Audio Implementation Greats #5: Ambient – The Hills are Alive

In a continued attempt to shed light on some of the best examples of Technical Sound Design in the current generation, I’d like to call attention to several titles that have pushed the envelope when it comes to the art of ambience. The all encompassing experience of “being there” in a game, where the sense of place is encapsulated in the sound of the environment. Stepping beyond the background din of a given location, we’re moving forward towards the players ability to affect the sound of a space by their interaction with it. This can be as simple as turning off a machine that had been emitting a constant loop of activity, or as complex as scaling the dynamics of a crowd dependent on the current artificial intelligence activity in an area.

THE SHACKLES

Despite leaving behind the memory restrictions of previous generation consoles, hearing a single looping ambience throughout a level or area within a game continues to be common – making any recurring distinct elements of the background clearly identifiable when repeated. While these backgrounds, well designed and teaming with character, still contain the potential to keep the player immersed in the game world, anyone who chooses this approach runs the risk of exposing the limitation this technique to the player. Several best practices have evolved and taken root to combat repetition and further lend a sense of randomness to the sound aspect of the game world.

In an article by Nick Peck back in 2004 entitled “Tips for Game Sound Designers”, a case for highlighting ambient elements which vary in time, duration, and position in order to “Generate 5.1 content without full bandwidth sources” was made. This included the idea of a subtly shifting background ambience with randomly placed elements as a solution to static looping soundscape, and presented a way out of the confinements of the locked loop. While likely that this presentation was not the first time a solution was defined, the practice of ambient creation using these methodologies perpetuates today in step with the advancements in available resources and the increased creativity of audio toolsets.

THE LAND OF THE LIVING

The world of Oblivion can be bustling with movement and life or devoid of presence, depending on the circumstances. The feeling of “aliveness” is in no small part shaped by the rich dynamic ambient textures that have been carefully orchestrated by the Bethesda Softworks sound team. Audio Designer Marc Lambert provided some background on their ambient system in a developer diary shortly before launch:

“The team has put together a truly stunning landscape, complete with day/night cycles and dynamic weather. Covering so much ground — literally, in this case — with full audio detail would require a systematic approach, and this is where I really got a lot of help from our programmers and the Elder Scrolls Construction Set [in order to] specify a set of sounds for a defined geographic region of the game, give them time restrictions as well as weather parameters.” – Marc Lambert

In a game where you can spend countless hours collecting herbs and mixing potions in the forest or dungeon crawling while leveling up your character, one of the keys to extending the experience is the idea of non-repetitive activity. If we can help to offset that from a sound perspective by introducing dynamic ambiance it can help offset some of the grind the player experiences when tackling some of the more repetitive and unavoidable tasks.

“[The ambient sound] emphasizes what I think is another strong point in the audio of the game — contrast. The creepy quiet, distant moans and rumbles are a claustrophobic experience compared to the feeling of space and fresh air upon emerging from the dungeon’s entrance into a clear, sunny day. The game’s innumerable subterranean spaces got their sound treatment by hand as opposed to a system-wide method.” – Marc Lambert

Also on the topic of injecting randomness into the soundscape, from a Game Informer interview with Don Veca regarding the ambient sound design of Dead Space:

“Veca told his audio team to make their ambient tracks a little shorter, more vanilla, in order to create audio with fewer effects that would catch a player’s attention when looped. The team then wrote some software Veca calls “the creepy ambi-patch.” This little piece of code would play separate small sounds, gradually changing their pitch and volume as they panned around Dead Space’s 3D environments. The effect worked beautifully, ensuring that every moment of Dead Space’s ambient backgounds were different no matter how long a person explored, or how many times they replayed a section.” – Game Informer

It should come as no surprise that ambience can be used to great effect in communicating the idea of place, either with ties to reality or to the abstract extreme. When you combine the use of soundscapes and level-based tools to apply these types of systems appropriately, the strengths of dynamics and interactivity can be leveraged to create a constantly changing tapestry that maintains a sense of immersion, and creates a personal experience for every player.

THE TOOLS OF THE TRADE

When it came time to design the creative tools used to implement ambiences in Fable II, the sound designers were able to “paint ambient layers” directly onto their maps. In a video development diary, Lionhead audio director Russel Shaw explains:

“I designed a system whereby we could paint ambient layers onto the actual Fable II maps. So that as you’re running through a forest for instance, we painted down a forest theme, and the blending from one ambiance to another is quite important, so the technology was lain down first of all.” – Russel Shaw

In what could be seen as another trend in the current console cycle, enabling the sound designers to handle every aspect of sound and the way it is used by the game is just now becoming common. The ability to implement with little to no programmer involvement outside of the initial system design, setup, and toolset creation is directly in contrast to what had gone before.

In the past, it was not uncommon to create sound assets and deliver them with a set of instructions – how they should be played back – to a programmer. A step removed from the original content creator, the sounds would then need to be programmed into the level – including any parametric or transition information – where the ability to adjust values would be out of reach for the sound designer. It is clearly a benefit to the scope of any discipline to be able to create, implement, and execute a clear vision without a handoff between departments to accomplish the task.

Many of the audio middleware toolsets currently available enable the Sound Designer a high level of control over the way sounds are reproduced. Some include the ability to randomize a sounds 3D position, even going as far to enable the ability to map positional “paths” using a custom interface. This opens up a further level of variation beyond sound files or pitch and volume randomization, and distributes the action across the soundscape in a way that better resembles our experience’s in real life.

As familiarity with these techniques and functionality of available toolsets increases, we can hope for a level of randomness that keeps the player firmly rooted in diversity and appropriateness of the game world. In this way I feel like we are gaining in the art of audio implementation and sound integration – by putting creative tools in the hands of the interactive-minded sound designers and implementation specialists we are paving the way for the ability to simulate living breathing worlds of sound.

THE NAKED CITY

“There are a thousand tales in the naked city” and if you listen closely enough you might be able to hear most of them during the gameplay of Prototype. That is, if you can keep yourself from wreaking havoc among the citizens of New York…which, let’s face it is nearly impossible. While you probably won’t hear all of the stories that the city has to tell, you will be able to hear the changing voice of that city during your progression from introspective lost soul to amped up superman thanks to the attention to detail by Radical’s Sound Department. In a detailed article, Sound Director Scott Morgan details the implementation that gave Protoype’s cityscape it’s voice.

“So we decided to develop a dynamic system for ambient sound so that New York could speak, through its inhabitants, of its current “emotional” state. If the city was in a relatively “normal” state, we would hear the traffic, the pedestrians and the busy sounds of New York that we all know. As panic ensues, so does the voice of the city, with screaming pedestrians and honking horns. If the player guides his character up to a quiet rooftop or the middle of Central Park, the sounds of New York adapt accordingly. As the infected hordes take over, the sounds voice the pain and suffering of the city and its inhabitants. As the story progresses and the city heads towards its darkest hour, its voice dynamically follows – expressing its state as a character in the story, revealing its suffering.” – Scott Morgan

This touches on a diverging point in the creation of ambience: that the sound of the ambient should react to the gameplay and change dynamically based on what’s happening in the environment as a result of player interaction. As we continue to move closer towards realistically representing a model of reality in games, so should our worlds react and be influenced by sound and its effect on these worlds. This was foreshadowed by Crytek’s Christian Shilling during the production of the original Crysis:

“Ambient sound effects were created by marking areas across the map for ambient sounds, with certain areas overlapping or being inside each other, with levels of priority based on the player’s location. ‘Nature should react to the player,’ said Schilling, and so the ambiance also required dynamic behavior, with bird sounds ending when gunshots are fired.” – Christian Schilling

Schilling went on to explain the basic concept and provide additional background when contacted via email:

“Sneaking through nature means you hear birds, insects, animals, wind, water, materials. So everything — the close and the distant sounds of the ambiance. Firing your gun means you hear birds flapping away, and silence. Silence of course means, here, wind, water, materials, but also – and this was the key I believe – distant sounds (distant animals and other noises)…So, after firing your gun, you do hear close noises like soft wind through the leaves or some random crumbling bark of some tree next to you (the close environment), all rather close and crispy, but also the distant layer of the ambiance, warm in the middle frequencies, which may be distant wind, the ocean, distant animals”
In addition to the triggering of various one-shot sounds, various mix decisions are being made behind the scenes in order to further focus on the appropriate sounds – Insuring that the important aspects of sound are communicated to the player.

THE WAY FORWARD

Thankfully, the continuation of work started years ago to diversify the ambient landscape in games and bring variation and randomness to environmental sound is starting to make headway. With standout examples leading the way, and dedicated individuals sharing their processes and reasoning, we can hope to expand on the creative possibilities enabled by toolsets and best practices to create rich sound worlds for players to inhabit. Focusing on these ambient techniques during game development means the player won’t feel inclined to focus the negative aspect of hearing loop point’s while playing – instead, they can marvel at the interaction between their character and the game world, and let it set the tone for their experience.