Half-Life 2 now has a virtual reality mod that adds head and gun tracking, and the mod's creator says he will support the Oculus Rift headset once he receives his developer unit.
The creator, Nathan Andrews, implemented his mod with a modified Sony HMZ-T1 3D headset, which does not offer native head tracking. Instead, he used a Hillcrest sensor for head tracking, and taped another one to a wireless Top Shot Elite gun controller to track the weapon's movements. According to Andrews, the trackers are the same ones John Carmack used in demos of Doom 3: BFG Edition with an early Oculus Rift prototype.
"Once the official Rift [APIs] are available I'll integrate them," he said in the description for the video above.
The mod works with Half-Life 2, Half-Life 2: Episode One and Half-Life 2: Episode Two, as well as the Lost Coast extra level and "tons of [user-generated] maps," for approximately 70 hours' worth of content, according to Andrews. Because the gun tracking is independent of the head tracking, the mod can still be played with a regular controller if users don't want to bother with the gun tracking.
In a Reddit AMA, Andrews said neither he nor his wife experienced any nausea from playing the mod, although he noted that motion sickness has never been an issue for him and that his wife only tested slower gameplay segments. He also said that work on the mod was "almost all software," since the Hillcrest sensors were easy to install.