Oliver Kreylos

Excellent reality check "Lasers Are Not Magic" http://doc-ok.org/?p=1386 "Can I make a full-field-of-view AR or VR display by directly shining lasers into my eyes?" -- No.

I don't believe the device demo experiences themselves were under NDA, however recording devices had been restricted. Oliver Kreylos did a great writeup a while back on measuring the FOV: http://doc-ok.org/?p=1274

Oliver Kreylos probably has the best description of the current demo: http://doc-ok.org/?p=1223

I'm a bit of a VR enthusiast, and I'm not a gamer, so I think I can answer some of these. >- Outside of car games, space sims, or any other game where the main character is mostly sitting down, does VR work well? Very well. The thing I hate most, as a non-gamer, is having to learn all of the confusing controls. I really like that VR games take away most of the complication and allow you to do what feels natural. Probably for the same reasons a lot of people like the Wii. I've been having a lot of fun in games like Vanishing Realms:a first person dungeon crawling RPG http://store.steampowered.com/app/322770/ , The Unspoken: where you have magic battles in a New York like setting http://www.insomniacgames.com/games/the-unspoken/ , and a bunch of the puzzle type games. >- Apart from games what other applications are there at the moment? Not enough in my opinion, but I've spent the last week using Oculus Medium to make 3D models, and using Quill to make VR paintings. This is actually the area I'm most interested in, and I know that some companies are working behind closed doors at the moment to make more creative tools as well as business and social type tools. -Anyone try replacing their monitor with a VR headset? How'd that go? I do this frequently for consuming movies, but the resolution isn't at a point where I'd recommend it for long periods of time if you're doing text editing. I still occasionally browse and listen to music with the screen set to a gigantic size, but…

Part 1 of an ongoing 4-part write-up. In part four he has released an alpha preview of his open source Oculus and VR framework; see http://github.com/Doc-Ok/OpticalTracking. tl;dr; The Oculus positional tracker system uses 40 IR LEDs, each with a 10-bit cyclic code of bright or dim flashes. The tracker camera is synced to the headset and can identify each LED using these codes, elegantly simplifying the job of recovering the 3D position of the headset (the 'Perspective-n-Point' problem in Computer Vision). This gives very good absolute position and orientation tracking, however degrades when only coplanar LEDs are visible. This can be overcome by fusing the IMU data from the Oculus, which will be the contents of part four when it is written up. This man (Oliver Kreylos) seems to do a great job of explaining computer vision problems. I really enjoyed reading these posts, and others on his blog. He's is very well qualified to write about these topics, as well (see his bio here: http://doc-ok.org/?page_id=6 - he has been researching in this area for years).

Thanks for linking to Doc Ok's youtube channel! https://www.youtube.com/c/okreylos/videos 5 years ago he was active in the Vive VR world http://doc-ok.org/

when your ipd is off its roughly the same thing as being slightly cross-eyed or slightly wall-eyed. if its small enough and the game is low-res enough it can not matter, but if you feel "eye strain" or a sortof between-the-eyes headache after playing for 20 minutes thats where it comes from. its subtle so it really gets you over time, not at any one moment. here's a good howto on measuring your ipd to get it right: http://doc-ok.org/?p=898

Yes it uses both, relative and absolute measurements (each with its own drawbacks) into what's usually called sensor fusion. It's very well explained here: http://doc-ok.org/?p=1478 The headset is not wireless and the controllers have 1-2 ms of latency. They compress the controller data a lot in a very smart way. More info: https://hackaday.com/2016/12/12/cnlohr-reverses-vive-valve-engineers-p…

The open-source Vrui VR toolkit[1] has some level of support for the Vive and Rift[2]. [1] http://idav.ucdavis.edu/~okreylos/ResDev/Vrui/ [2] http://doc-ok.org/?p=1508

UC Davis' CAVE VR environment was used to help find the cities in the LIDAR data: http://doc-ok.org/?p=1204 .

Would they want to compact the optics though? I have absolutely no knowledge of the physics involved, but it looks like the projection style that is used has a very limited field of view that won't be resolved with more processing power. I don't see how shrinking the optics could help this. Because of this, it looks like future immersive improvements will be restricted, but I would be very happy to have it explained to me why I am wrong :) Edit: my pessimism around FOV was from reading this: http://doc-ok.org/?p=1274

It's as much holographic as the Oculus (or other head-tracked HMDs), and the missing depth cue (accommodation) doesn't seem very important in practice. See here [0] for a good discussion on what is and is not holographic, in the context of the HoloLens, from an academic VR researcher. [0] http://doc-ok.org/?p=1172

The reception has been in reaction to some very fake videos--they don't show the limited FOV, and they make the projections appear opaque even under bright stage lighting, which they aren't. Here is a video showing a third person view of the FOV; it is a bit unfair when objects are really close, because they are at the small end of the frustum pyramid, watch to the end in the immersive environment part to get full picture of how small the FOV is. https://www.youtube.com/watch?v=syFRdNs68s4 Blog post detailing the FOV measurement that went into making the video: http://doc-ok.org/?p=1223

Here is a link to Part 1: http://doc-ok.org/?p=1095 Doc-Ok (and others) are getting closer to reverse engineering the Oculus DK2 so hopefully we can have an open source Linux SDK soon. Maybe even before Facebook/Oculus releases their official version! We are looking for more help, so if you're on irc, pleaes join us in #openhmd on freenode.net

I believe[1] that the head tracking qualifies it as holographic. That light field stuff looks super interesting... 1. http://doc-ok.org/?p=337

You are making a bold and incorrect claim. """vergence-accommodation conflict, which causes a lot of the motion sickness, headaches, eye strain and other issues people have with VR""" This is untrue. It actually a pretty minor amount of the issues. There are individuals that suffer from this disproportionately but the estimates I've seen were in the low single digits. The major issues are in the source to the link you posted - http://doc-ok.org/?p=1602 """Accommodation-vergence conflict is the one remaining aspect of vision that is not simulated by current VR headsets. While it is not as big a deal as simulator sickness induced by poor tracking, high latency, or artificial locomotion, """ These are the major sources of vr discomfort which are increasingly handled by the baseline vr specification being increasingly in the reach of more and more hardware systems. I'd also note that as the poor tracking and high latency issues have disappeared people have found they are comfortable with radically wider ranges of artificial locomotion styles. At this point, in my opinion, the utter uselessness of any text based applications (ie what people actually DO all day long) is what is holding VR back. The resolution needs to scale up fairly radically. This monitor may have better text results but its not clear what the boundaries of it as a 3d display are as I haven't seen a review from knowledgeable sources (Oliver Kreylos/ docok is one of the people that I'd like to hear from).

Here is the DocOk/Vrui post on latency, A Trip Down the Graphics Pipeline (2014) http://doc-ok.org/?p=1057 (from which the reddit-linked graphs came). Highlights include: > Under a non-compositing window manager, regular double-buffering under OpenGL does not incur undue latency (and there is a window manager hint to tell a compositing manager to grant pass-through to a window). > At least using the Nvidia graphics driver [...] OpenGL can vsync to any connected display, primary or secondary. > OpenGL and X Windows allow applications to draw directly into a video controller’s frame buffer, allowing single-buffered rendering and racing the video controller’s scanout. [...] With front buffer rendering, display latency on the Rift DK2 dropped to about 4.3ms And from Zero-latency Rendering (2015) http://doc-ok.org/?p=1313 > with some new rendering configuration options in Vrui 4.0 I can disable vsync, and render directly into the display window’s front buffer. In other words, I can let these applications “race the beam.”

From that post: http://doc-ok.org/?p=824