jitter

6 Topics

Moving Grabbed Objects jitter (Unity)
Using Unity 2018.4.5 and Oculus 1.38 When I hold an object (simple scene with just a cube) in my hand, then the movement of this grabbed cube is very jittery and not smooth at all. Using OVRPlayerController with LocalAvatar in TrackingSpace and AvatarGrabberLeft and Right inside this LocalAvatar. I set the Fixed TimeStep in the Project Settings to 1/72 (0.01388889). I uploaded a video of this behaviour: https://youtu.be/AoJ_d0d2Dq8 It's not as obvious in the video as it is in VR, but I think you do see the issue at the edges of the cube with the stuttery movement. Interestingly, when I throw away the cube, the movement is smooth. Also the movement of my hands is smooth, it's only the object I'm grabbing that stutters. Any idea how I can prevent this? Thanks!
mmchickenshack
9 months ago Place Quest Development
12KViews
2likes
19Comments
Meta Quest Browser Bug - 3D Scene Jitter - Developer - THREE.js
We are reporting a bug and seeking help. It is most likely a bug of Meta Quest Browser or related infrastructures. we are developers making 3D VR browser based Apps. We open our 3D Scenes (rendered by THREE.js) in Meta Quest Brower. The issue is, we notice that the scene would jitter even for the simplest example link from THREE.js official website. To reproduce, just open the following link in Meta Quest Browser and use controllers to drag the scene to rotate. https://threejs.org/examples/#webgl_animation_keyframes Jitter will likely to show up (not every time but pretty frequent). We believe this is more likely to be a bug of quest/browser other than the web page because the web page is simple and good in every other desktop/mobile browsers. One hint is, the jitter seem only happen (or much more frequent) when Passthrough mode is turned off. If you can not reproduce please refer to this video - it's captured by phone directly into the quest lens.: https://www.youtube.com/watch?v=hEha6OoYvyA This issue currently impacts our app badly - if anyone knows anything please let us know. Appreciate so much!!
maxkickass
1 year ago Place Quest Development
424Views
0likes
0Comments
Delta time variation jitter (caused by decoupled fixed time loop)
Hi developing a game for Oculus Quest 2 and have some problems regarding jitter in movement that is caused by a variation of delta-time. The jitter started when I introduced a fixed time loop of heavy operations. In my case I introduced a networking library that runs 60 times per second and therefore added some lag-spikes in the interval. But I have also added some artificial delays (sleep) to unitys-fixed update and notices the same behavior. My game still runs in the expected time-frame of 90 fps, but some frames take about 11 ms and others about 5 ms (example) which makes for a big variation in delta-time. Variation in frame-times has not been a problem in traditional pc games I have worked with before. The delta time is either made almost constant by the use of v-sync. Or necessary to variate to compensate for the variation in time between each presentation of the frame. And movement results are smooth. However it seems to be handled a bit differently on the Quest platform, I believe v-sync is not enabled, and instead Oculus use something called "OculusRuntime.WaitToBeginFrame" to keep a fixed frame-rate. The key difference is that "WaitToBeginFrame" is called in the beginning of the frame instead of how v-sync is called after the frame to do the actual waiting. I guess it is made this way to create as little input latency as possible before each rendered frame. I also assume by looking at my profiler data, that the time to wait in "WaitToBeginFrame" is calculated based on the length of the previous frame. This would work great as long as frames are equally long but with variations in frame-time (as I have when introducing a decoupled network loop) this introduce even more variation by making a frame that already takes more time then the previous wait for the time saved by the previous. So the problem I have now is that all movement that is moved in normal update by delta time is very choppy and jittery. It almost looks like the object is in two places at once because of the delta time variations. I am not sure how to fix this, since this normally wouldn't happen in a traditionell game. Does anyone have any more insight or information that could help me? Have I understand correctly how "WaitToBeginFrame" works? TL;DR: Has anyone here had problem with stutter on Oculus quest caused by delta time variation, which are present because of heavy operations in fixed time loops (fixed time lag-spikes). And knows any way to deal with it?
RektGamesPetterV
2 years ago Place Unity Development
3KViews
0likes
6Comments
Black Artifacts and Jitter
Hi there! I was running my first quick test using Unreal and deploying to Oculus Quest. For some reason I am getting black artifacts and jitter on all my test levels. Here is a short Video I recorded to show this strange artifacts: youtu.be/Jjp8ekfTSwk What am I missing here and how could I fix that? Thank you so much for any little help! appreciate it!
Anonymous
6 years ago Place Quest Development
1.2KViews
1like
0Comments
Jitter moving a simple object using Unity in VR
I have a problem that I don't know because there are so few people who suffer it too. I am making a game where I need to move an object over the scene from one point to another using code. The problem is that when I see the object move using the VR glasses, I see the movement as with jitter and the faster it moves, that jitter gets worse. Note: I use Unity 2019.1.14 The code is very simple: **************************************************************************************** public class DesplazamientoPruebas : MonoBehaviour { public Transform[] puntos; public int contador = 0; Vector3 posicion; // Start is called before the first frame update void Start() { Application.targetFrameRate = 90; posicion = puntos[contador].position; } // Update is called once per frame void Update() { if( Vector3.Distance(transform.position,puntos[contador].position)<2 ) { contador++; if (contador > 1) { contador = 0; } posicion = puntos[contador].position; } transform.position = Vector3.MoveTowards(transform.position, posicion, 0.2f); } } ************************************************** This script is assigned to the object and I only observe how it moves when I start the game. I have tried to: Modify the time in the game preferences to leave it as 1/90 or 1/60. Change all playerSetting parameters following the Oculus recommendations. To move the object I tried Update () with time.deltatime FixedUpdate with Time.fixedDeltaTime LateUpdate with time.deltatime I have tried as functions: Transform.Translate Vector3.Lerp Verctor2.MoveTowards All with the same result . It doesn't happen to you? I would appreciate a help because I can't think of what else to do. Thank you very much!!
ttgjou
6 years ago Place Unity Development
1.5KViews
0likes
1Comment
Jerky Motion When Capturing VR Gameplay in 60 Hz
Capturing VR gameplay for a trailer in 60 Hz when Unity is locked to 90 Hz (Rift) results in jerky motion because of frame skips. How do you address this?
JonasNeuston
7 years ago Place General VR & MR Development
996Views
0likes
2Comments