Valve will release a version of its Steam digital distribution service for Mac next month, along with Mac-native versions of its own games, the company confirmed today after days of hints -- and owners of Valve games will have access to both platform versions.
The Source engine, which Valve uses to develop all its internal titles and also licenses to third-party developers, will incorporate OpenGL in addition to DirectX, to allow Mac support for all Source developers.
"We looked at a variety of methods to get our games onto the Mac and in the end decided to go with native versions rather than emulation," said Steam development director John Cook in a statement released ahead of this week's Game Developers Conference in San Francisco.
A current beta version of Steam already uses the multiplatform WebKit as its browser core, replacing its longtime Internet Explorer platform. Many gamers took that as a hint Steam would be expanding to other platforms like Mac or Linux, and the company tacitly acknowledged its plans by releasing a series of teaser images modeled after well-known Apple advertising campaigns.
In recent years, Valve has released new games simultaneously on PC and Xbox 360; the company says it will now expand its core development scope.
"We are treating the Mac as a tier-1 platform, so all of our future games will release simultaneously on Windows, Mac, and the Xbox 360," said Cook. "Updates for the Mac will be available simultaneously with the Windows updates."
Mac and PC users will effectively share a single platform for Valve games. Valve's Steamworks suite of online authentication and game features, which an increasing number of third-parties are using in their own games, will be fully-supported on Mac, and Valve says its server and client code is fully interoperable -- owners of either platform can play in the same multiplayer servers.
With games that support "Steam Play," including Valve's own games, players can install both PC and Mac versions and load up either one on their respective computers. Those games also support cross-platform Steam Cloud use, retaining settings and save games regardless of system.
That means Mac gamers will have access to the ongoing bevy of content Valve makes available for the PC versions of games like Team Fortress 2, which has seen dozens of free updates since it launched in 2007. The company has traditionally been unable to operate similarly on consoles, due to the processes and costs involved with update submissions and certification.
While Valve's back catalogue will be released for Mac in April, the recently-announced Portal 2 will be the studio's first day-one Mac release.
"Checking in code produces a PC build and Mac build at the same time, automatically, so the two platforms are perfectly in lock-step," said Portal 2 lead developer Josh Weier. "We're always playing a native version on the Mac right alongside the PC. This makes it very easy for us and for anyone using Source to do game development for the Mac."
Valve says it has already begun licensing Source and Steamworks for Mac.