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audio-reverb overview

Reverb on an audio bus - see IAudioSceneComponent.setBusReverb. Every field is optional; resolveAudioReverbSettings fills in the defaults (DEFAULT_AUDIO_REVERB), so every adapter agrees on them.

wet/dry are levels, changed smoothly and cheap to change every frame (fading the reverb in and out is just a series of setBusReverb calls with a changing wet). decay/preDelay/ damping shape the reverb itself: changing one rebuilds it, which is not meant for every frame.

Table of contents

utils

AudioReverbSettings (type alias)

Reverb on an audio bus - see IAudioSceneComponent.setBusReverb. Every field is optional; resolveAudioReverbSettings fills in the defaults (DEFAULT_AUDIO_REVERB), so every adapter agrees on them.

wet/dry are levels, changed smoothly and cheap to change every frame (fading the reverb in and out is just a series of setBusReverb calls with a changing wet). decay/preDelay/ damping shape the reverb itself: changing one rebuilds it, which is not meant for every frame.

Signature

export type AudioReverbSettings = {
  /**
   * Level of the reverberated signal, `>= 0`. Default `0.3`. `0` means no reverb heard: once it
   * has faded out the adapter stops processing it, while keeping the shape (`decay`/`preDelay`/
   * `damping`) ready for the next fade-in.
   */
  wet?: number
  /** Level of the direct (unreverberated) signal, `>= 0`. Default `1`. */
  dry?: number
  /**
   * Reverb time in seconds: how long the tail takes to fall by 60 dB (RT60), `> 0` and `<= 10`.
   * Default `1.5`. Small rooms ~0.3-0.8, halls and tunnels ~1.5-3.
   */
  decay?: number
  /**
   * Seconds between the direct sound and the start of the tail, `0`-`1`. Default `0.02`. Larger
   * values read as a bigger space (the first reflection comes from farther away).
   */
  preDelay?: number
  /**
   * How much faster high frequencies die out than low ones, `0`-`1`. Default `0.5`. `0` keeps the
   * whole tail bright (hard surfaces: concrete, tiles, metal), `1` leaves only a dull rumble at its
   * end (soft, absorbent spaces).
   */
  damping?: number
}

DEFAULT_AUDIO_REVERB

The defaults resolveAudioReverbSettings fills in.

Signature

export declare const DEFAULT_AUDIO_REVERB: Readonly<Required<AudioReverbSettings>>

MAX_AUDIO_REVERB_DECAY

Upper bound of AudioReverbSettings.decay, seconds - the impulse response is held in memory.

Signature

export declare const MAX_AUDIO_REVERB_DECAY: 10

MAX_AUDIO_REVERB_PRE_DELAY

Upper bound of AudioReverbSettings.preDelay, seconds.

Signature

export declare const MAX_AUDIO_REVERB_PRE_DELAY: 1

ResolvedAudioReverbSettings (type alias)

AudioReverbSettings with every default filled in.

Signature

export type ResolvedAudioReverbSettings = Readonly<Required<AudioReverbSettings>>

resolveAudioReverbSettings

Fills in AudioReverbSettings defaults and validates the result - shared by adapters so they all agree on both. Throws a RangeError naming the first field out of its documented range.

Signature

export declare function resolveAudioReverbSettings(settings: AudioReverbSettings): ResolvedAudioReverbSettings

sameAudioReverbShape

Whether two resolved settings describe the same reverb shape (decay/preDelay/damping), i.e. differ in wet/dry at most.

Signature

export declare function sameAudioReverbShape(a: ResolvedAudioReverbSettings, b: ResolvedAudioReverbSettings): boolean