Understanding How Wwise Prioritizes Sounds and Motion Objects

The advanced playback settings determine which sounds and motion objects are played at any point in your game. These playback settings are defined at two different levels within Wwise: at the object level in the Actor-Mixer and Interactive Music hierarchies, and at the bus level in the Master-Mixer hierarchy. Because these settings are defined at three different levels within Wwise, a sound, music, or motion object must pass through two separate processes before being played.

The first process occurs at the Actor-Mixer or Interactive Music level. When you define the advanced settings for objects at this level, you are setting a limit that is either global or per game object. If the limit is reached, the priority then determines which objects will be passed to the bus level in the Master-Mixer hierarchy.

The following flowchart shows how Wwise determines which sounds and motion objects within the Actor-Mixer Hierarchy or which music objects within the Interactive Music Hierarchy will be played per game object:

If the new sound, music, or motion object is not killed or sent to virtual voice at the Actor-Mixer or Interactive Music level, it passes to the second process at the Master-Mixer level. At this level, a global playback limit is used to restrict the total number of voices that can pass through the bus at any one time.

The following flowchart shows how Wwise determines which sounds, motion objects, and/or music will be output through a bus.

At this point, the global project limit maximum number of voices determines if sounds are killed or put into virtual voice based on their own virtual voice settings.

[Note] Note

All the properties on the Advanced Settings tab of the Property Editor are absolute properties. For more information on absolute properties and overriding a parent’s properties, refer to Defining Absolute Properties.

Volume Threshold and Virtual Voices

Along with Playback Limit and Playback Priority, Wwise allows you to determine which sound, music, and motion objects will play based on a volume threshold. When the volume level reaches a specified volume threshold or when the number of sounds is over the limit specified in the Playback Limit, the object can do one of the following:

  • Continue to play.

  • Be killed.

  • Be moved into the virtual voice list.

The virtual voice list is a virtual environment where certain parameters of a sound or motion object are monitored by the sound engine, but where no processing occurs. If you select this option, sound, music, and motion objects move from the physical voice to the virtual voice and vice versa based on their volume levels. If the volume returns above the volume threshold or the number of playing sounds goes under the limit of simultaneous playing sounds, the objects automatically move back into the physical voice. For more information on setting the volume threshold, refer to Specifying Volume Thresholds for a Project. For more information on defining the behavior of low-volume sounds and motion objects, refer to Managing Low-Volume Sounds and Motion Objects.