John Carmack's VR head set

Discussion in 'PC Hardware, Software and Displays' started by eastmen, Jun 7, 2012.

  1. Arwin

    Arwin Now Officially a Top 10 Poster
    Moderator Legend

    Joined:
    May 17, 2006
    Messages:
    18,762
    Likes Received:
    2,639
    Location:
    Maastricht, The Netherlands
    0 seems impossible as the fastest LCD pixels have been managed to shut off is 2ms apparently, according to Wiki (while 8ms+ is still happening). Of course, at 8ms in theory you can get to 120 refreshes p/s, but if the pixel doesn't manage a full off (I think many pixels are still somewhat more lit then off at that point, often half values being considered acceptable?), that's still a limitation. All the additional scaling and processing delays comes after that, and that is far too often 40ms or more in total.

    Since I have the Vita I've become more aware of this than previous. But Foosball 2012 on the PS3 was also interesting, as because it has almost no controller assists on the move controller, the lag when using the Move controller seems to be extremely low, 66ms or maybe even 50ms (which would be one of the very, very few games at that response time if true).
     
  2. MfA

    MfA
    Legend

    Joined:
    Feb 6, 2002
    Messages:
    7,610
    Likes Received:
    825
    You can't get transition time to 0, but you can get input-output delay from HDMI to screen to defacto 0 (overdrive can be implemented with a purely causal algorithm, even though not all manufacturers do it, lookahead is not strictly necessary).

    If you can use a TN screen then really compared to other delays in the system even with transition time it's all close enough to 0 not to matter (colour/intensity angle dependence is not necessarily a problem ... the angles to the eye are fixed, in theory you could compensate).
     
  3. Dominik D

    Regular

    Joined:
    Mar 23, 2007
    Messages:
    782
    Likes Received:
    22
    Location:
    Wroclaw, Poland
    I was referring to LCD TVs. You rarely connect bare LCD panel to PS3/360 and do all the plumbing yourself, don't you?
     
  4. MfA

    MfA
    Legend

    Joined:
    Feb 6, 2002
    Messages:
    7,610
    Likes Received:
    825
    This is however a thread about the oculus rift, and the current discussion started when I responded to the claim that OLED would solve latency problems for VR ... which it doesn't, because as I said, latency is mostly in the rendering, not the screen.
     
  5. itsmydamnation

    Veteran

    Joined:
    Apr 29, 2007
    Messages:
    1,349
    Likes Received:
    470
    Location:
    Australia
    No that was only part of what was said. Feel free to go tell Carmack he is wrong, we are just the messengers, he was adamant throughout the entire keynote that as displays it exist and it's a problem.

    What was also said is that John Carmack thinks that most traditional LCD screens have a big problem with stereoscopic 3D. He gave two main reasons ;

    1. They can't do true black (off).
    2. The grey to grey latency is too high causing ghosting effects.

    I'm guessing you haven't watched it yet, he does go into quite a bit of detail about it and it was very interesting to watch. So you should watch it, that way you can argue with John and not us :smile: .
     
  6. Dominik D

    Regular

    Joined:
    Mar 23, 2007
    Messages:
    782
    Likes Received:
    22
    Location:
    Wroclaw, Poland
    Chill, itsmydamnation. There's really nothing to argue over. :) MfA is correct in at least one thing - I did not review the flow of the entire conversation. There are actually two "threads" here in, not one: one about the viability of LCD TVs, another about LCD displays themselves and feasibility of these in VR headsets. Both got confused at one point and here we are.
     
  7. itsmydamnation

    Veteran

    Joined:
    Apr 29, 2007
    Messages:
    1,349
    Likes Received:
    470
    Location:
    Australia
    I'm completely relaxed and my post isn't supposed to be aggressive or defensive in any manner. Reality is i dont have an opinion because I haven't tried all these different screens in a headsets, John has. John has said its a problem for LCD's there's no point arguing with us about that.

    He explicitly states that when you try the RIFT that the three major problems are:

    1. Screen resolution
    2. The LCD latency causing ghosting in 3D
    3. Head tracking when you do more complex head movements or things like to were standing your now sitting.
     
    #47 itsmydamnation, Aug 6, 2012
    Last edited by a moderator: Aug 6, 2012
  8. MfA

    MfA
    Legend

    Joined:
    Feb 6, 2002
    Messages:
    7,610
    Likes Received:
    825
    What does that have to do with anything? You weren't discussing Carmack in general, you were replying to Billy Idol ... who said :
    "His enthusiasm during the keynote really got me to the point where I want VR gaming myself...but it seems that the tec is still far away. I think he is right, that one of his major concerns is simulation sickness. The smallest movements of your head need a consequence in the simulated world."
    Billy Idol was talking about VR specifically ... or in other words, HMDs ... the problems traditional LCD screens have with shutter glasses are neither here nor there, and OLEDs do not solve the fundamental latency problem Billy Idol was talking about (since rendering latency is the largest part of it).

    As for Carmack, where exactly did he call response time latency?
     
  9. DieH@rd

    Legend

    Joined:
    Sep 20, 2006
    Messages:
    6,387
    Likes Received:
    2,411
  10. Davros

    Legend

    Joined:
    Jun 7, 2004
    Messages:
    17,884
    Likes Received:
    5,334
    Its been around for ages
    Cat Stabilization was First pioneered by Eddie "The Eagle" Edwards during the 1998 winter Olympics
    [​IMG]
     
  11. Arwin

    Arwin Now Officially a Top 10 Poster
    Moderator Legend

    Joined:
    May 17, 2006
    Messages:
    18,762
    Likes Received:
    2,639
    Location:
    Maastricht, The Netherlands
    How cute ... !

    I'm about to get my 10 yo cat from the vet, had to have one eye removed (virus induced cancer :( ), looked just like that one when I got him first (though he was a mess, stray cat in bad condition, cleaned up nicely though stunted in his growth).

    Anyway back on topic:

    http://nl.hardware.info/reviews/283...ratie-testresultaten-reactietijd-en-input-lag

    shows that 0-100-0 pixel values for panels are indeed not great in general, much worse than I thought, and IPS panels are worse. So there is indeed an important win here for OLED.
     
  12. MfA

    MfA
    Legend

    Joined:
    Feb 6, 2002
    Messages:
    7,610
    Likes Received:
    825
    Also shows that plenty of monitors have 0 input latency nowadays.
     
  13. pcchen

    pcchen Moderator
    Moderator Veteran Subscriber

    Joined:
    Feb 6, 2002
    Messages:
    3,018
    Likes Received:
    582
    Location:
    Taiwan
  14. Arwin

    Arwin Now Officially a Top 10 Poster
    Moderator Legend

    Joined:
    May 17, 2006
    Messages:
    18,762
    Likes Received:
    2,639
    Location:
    Maastricht, The Netherlands
    And so TVs could and should have too ...
     
  15. Trunks0

    Newcomer

    Joined:
    Nov 16, 2006
    Messages:
    2
    Likes Received:
    0
    Location:
    Vancouver,B.C.,Canada
    and his results on input lag conflict with TFTCentralUK's review's test for the Dell U2212HM, BenQ GW2450HM & Asus ML239H. *shrug*
     
  16. hughJ

    Regular

    Joined:
    Feb 7, 2002
    Messages:
    861
    Likes Received:
    417
    Anyone have an educated guess as to what sort of rendering load and resulting new/different bottlenecks there would be with this method of split screen stereoscopy? Being that each field is doubled, but half the pixels, any sort of per-pixel shading/texturing/etc should be roughly the same pixel load as having just a standard single full frame? Scene geometry would be presumably doubled though?
     
Loading...

Share This Page

  • About Us

    Beyond3D has been around for over a decade and prides itself on being the best place on the web for in-depth, technically-driven discussion and analysis of 3D graphics hardware. If you love pixels and transistors, you've come to the right place!

    Beyond3D is proudly published by GPU Tools Ltd.
Loading...