The Feel

Spring 2016, SteamVR + HTC Vive Pre​

Denny, our CEO and creative director, was pushing for more experimentation with our artificial locomotion options. We played with different settings, from uni-directional (forward only), to bi-directional (forward-backward), to strafing enabled (side-to-side). These methods were still causing sickness, but Denny was working toward vection mitigation when he got to the idea of a porthole.

During artificial movement, we would bring a mask around the periphery of the eyes—a portal of sorts that we called a ‘Vection Portal’. With it, you could feel motion as you moved through the level, but without the fast-moving peripheral motion that made it uncomfortable.

Despite these new comfort options for artificial locomotion, nausea wasn’t totally solved, and Blink was still the right feel for the game. Blink married The Gallery’s cinematic style, it was comfortable for mass adoption, and it inspired players to move around within their physical space.

In the end, we had to choose one. We were a small team, and testing large VR levels with multiple locomotion methods wasn’t in the cards. We had to fully integrate and support one method, and we decided to stick with Blink.

From there I was able to optimize the game’s performance entirely around Blink. I could instantly bring in specific items based on the player Blinking into certain zones, and then cull the others. We were able to cut down processing and increase the fidelity of the game because fewer areas needed to be persistent at all times.

When the first episode of The Gallery finished and public adoption of VR finally arrived in April 2016, the take on Blink was increasingly polarized. Teleportation had become the standard, but the rotational and persistent bounds features we added with Blink felt too insular. Valve had made simultaneous developments to their teleportation, and player preference leaned toward those minimalist, built-in systems. We had inadvertently invented many of the same wheels and our systems ultimately overlapped.

When the Oculus Touch controllers released in December 2016, we updated Blink to be more in-line with the standards of the time. Rather than aiming with your head (literally looking to where you wanted to go) as we originally had it, we set the default to cast from the hand, so you could point to your destination instead. We also added a ballistics trajectory arc that felt more intuitive to our players, albeit less connected to our world.

The feeling mattered, but so did the options.

Free Locomotion

Winter 2016, Oculus Rift CV1 + Oculus Touch​

Artificial locomotion was taking on a new name: ‘Free Locomotion’. Onward—a tactical FPS fully-integrated with smooth, artificial locomotion—had become a cult hit with VR gamers. Some players felt that Free Locomotion was now the only way they could feel truly immersed. There was an outcry from the community any time a game lacked the option, and we would ultimately add support in the second episode of The Gallery, despite it being built for our default option, Blink.

Also gaining traction at the time was ArmSwinger. What I immediately liked about the ArmSwinger demo I saw was that the controllers inferred the player’s body direction by the motions they performed. You could turn the body with the direction of the arms, and still allow the head to pan decoupled from that direction. The downside to ArmSwinger however, was that it still used up a button and didn’t ultimately address vection issues.

Valve had let us in on another secret: because of the depth of our hand functionality, The Gallery was used to reveal the first prototype of the SteamVR ‘Knuckles’ controllers at Steam Dev Days 2016. These new controllers were trending away from buttons and the abstraction they produced; hand interactions could be performed by tracking of individual fingers, rather than with binary button inputs. With this in mind, I decided to augment the ArmSwinger mechanic to be buttonless.

I began researching FFTs, or ‘fast Fourier transforms’. I had studied them before for audio, but I was beginning to see their relevance in kinematics. The transforms can extract any number of combined waveforms within a time domain into an ordered table of discrete frequencies and amplitudes. More colloquially, the FFTs let me read body noise from motions of controllers and turn it into practical data.

I could then set the exact threshold of when movement should start; two periods that are cached or buffered can tell me when a player is running in spot based on their arm frequencies. With this method, you could swing one arm and pick an object up with the other while still continuing to move.

With body pucks (such as the Vive Tracker) not yet available to the public, full-body persistence would require us to infer the root position of the player. Once there, however, you could use height and leg data to start tailoring leg strength coefficient and calculating the specific physics and kinematics of any single person. Players could run at the same frequency beside each other, yet still have different travel distances.

In practice, games like Sprint Vector with its peripheral VFX have shown that ArmSwinger-like locomotion can help mitigate vection issues. The physical bobbing while you run is enough to ease into motion but still keep you grounded—there’s no lurching, and there’s limited vestibular disconnect. It’s a great option for free locomotion without sacrificing comfort. Plus, the cardio, you know?

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  • Doctor Bambi

    Thank you guys for sharing your insights, locomotion is such a fascinating problem for VR and all the experimentation going on is super exciting. I feel like every game that implements something new, we get a little bit closer to that “dual analog stick” moment where we find the best compromise that fits within the practical limitations of VR.

  • PJ

    Good read.

    Honestly, I think smooth locomotion should be standard. Valve and oculus should both have smooth locomotion in there ‘homes’, there should a be a ‘training’ center so people can get over the sickness. I suffered horribly when I first played VR, on EVERYTHING, I read a reddit post on how to combat VR sickness, I was desperate to find my ‘vr legs’ because I loved being immersed in VR, it blew me away. So, i took regular breaks, I stopped as soon as felt queasy, and put the Rift back on when I felt up to it, I bought motion sickness tablets too, and took one every time I played a game with smooth loco like BAM or a fast moving game like Dirt Rally, it took me about 3 weeks and then I was playing for hours on end, nothing at makes me ill. I have since passed my expereince to friends and an co workers who have gotten into VR, it’s worked them all.
    I’m a firm believer in EVERYONE CAN GET OVER MOTION ILLNESS, just some quicker than others.
    A friend bought a Vive, a couple of weeks ago, so me and some VR buddies set up a private game on Pavlov (smooth locomotion, fun, and cheap, it’s a good way of getting ‘vr legs’) wasnt long until he was sick at 1st, a week later he was playing for 2 hours straight

    • Raphael

      You demonstrated a strong desire to overcome and that made you seek out solutions rather than doing what most nausea gamers do and complain this or that game makes them sick and then relying on teleport forever more.

      • J.C.

        VR will NOT take off if you have to tell people “it’ll make you feel really awful a lot, but you’ll eventually feel fine”. I’m not saying teleportation is the answer. It’s a placeholder until something feels right, and good, the first time it’s used. It will get figured out, or…VR will stay niche.

        • Raphael

          The “really awful” thing is a minority. The extreme end of the scale. You make it sound like everyone new to vr is going to vomit. That’s just not true. VR being niche is dependent on price and specification…it’s absolutely not governed by the nausea minority.

          • J.C.

            And YOU act like everyone will try VR even after hearing how sick it made someone they know. Most will decide they don’t want to find out IF it will make them sick, there are plenty of other things to do in this world than spend a bunch of money on a barf machine.

            We all love VR on here, yes? The general public doesn’t give a shit about it. A huge percentage of people assume it’s just like 3D movies. VR already has an uphill battle, and if ONE person gets sick, they’ll tell everyone they know to steer clear.

            If VR is to get out of the niche category, it needs to be cheaper, easier to set up (WMR headsets are pretty much there), wireless, have a killer app, and that killer app can’t make people sick. Not one person. The “nausea minority” can very easily keep a massive number of people from ever even trying it out of fear of being ill. Your personal lack of nausea won’t change their minds.

          • Raphael

            And YOU act like everyone violently vomits when they try VR. VR nausea does not affect all new users and those who experience it feel it to varying degrees. You’re a scaremonger and have this paranoid delusion that VR is in great peril unless ALL VR game developers push “comfort” games. In actual fact those comfort games VR was deluged with year one have had a far greater negative impact. I’ve read statements from non-VR users who say VR is crippled by teleport.

            Most VR games now come with multiple movement options so you have nothing to be all panicky and scaremongery about.

            Before VR was affordable there was Fresnel gaming. It was used in some arcades and first emerged in military flight sims. The fresnel combined with monitor display was able to pull the user into that 3d world and could make some people a little dizzy at first. The effect wasn’t lasting and people didn’t get into a state of hyper-anxiety and relay to others how they should avoid it.

            You’re clearly a nausea clan member with your belief that nausea is the primary limiting factor for VR proliferation.

          • Raphael

            You really are pathetic you know? You as head of the nausea clan exaggerate to the point of absurdity. Anyone would think reading your pishy bollocks that VR causes severe vomiting, diarrhea and hospitalisation.

            Anyone who understands VR and who uses it on a regular basis will have the presence of mind to inform new users of the potential issues. And unlike you they won’t scare the shit out of them and tell them they need to exist on a diet of teleport games or die in agony.

          • J.C.

            Looks like your first vitriolic response disappeared, this is your second reply to the same post.

            I don’t get much nausea, despite your clear assumption that I do. If a game takes control of the camera away, THAT can mess me up, but few games do that. I’ve never thrown up from VR, but a couple early, poorly designed experiences DID leave me needing to sit down for a while.

            What I’m trying to convey is that ONE bad experience, with the help of word of mouth, routinely DOES mean several people won’t even TRY something. Ignore it being VR. If someone eats at a new restaurant and they’re the first and only review on Yelp, and it’s negative, that one review absolutely WILL keep a huge number of people from going. We are intristically compelled to warn others if something is bad. I forget what the exact stat is, but it’s something along the lines of “you need 15-20 positive reviews to get people to ignore ONE bad one”. It was a HUGE focus of my company’s management last year. And that bad restaurant review can be bad in multiple ways, but one saying you got sick from going there, or even “I felt sick” is literally the worst thing that could show up in it. And since you like to assume that I only talk about my own experience, no, I don’t work in the food industry.

            I think smooth locomotion is, in the end, the “right” thing for VR. It just needs to not come with a need for acclimation.

            Also, I think snap turning is JUST as experience-ruining as teleporting, but we don’t have huge discussions going about how crappy THAT is.

          • Raphael

            Problem is you have only a partial view of VR that is focused on the idea that anti-nausea is the main criteria for successful VR.

            Why that’s wrong:

            Yes it’s true that nausea is an issue for some people due to the current design of VR hardware. The issue has reduced somewhat since Vive and CV1 which means that those who have mild to moderate sensitivity will experience less to none issues. The smaller part of the spectrum experiencing extreme nausea won’t see any improvement and in some cases these people can’t even handle teleport or any comfort modes (analogy: going to a theme park and taking a ride on a rollercoaster knowing you’re sensitive to motion and then ranting at the ride operator and blaming everyone but yourself).

            You seem to regard VR as being in some kind of deadly peril where everyone needs to experience it with the most huggy comfort aids or else they run screaming in and telling their friends and family to avoid VR. The big flaw with your argument is that most people with who have never tried VR but know of its existence will be curious enough to want to try it for themselves. Consumer VR is such a powerful force now that it does not depend on word of mouth. Of course a percentage will experience nausea and blame VR and spread the word… that word will have ZERO impact on the success of VR because *VR’s growth rate exceeds the percentage who suffer nausea and spread negative opinion.

            (*crucial point: VR’s growth rate is impervious to gossip from a minority who have a bad trip).

            But I see your belief is that the vast majority will suffer nausea when exposed to VR for the first time unless they’re given comfort games… Wrong. Nausea isn’t a universal fact. It affects a percentage to varying degrees. Thus I have a friend who intruduced his mother to Eve Valkyrie (her first ever VR experience). She suffered NO NAUSEA. Same friend exposed his father to VR flightsims… NO NAUSEA. My wife on the other hand can’t even withstand 3 minutes in VR with any experience. I exposed my sisters to VR with space games and DCS World…one sister experienced some dizzyness only at extreme banking of the aircraft.

            I exposed a male friend to DCS world.. His first ever VR experience. He took off and flew the AV8B for 20 minutes with NO NAUSEA. He reported some lightheadedness on banking but he didn’t report any nausea. I realise these stories don’t represent everyone but it’s important to illustrate that not everyone experiences nausea on their first VR experience. The way you talk gives the impression that VR is such a deadly experience that anyone new to it must be fed comfort mode games. This is absolutely false and actually does more damage to VR than the small percentage who had a negative experience and then gossiped.

            So basically your arguments are flawed because you don’t look at any other factors regarding the VR industry. You only have this one idea that new users have bad nausea and then gossip.

            The steam user reviews fully support my statements. A small percentage complain of nausea on VR games more likely to induce it. Each game in question will have only a small percentage of negative reviews citing nausea. You will of course dismiss steam user feedback as false/inaccurate and I dismiss your ideas as false/inaccurate. Steam metric does provide a useful insight for any given game.

    • AndyP

      Good advice. I also found that travel sickness pills helped me overcome any initial motion sickness. Many children get car sick, but overcome it with time.

      • PJ

        Very true, I forgot about that, the 1st FPS did cause many people to feel sick, look how quickly people got over it. VR games devs need to stop pandering to it

    • benz145

      Maybe you can acclimate a bit, but I don’t believe you can completely overcome motion sickness. I get motion sick in cars if I’m trying to read or use my phone, and that’s been the case my entire life. I have no reason to believe it will change.

      • PJ

        Good point, I still use my phone in the car for any real length of time.

        But in VR I’m absolutely fine

      • NooYawker

        I don’t know, initially i used to be pretty woozy and sweaty after a short stint in VR. I’m pretty comfortable in VR these days.

      • Tenka

        The difference between “car sickness” and “VR Sickness” is that its in reverse. Car Sickness, Sea Sickness, Air Sickness occur because there is a physical stimuli provoking a response where the visual is unable to keep up or lagging. VR is the opposite, there is visual stimuli and the physical remains stationary and doesnt keep up.

        Because of this, its far easier to adjust to than traditional motion sickness as its harder to adjust to physical changes in motion than it is to visual. In VR, the physical will always be stationary for everyone .. unless someone else decides to come along and push you over or something. You are never going to be fooled or messed with “physically”, which means you can concentrate 100% on Visual/Audio stimuli to stabilize yourself.

        Pro tip: This means turning off the sound and just closing your eyes pretty much instantly negates VR sickness whenever you want (provided you didnt push yourself beyond the point of no return already).

        I used this techinique to acclimate to VR very quickly .. took me about 2 days completely master Smooth locomotion and falling vertigo when I first started VR back in 2016.

    • NooYawker

      Someone once posted, ,might have been on this site, to bend my knees. The little trick helped me play DoomBFG VR for a few hours where I initially played for maybe 30 minutes.

      • PJ

        Really? I didn’t know about that, great tip.

        These are things that annoys me, sickness can be over come, by doing these simple things, but if it’s not spoken about enough, VR devs need to do more, especially Oculus and Valve, it’s in there best interest to help users over come it or, dare I say, force it upon the user.
        Like i said, a simple ‘training’ room in the ‘homes’ for smooth locomotion will help immensely.

    • Denny Unger

      Forcing smooth locomotion on new users would be tantamount to signing VR’s death-warrant during this critical growth cycle. Where nausea is concerned, a first bad experience in VR is generally the LAST experience those who are sensitive will embark on. And the market can’t sustain that. There are already too many market factors we’re battling against.

      The truth is, we’re still in early days, onboarding a large segment of the population. Teleportation isn’t the end-game but it is the safest onboarding mechanism to ease new users into the medium. Options are important for advanced users but removing teleportation as the default just isn’t an option until there is a better replacement with as much certainty.

      • PJ

        Your post makes sense, but, the sooner users get used to it, the better it is for VR as a whole, then we’ll get big AAA devs porting the big games over, which sorely missing at this point, gamers go were the games are.

        • Joshwa Sanders

          I think smooth location is a lazy band-aid to VR. It’s nice to have, but not very immersive. I’d much prefer a jog-in-place system like COATS Freedom Locomotion.

        • Caven

          The problem is that trying to force acclimation is slower/worse than giving players the option to ease in. I do think all titles should implement smooth locomotion where appropriate, but provide teleportation as a default where possible. That way the player is assured a comfortable initial experience, can switch to smooth locomotion at their leisure, and has teleportation as a fallback if smooth locomotion causes discomfort.

      • Francesco Fazio

        I frankly dont get this “motion sickness” thing. I never had it. I have the Oculus Rift since almost 1.5 years almost and never ever experience something like that. Maybe the only game that made me feel a little but really a little dizzy was Dirt Rally but for all the rest absolutely 0.

        Are the people having motion sickness affected by some kind of body anomalies ?

  • James Butlin

    Very thoughtful and interesting article! Always interesting to see people’s thoughts onon VR locomotion and how far it can be taken. I was 100% on the “I’ll be stuck teleporting or swinging my arms in VR forever” side, but once I’d acclimated to Onward’s smooth locomotion (I was an alpha tester), I found that I could play it absolutely nausea free, and that was a truly freeing realisation. Unfortunately it does require a little getting used to, and it puts off so many people because they turn the game off and refund at the first sign of nausea, when I’m 100% confident they could get past if they tried. It’s a problem I look forward to seeing developers solve.

  • CazCore

    unbelievable, i know, but i solved this problem, for the Quake-like VR game i’m making. :)

    but i want to have an Early Access version of the game up, which is worth paying for, before revealing it to the world. so that hopefully i ensure myself making money for my game at least. and hopefully get credit (at least) for inventing the control scheme. since i don’t know if i’ll be able to successfully capitalize on this FPS-Character-Controller of mine (i’ll sell it on the Unity Asset Store). TONS of games can and probably WILL use my ideas after they experience my game (or read about it). but most will probably recreate it from scratch, rather than paying me anything. or even giving me credit. :)

  • Amazing article. It is very interesting to read all the experiments they have made during these years… and I’m also envious about them having the Knuckles :)

  • Nick Dauchot

    “Current VR owners are desperate for realism and freedom, while the non-owners will never be sold unless they’re comfortable.” love this quote

  • pogo

    Very interesting read! But didn’t you know that a lot of these experiments have already been done by researchers and scientists in the last decades? There’s a lot of literature about this locomotion topic. I always have the feeling that VR devs want to reinvent the wheel…

    • benz145

      The needs of game developers and researchers are vastly different. I’m sure there’s lessons to be learned on both fronts.