and other elements. At the end there is a filter that acts as a mouth, changing the shape of the sound in one more similar to vowels.
A series of states are then used to characterize, change and select these voices further, like hunger, or the night/day cycle.
A crucial part of the system has been it's controller component, as Paul Weir said: "A synthesizer is only a synthesizer, it only makes sense if someone is playing it..either the computer has to play it, or you have to play it... and it's much better if you can play it and then teach the computer what to play". For this reason an interface was built on iPads using Midi Designer Pro, in order to create presets that acted as a seed for the computer, which could create then his own new sounds, starting from those rules.
The result is an always different voice for each creature, that follows his traits and doesn't impact the memory of the game.
Deconstructing Music: Pulse
When making music for video games many challenges come: it has to set the theme and the mood of the game and it has to follow the action of the player, avoiding repetitivity in case of long sessions.
Hello Games contacted Sheffield post rock band 65 Days of Staticto take care of the music. They asked them first to write a classic linear album for the game in their style, which can be listened down here. The music is characterized by big ethereal sounds and dramatic melodic lines, which perfectly follow the concepts of exploration, vastity and loss typical of the game.
The band then worked with Paul Weir to deconstruct the album in little loops, recording also new ones, which have been classified and tagged depending on key, mood and many other elements. These little segments of audio are then loaded in a custom software called Pulse, which combines them following what Wier has called "a scale of interest". If the scale goes up, for example when approaching a building, the music will become more intense with it. The music can react to different parameters: the player engaging in a battle, being underwater or the planet's temperature and ecosystem. Pulse is used also in the cosmic map, changing the music based on which planets the player is looking at.
Thanks to this system, the music is always different and follows the action on the screen seamlessly without sounding too mechanic. "When I hear what other people have done in generative music, and this has been going on for years in academia, they always put the technology first, so musically it's not all that interesting" Weir said "once the system is made, I want to disassociate the science of creating the system from the art of making the music. You shouldn't think of science at that point—it's just a tool."
Although reviews and opinions about New Man's Sky have been contrasting, it has to be said that we are in front of a both ambitious and innovatice title, which introduces new concepts and a new way of making games in the world of triple A titles. On an audio perspective, the influence of No Man's sky goes beyond the purely procedural games, introducing useful tools for the entire industry. Vocalien, for example, gives sound to a lot of gaming elements with low memory footprint, a precious resource in every game. Pulse, then, can be considered a fusion between art and science, being one of the best and more musical examples of adaptive and generative music.