How To Create Foley For Games
What Is Foley?
Foley is all about bringing the objects and characters to life, and grounding them in the world by performing their movements and actions.
Once again, the line is blurred for what exactly is classified as Foley and what isn’t, so it’s up to the various audio disciplines to communicate this to each other. The umbrella of the term covers everything from footsteps, gear, equipment, and cloth movement, to the handling of props like guns, doors, magic wands, or horse carriages.
There are entire outsourcing companies dedicated to the art and craft of Foley. They work in specially-built studios that are optimised to perform, record, and edit Foley for linear and interactive media. These Foley studios are fitted with floors that have various surfaces, as well as storage rooms full of shoes and other props which allow the Foley artists to perform all kinds of different sounds.
I recommend reading this short overview of the topic: https://www.masterclass.com/articles/film-101-understanding-foley-sound-and-why-foley-sound-is-important#what-do-foley-artists-do
Here you can see Foley in action with this great re-design of Kratos from God Of War: https://youtu.be/1Vi8L_eAVUM
Why Is It Important?
Foley adds weight to the player's actions, making them satisfying and believable. As Steve Whetman says in his GDC talk about the Foley of Gears of War, “You can think of Foley as live sound design where you’re building up layers of texture”.
It can also inform us about our environment like hearing the crunch of glass breaking beneath the player's feet as they walk past a shattered window, or give us spatial information such as the position of nearby players or NPCs - for example, listening for other players’ footsteps in an FPS like CS:GO.
Here are some excellent short videos looking at the Foley in video games:
Foley recording sessions from League Of Legends: https://youtu.be/i7rCfLtQNX4
The Foley of Batman: Arkham City: https://youtu.be/g5IMQ12hI3w
Sunset Overdrive’s Foley system: https://youtu.be/8KdLMM8ZI5Y
How Is Foley Made?
Foley is created by using shoes, clothes, props, surfaces, and various other materials and contraptions to perform sounds. These are then recorded into the DAW, edited, processed, and synced to the visuals.
Game developers usually either have their own Foley recording facilities or outsource the Foley to dedicated outsourcing studios. However, you can easily record high-quality Foley on a budget at home by following these tips:
Record in a quiet space!
Foley sounds are often very soft and subtle, which means you’ll have to set the gain quite high on your recording gear, and as a result, will capture some unwanted sounds in the process.
You can avoid this by recording in a quiet space, which is of course easier said than done. If you’re in a busy city then I recommend recording at night when there are fewer cars and exterior sounds that can bleed into the recording.
Additionally, you can create a little Foley booth by using the corner of a room or half a wardrobe and placing absorbent materials like acoustic foam, pillows, and blankets inside and around it.
Get the right sound!
Before you press record, it’s a good idea to put on your headphones and listen to the sound you’re getting. You can then adjust where the microphone is placed as well as the gain to get a nice and clean recording.
Get creative!
Foley is all about creativity and experimentation - the sound of rain, for example, can be created by recording sizzling bacon, bones cracking from snapping celery and other vegetables, and swords from spatulas, knives, and baking trays.
Try things out and listen carefully, because you never know what will sound good. Additionally, you can build props, create makeshift Foley pits & experiment with different recording techniques like putting the microphone inside of a helmet to create a dampened sound.
Clean up your recordings!
Even if you record at night and put covers in front of your windows, you will likely end up with a little bit of noise and some unwanted frequencies. This is where plugins like iZotope RX, as well as simple EQ and noise gates, can come in handy to clean up your sounds.
Layer your sounds!
You probably don’t have a full suit of medieval armour laying around at home, but you probably do have various metal objects that might sound similar. By recording a bunch of different smaller props and layering them together in your DAW, you can get to a believable end result that will convince the player it’s the real deal.
Build a mental Foley map!
You can do this by simply listening to your environment and playing around with various objects and props. Over time you’ll create a sound lexicon in your head that you’ll be able to fall back on.
Foley Editing
Foley editing is a huge but underrated part of the Foley creation process.
Here is an excellent guide by Yuri Pridachin where he shares his insights into the craft: https://www.asoundeffect.com/ultimate-foley-editing-guide/
If you’ve ever wondered what the inside of a Foley studio looks like, then check out this tour of Pinewood Studios: https://youtu.be/CfwDLONo7nI
Foley Implementation (Technical Sound Designer)
Footsteps (FTS)
A very common method for implementing footsteps is through animation tagging (the same principle as we covered in the Sound Effects chapter).
With the help of a programmer, we can set up a system that detects what kind of surface the player is walking on. This allows us to then switch the footstep sound to match the surface (example: the player walks on dirt = dirt footsteps play, the player walks on grass = grass footsteps play).
If we want to add even more realism and variety we could split the footsteps into heel and toe layers and randomise the selection, as well as split them into different shoe types. We could also add some more detail by introducing additional layers that play on top of the footsteps like gravel, twigs, debris, glass or wood creaks to name a few.
Here is a great talk from Bjørn Jacobsen on the footstep system in Detroit: Become Human: https://youtu.be/2iKcJ0PnEvM
Movement (MVMNT)
Cloth and equipment Foley can be implemented in a number of different ways but there are two that are used a lot:
Animation tagging
The same as with footsteps, where each different animation has a number of tags that trigger cloth sounds.
Velocity & Acceleration
In this method the game engine calculates the speed/acceleration of the player character and gives us this value as a number. We can then use this number to trigger the Foley if it’s above a certain threshold (for example: if acceleration > 0.2 then play the Foley loop). Additionally, we can use that same number to automate the volume of the Foley, so that the faster the player moves the louder the Foley will be. If the player is sneaking or walking the Foley will be quiet, but if they are running or fighting the Foley will be louder.
Here is a short example clip of this system in action from the game A Plague Tale: Innocence: https://youtu.be/HLikRVSxUWk?t=558
Specifics (SPFX) / Spot Effects (SPOTFX)
Specifics, also known as spot effects, are one of the many names given to the category of props. It’s a very tricky category as there is a large range of props that the player can carry, interact with and handle, including actions like pickups, throws and drops on various surfaces.
Carrying props usually uses the same or a similar system to the cloth system (using velocity and acceleration) mentioned above, with the option to swap in and out props like swords and guns depending on what the player is carrying with them.
Pickups are pretty easy as they can simply be tied to a code hook that tells the sound to play when the player picks up the item. Dropping and breaking are often done via collision detection, meaning that if the object hits another surface, player, NPC or another object it registers that and triggers the appropriate impact sound.
Additionally, we can set a threshold that means the sound will only play if the impact was above a certain velocity. This is important so we don’t get huge numbers of sounds playing on top of each other whenever an object falls to the floor and rolls or bounces. We can also play different samples based on the velocity, allowing us to create more realistic-sounding Foley.
Advanced Learning Resources
If you want to dive deeper into this topic then I recommend you check out the following articles, interviews and videos:
This is an incredibly insightful video on how the Foley for Alien: Isolation and Gears Of War was created: https://youtu.be/_gwvImPrkbw
The “Vanity System” (Foley system) of Sunset Overdrive: https://youtu.be/6ZFTe2lsYto?t=1642
The sound of The Last Of Us Part II (also covering the Foley): https://www.asoundeffect.com/the-last-of-us-part-ii-sound/
How Pierre-Marie Blind created an immense procedural Foley system using Wwise: https://blog.audiokinetic.com/12-days-of-interactive-foley-design/
Here is a cool breakdown of how Ali Tocher created and implemented swimming Foley for I Am Fish: https://blog.audiokinetic.com/behind-the-sound-of-i-am-fish/
