| # Unity Audio |
|
|
| Unity plays audio through `AudioSource` components that reference an |
| `AudioClip` asset. A single `AudioListener` in the scene is required |
| (usually on the Main Camera). |
|
|
| ## AudioClip |
|
|
| An `AudioClip` is the audio data. Supported formats: WAV (uncompressed, |
| fastest), MP3/Ogg Vorbis (compressed, smaller). Unity imports them and |
| lets you choose compression per-platform in the import settings. |
|
|
| ## AudioSource |
|
|
| ```csharp |
| var src = gameObject.AddComponent<AudioSource>(); |
| src.clip = jumpClip; |
| src.volume = 0.7f; |
| src.pitch = 1.0f; |
| src.loop = false; |
| src.playOnAwake = false; |
| src.spatialBlend = 0.0f; // 0=2D, 1=3D |
| src.Play(); |
| ``` |
|
|
| Important properties: |
|
|
| | Property | Meaning | |
| |-----------------|-----------------------------------------------------------| |
| | `clip` | The AudioClip to play | |
| | `volume` | 0..1 | |
| | `pitch` | Default 1; >1 = higher pitch, <1 = lower | |
| | `loop` | Repeat when the clip ends | |
| | `playOnAwake` | Play automatically when the AudioSource is enabled | |
| | `spatialBlend` | 0=fully 2D, 1=fully 3D (position-based) | |
| | `minDistance` | Within this distance the sound is at full volume (3D) | |
| | `maxDistance` | Beyond this distance the sound is inaudible (3D) | |
| | `rolloffMode` | Logarithmic, Linear, or custom curve (3D falloff) | |
|
|
| ## 3D audio |
|
|
| For positional sounds (footsteps, gunfire, engines), set |
| `spatialBlend = 1.0f`. The volume then depends on the distance between the |
| AudioSource and the AudioListener. |
|
|
| ```csharp |
| src.spatialBlend = 1.0f; |
| src.rolloffMode = AudioRolloffMode.Logarithmic; |
| src.minDistance = 1f; |
| src.maxDistance = 50f; |
| ``` |
|
|
| > Default `maxDistance` is 500 -- way too large for most gameplay. Lower |
| > it to 30-50 for SFX. |
|
|
| ## One-shot SFX |
|
|
| For short sound effects (pickups, gunshots, impacts) use `PlayOneShot`: |
|
|
| ```csharp |
| audioSource.PlayOneShot(clip, volumeScale); |
| ``` |
|
|
| `PlayOneShot` can layer multiple clips on the same AudioSource without |
| cutting each other off. |
|
|
| ## AudioMixer |
|
|
| For volume control and grouping, create an **AudioMixer** asset |
| (`Assets > Create > Audio Mixer`). Expose parameters and control them at |
| runtime: |
|
|
| ```csharp |
| [SerializeField] private AudioMixer mixer; |
| |
| public void SetMasterVolume(float dB) => mixer.SetFloat("MasterVolume", dB); |
| public void SetMusicVolume(float dB) => mixer.SetFloat("MusicVolume", dB); |
| public void SetSfxVolume(float dB) => mixer.SetFloat("SfxVolume", dB); |
| ``` |
|
|
| Convert linear 0..1 to dB: |
|
|
| ```csharp |
| public static float LinearToDB(float linear) => |
| linear <= 0.0001f ? -80f : Mathf.Log10(linear) * 20f; |
| ``` |
|
|
| ## The AudioManager pattern |
|
|
| The generated `AudioManager.cs` is a singleton with two channels |
| (`sfxSource`, `musicSource`). It exposes: |
|
|
| ```csharp |
| AudioManager.Instance.PlaySfx(pickupClip, 1.0f); |
| AudioManager.Instance.PlayMusic(menuMusic); |
| AudioManager.Instance.StopMusic(); |
| AudioManager.Instance.ApplyVolumes(); |
| ``` |
|
|
| `DontDestroyOnLoad` keeps the manager alive across scene loads so music |
| does not restart. |
|
|
| ## AudioListener |
|
|
| * Exactly one `AudioListener` per scene. The Main Camera has one by |
| default; remove it if you add another. |
| * The listener's transform defines "where the player's ears are" for 3D |
| audio panning. |
|
|
| ## Performance |
|
|
| * Pool AudioSources for sounds that play many times per second (machine |
| guns, rain). Reusing one AudioSource and calling `PlayOneShot` is fine |
| up to ~20 simultaneous clips. |
| * Use compressed formats (Vorbis) for music; uncompressed (WAV) for |
| frequent short SFX. |
| * Set `AudioClip.preloadAudioData = true` for short clips and `false` for |
| music that should stream from disk. |
| * Lower `maxDistance` aggressively; large falloff radii cost CPU on 3D |
| sounds. |
|
|
