A few days ago we speculated how code discovered in the Steam Play Git could refer to game compatibility across different operating systems – and it looks like Steam has just announced a new Steam Play version that allows Linux gamers to play Windows-based games on their Linux machine, utilizing Valve’s new Proton, a Wine-based project.
Proton is currently open-source on GitHub, and the source repository does in fact confirm that DXVK is being used for the Direct3D on Vulkan support – it seems Valve has been employing its developer as well as a few other engagements.
What this Proton project does is allow Windows games without a native Linux version available to be installed and launched directly from within the Steam client, complete with native Steamworks and OpenVR support. Furthermore, DirectX 11 and 12 implementations are now entirely based on Vulkan, which has resulted in overall improved game compatibility and lowered performance impact in various testing benchmarks.
Fullscreen support for games has also been improved – fullscreen games will now be seamlessly stretched to the user’s display, without interfering with the native monitor resolution or requiring the use of a virtual desktop – a significant improvement for full-screen gaming on Linux.
Additionally, performance for multi-threaded games that take advantage of multiple CPU core threads has been greatly improved over the vanilla Wine, so game performance should be greatly enhanced in titles that use multi-threading.
Finally, Valve has improved game controller support (for controllers that are supported by Steam, in any case) – this would typically be XInput and DInput type controllers, though XInput is much more popular in a majority of games.
As of right now, the Windows games being supported with this new Steam Play beta launch are QUAKE, Tropico 4, Star Wars: Battlefront 2, DOOM, DOOM VFR, Payday: The Heist, STALKER: Shadow of Chernobyl, and a handful of other popular titles. As Valve continues to test and update this Proton project, they will add more to the list of supported games. In this scenario, we’re imagining that the most popular titles will receive support first – its unlikely that the entirety of Steam’s catalogue will become available on this Steam Play Proton project.
In any case, it will be interesting to follow development, as many wonderful things are being accomplished with Intel and AMD drivers for Linux in recent months, as well as all of the work being done on the Linux 4.19 kernel.
For the full list of currently supported games and additional release notes, see the announcement post by Valve.