Procedural techniques and procedural audio has been used in games almost since the beginning (Fournel 2010), as it was a necessity in the arcade games with limited memory. The trend seemed to disappear when home consoles got increasingly more powerful, but lately, procedural audio has regained some attention – especially in academia. Andy Farnell (2007) defines procedural audio as such “ Procedural audio is non-linear, often synthetic sound, created in real-time according to a set of programmatic rules and live input”.
There are two main approaches to procedural audio (Fournel, 2010): Bottom-up and top-down. In the bottom-up approach, the sound designer examines how the sounds are physically produced, and then write a system to recreate them. This is also known as telelogical modelling. In the top-down approach, the sound designer analysed examples of the sounds she wants to create, then find the adequate synthesis system to emulate them. The top-down approach is also known as ontogenetic modelling. In an interview with N. Varun (2014), Fournel argues that the bottom-up approach is overcomplicated and requires too much knowledge of audio synthesis and audio production mechanisms to be approachable to most sound designers. He then talks in favour of the top-down approach, which he believes could “help creating more convincing sound effects”. He argues that this approach would also be a lot easier to accomplish for most sound designers, and not just for what he calls “a new breed of ‘technical’ sound designers”. Farnell, on the other hand, talks more in favour of the bottom-up approach. According to Farnell (2010), this method allows the sound designer to create sound objects that can be modified in real-time to mimic the unpredictable nature of real world sounds. This approach, however, is still not fully viable, and some critiques would include that the sounds do not resemble real-life sounds, yet. However, both approaches are interesting in that they might be a solution to the ever excisting problem of memory made available for audio in games, and there are some examples of procedural audio in use which are promising.
Sim Cell is an example of procedural audio used in game. Designed by Leonard Paul, the sound and music was created using the visual programming language Pure Data (Paul, 2015). When talking about the generative music for the game, Paul (2015) argues that this system “when combined with synthesis […] allows for the creation of rich and highly adaptive compositions utilizing a small amount of storage space”. Another example is the upcoming 2016 title No Man’s Sky (Hello Games), where both the visual content and the audio will be created using procedural methods. The audio director, Paul Weir, explain that they have created a plug-in which models vocal tracts, and within that the feature of the creature making the sound can be specified. Further these parameters are mapped into the game, and this results in the sound that creature is making.
Barbosa, Alessandro (2015) “No Man’s Sky’s procedural audio is pure musical wizardry” [online]. LazyGamer. Available from: <http://www.lazygamer.net/genre/sim-genre/no-mans-skys-procedural-audio-is-pure-musical-wizardry/> [Accessed 25/10/15]
Farnell, Andy (2007) An introduction to procedural audio and its application in computer games [online]. Obiwannabe. Available from: <http://www.obiwannabe.co.uk/html/papers/proc-audio/proc-audio.html> [Accessed 25/10/15].
Farnell, Andy (2010) Designing Sound. Cambridge, Mass: MIT Press
Fournel, Nicolas (2010) Procedural Audio for Video Games: Are we there yet? [Online]. GDCVault. Available from: <http://gdcvault.com/play/1012645/Procedural-Audio-for-Video-Games> [Accessed 25/10/10]
Nair, Varun (2012) “Procedural Audio: An Interview with Nicolas Fournel” [Online]. Designing Sound. Art and technique of sound design. Available from: <http://designingsound.org/2012/06/procedural-audio-an-interview-with-nicolas-fournel/> [Accessed 26/10/15].
Paul, Leonard (2015) “The Generative Music of Sim Cell” [Online]. AES 56th International Conference: Audio for Games. Available from: http://www.aes.org/e-lib/browse.cfm?elib=17590 [Accessed 30/10/15].
Vachon, Jean-Frederic (2009) “Avoiding Tedium – Fighting Repetition in Game Audio” [Online] 35th International Conference: Audio for Games. Available from: <http://www.aes.org/e-lib/browse.cfm?elib=15158> [Accessed 16/10/15].