sound_recipes 0.5.0-dev

Game sounds with no audio files: write a recipe, it is synthesised to WAV at start-up and played through flutter_soloud. A stock set by material, and music crossfaded by context.

sound_recipes

Game audio with no audio files: a sound is a recipe — a length and a function of time — rendered to WAV when the game starts and played through flutter_soloud. Comes with a stock set of sounds for every material, and music that crossfades by mood.

Nothing here is specific to voxels, or to any genre: it is one file of synthesis, a bank and a player.

Status: 0.5.0-dev, beta. The API can still change.

Features

• SoundRecipe + renderWav: a sound is a length and a waveform function.
• StockSounds: break_, place_ and step_ for every SoundFamily, step_sand and step_snow, plus hit, hurt, pickup, explode and more.
• SoundBank: plays sounds by name, from recipes or asset files.
• AudioDevice: the one audio device every bank shares, opened by the first and closed after the last.
• SoundPlayer / SilentSounds: play through an interface, so tests and servers stay silent.
• MusicScore / StockMusic: background music synthesised from notes, six stock loops.
• MusicDirector: one track per mood, crossfaded; a file when the app bundles it, else its recipe.

Install

dependencies:
  sound_recipes: ^0.5.0-dev

Dart SDK ^3.13.0. Needs Flutter (it plays through flutter_soloud).

Usage

1. Make a bank of the stock sounds, plus your own if you like.

   final bank = SoundBank(recipes: {
     ...StockSounds.all,
     'chime': SoundRecipe(0.5, (t, p, rng) => math.sin(t * 880 * math.pi * 2) * (1 - p) * 0.4),
   });
   

2. Open the device once, at start-up. It returns false where there is no audio, and the bank then stays silent. Every bank holds the one AudioDevice, and dispose lets go of it, so the device closes only after the last bank is disposed. Code that plays through SoLoud itself holds the device the same way, with AudioDevice.instance.acquire() and release().

   WidgetsFlutterBinding.ensureInitialized();
   await bank.init();
   

3. Play by name. volumeDb 0 is full and -6 is about half.

   bank.play('break_${SoundFamily.stone}', volumeDb: -3);
   

4. Music (optional): a mood maps to a file, a recipe, or both — the file plays when the app bundles it, the recipe until then. setMood('night') crossfades.

   final music = MusicDirector(
     {'day': 'assets/music/day.mp3', 'night': 'assets/music/night.mp3'},
     recipes: {'day': StockMusic.pastoral.toRecipe(), 'night': StockMusic.frozen.toRecipe()},
   );
   await music.setMood('day');
   

5. In tests, pass a SilentSounds wherever a SoundPlayer is asked for, and set AudioDevice.instance to a device of your own, so no test opens SoLoud:

   AudioDevice.instance = AudioDevice(open: () async => false, close: () async {});
   

Example

example/main.dart is a sound board: one button for each sound. Copy it into a Flutter app's lib/main.dart and flutter run.