sentences:  In the same year, LGP released Shadowgrounds which was the first commercial game for Linux using the Nvidia PhysX middleware.In July 2012, game developer and content distributor Valve announced a port of their Source engine for Linux as well as stating their intention to release their Steam digital distribution service for Linux.The potential availability of a Linux Steam client has already attracted other developers to consider porting their titles to Linux, including previously Mac OS only porting houses such as Aspyr Media and Feral Interactive.