ARCore Road - Motion Tracking 3D Sound Field (4)

上节 We have implemented 3D sound with Resonance Audio SDK, which is just the simplest feature of Resonance Audio, Resonant Audio (Resonance Audio) provides far more advanced functional features than the examples, especially the parameters of the simulated room, which can simulate many real-world characteristics in life. This section mainly provides a more detailed understanding of the Room parameters and API.

一,Room effects

As shown in the above figure, the Room property mainly includes Surface Materials, Reflectivity, Reverb Properties, and Size.

1、Surface materials

The six acoustic surfaces of the Room can be assigned different acoustic materials. Resonance Audio provides 23 different materials. We can directly select the acoustic materials of the city. Each acoustic material is defined. Sound absorption or reflectivity at different frequencies. For example, Heavy Curtain absorbs high frequency parts, which provide a room for a drier, warmer sound. Polished Concrete reflects more of the sound energy at all frequencies, resulting in brighter and more echogenic room characteristics.


This parameter is used to adjust the early reflection intensity of the sound source in the Resonance Audio Room so that the user can have a rough impression of the size and shape of the room around them. For example, reduce the value of this parameter to simulate the sound of a restricted small space, and increase this value to simulate the sound of an open space.

3、Reverb properties

These parameters affect the late reverberation of the Resonance Audio Room. It mainly includes the following three parameters: Reverb GainThis parameter is used to adjust the reverberation gain of the room effect. This reverberation gain is not directly Sound waves from the sound source. You can use this parameter to adjust the "thickness" or "thinness" of the mixed sound. For example, if you want to make the room reverberate weaker, adjust Reverb Gain to make the sound more "smooth". Reverb BrightnessReverb Brightness is used to adjust the amount of low or high frequencies in the reverb. The Resonance Audio Room can provide different reverberation attenuation rates at different frequencies. The wall material of the Room is different for audio absorption and reflectivity at different frequencies, just like in a real room. This parameter can be used to adjust the fill level of the room sound. For example, reducing the reverberation brightness gives a room fuller impression and simulates the sound of a room containing many objects or people. Reverb TimeReverb Time is used to adjust the length of the reverb, which is the decay time of the reverb. This value is the multiplier of the reverberation time calculated from the surface material and room size specified by the Resonance Audio Room. This parameter can be used to acoustically adjust the size of the simulated room.

4、Room size

Use the x, y, and z parameters to set the size of the Resonance Audio Room in meters. The room size affects the room sound effect. This size also sets the sound boundary, triggers the room sound effect when the user enters the range, or smoothly switches from one Resonance Audio Room to another.

二, Resonance Audio API

Resonance Audio provides the main API classes as follows:

ResonanceAudio This is Resonance Audio The main class, which is responsible for the interaction of Resonance Audio with the operating system and hardware.
ResonanceAudioAcousticMesh This class is used to process Mesh, save copy style information of mesh filter or terrain, and surface material assigned to triangle.
ResonanceAudioListener Enhancements to Unity AudioListener provide more advanced 3D sound field adjustment parameters.
ResonanceAudioMaterialMapper Resonance Audio material mapper is a programmable object that handles the mapping of GUIDs to surface materials (these materials define the acoustic properties of the surface).
ResonanceAudioMaterialMapperUpdater Resonance Audio material mapper updater
ResonanceAudioReverbProbe Resonance Audio Reverberation Probe, as a sampling point for sound effects, this sample point emits rays to the surrounding environment to sense the acoustic properties of the surrounding environment and use this information to calculate the reverb sound. .
ResonanceAudioRoom 模拟 room, use this simulation room to simulate a real sound environment.
ResonanceAudioRoomManager Simulated room management class, manages the 3D sound field of the simulated room.
SurfaceMaterialDictionary A serializable dictionary class that is responsible for mapping from surface textures to GUIDs.
ResonanceAudioSource Enhancements to Unity AudioSource provide more advanced 3D sound field adjustment parameters.

In addition, Resonance Audio technology also provides Reverb baking for sound. Just like baking light, you can directly paste the sound characteristics into the environment by setting the probe. Eliminate real-time audio processing and reduce processor stress.