On Friday, an Oculus Runtime update blocked a fan-made workaround that had let HTC Vive owners play previously Rift-exclusive software . At the time, Oculus said the update wasn't targeted at the workaround, and was instead trying "to curb piracy and protect games and apps that developers have worked so hard to make." Now, though, Oculus' move has encouraged the patch's developer to break Oculus' digital rights managements entirely, potentially opening VR software up to piracy as well as hardware freedom.

On Saturday, just one day after Oculus' latest Runtime update, Revive developer LibreVR released Revive version 0.5.2. That update gets around Oculus new hardware checks by completely bypassing the DRM for Oculus Dreamdeck and, in theory, any other Unreal Engine game designed for the Rift (a similar workaround for Unity engine games is being worked on). This circumvents the "entitlement check" that confirms a Rift headset is plugged in, but also gets around the ownership check that confirms the software was legitimately purhased through Oculus' Home platform.

Breaking the DRM entirely is now the now the only way to break Oculus' hardware check, LibreVR writes on Reddit. "The problem is that Oculus added the check for the Rift being attached to your PC to the actual DRM. They now use the same function to check that you own the game and that you have the headset," he said. "I can't disable one check without disabling the other one too. Previously these checks were separate and the DRM would only check whether you owned the game."

"I really didn't want to go down this path, but I feel there is no other way," LibreVR wrote on Github. "I still do not support piracy, do not use this library for pirated copies."

Let the arms race commence

LibreVR expanded on those comments in an e-mail interview with Ars Technica. The purported C++ programmer and computer graphics specialist (who didn't share his real name with Ars) said the Revive patch grew out of a philosophical opposition to the idea of tying VR software to a specific headset. "Locking out hardware hurts consumer freedom for all VR users," he told Ars. "It creates an artificial barrier that limits the freedom to choose the headset that you prefer." (Valve's SteamVR platform has built-in support for the Oculus Rift).

Still, LibreVR has some concerns about hacking into purchase-protecting DRM in order to get around the Rift's hardware exclusivity. "I am worried about whether I'm helping piracy by implementing this workaround," he said. "When possible I'd like my workaround to help developers generate more revenue, not hurt that revenue."

On the other hand, LibreVR also added that "pirates will always find a way to work around DRM, [so] I don't think my effort significantly contributed to that."

It doesn't have to be this way, LibreVR stressed to Ars. Oculus' purchase and hardware checks were totally separate as recently as last week, and the original Revive patch didn't support pirated games in any way. Originally, the Revive patch simply replaced calls to Oculus' own runtime with similar calls to the Vive-compatible OpenVR API

This leads to some surprisingly faithful cross-headset compatibility, according to LibreVR: "Native support is always better, because it can optimize for the specific headset. However, the two SDKs are so similar that for most games the translation does not give any significant performance issues." The only real difference, LibreVR says, is that OpenVR lack's Oculus' Asynchronous Time Warp technology, which can smooth out juddering in extremely complex scenes. "But it is best practice not to rely on ATW anyway, so for most games this is fine," LibreVR told us.

Oculus has yet to respond to a request for comment from Ars Technica on this matter, but the company has sent mixed signals regarding its exclusives in the past. In December, Oculus co-founder Palmer Luckey told Reddit "if customers buy a game from us, I don't care if they mod it to run on whatever they want... our goal is not to profit by locking people to only our hardware." But in March, Luckey defended the idea of launching with Rift-exclusive games by telling Ars that "right now, at this stage, of course I want people to buy the Rift [over the competition]." At the same time, Luckey said "our goal is not to lock every piece of software to [the Rift]... eventually there's going to be a lot more headsets to support."

Last July, Luckey explained to Reddit that Rift exclusivity was a way for Oculus to get a return on its investment in the creation of some titles. "The majority of these games would not even exist were we not funding them," he wrote. "It is not like we just paid for exclusivity on existing games. Making high quality VR content is hard enough to do when targeting a single headset, trying to support every single headset on the market with our own content is just not a priority for launch."

While not presuming to speak for Oculus, LibreVR told Ars that "I do think that setting your DRM up to block homebrew developers is never a good idea." As it stands, though, he says the current state of DRM in virtual reality is "the start of an arms race with Oculus that I'm not sure I will win or even want to participate in."