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Jutter must die!

Scofthe7seas
Level 2
Ok, I know this has been brought up here and there, but I think isolating and fixing the jutter issue should be a huge priority. We need to figure out exactly what is causing it, and see how it can be worked out for EVERYBODY on all applications. First of all, we need to gather basic information about the issue.
In case you don't know, jutter is a weird leaping of movement when looking around in the rift. I suppose it could also be called stutter.
Does everybody have jutter to one degree or another? Are there some people who have no idea what it is, and have never seen it? If so, what setup are you using?
For me, I have an Nvidia 780GTX and in Intel 2600k i7 at 3.5, 16 gigs of ram. My main monitor is a TV running at 60Hz. I don't experience jutter in everything. The DX11 forced mode fixes many experiences for me (dreadhalls, cyberspace, helix). There are no framerate issues when jutter is present, because framerate shown is typically well well above 75. There is mostly no jutter on applications that go direct to rift.
Some demos have jutter no matter what the setup is. Sightline is one of them, though jutter can be minimized by making the rift the primary monitor (and in Nvidia, it doesn't hurt to set "run at highest available refresh rate in Nvidia control panel.)
Minecrift gives me jutter under every circumstance. I even set the rift as my ONLY monitor and it still happened.
I've heard some people say it is a problem with Timewarp, but if it is, shouldn't it be an issue affecting everybody? And also, if it is, does that mean it is inherent in the SDK? Both Quake rift conversions have timewarp settings, and I have experienced NO jutter in either of those games.
I have no intention of seeming demanding. I just believe as a community we can narrow down the root of this issue by sharing information in one place, instead of it being mentioned here and there in various threads for various demos/applications. Together, we can put a stop to this menace!
62 REPLIES 62

davidjc
Level 2
Someone had seemed to isolate the problem on Reddit. I think that Oculus must know what is causing it as well. Waiting to see what the next SDK looks like though.

Cgpnz
Level 2
"davidjc" wrote:
Someone had seemed to isolate the problem on Reddit. I think that Oculus must know what is causing it as well. Waiting to see what the next SDK looks like though.



please link

zork2001
Level 7
This jutter is ruining everything. I am getting it on more than half the games. It also does not matter if it direct to rift or Extended desktop. Actually all the Extended desktop ones I have tried on the page below all have jutter and I tried every variable desktop combination I could to get rid of it and it is a no go.
viewtopic.php?f=42&t=12646.

Direct to rift games it’s about 50/50. At least there a few games that work right so I know how it is supposed to look like otherwise I would think the rift was a huge over hyped piece of crap.

MikeF
Level 10
Yeah this is currently #1 on my list of issues. So far the only thing that i can get running without this happening is the sdk tuscany demo, config utility and hl2.

What i dont understand is that i've had moments in hl2 where my fps dropped below 75, but instead of intense judder it just drops in framerate like it would on a traditional monitor so it cant be FPS related (at least on my system)

I hope this gets sorted as it really makes it a pain to develop on

jngdwe
Level 3
If your computer is capable of the 75Hz solid, then the only jutter seams to be coming from a mismatch in the refresh rate. That is literally the only problem I have with the DK2 performance.

Dave
Level 3
The word is "judder".

Scofthe7seas
Level 2
"Dave" wrote:
The word is "judder".


Well, I suppose that does invalidate everything I've written about it.

Wireline
Level 3
Reading Michael Abrash's blog, he says judder is unavoidable unless refresh rates get insanely high. Its long and complicated, but he describes it as being an artefact of the human visual system and is caused when you have relative motion of the eye across a virtual object. I will confess to only peripherally understanding it, but I got the impression that there is no simple fix to it.

An important distinction - I believe there is a difference between "stutter" and "judder", with the former being more to do with a low frame rate. They just happen to look very similar, a kind of scraping or jerkiness when you move your head. (EDIT: Thinking about it, they are essentially the same thing - low frame rate leads to lower refresh of each pixel, just as low refresh does, hence more time each pixel stays "on". Two different causes, same result)

Link to the Abrash blog piece: http://blogs.valvesoftware.com/abrash/why-virtual-isnt-real-to-your-brain-judder/

I think the industry is already working pretty hard on it though 😄

zork2001
Level 7
That is not the problem, The problem is happening when it gets pushed to the rift. If you were to look at your monitor showing the rift display and moved the rift head display to look around it is smooth. If you take the same scene push it to the rift – take the lens off the rift to look at the display you get judder on head movement.