fmod 0.1.0

Unofficial Dart FFI bindings for the FMOD Engine audio middleware, covering the Studio and Core APIs against a user-supplied FMOD SDK.

fmod

Unofficial Dart FFI bindings for the FMOD Engine audio middleware, covering the Studio API (banks, events, parameters, buses) and the Core API (sounds, channels, channel groups, 3D audio).

This is a pure Dart package (no Flutter dependency), usable from Flutter apps, dart run programs, and servers on desktop and mobile targets. FMOD is a trademark of Firelight Technologies Pty Ltd; this package is not affiliated with or endorsed by Firelight.

Status: experimental. The wrapper covers the surface needed for game audio playback; the raw native layer (FmodBindings, structs, the library loader) is exposed through package:fmod/ffi.dart for anything not yet wrapped, and coverage grows as needed. The main package:fmod/fmod.dart entry point is platform-neutral by design, so a web backend over FMOD's HTML5 build can slot in without breaking changes. Verified against FMOD Engine 2.03.14.

FMOD SDK setup

FMOD is proprietary and its license does not permit redistributing the SDK, so this package ships no binaries. To use it

1. Register at fmod.com and download the FMOD Engine SDK for your target platforms (free license tiers are available; check the terms and the attribution requirement for your project).
2. Extract the SDK and set FMOD_SDK_PATH to the extracted root (the directory containing api/). Alternatively set FMOD_LIBRARY_PATH to any directory holding the core and studio dynamic libraries.
3. On macOS, clear the download quarantine from the extracted SDK or the system refuses to load the dylibs (library load disallowed by system policy): xattr -dr com.apple.quarantine "<sdk root>".
4. Build and run with the variable set in the same shell, the runtime loads the libraries straight from the SDK during development.

Platform support: verified on macOS; the Windows and Linux SDK layouts are wired but not yet exercised; iOS and Android are not wired up yet. With FMOD_SDK_PATH set the build hook also bundles the SDK's dynamic libraries into the app as code assets, but the runtime does not consume the bundled copies yet, so a distributable build without the environment variables is not a supported flow yet.

Your app is responsible for FMOD's attribution requirement (the FMOD logo in your credits or splash).

Usage

import 'package:fmod/fmod.dart';
import 'package:vector_math/vector_math.dart';

void main() {
  final system = FmodStudioSystem.create();

  system.loadBankFile('assets/banks/Master.strings.bank');
  system.loadBankFile('assets/banks/Master.bank');

  final event = system.getEvent('event:/Ambience/Country').createInstance();
  event.start();

  // Per frame: position the listener and pump the command queue.
  system.setListenerAttributes(
    position: Vector3.zero(),
    velocity: Vector3.zero(),
    forward: Vector3(0, 0, 1),
    up: Vector3(0, 1, 0),
  );
  system.update();

  // The Core API for raw sounds.
  final sound = system.core.createSound('assets/loop.ogg');
  final channel = system.core.playSound(sound)..volume = 0.8;
  channel.paused = false;
}

The SDK smoke tests run with FMOD_SDK_PATH="<sdk root>" dart test (they skip when the variable is unset, so CI needs no SDK). For headless environments, create the system with output: FmodOutputType.nosound and FMOD mixes without touching an audio device.