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Godot Steam Audio

Godot

A GDExtension that integrates Valve's Steam Audio SDK into Godot 4.4. Provides real-time acoustic simulation including geometric occlusion, sound transmission through surfaces, distance-based attenuation, room reverb via reflections, and spatial ambisonics rendering. Supports dynamic geometry updates. Currently in alpha with working Linux and Windows builds. Includes basic scene setup nodes and runtime effects processing. Planned features include baked reflection maps for performance optimization and expanded raycasting configuration. The extension wraps Steam Audio's Apache-licensed SDK, which is used in production titles like Counter-Strike 2 and Half-Life: Alyx. Intended to provide feature parity with official Unity and Unreal plugins. Note: the author has stated they are no longer actively maintaining the project and welcome community forks.

libmysofa

Standalone

libmysofa is a C library for reading and processing Head-Related Transfer Function (HRTF) data stored in AES SOFA files conforming to the AES69-2015 standard. It provides functions to load SOFA files, extract HRTF filters for specific spatial coordinates, and convert between Cartesian and spherical coordinate systems. The library handles automatic normalization of HRTF data, nearest-neighbor interpolation for arbitrary listener positions, and efficient caching of multiple SOFA files. It supports both integer and floating-point filter extraction with configurable sample rates and neighbor search parameters. Designed for integration into spatial audio engines and renderers, libmysofa offers both simple and advanced APIs for developers who need direct access to HRTF data without implementing SOFA parsing from scratch.

Omnitone

Standalone

Omnitone is a Web Audio API implementation of ambisonic decoding and binaural rendering. It supports first-order (4-channel) and higher-order ambisonic streams (2nd and 3rd order, up to 16 channels). The library uses native Web Audio nodes for performance-critical processing, ensuring efficient CPU usage. The implementation follows the Google spatial media specification and uses SADIE binaural filters for rendering. It accepts input from HTML media elements or multichannel AudioBufferSourceNodes, with support for dynamic rotation matrices to orient the sound field in response to user interaction or sensor data. Omnitone powers the Resonance Audio SDK for web and provides both ambisonic and bypass rendering modes. The library is designed for browser-based spatial audio applications, VR experiences, and 360-degree video playback. Note: the last release (v1.3.0) was in January 2019, so the project is effectively dormant.

Project Acoustics

Unreal · Unity · Wwise

Project Acoustics is a wave-based acoustics simulation system that bakes acoustic propagation into pre-computed data files. It models occlusion, obstruction, portalling, and reverberation using physics-based wave simulation during an offline baking process, then provides runtime queries for interpolated acoustic parameters. The system uses the Triton engine for voxel-free interpolation and supports multiple ACE files simultaneously. It includes HRTF processing validated through FLEX listening tests published in the Journal of the Acoustic Engineering Society. Runtime performance remains efficient by querying pre-baked simulations rather than computing wave propagation in real-time. Integrations provide spatial reverb, custom impulse responses, and parameter exposure to engine-native systems. The tool handles large worlds through double-precision mesh parsing and supports both middleware and engine-native audio pipelines.