The Challenge of Creating Audio for Planet Coaster

Using contextual impressions and data gathering to design crowd audio in Planet Coaster. My 2017 talk at the Develop: Conference audio track. Talking about the systems that enable very large crowds to have performant audio, using systems to tackle scaling implementation and of course coasters.

Thanks: Develop Conference | John Broomhall | Tandem Events | Hugh Edwards

Planet Coaster - Audio Showcase Showing Planet Coaster Audio Design Systems in a player created map. Frontend Music
Menu music changes when navigating different pages and transitions into Chorus for loading, then naturally transitions to an outro when loading completes. This adjusts for fast and slow loading platforms alike.

Crowd
Planet Coaster represents crowds in a clever way that prioritises performances over latency and enabling a data driven, accurate representation of thousands of people using impressionism and emitter synced layers.

Coaster
Over 20 layers combine to tell the story of a coaster. From car rattle to wind and track noises. Each layer is data driven using such parameters as speed, acceleration, downforce etc. to achieve a truly unique representation of the coaster that players have build.

In Game Music
Music is carefully mixed so that diegetic sources (rides, placable speakers, shops) can overlap without resulting in cacophony. Player data is used (are they building, engaging with their the game etc.) to find moments where non diegetic music adds to the experience. Sound Architect Audio Review.

"... Let's begin with saying that this is probably one of the best games I've heard in a while. As you build your park, you navigate extensively through menus, selecting and manipulating objects to taste. These menus have their own flavor and intricacy that makes them satisfying to navigate. The level of detail and how clean everything sounds is incredible. The mix on Planet Coaster is phenomenal. Everything sits just right, not too loud and not too soft. If you were to crank the volume up, there isn't a single sound that is jarring or in your face; everything is where it should be ..."

Read the full review written by Derek Brown.

Rollercoaster Audio: Rollercoaster Audio Captured during Public Alpha Phase

Rollercoasters in Planet Coaster are user created and as such, unpredictable in their their behaviour or how they unfold. Audio relies on real-time data and uses speed, acceleration, g-force and to manipulate the many layers that makes up a single ride. Combined the wind, track noises and environmental reflections tell the users coaster story in sound.
Watson Wu arranged a recording of a coaster for us, in a park closed for maintenance. I studied his recording, aligned it to an a on-ride video and recreated the original recording with my own sound design, always mimicing what the recorded coaster sounds like. The simulation informs audio of the angle of a coaster and combined with physics data it produces an accurate sound simulation of the clangs and bangs of mechanical couplings and car interactions while the track is turning, rolling or banking.
To support a wide range of player created coaster builds (from very mild to insanely exciting) we deployed a real time parameter data compressor/limiter (with coder Ian Hawkins) that will use a threshold and an ever increasing compression ratio to set the reported speed of a coaster in wwise. We set the compression curve from 25 to 32 m/s so that all coaster creations sound exciting even if a track is build to go really fast, all the time.

A swooshes and reflection system (created with coder Jon Ashby) is dynamically generating swoosh emitters along the track of a coaster. These emitters playback noise that is volume and pitch modeled on distance to listener. Creating the effect of a "woosh"-by when going past it fast or silence when hardly moving at all. Emitters are placed in real-time to accommodate user-generated content. A sphere test is executed at each side of the coaster, set to collide with terrain and physics meshes only.
Based on distance of intersection, RTPC's (real time parameter controls == data send from the game we can use to manipulate sounds) are used to send part of the coaster audio to specially prepared buses while dampening the direct (dry) signal to simulate reflections. The buses are hard panned to the correct side. This system is runs fast and is a good impressionistic compromise between ray-casting (expensive and more technically correct reflections) or not acknowledging the environment at all.

Larger objects, such as buildings and caves, contribute to the "reflection" system, while smaller object (such as scenery or struts) create swooshes audio. This relatively "simple" system of reflections and swooshes helps ground coasters in their environment and runs fast in a real-time, user generated environment.

Embracing impressionism
Using data to paint context aware crowds that cost the same to render, regardless of size From the AudioKinetic Wwise article on Planet Coaster crowd managment. Published June 27th 2017 - A detailed description of the crowd audio system created specifically for Planet Coaster. The main feature of the implementation is that it creates an impression of large crowds using a fixed amount of time per frame. A system that scales with the size of a park, without asking for more resources. We call this conextual mixing and using data to drive background to foreground layers.

Please note that this system still forms the basis of Frontier Emitter Managment system, but has since been expanded greatly. See the article on Jurassic World Evolution and the 2022 GDC talk for a more recent breakdown.

Part 1. Scaling Ambition
Part 2. The Crowd Soundbox System
Part 3. Additional Layers

From the AudioKinetic Wwise article on Planet Coaster crowd managment.

Community Livestream: Planet Coaster Audio 15th of February 2017 - Planet Coaster community stream focused on game audio with audio programmer Jon Ashby and hosted by community manager Bo Marit. Topics include: Dynamic music system which adapts to interaction, play-style and loading times. The Music system also 'knows' what the player is doing and will create a music playlist accordingly. Solutions for obstruction / occlusion in a user generated environment. Planet Coaster's context based mixing data that exchanges pre-placed emitters to drive audio with a more dynamic approach. Finally there is the sound of roller coasters in all their isolated layers!

While the stream was primary aimed at Planet Coaster's community, it does delve deeper into the technical and creative solutions of the audio.

Developer Diary: Audio 17th of August - Planet Coaster Audio Development Diary. Check out our latest Planet Coaster Dev Diary. This installment highlights the staggering detail that goes into making the Planet Coaster audio. Creating a rich and immersive environment that brings your park to life. Reviews and Accolades LGR Audio Review ... a game crafted with care. The interface feels familiar yet modern. The graphics look promising. And there is this soothing soundtrack by Jim Guthrie and JJ Ypsen playing in the background which instills a sense of focus and calm ... Planet Coaster is also just a gorgeous game, which of course it isn't necessary for to the business side of things but it is a great plus for a 3d park like this.

The Sound design is also right on point, giving you all the screams, coaster whooshes, crowd chatter and rickety mechanical audio cues ones needs to suspend disbelief. You can also customize this further with ambient sound generates and music customisation. And yes this also lets you drop in your own music tracks to fine-tune your parks audio visual theme.

Reviews and Accolades Game Spot Review ... one of my favourite things about the game, so far, that I have discovered is the sound design ... Joey on GameSpot's Planet Coaster Live Stream ... © 2023 Frontier Developments, plc. All rights reserved. Frontier and the Frontier Developments logo are trademarks or registered trademarks of Frontier Developments, plc
All other trademarks and copyright are acknowledged as the property of their respective owners.