Audio Volumes: The Legacy Approach
Audio designers can use the legacy Audio Volume system to define a spatialized area in the level where effects are applied to overlapping sound sources. These effects include Reverb effects, Submix effects, and can emulate Occlusion on a sound.
If you want to add a Reverb Effect to a specific room in the Level, then you can place an Audio Volume Actor that matches the room's dimensions and add the Reverb effect. This will impact the sound sources located inside that Audio Volume. Additionally, this can influence how other audio effects outside of the Audio Volume may sound to the listener.
The current system can present a challenge to audio designers, as each Audio Volume's functionality is fixed at runtime. This means that Audio Volumes cannot be extended or customized without modifying the engine code.
Audio Volumes can present a workflow challenge as each Volume requires a separate Actor in the Level. This makes the system harder to integrate with other Gameplay features and therefore cannot easily share data with other Actors.
Audio Gameplay Volumes: The Next Generation Approach
Audio Gameplay Volumes are the next-generation approach to Audio Volumes in Unreal Engine. This system replaces the legacy system and leverages a component and plugin architecture to address many of the challenges of the legacy approach. The new system also offers more flexibility to developers and audio designers.
Component-Based Architecture
The Audio Gameplay Volumes are designed using a modular component approach. Individual behavior components can be added to each Volume. Each component contains configurable behavior for when a listener enters and exits the Volume. Audio designers can combine different components to create custom functionality in a modular way.
The Audio Gameplay Volumes include components that provide behaviors such as Volume Attenuation, Low Pass Filter, and Submix Send.
Extensible
The Audio Gameplay Volume plugin can be enabled or disabled based on project needs. Additionally, developers can create third-party plugins that can extend the functionality by adding new components using the provided API.
Improved Workflow
In many projects, audio implementation tends to happen toward the end of the production cycle. This can make it challenging to implement a robust audio system that works seamlessly with other Gameplay systems. The Audio Gameplay Volumes take this into consideration and provide audio designers the capability to attach Audio Gameplay Volume components to any Actor in the Level.
Audio Gameplay Volumes can integrate with other Gameplay features in Unreal Engine, and can share data easily with other Actors in the Level.
The user interface has also been streamlined compared to the legacy system to make it more intuitive to audio designers.
Improved Integration
Audio Gameplay Volumes offer deep integration with Blueprints to give audio designers flexibility in how they want to implement the system. Volumes can be placed directly in the Level as stand-alone Actors, or can be added as components to any Actor Blueprint.
Audio designers can also implement custom collision checks within Blueprint Actors to simulate when a player enters or exits the Volume, without requiring any adjustments of a physical volume in the level. This removes the necessity of creating complex shapes in the Level that need fine-tuning every time there is a change.
Improved Performance
Collision tests and Volume processing have been moved out of the game thread and into the audio thread. This results in significant improvements to performance and allows developers to extend the system without worrying about thread safety.