Oculus VR » General http://www.oculusvr.com Oculus VR, a technology company revolutionizing the way people experience video games. Sat, 07 Dec 2013 00:46:47 +0000 en-US hourly 1 http://wordpress.org/?v=3.6.1 Virtual Reality’s Bright Future http://www.oculusvr.com/blog/virtual-realitys-bright-future/ http://www.oculusvr.com/blog/virtual-realitys-bright-future/#comments Fri, 25 Oct 2013 19:20:22 +0000 Oculus VR http://www.oculusvr.com/?p=4532 With so much happening across the industry, we wanted to take a moment and share some of the exciting VR-related news from the last few weeks!

## Gaming Insiders Summit and NVIDIA Tech Event

Last week, the team attended the Gaming Insiders Summit, where Brendan gave a talk about the future of virtual reality, and the NVIDIA event in Montreal, where John Carmack participated in the announcement of their new G-Sync project (we’re very excited to see people getting serious about improving display performance in PC gaming).

John with Jen-Hsun Huang (NVIDIA), Tim Sweeney (Epic Games), and Johan Andersson (EA DICE).
Image courtesy of Engadget.

One of the key topics we discussed was the latest progress around reducing simulator sickness (akin to motion sickness).

We’ve said before that delivering the most comfortable VR experience is a key focus here at Oculus, and tech advancements are bringing us closer to the Holodeck. Luckily for us, Brendan has always been very sensitive to visual errors, which makes him an ideal subject for testing the latest demos. At Gaming Insiders, Brendan talked about using a new VR prototype at Valve, which combines ultra low latency, precise head and positional tracking with low-persistence visuals for one of the most immersive and comfortable experiences ever. We can't share all the details yet, but we're taking the insights we've learned from that demo and applying them to the development process to make the consumer Rift even better.

We’ve also talked about the potential for mobile VR, especially for experiences like VR Cinema and games with creative visuals that don’t require a high-end graphics card. John summed up our vision extremely well during his Engadget interview:

"The way I believe it's going to play out is you will eventually have a head-mounted display that probably runs Android, as a standalone system, that has a system-on-a-chip that's basically like what you have in mobile phones…

A standalone VR headset is the future of VR, especially as mobile computing continues to rapidly advance. Bringing VR to an open platform like Android will pave the way for completely new experiences. The Oculus Android SDK is up and running internally, and we’re working on core optimizations for mobile chipsets now.  Stay tuned for more news on this front!

## Next-Gen Rift Dev Hardware

In John's interview with Engadget (which you can watch below), he mentions a second Rift development kit.

Video courtesy of Engadget.

To clarify: we’d like to ship a new development kit before the consumer version that provides near identical features that developers can build on and test against for the Rift’s launch. That said, we have no plans to announce a new development kit this year. The timing of a new dev kit is tied to the launch of the consumer Rift, and we’ll keep the community posted.

Also, we're working to ensure that content built using the current Rift development kit is compatible with new Oculus hardware, though there will be some integration required to take advantage of the new features, especially for the best experience.

## Marshall Cline Joins Oculus!

We’re excited to introduce Marshall Cline, our new VP of Platform. Marshall is a world renowned software architect, engineer, PhD., and author of the legendary C++ FAQ. His work was an early inspiration for Brendan and Michael when they started in the games industry. Marshall is heading up development of the Oculus platform, which means he’s responsible for all the web services powering your virtual reality experience. Please join us in welcoming him to the team!

## Rift in the News

In case you missed it, the Rift was featured on the Today Show, where Matt Lauer tried the Unreal Engine 4 Elemental demo on the 1080p HD Prototype live on national television!

Images courtesy of TODAY.

The Rift also won a Popular Mechanics Breakthrough Award and a Golden Joystick Award for Innovation of the Year! It’s a huge honor — Thank you for making these possible!

Image courtesy of Popular Mechanics.

Finally, if you’re in the Boston area the weekend of Nov. 2nd, join us for a VR developer meetup! A few of us will be there talking about the Rift, virtual reality, and hardware development. You can find all the details here.

We hope to see you there!

– Palmer and the Oculus team

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Latency Tester Pre-Orders Now Open! http://www.oculusvr.com/blog/latency-tester-pre-orders-now-open/ http://www.oculusvr.com/blog/latency-tester-pre-orders-now-open/#comments Wed, 25 Sep 2013 13:59:07 +0000 Oculus VR http://www.oculusvr.com/?p=4424 Minimizing latency is the first step toward great virtual reality. In March, we announced the Oculus Latency Tester, a tool we developed to help content creators build better virtual reality games by enabling them to quickly and precisely measure motion-to-photons latency from any point in their game pipeline.

We’re pleased to announce that the Latency Tester is finally complete and we’re opening pre-orders starting today at www.oculusvr.com/order/latency-tester/! If you have Oculus Store Credit from the Kickstarter campaign rewards, you can apply it to your pre-order.

Measuring latency of your game is crucial to developing the best possible virtual reality experiences. With the latency tester, we’ve been able to reduce the latency of all Oculus demos and integrations, identify potential rendering improvements more quickly, and uncover secretly buffered frames in different engines and GPUs. It can also be used to test your development setup for optimal latency testings to minimize latency (e.g. graphics card settings, Aero disabled on Windows, etc).

We’re really happy with the final product, and we’ve used it internally to benchmark and optimize latency across all platforms. If you want to learn more about how the guts of the Latency Tester work, you can read the original announcement post here: http://www.oculusvr.com/blog/more-tools-for-great-vr/.

If you reserved your spot in line for a latency tester, please use the same email address at checkout to claim that reservation! Those reservations will place you at the front of the order queue. You must claim your reservation by Sept 30th at 11:59pm PT or your reservation will be forfeited and your spot will be handed to the next person in line.

We manufactured a limited quantity to start, and we’ll make more based on demand. If you have questions about the Latency Tester, head over to the Oculus Developer Forums and let us know. We hope you love it as much as we do!

## GDCE, Gamescom, UNITE, & PAX

We spent the second half of August catching up with developers and gamers around the world at GDC Europe, Gamescom, UNITE, PAX Dev, and PAX Prime.

Palmer and Nate spoke at GDC Europe about why VR will drive content innovation and some of the key challenges facing VR game developers today. If you’re interested to learn more, Gamasutra provided a thorough recap of the challenges portion here.

On the show floors, people lined up for hours to try the latest demos from the community in the HD prototypes. Based on our back of the envelope estimates, we demoed Hawken, Unreal Engine 4, Blue Marble, Undercurrent, iRacing, Proton Pulse, Super Mega Mega, Lunar Flight, First Law, and AaAaa! to over 30,000 people.

The front of the line to try iRacing in the Rift at Gamescom.

The Gamescom booth team getting the word out about virtual reality and the Oculus Rift.

Flying a high-powered mech through the city streets of Hawken…

A special thank you to everyone that waited hours to see the latest demos — We appreciate it!

## Expanding the Oculus Team

We’re looking for more super-talented engineers to help build the best VR platform in the world. In particular, we’re looking for the best and the brighest in the following areas:

If you think you’ve got what it takes to build the Metaverse, let us know! You can apply to any of the above positions, plus many, many more, at careers.oculusvr.com.

## IndieCade and VR Jam 2013

We’ll be at IndieCade next weekend (Oct. 3rd – 6th) talking to developers, showcasing the VR Jam 2013 winners, and hanging out with the community in our back yard. Congratulations again to all the VR Jam finalists and winners!

We’re giving two talks at the IndieCade festival this year:

- Laird is giving a talk on team building and leadership in the video game industry Thursday at 9am PT.

- Palmer and Nate are presenting on virtual reality game design Saturday at 4:30pm PT.

If you’re in the Los Angeles area, stop by the festival and say Hello!

As always, you can keep up on the latest Oculus news on www.oculusvr.com, www.facebook.com/oculusvr, or by following @oculus on Twitter.

Thanks,

– Palmer and the Oculus team

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VR Jam 2013 Winners Announced! http://www.oculusvr.com/blog/vr-jam-2013-winners-announced/ http://www.oculusvr.com/blog/vr-jam-2013-winners-announced/#comments Thu, 19 Sep 2013 15:25:11 +0000 Oculus VR http://www.oculusvr.com/?p=4392 VR Jam 2013 Winners Announced!

Hundreds of developers devoted themselves to building new and original virtual reality games and experiences for VR Jam 2013 with over $50,000 in prizes on the line. We challenged teams to experiment with VR game design, and it was incredible to see the response and innovation from the community: over 220 teams comprised of nearly 1,000 individuals submitted made-for-VR games! That’s a remarkable amount of new VR games and experiences in just 3 weeks. Submissions were graded based on audio/visual design, game design, virtual reality design, innovation, story/world design, and overall fun by a panel of over 30 judges. The verdicts are in, and we’re pleased to share the winners of VR Jam 2013 as selected by IndieCade, Oculus, and a few friends in the industry: Scoring for the finalists was incredibly close, and we’d like to congratulate Ciess and Virtual Internet Hacker on taking home the grand prizes! The Ciess and Virtual Internet Hacker teams will each receive$10,000, a trip to attend and exhibit their game at IndieCade 2013, and an invitation to visit Oculus HQ and spend the day with the Oculus team.

If you haven’t had a chance to play the winning games (or finalists) yet, carve out some time soon! The jam is packed with great, made-for-VR games to play and learn from. You can check out the VR Jam 2013 site for more information on the winning teams and the VR Jam Official Forum for more games from the jam.

We’d like to congratulate each of the winners, as well as every developer who created an experience for the jam. Playing through all the entries has been an inspiring glimpse of what’s to come and we’re looking forward to seeing where these projects go next!

The Oculus and IndieCade teams will both be at IndieCade in Culver City, CA October 3rd – 6th. If you’re in the area, swing by, say Hello, and check out some new VR games with us!

Thank you again, and we’ll see you next year!

– Oculus & IndieCade

www.oculusvr.com/vrjam

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VR Jam 2013 Finalists Announced http://www.oculusvr.com/blog/vr-jam-2013-finalists-announced/ http://www.oculusvr.com/blog/vr-jam-2013-finalists-announced/#comments Fri, 13 Sep 2013 15:03:47 +0000 Oculus VR http://www.oculusvr.com/?p=4362 VR Jam 2013 Finalists Announced!

The development stage of VR Jam is complete and we’re pleased to share the 20 finalists as selected by IndieCade, Oculus, and few friends in the games industry. Hundreds of developers devoted themselves to building new and original virtual reality experiences, with over $50,000 in prizes on the line. We challenged developers to experiment with VR game design and it was incredible to see the response and innovation from the community: over 220 teams comprised of nearly 1,000 individuals submitted made-for-VR games! That’s a remarkable amount of new VR content for just 3 weeks. Submissions were graded based on audio/visual design, game design, virtual reality design, innovation, story/world design, and overall fun by a panel of over 30 judges. After playing every last game and experience, we’re thrilled to present the 20 finalists for VR Jam 2013: More details on the finalists can be found at the VR Jam Portal. If you're interested in seeing more of the jam submissions, check out the VR Jam Official Forum. From this pool of finalists, we will select 1st, 2nd, and 3rd placements. Those winners will be announced Thursday, Sept 19. The top team from each group (Open Call and Selected Developer) will receive$10,000 in cash, the opportunity to exhibit at IndieCade 2013, and a trip to Oculus HQ to meet the Oculus team.

We’d like to congratulate each of the finalists, as well as every developer who created a VR experience for the jam. Playing through all the entries has been an inspiring glimpse of what’s to come.

Thank you again and we’ll see you next week!

– Oculus & IndieCade
@oculus | @indiecade
www.oculusvr.com/vrjam

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Announcing Oculus Share (Beta)! http://www.oculusvr.com/blog/announcing-oculus-share-beta/ http://www.oculusvr.com/blog/announcing-oculus-share-beta/#comments Mon, 19 Aug 2013 14:44:08 +0000 Oculus VR http://www.oculusvr.com/?p=4306 We’re constantly looking at ways to improve the Oculus developer experience. One area we’ve focused on behind-the-scenes is the sharing and publishing of Oculus-ready games and experiences.

Today we’re excited to announce the beta launch of Oculus Share, a new platform that lets you self-publish, discover, download, and play the best VR games and experiences out there.

Oculus Share (or simply, Share) is the first of many steps we’re taking to build the best virtual reality platform. With Share, you can host Oculus-ready games and experiences that you’ve created, browse and download content from other developers, rate experiences on quality and VR comfort level, provide feedback to devs on what you enjoyed (and what you didn’t), and tip fellow developers for their work in cash, should you feel so inclined.

Oculus Share is available now at share.oculusvr.com. You can log in with the same Oculus username and password you use for the Developer Center.

Experimentation, iteration, and actual playtesting are at the heart of pushing virtual reality forward. One of the main goals in building Share was to help developers on all these fronts by creating a centralized community portal for Oculus content. And while it’s simply a sharing service today, over the coming months we’ll work toward making Share an incredible marketplace for Oculus-ready games, experiences, and applications.

Initially, we’ll be vetting submissions to make sure the content isn’t offensive or malicious. If you’re planning to submit your work right away, please be patient as we improve and streamline the approval process.

We’d like to give a special thank you to the developers who helped us alpha test Share, including Cloudhead Games, Owlchemy Labs, UXGround, Justin Moravetz, Aldin Dynamics, Lumina Celare, TerraNovita Software BVBA, and Enno Gottschalk.

Share is designed to be community-driven. If you have questions, comments, or suggestions on how we can improve, let us know at support@oculusvr.com.

We hope Share helps you build the best VR games you possibly can. This is just the beginning!

Participants will be challenged to build new, innovative virtual reality games and experiences designed specifically for the Oculus Rift. The team that develops the best new VR game will win a $10,000 cash prize, a trip to demo its game at IndieCade Festival 2013 to showcase its work, and an invitation to visit Oculus HQ to meet the Oculus team. If you’re interested, you can head over to http://www.oculusvr.com/vrjam for all the details and sign-up. VR Jam begins August 2nd, 2013 at 9:00am PT, but you can sign up your team starting today! # Prizes In case you're curious about the actual prizes we'll be awarding to the winners, we've included the details below. Grand prize winners will receive: •$10,000 cash prize.
• Oculus will pay for travel and lodging for 1 member of the winning team to attend IndieCade and exhibit at event (up to $2,000). • An invitation to visit Oculus HQ to meet the Oculus team. • Oculus will promote the content through social channels. • Opportunity to exhibit winning content at IndieCade 2013. • Coupon for submission to IndieCade 2014. • A limited edition Oculus + IndieCade VR Jam 2013 t-shirt. 2nd place winners will receive: •$5,000 cash prize.
• Oculus will promote the content through social channels.
• Opportunity to exhibit winning content at IndieCade 2013.
• Coupon for submission to IndieCade 2014.
• A limited edition Oculus + IndieCade VR Jam 2013 t-shirt.

3rd place winners will receive:

• $3,000 cash prize. • Oculus will promote the content through social channels. • Opportunity to exhibit winning content at IndieCade 2013. • Coupon for submission to IndieCade 2014. • A limited edition Oculus + IndieCade VR Jam 2013 t-shirt. Each finalist will receive: •$500 cash prize.
• Oculus will promote the content through social channels.
• Coupon for submission (any game) to IndieCade 2014.
• A limited edition Oculus + IndieCade VR Jam 2013 t-shirt.

We'll be handling the judging in tandem with the IndieCade team, so we're looking forward to seeing what you come up with!

If you have any questions in the meantime, don't hesitate to email us at jam@indiecade.com.

We’ll see you in the game (jam)!

–Palmer and the Oculus team

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New Tech Blogs http://www.oculusvr.com/blog/new-tech-blogs/ http://www.oculusvr.com/blog/new-tech-blogs/#comments Fri, 12 Jul 2013 16:17:51 +0000 Oculus VR http://www.oculusvr.com/?p=4006

# New Tech Blogs

We have two new research posts to share with the community.

The first is a follow-up from our resident scientist, Steve LaValle, in which he dives into the details behind modern predictive tracking.

Steve LaValle: The Latent Power of Prediction

“In VR, latency is widely recognized as a key source of disorientation and disbelief (the brain cannot be fooled). In this post, I will argue that simple prediction techniques can reduce latency so much that it is no longer the main problem. Simply present the image that corresponds to where the head is going to be, rather than where it was.”

Tom Forsyth kicks off his own blog with a post about the potential causes of VR sickness and how developers can begin to tackle it with thoughtful game design. This is the first post in a series about VR sickness and the challenges associated with it.

Tom Forsyth: VR Sickness, The Rift, and How Game Developers Can Help

“Despite extensive research, the precise physical mechanisms are still poorly understood. This is not unique to VR – the causes of most forms of motion-induced illness such as seasickness and spacesickness are also poorly understood. Although we don’t understand the physiology well, we do understand many of the things that cause it. A few of these causes are inherent in the desired experience, but many of them can be solved with good (though complex) engineering.”

We have more posts like these coming from other Oculus developers soon. If you enjoyed reading these, maybe you should be working with us! You can check out the latest job openings at http://www.oculusvr.com/careers.

Here are just a few of the positions we’re hiring for:
Embedded Systems Engineer
Systems and Drivers Engineer
Senior Web Engineer (Web Services)
Senior Android Engineer

Finally, this past week we were selected for Develop’s Technical Innovation Award!

We’re honored to be included in such an amazing list of industry pioneers. Thank you to the entire Oculus community for believing in next-generation virtual reality and making all of this possible.

See you in the game!

– Palmer and the Oculus team

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The Latent Power of Prediction http://www.oculusvr.com/blog/the-latent-power-of-prediction/ http://www.oculusvr.com/blog/the-latent-power-of-prediction/#comments Fri, 12 Jul 2013 16:00:35 +0000 Steve LaValle http://www.oculusvr.com/?p=3509 “You are defeated. Instead of shooting where I was, you should have shot where I was going to be. Muahahahaha!”
-Lrrr (character from Futurama, after invading Earth in Space Invaders style)

Introduction

We have all learned that latency is the bane of virtual reality. Because your head freely rotates, presenting the correct image to your eyes is like firing a bullet at a moving target. The target is “sighted” by sensor fusion software, which provides the direction you are currently looking (see [8] for a survey of techniques). Latency is the time it takes between your head moving to a new orientation and the correct image arriving on your retinas. In real, old-fashioned reality, the latency is effectively zero. In VR, latency is widely recognized as a key source of disorientation and disbelief (the brain cannot be fooled). In this post, I will argue that simple prediction techniques can reduce latency so much that it is no longer the main problem. Simply present the image that corresponds to where the head is going to be, rather than where it was.

As enthusiasm for VR gaming has ramped up over the past year, recent blog articles and talks by veterans John Carmack and Michael Abrash have focused on latency as the key obstacle. In [3], Carmack provides a nice summary of the factors that contribute to latency. He offers some strategies to reduce it, but does not emphasize prediction as serious contender. In [1], Abrash calls for fundamental change in the way rendering and display technology are currently pursued so that latency can be reduced while maintaining high fidelity images. I hope this happens because it could improve VR experiences on all fronts! Prediction, however, is discouraged due to increased error when the motion direction changes.

How much latency is too much? Based on VR research during the 1990s, 60 milliseconds (ms) has been commonly cited as an upper limit for acceptable VR. Even so, I definitely notice a disturbing lag when the latency is greater than 40ms. Most people agree that if latency is below 20ms, then the lag is no longer perceptible. Abrash even calls for 7ms to 15ms to be safe. How close are we in modern times? For a game running at 60 FPS, the latency when using the Oculus Rift Development Kit is typically in the range from 30ms to 50ms, including time for sensing, data arrival over USB, sensor fusion, game simulation, rendering, and video output. Other factors, such as LCD pixel switching times, game complexity, and unintentional frame buffering may drive it higher, but it is important to note that the latency period is generally shorter than it was decades ago.

Why is prediction often not taken too seriously? The most likely reason is that through decades of VR research, it has become widely known as a double-edged sword. Most of the time it works, but then makes catastrophic errors when the head motion abruptly changes. This was true across a wide range of VR and AR systems; however, the game has changed thanks to new technologies. The main factors are:

1. How far into the future do we need to predict?
2. How far into the past do we need to look to estimate the trajectory?

Regarding the first factor, Ronald Azuma’s highly cited 1995 thesis [2] on predictive tracking for AR insists on keeping the prediction interval “short”: Below 80ms! If the latency in a current system is only 50ms, then accurately predicting around 30 to 40ms into the future would already tackle most of the problem, even satisfying Abrash’s extreme demands.

To understand the effect of shortening the prediction interval, suppose that the head accelerates at a rate of $\alpha$ deg/sec². After $t$ seconds, the angular velocity will change by $\alpha t$ deg/sec and the orientation will change by $\frac{1}{2} \alpha t^2$ degrees. It is notoriously difficult to estimate time derivatives, making it hard to accurately measure angular acceleration [5]. Furthermore, the acceleration could change during the prediction interval. In either case, the error could grow at least quadratically with respect to the prediction interval length. For an aggressive acceleration of 1000 deg/sec² that goes unaccounted for (see the figure), the error in head orientation for 20ms is 0.2 degrees. For 40ms, it is already 0.8 degrees. At 80ms, it is already up to 3.2 degrees. Therefore, predicting 20ms into the future is much easier than predicting 40ms, and 40ms is much easier than 60 to 80ms. Also working to our advantage in shorter intervals is the fact that the head, while wearing a VR headset, has significant momentum. This has a smoothing effect that prohibits excessive rate changes.

Now consider the second factor: If we need to look too far into the past to reliably estimate the trend, then an implicit latency is built into the estimate. Suppose that optical tracking is performed using cameras at a nice rate of 60 frames per second. This means an estimate of the head orientation arrives every 16.67ms. If these estimates are noisy, and we would furthermore like to know how the orientation is changing, then several measurements are needed. If we use 6 samples, then we have reached 100ms into the past to determine the trend, effectively lengthening the prediction interval.

We can thank the smartphone industry for helping with this problem. MEMS-based sensors continue to improve, providing accurate, high-frequency measurements in a tiny, low-cost package. Modern gyroscopes provide angular velocity measurements at 1000Hz. Even at this incredible rate, the measurements are even prefiltered to reduce noise; raw measurements can be obtained at around 10,000Hz. So, only 1ms of MEMS gyroscope data may be more informative than looking 100ms into the past with an optical tracking system. Better yet, a few milliseconds of gyroscope data could enable accelerations or higher-order trends to be estimated.

To summarize, the game has changed: Trackers do not need to predict as far into the future, and they barely need to look into the past.

Some Technical Details

Predictive tracking or filtering is an old idea, extending back to the early days of signal processing and control theory. Let the state refer to the quantity that we would like to track and predict. A classical example is the position, orientation, and velocity of an aircraft. Predictive filtering is based on three parts:

1. The sensor readings up until now.
2. A model of what each reading tells about the state at that time.
3. A model of how the state changes over time.

To keep it simple, let’s suppose that #1 and #2 cause no trouble: A sensor reading directly provides the current state. If we obtain sensor readings at regular intervals (for example, every 10 ms), then what will the state be one step into the future? Let $x[i]$ refer to the ith reading. A linear prediction approach looks like

$x[k] := a_1 x[k-1] + a_2 x[k-2] + a_3 x[k-3] + \cdots + a_n x[k-n]$,

in which $a_1, \ldots, a_n$ are constants chosen in advance. They provide the predictive model (#3 above). For example, $x[k] := x[k-1]$ is a simple model which predicts that the state will never change. The model $x[k] := 2 x[k-1]-x[k-2]$ predicts that the state changes at a fixed rate. More complicated linear prediction filters can handle other factors, such as noise reduction and state acceleration.

Linear prediction is just one type of filter among many others. For example, Bayesian filters use probabilistic modeling (in #2 and #3 above) to arrive at distributions over possible current states and future states. Heavier weights are given to more likely futures. The celebrated Kalman filter is a famous special case of Bayesian filters for which all of the distributions become Gaussian and there is a nice update formula for each step. The most basic and general way to view filter design is in terms of information states, an idea introduced by von Neumann and Morgenstern [7]: When playing an iterative game with uncertain current state, all past information is compressed into some representation that is critical for decision making. In our case, the “decision” is specifying the future state. The information state is updated in each stage, and forms the basis for a decision. Think about what you need to keep track of to play Battleship effectively. Card counting strategies for Blackjack are another good example. Finally, what information state should a game AI maintain? For filtering from an information-state perspective, see Chapter 11 of my book.

Now consider tracking head orientation, which means the state is a quaternion that represents head orientation. From my previous blog post, the orientation is updated every millisecond by calculating a quaternion that represents the rotation that occurred over that time interval. The critical piece of information is the current angular velocity, as measured using a gyroscope.

Consider the following methods:

1. No prediction: Just present the updated quaternion to the renderer.
2. Constant rate: Assume the currently measured angular velocity will remain constant over the latency interval.
3. Constant acceleration: Estimate angular acceleration and adjust angular velocity accordingly over the latency interval.

The first method seems absurd because it assumes that the head will immediately come to a complete stop and remain that way over the latency interval (recall $x[k] := x[k-1]$). The second method extends the rotation rate over the latency interval (recall $x[k] := 2x[k-1]-x[k-2]$, but now we use the angular velocity). If the rotation rate remains constant, then the rotation axis is unchanged. We only need to extend the rotation angle about that axis to account for the longer time interval. To predict 20ms into the future, simply replace $\Delta t= 0.001$ with $\Delta t = 0.021$. The third method allows the angular velocity to change at a linear rate when looking into the future. The angular acceleration is estimated from the change in gyroscope data. For each small step 1ms into the future, the acceleration is applied to change the predicted angular velocity. For example, if the head is decelerating, then its predicted angular velocity will be smaller in each time step along the latency interval. The figure shows their differences in terms of calculated angular velocity over the prediction interval.

One remaining detail is noise reduction. Errors in estimating the current angular velocity tend to be amplified when making predictions over a long time interval. Vibrations derived from noise are particularly noticeable when the head is not rotating quickly. Therefore, we use simple smoothing filters in the estimation of current angular velocity (Methods 2 and 3) and current angular acceleration (Method 3). We use Savitzky-Golay filters, but many other methods should work just as well.

Performance

A simple way to evaluate performance is to record predicted values and compare them to the current estimated value after the prediction interval has passed. Note that this does not compare to actual ground truth, but it is very close because the drift error rate from gyroscope integration is very small over the prediction interval. I’ve compared the performance of several methods with prediction intervals ranging from 20ms to 100ms. The following graph shows error in terms of degrees, for a prediction interval of 20ms, using the Oculus Rift sensor over a 3 second interval:

I was wearing the Rift and turning my head back and forth, with a peak rate of about 240 deg/sec, which is fairly fast. This is close to reported peak velocities in published VR studies [4,6]. The blue line represents Method 1 (no prediction), which performs the worst. The red line shows Method 2 (constant rate), which is much improved. The yellow line shows Method 3 (constant acceleration), which performs the best in the comparison. Method 1 is used by default in the original SDK release for the Rift Development Kit, but with prediction turned on, Method 2 is used. A variant of Method 3 is expected to appear in an upcoming release.

Numerically, the angular errors for predicting 20ms into the future are:

 Method Average error Worst error 1 1.46302 4.77900 2 0.19395 0.71637 3 0.07596 0.35879

During these motions, the acceleration peaked at around 850 deg/sec². The fastest I could rotate my head while wearing the Rift was about 600 deg/sec, with peak accelerations of around 20,000 degrees/sec² (and my neck still hurts as I am typing this). By flipping the Rift in my hands and catching it again, I was able to obtain 1400 deg/sec and 115,000 deg/sec²; however, these speeds are unreasonable! Typical, slower motions, which are common in game play, yield around 60 deg/sec in velocity and 500 deg/sec² in peak accelerations. For both slow and fast motions with a 20ms prediction interval, Method 3 is generally superior over the others. If we double the prediction interval, then performance degrades; however, the prediction methods remain preferable over nothing. For similar head motions as above, the results for 40ms prediction are:

 Method Average error Worst error 1 3.36267 9.68985 2 0.57410 1.59862 3 0.17338 0.50788

Discussion

During ordinary game play, even with some fast head motions, simple prediction techniques accurately predict 20 to 40ms into the future. Subtracting this time from the actual latency results in an effective latency that is well below 20ms. Hooray! It appears that the holy grail has been reached. But not really. As mentioned before, other factors may drive the actual latency higher. Also, the effect of small prediction errors is difficult to assess. This ties directly into perception, which is an important topic missing from the discussion so far. For example, when the head is almost stationary, small perturbations are more noticeable than when the head quickly rotates. How much error is imperceptible and how does this vary with respect to angular velocity, acceleration, screen resolution, shading methods, and so on? How important is the direction of the error as it propagates over time? Answers to these questions would help to further improve prediction methods. At the same time, improvements in computation power, software, rendering, and display technologies (OLEDs) are expected to reduce the actual latency, which would further shorten the required prediction interval.

Latency is no longer the powerful beast that it once was. It has been beaten down and nearly defeated by modern sensing technology and effective filtering techniques. This will cause attention to shift to a host of other problems. If latency is no longer causing simulator sickness, then what about the game content? A fast ride on a virtual roller coaster may cause more disorientation than latency or other VR system artifacts. Furthermore, what kind of user interfaces are most appropriate? What game genres will emerge to provide the best VR experience? As display resolution and switching speeds improve, how should judder be addressed? The list goes on and on. Exciting times lie ahead!

Acknowledgments

I am grateful to Tom Forsyth, Peter Giokaris, Nate Mitchell, and Laurent Scallie for helpful discussions.

References

[1] Abrash, Michael, Latency: The Sine Qua Non of AR and VR, blog post, Dec. 29, 2012.

[2] Azuma, Ronald, Predictive Tracking for Augmented Reality, PhD Thesis, Uniersity of North Carolina, 1995.

[3] Carmack, John, Latency Mitigation Strategies, blog post, Feb. 22, 2013.

[4] List, Uwe H. Nonlinear Prediction of Head Movements for Helmet-Mounted Displays. Technical report AFHRLTP-83-45, William AFB, AZ: Operations Training Division Air Force Human Resources Laboratory, 1983.

[5] Ovaska, S. J., and Valiviita, S., Angular Acceleration Measurement: A Review, IEEE Transactions on Instrumentation and Measurement, Volume 47, Number 5, Pages 1211-1217, 1998.

[6] Smith Jr., Bernard R., Digital Head Tracking and Position: Prediction for Helmet Mounted Visual Display Systems, Proceedings of AIAA 22nd Aerospace Sciences Meeting, 1984.

[7] von Neumann, John, and Morgenstern, Oskar, Theory of Games and Economic Behavior, Princeton University Press, 1944.

[8] Welch, Greg, and Foxlin, Eric, Motion Tracking: No Silver Bullet, but a Respectable Arsenal, Computer Graphics and Applications, Volume 22, Number 6, Pages 24-38, 2002.

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Shipping Update, E3 2013 Recap and Oculus 0.2.3 SDK Release http://www.oculusvr.com/blog/shipping-update-e3-2013-recap-and-oculus-0-2-3-sdk-release/ http://www.oculusvr.com/blog/shipping-update-e3-2013-recap-and-oculus-0-2-3-sdk-release/#comments Thu, 04 Jul 2013 05:19:52 +0000 Oculus VR http://www.oculusvr.com/?p=3850

# Shipping Update

We’re back on track! All of the development kits that were held in US customs are now on their way to developers. We expedited some of the long-distance deliveries to try and get as many Rifts in developers’ hands for the 4th of July weekend. Have fun!

We’ve started shipping post-Kickstarter kits to Australia and New Zealand. With the distribution center coming online, we should have the entire region completely fulfilled in July. Sorry for the delay!

We also recently shipped another 1,000 dev kits throughout Europe, and we’ll have another 1,000 on their way to doorsteps soon. If your order status is “Processing”, you should receive an email notification just after the long weekend.

Thanks for bearing with us as we worked through all these issues. All in all, there are now over 17,000 Rifts out in the wild, and we’ll have shipped all dev kit pre-orders from 2012 by the end of the week!

# E3 2013 Recap

E3 2013 was the first time we showed an HD VR (1080p) Rift prototype to the world. Even more exciting, it was the first E3 where Oculus developers were showcasing their own games and experiences on the show floor! Now that most of the coverage and awards are out, here’s a quick recap of highlights from the show.

“The next generation of gaming hardware was indeed present at E3 this year, but it wasn’t a console manufacturer that delivered it. Instead, it was Oculus VR.” – PC Gamer

“…I spent a few minutes walking around Epic’s Unreal 4 Elemental demo. It is just an example of the tech, but it felt more next-gen than most of the things Microsoft and Sony showed the world at their press events Monday.” – VentureBeat

Game Critics Awards – Best Hardware

The Game Critics Awards are the official awards of E3, decided by 30 of the top publications in the industry. This is an honor, and we’re humbled to have been selected.

A enormous thank you to Epic Games, helped us with the Unreal Engine 4 integration and the amazing Elemental VR demo for the show, all running 60 FPS in stereo 3D on our 1080p prototype hardware. We couldn’t have had such a jaw-dropping demo without their support. A special thank you to Nick W., Nick P., and Alan W. at Epic for truly going above and beyond to deliver the best-possible VR experience.

We’d also like to thank UX Ground again for letting us showcase the VR Cinema 3D demo, built using Unity with the official Oculus integration. Kicking back inside a virtual movie theater in HD VR may just be the future of mobile movie-going.

Finally, we’d like to the thank you. It’s been just over a year since John Carmack showcased the Oculus Rift at E3 2012. Virtual reality has come a long way in one year, and it wouldn’t have been possible without the support of our Kickstarter backers and the amazing community of Rift developers around the world. Thank you again!

These awards really belong to the entire Oculus community — those of you who have shared our vision for the Rift and believed in VR’s potential for next-gen gaming. Congratulations!

Here are a few of the other great awards that the Rift came away with:

IGN – Coolest Tech
IGN Italia – Best Innovation
Machinima – Best Hardware
Game Informer – Best Tech
Flesh Eating Zipper – Best Peripheral
SBTV Games and Gadgets – Pick of E3
POP Brazil – Best Peripheral

# EVE-VR

EVE-VR, the space dogfighting demo built by the team at CCP, captured the hearts of everyone that experienced it, winning over 5 awards. From their small meeting room above the show floor, CCP stole the show and garnered incredible praise and accolades from attendees.

Here are just a couple of the awards that they took home from E3 2013:

IGN – Most Innovative Game
“…It’s a tech demo. But holy &^#\$ what a tech demo it was. Space dogfighting with headtracking and immersion like you’ve never experienced. You look down and you can see your own body. But it’s not your body! WHAAAAAAAAAAAT!”

PC Gamer – Best Game of E3
“…the game made a staggering impression on me that’s become more vivid—not less—since I first tried it as I imagine all the possibilities, all the first experiments and games, coming to PC gamers in the very near future.”

Congratulations to the EVE-VR team on their success! We can’t wait to see what they do next.

# IndieCade

We’d also like to congratulate all of the Rift developers that demoed at the IndieCade booth at E3: SoundSelf, The Recital, If a Tree Screams in the Forest, Irrational Exuberance, and Homework from Another World. It was awesome to see such excitement and exploration around virtual reality at the show. A special congratulations to the Sound Self team for winning Best Indie Game of E3 from Flesh Eating Zipper!

Palmer with Robin from the SoundSelf team celebrating ‘Best Indie Game’ nomination!

# Oculus 0.2.3 SDK Release

We just released Oculus SDK v0.2.3 on the Oculus Developer Center. Highlights of the release include:

• Added Linux support to the Oculus C++ SDK and OculusWorldDemo.
• Added Oculus player profile, used to save/restore player settings including interpupillary distance, height, and lens cups.
• Introduced Oculus Config Utility that allows players to easily configure their Oculus profile. The utility includes an IPD measurement framework.
• Improved magnetometer algorithm to support a full sphere of orientations.

If you’re interested, you can read the full build notes for the release here.

Here’s to many great years of virtual reality at E3!

– Palmer and the Oculus team

P.S. Congratulations to our friends at Respawn Entertainment and the Titanfall team on winning a record 6 Game Critics Awards at E3! We can’t wait to play it.

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