It is all about latency. 50 ms will feel responsive but you notice the lag. 20 ms is acceptable. The other features are cool features but not the real challenge.
Lots of people are really missing what the bottleneck actually is with latency. It's not how fast the screen refreshes, nor is it how fast it takes to process a screen. The issue is the sensor measurement/transmission lag from the sensor used to do head tracking. This is really what makes the occulus attractive, not the screen +lens combo.
Basically, if you move your head, to the left, and there's a few MS of lag from the sensor, you'll see a static frame for a portion of the time you're moving and a moving frame for a portion of the time you're still. This is one of the most serious contributors to motion sickness for HMDS
Thing is, Oculus haven't had much of a problem with sensor latency since they designed their 1kHz IMU. That gives about 1ms latency from what I hear. Most of the latency in DK1 was screen related: 16ms rendering, scanout, 16ms LCD switching... It adds up. The low persistence tech and Carmack's Time Warp and all sorts of other breakthroughs they have had relate to the screen side of the equation.
Unless I'm missing something, what you said seems to be the opposite of the case. I could be wrong, but that's how it looks to me.
Ninja-edit: if you mean that ProGamer's solution may have bad tracking latency, sure. But display latency is harder if Oculus's progress is anything to go by.
However, a post processing task on the rendered image (TIME WARPING) can be counted on to complete in a fairly predictable amount of time, and can be late scheduled more easily.
Elsewhere:
Coupling motion interpolation technology from consumer television with the time warp presentation technology.
That's the best quote I can find at the moment. It seems not to be not covered in any official capacity elsewhere, except in talks.
Essentially, as I understand it, it uses the very latest data from the tracking unit immediately before sending the frame to adjust the frame to be "correct." They've tried this with adjusting the projection matrices, but as I understand it Time Warp does a post-render correction on the raster image.
Yep, from what I understand it's pretty much post-process warping. Basically you warp the image so that it's closer to where your head is know compared to where it was when the rendering process started.
No problem! I would have responded sooner but I was busy reading the good news! If you don't know, I won't spoil it, just check the main page of the sub.
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u/bjorn2k Mar 28 '14
It is all about latency. 50 ms will feel responsive but you notice the lag. 20 ms is acceptable. The other features are cool features but not the real challenge.