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Comment by rocky1138 | Hacker News Reader

A friend came up with the idea of using a QR code sticker on the front of the unit, tracked by the laptop's webcam as you play. This way, you can detect the angle and distance from the laptop and do positional tracking.

Anyone wanna take that on and see if it works?

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As I understand, the issue is not so much getting the position data, but getting the data quickly (with low latency) to reduce mismatch between the rendered position on screen and the user's actual position. The Rift has special 250 Hz position sensors for this purpose, and even that's not fast enough. Webcams are usually only 30Hz.

http://oculusrift-blog.com/john-carmacks-message-of-latency/...

Fair enough. What about interpolation?

How many frames of delay do we get then. About 8 to 9. Not really useful with realtime games.

Where does most of the delay come from? Is there a way to take a "cockroach" nervous system approach where certain sensors have as direct a connection as possible to the code that updates the view of the user?

You might be interested in the articles Carmack[1] and Michael Abrash[2] have written about VR.

[1] http://www.altdevblogaday.com/2013/02/22/latency-mitigation-...

[2] http://blogs.valvesoftware.com/abrash/latency-the-sine-qua-n...

How low is the latency on measuring muscle movements like the Myo does? Is it competitive with the 250 Hz position sensors?

That sounds like a great use for Bokodes[1] rather than QR codes. Bokodes can display different information depending on the angle they're viewed at.

[1]: http://web.media.mit.edu/~ankit/bokode/

http://en.wikipedia.org/wiki/Fiducial_marker

Distance and angle with respect to the laptop would be the immediate and most dramatic drawbacks. Also the fact that image processing is a lot slower than using on-board high-speed sensors.

Of course, but we're at that sort of hack-it-together stage with respect to VR anyway. It might be cool to see it actually work, even if it's slow and clunky.

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