All of the recent Virtual Reality buzz being discussed in the media has been massively focused on the war between mainly the Oculus Rift and the HTC Vive; maybe with a little Samsung Gear VR thrown in here and there.

All throughout the war between the two dominating behemoths of Virtual Reality, there’s been a mysterious stranger lurking in the shadows, unbeknownst to most of us including the more tech-savvy and developer minded of us. It goes by the name of OSVR HDK. Even being a game developer myself, I was unaware of this headset’s existence until I happened upon a post in the Unity 3D forums where someone mentioned this headset as a cheaper alternative should you be open to compromising.

It was Sensics that got the ball rolling with OSVR, eventually bringing onboard PC Gaming Hardware specialists Razer to initiate an open-source VR device platform which they call the OSVR HDK (that’s Open Source Virtual Reality Hacker Development Kit). The two companies began formally collaborating in late 2013, as both had been showing signs of interest for VR, and it was just a case of finding the right partners to bring a VR concept to the table. Razer is more known for PC accessories and high performance gaming hardware inputs than it is for anything else, but over the last few years, it’s begun to open up new avenues of exploration for the company’s product portfolio, by delving into the PC gaming laptop market with their super-thin and light ultrabook, the Razer Blade Stealth. On top of this, things such as the Razer Core, which is an enclosure case to store an external desktop graphics card, and by using the Thunderbolt USB standard, is capable of adding the graphics card encased as a usable piece of hardware for any laptop supporting this standard; including their Razer Blade Stealth ultrabook/laptop. Essentially, this means anyone can use a desktop graphics card to power their laptop. One important thing to note, is that Razer is allowing an Open-Source style of use for any laptop manufacturer that wishes to use their Razer Core module, to allow their own laptops to use external graphics cards encased in the Core. Very generous on Razer’s part, since they could have easily have patented the technology for proprietary use.

Despite the base hardware kit being sold and supported by Razer, there’s no branding of any kind on the headset from either company, other than the prominent letters of “OSVR”. This stands for Open Source Virtual Reality, and is a movement started by Sensics and Razer to create a more open and accessible marketplace for virtual reality headset vendors, and software developers. Whilst Razer produce and sell the base development kit headset, they maintain a stance along with Sensics that what they have created is a separate entity away from themselves. This is a platform for the community and developers to maintain, develop, and make their own. Sensics/Razer simply curate and manage it from a promotional standpoint, helping to push the platform and further support it. Much like Razer’s attitude to the Razer Core technology being accessible to anyone, their approach to virtual reality is to allow anyone to create a piece of software, that can communicate with any headset, regardless of manufacturer/vendor. Currently, the climate is closed to the target headset’s platform that delivers its experience. Video game and software developers who want to create a virtual reality experience must develop and tailor their applications to a specific type of headset. Where the rotational and positional data of one headset might send a certain style of formatted data to the PC, another headset will use a differently styled format of data, or might not even transmit that data at all. In a similar way to how the USA and the UK format their dates differently between month-day-year and day-month-year, headsets send their data in different formats and send different types of data that others might not be able to or choose not to. There’s also things like the properties of the headsets to consider, such as their field of view, the optic lenses used, the size and resolution of the screen as well as its aspect ratio; there’s a plethora of properties to keep track of and match your software to the specifications of.




Enter OSVR. Software that allows anyone to simply write their application using functions/methods within the OSVR library to execute commands or read data, and OSVR will query the device from its extensive library of supported headsets, and return data or run commands in a universal manner which is supported by software that utilises the OSVR environment. Basically, instead of talking and dealing with each individual headset and having to learn each individual piece of hardware from a programming perspective, the software developer now only deals with OSVR, which already knows how to communicate with a wide variety of headset devices, thus enabling a developer to write their software once with only one standard in mind, and OSVR will make sure that translates to every device it supports.

Seems like a no-brainer right? Like how every computer mouse might be designed differently with various smoothing technologies and other marketing buzz-words, but at the end of the day, every mouse behaves and operates the same right? Well, things like keyboards and mice are universally connected in terms of their behaviour, because Microsoft has included libraries within its operating system, for developers to use with their devices. Well, currently virtual reality doesn’t do this properly as of yet. Valve have modified their SteamVR platform in such a way that it is now referred to as OpenVR. They allow a variety of headsets to be used within a SteamVR environment, and no longer just the HTC Vive device. Whilst SteamVR’s OpenVR approach is commendable, since Valve could have gone in the same direction as Oculus with their Rift, and created a closed platform that only works with software specifically made with the Rift in mind, they eventually chose to adopt the same open approach as the OSVR standard.

It’s likely that OpenVR (SteamVR) will replace OSVR, because the HTC Vive is the more popular and high-demand headset device currently in the early days of virtual reality. However, we might have a system where the two could merge, where Valve adopts the OSVR environment (since it’s open-source and free for anyone to merge within their existing frameworks). Truthfully, that’s what OSVR is hoping for. They want developers to take the OSVR framework, and make their own versions of it. The idea is that neither Razer or Sensics own this software; it’s there for people to improve, change, and redesign as they see fit. Both companies want an open and collaborative effort for virtual reality hardware support, especially as Razer being a hardware accessory vendor, since if the OSVR initiative wins, Razer wins by selling their accessories for a wide range of devices. Alternatively, both SteamVR/OpenVR and OSVR could both exist as independent frameworks, and it would be easy enough for developers to simply support both, switching between a SteamVR/OpenVR version of the software, and the OSVR version.

But that’s enough talk about the software side of things; let’s get talking about the hardware. The OSVR HDK is a lightweight, and modular piece of kit that approaches the hardware side of things much like the OSVR software. The headset can be pulled apart, modified, and have parts swapped out for others, such as the screen, optics, eyepiece foam, and the entire encasing itself. The idea is that rather than spend a large amount of money upgrading to a new and improved headset in a year or so, the HDK is upgradable in small bite-size parts. Currently the screen is a standard 1920×1080 pixel display, but if a 1440p screen was to come out or even a 4K display, you could swap them around for the improved one, and only pay for that one part. The higher resolution might require a new controller board (PCB) inside the unit, which will also be replaceable. Maybe better optics are created, so swap them out too! Whatever improvements are made from the headset, or maybe a particular company brings its own branded version of casing or other piece of hardware, you can swap things around to suit your needs and budget. Much like you build a PC with various parts and pieces of hardware from different companies you trust or build a relationship with, you can customise and brand your own headset with different parts. Currently however, the headset is standard with the default parts, and only a few upgradeable pieces are available from the OSVR website, but Razer isn’t stopping anyone from developing their own custom parts for the headsets in the future, and no royalties are owed to Sensics or Razer, as the device design plans are accessible to anyone who requests them from the website. You’ll even be able to 3D print your own headset as an individual!

My experience has been quite limited as of the last month in using it. Only a few games are playable with the headset, most made with Unity3D or Unreal Engine 4, but these are mostly demos or indie games with no real potential as of yet. The only real experience I’ve had in a gameplay setting, has been Half Life 2. Half Life 2 uses the SteamVR framework, which supports the OSVR HDK as a device. The great thing about playing a game like Half Life 2 is that it’s a low requirement game for a modern machine, and the 1080p display on the OSVR HDK means that framerates are well above the industry recommendation of 90 frames per second or higher on virtual reality experiences (though the HDK screen is @60hz i.e 60fps capped. Again, the screen is upgradable!). Simply, if you can run a game at 1080p at 60fps or higher, then you will have a similar experience of performance for the HDK. The headset is stereoscopic, which means that you’re experiencing true 3D through the headset, and is not a side-by-side screen mirroring like low quality virtual reality headsets (though you have an option to turn that on if you wish via the control panel). Currently OSVR is natively supported in Unreal Engine 4.12, and CryEngine, with Unity3D support catered for via asset store package plug-ins, and other community based home-brew methods.

One might be lead to believe that one of the drawbacks or limitations of the OSVR HDK is obviously the 1080p screen, since the pixel-screen effects (seeing individual pixels and their borders) is quite a bit more noticeable than with the Rift and Vive (though keep in mind that those devices are not immune from this effect either) at this resolution. It should be noted however, that Razer intends to keep the price-barrier of entry low for developers with low-end to mid-range PCs so that they can begin to develop and experience VR at a low price point. The 1080p screen is a concious decision to keep the price of the base unit low, for this reason, and the display is replaceable should you choose to swap it out for another in the future. The newest iteration of the HDK is the 1.4 version via the store, which adds a filter to the screen that mitigates the pixel-screen effect as much as possible, but I am currently using the 1.3 version until the screen filter upgrade comes as an individual purchase on the store (due sometime in April). The only real drawback besides the lack of current supported titles that are polished/engaging products (a problem all VR platforms have currently), is the runtime setup. After installing the drivers for the headset, you’re required to run what’s called the OSVR Server Runtime Environment, which is what makes your headset detectable to software while it runs. Whilst this is running, you can open SteamVR from your Steam Library, and games that work via SteamVR that require no motion controller input, should work with the OSVR HDK via this method. Before this however, you need to add a SteamVR plugin .dll file to your Steam folder on your hard drive, so that SteamVR recognises the HDK as a supported device, and you’re required to change a .txt file within the Steam folder to add the -OSVR tag into the device list, in order for SteamVR to search for that device. You also need to be running the OSVR HDK as an extended monitor for all of this to work, mirroring displays to the headset display is not a viable method for SteamVR, as it uses its compositor software to output games launched through SteamVR out to an extended/individual display i.e your Vive/other headset. For the not so technically-minded amongst us, the extra steps required could be a bit of a headache. This will all likely be streamlined in the future as developers of the OSVR platform all contribute to simplify the process, and as other software begins to support the OSVR framework natively.

If you can handle a little bit of DIY tasks in the software setup however, and don’t mind doing a little bit of research on how to get different apps and games working via OSVR, then the pros of opting for the HDK instead of the Rift or Vive can massively outweigh the very few cons. For instance, the headset is only $299 (it worked out around £220 for me), and is probably the cheapest option you’ll have for a 1080p display headset, with IR rotational and positional tracking via camera (for the same price, you can now order a 1.4 version with a few improvements). The fact that each piece is removable and upgradable is a huge plus, as you’ll only have to spend, say for example, £120 on a new 1440p screen instead of buying a new £500 headset outright. The 1.3 version I have was quite uncomfortable after prolonged use, because there was no foam or soft material covering my nose, and the hard metal casing of the optics dug into my nose after 15 or so minutes of a headset weighing down on it, but the 1.4 version has a nose bridge included, so at least the improvements are ongoing and promising (the nose bridge will be purchasable for me as a separate and cheap add-on this month too I’ve heard!). The screen brightness is quite nice too; I’ve tried virtual reality solutions before where the screen is too dim, and doesn’t pull you in enough as a result. I’d imagine with the filter for the screen to reduce the pixel-screen effects the display currently has, and a more comfortable nose bridge, the 1.4 version on sale now is the best version for people to enter the Virtual Reality space with, at a low price, and with only a little bit of tweaking required as new developers and publishers are signing up to natively support the OSVR framework every day.





So in conclusion, is the OSVR HDK a capable and wise alternative to the Rift or the Vive? Like most questions of this nature; it depends. For a developer on a budget, who wants to create virtual reality experiences, but lacks the funding to purchase an expensive headset, then I would instantly recommend this as your development unit. It serves its purpose nicely, and is a nice way to make sure that you’re developing your application for the OSVR framework, which means a wide range of users with different displays will be able to enjoy your experience, no matter which headset they opt for. For gamers or consumers, I would say to be careful in making this decision, as the experience very much depends on how much effort you’re prepared to invest to make things work. I wouldn’t call it difficult; if you can troubleshoot most PC problems yourself via Google, then you already have the qualifications needed to get the HDK to work with a few pieces of software and games. As time goes on you’ll enjoy the benefit of developers/publishers jumping aboard the OSVR bandwagon and offering native plug-and-play support with more titles. In the meantime however, if you want a simple experience that just works, Oculus Rift is otherwise the cheapest option that has the most widespread support from virtual reality videos, games, and software. That said, the open-source approach will become more widespread as time goes on, and there will be industry standards being developed which will unify the whole experience between various headsets and hardware, and it won’t matter which headset you choose to buy.

If you want to dip your toe into virtual reality, and you don’t mind a little work to reach this nirvana, then go ahead and spend a relatively small amount of money in comparison to the competition, and enjoy a similar and only slightly lesser experience. With other companies such as Acer pledging their support recently, the stability, native integration, and user-friendly nature of the platform will only get to see better days.