We are excited to announce that with the latest release of Steam Audio[github.com], the complete source code of the Steam Audio SDK is now available as open source. With this release, our goal is to provide more control to developers, which will lead to better experiences for their users, and hopefully valuable contributions back to the wider community of developers using Steam Audio.

This comes after receiving a lot of valuable feedback and contributions from the community to the plugins already available as open source (Unity, Unreal, and FMOD Studio), and we want to bring those same benefits to the core SDK. This will allow developers to tailor the SDK to their needs, and deliver improved experiences to everyone using the technology. We will also continue our ongoing work on Steam Audio, including the release of bug fixes and new features.

The choice of what features we work on is often driven by the needs of internal projects. For instance, during the development of Half-Life: Alyx, we spent a lot of time working on our hybrid reverb and pathing features, which we later released as part of Steam Audio 4.0.0. These priorities might not always align with partner priorities, so we want to remove roadblocks that prevent partners from implementing spatial audio features that require access to the core Steam Audio SDK. As an example, we may be working on fixing a performance issue in Steam Audio affecting an internal project, but a partner may need Steam Audio ported to a console platform. Making the entire SDK available as open source allows partners to manage the port themselves, and optimize it for their needs, while also allowing them to contribute their changes back if desired.

The entire Steam Audio codebase[github.com], including both the SDK and all plugins, is now released under the Apache 2.0 license[choosealicense.com]. This allows developers to use Steam Audio in commercial products, and to modify or redistribute it under their own licensing terms without having to include source code. We welcome contributions from developers who would like to fix bugs or add features to Steam Audio; for more details, see the files https://github.com/ValveSoftware/steam-audio/blob/master/LICENSE.md and https://github.com/ValveSoftware/steam-audio/blob/master/CONTRIBUTING.md in the GitHub repository.

We've just released Steam Audio 4.1.0[valvesoftware.github.io]. This release includes a major update to the Steam Audio Unreal Engine plugin, bringing it up to date with the latest features of the Steam Audio SDK. This is also the first release in which the Unreal Engine plugin is released alongside the other plugins and the core SDK.

The major new features of the Unreal Engine plugin in this release include:

If you are using FMOD Studio as your audio middleware in your Unreal Engine project, the Steam Audio Unreal Engine plugin now works with the Steam Audio FMOD Studio plugin. Events authored in FMOD Studio can use occlusions, reverb, etc. simulated by Steam Audio in Unreal Engine levels.

The Unreal Engine plugin now supports Windows (64-bit Intel), macOS (64-bit Intel), Linux (64-bit Intel), and Android (32-bit ARM, 64-bit ARM, and 32-bit Intel). Note that precompiled macOS binaries are not provided out of the box, but Unreal Engine will automatically compile the plugin for macOS when you open a project that uses the plugin. Precompiled binaries for macOS will be provided in a subsequent patch release.

Geometry can be tagged in any sublevel referenced by a level. Whether the sublevels are loaded automatically along with the main level, or streamed in based on a level streaming volume or any custom logic, Steam Audio will update occlusion, reflections, and reverb automatically.

Any Blueprint class can now be configured to be a Steam Audio dynamic object, and Steam Audio will automatically update occlusion, reflections, and reverb as instances of the Blueprint class move through your levels.

Level geometry (both static and dynamic) as well as baked sound propagation data is now stored in .uasset files that are referenced by Steam Audio components. This simplifies the packaging workflow for your projects.

In addition to the above, this release of the Steam Audio Unreal Engine plugin includes all the latest features of the core Steam Audio SDK, such as pathing, hybrid reverb, and more.

Going forward, updates to the Unreal Engine plugin will continue to be available on GitHub, including source code and pre-built binaries. The version of Steam Audio built into Unreal Engine will be periodically updated, but the latest versions will always be available on GitHub.

For the full release notes for this release, click here[github.com].