VR impressions

Been testing my new Oculus Quest for past few hours, wanted to share some impressions.

• Looks like I started noticing pixels on Quest one or two hours in, but that's only if I focus on them.
• It feels that VR hardware needs a much wider field of view than what it currently offers. Currently the experience feels like you're wearing a scuba mask, or, rather, looking through binoculars. Smallish field of view greatly reduces area where binocular vision works. I think only half or even one third of visible area is truly sterescopic.
• Finger tracking is a great feature, but.
• For some reason many application get it wrong. For example, Oculus Interface fails to understand normal paradigm is pointing at buttons with your index finger, and instead you need to aim with your whole arm and pinch. This is odd. Hands are cool, but hand interaction with environment is done wrong.
• A lot of content fails to adjust to sitting posture and assumes that you have large play area. I feel like some games assume that where your headset is relative to the floor is your actual height, and if you're sitting in a chair, that can result in adventures of Gulliver experience.
• Likewise, correct portrayal of scale is very often overlooked. There's some great content in Oculus TV, documentary videos that have depth, and not just "surround video", but a lot of content appears at a wrong scale. For example, people being too small or too large is an incredibly common problem. It is not too bad, but it is slightly distracting, as you often end up in world of liliputians or something like that. Maybe there is a need for some sort of different video format that can adjust to user's differences better. Like, I don't know voxelized streams, semi-reconstructed scenes, and so on.
• Apparently in case of VR videos, 180 degree coverage ("half-sphere") provides more punch than full 360. Full 360 video has, for some reason, less pronounced depth and is often missing depth information altogether. And in case of 360 degree coverage you'r missing half of the content anyway.
• I also found visual style used by "animated experiences" in quest (or whatever their name is) to be very interesting. This reminds me of "another world" visuals. They're probably onto something. Seems those were made with Quill.
• It seems that it is easier for "non-advanced" computer users to use this kind of headset. I gave the headset to family members to play with "Elixir" demo (hand tracking), after some confusion, they had less difficulty adapting to the environment, I think.
• Apparently antialiasing plays much bigger role, due limited screen resolution. I've fired up sketchfab app in VR, and looks horrible, compared to other experiences for platform. It looks like sketchfab player didn't bother to implement antialising. Another possibility is low fps on some scenes rendered by Quest.
• Smallish text can look ... interesting at the edge of your vision, because displays are flat, and if text falls into binocular vision area, this can result in sort of incorrect overlap of pixels, causing some of them to, I don't know "shimmer" or take on silvery appearance.
• I think at some point we could possibly get some sort of "bug eye display" with screens being concave and focused around each eye, with wider view, but that's just a thought.

Thoughts?

 

Index has better field of view than Quest, and StarVR has even better. Problem with larger than lets say Index FOV is that you get super sensitive to artificial locomotion. And teleportaion is no fun. It can be solved, for example we have an option to reduce FOV while moving

I cant speak for Quest but PC headsets and software (its mostly a software issue) are fully stereo over the entire field of view. But your peripheral vision is not as sensitive as your center field of vision.

Yeah, scale is a problem for many devs it seems, even Half Life Alyx gets scale wrong. We have put in alot of effort to get it right. All items in hands are correct to the millimeter. We also try to scale environmental assets corretly., But sometimes they are a bit off. Almost no assets off the store are life size correct. They need work. Some even dontr have the correct aspect ratio, these are a pain to fix.

Yeah antialising is a huge thing in VR, thats why deferred redning is so hard to use. Most VR devs including ourself uses forward rendering.

Smaller text is actually OK on the index. We are soon getting to the sweet spot of VR HMD resultion, but we will need foveated rendering for performance reasons.

I'm sure there are RnD on curved displays and lenses for VR use, its just a question of time, but again, with wider FOV comes greater problems with sickness.

edit: also remeber, the Quest is not a 100% representation of premium VR on PC, while being very good for the price point.

 

They're not.

Binocular vision only works in area where "vision cones" from both eyes overlap. You cannot get full overlap with nearby objects when FOV is limited, because there will be a lot of missing data.


My impression is that VR works comfortably with objects at half of arm's length at best. Any closer than that and things start looking strange.

One other thing.

That's not where the scale becomes wrong. For example, if IPD is incorrect, or head is at wrong height, then the brain may perceive things at wrong scale, and having them modeled with millimeter perception won't matter. The whole world will look too small or too big.

This is what I experienced with 360 videos.

For example, Video of a Diver, a Shark... but with no depth information encoded. The diver is perceived as being 3 to 5 meters tall. Because the image is infinitely far away and has no parallax.

Video of Louvre Reconstruction - The director of Louvre is perceived as .... 100..120 cm tall person. This one's with full depth information. Apparently there's IPD mismatch between me and camera settings.

Now the fun part - video about some tigers (depth encoded, but apparently poorly) - tiger is seen as roughly 3 times taller than a house cat. Kinda small. Now, I bring up menu, and menu shows up in front of the tiger and tiger's perceived size baloons immediately, because now there's a reference that is correctly perceived by my binocular vision. The tiger now has 2 meter shoulder height, definitely.

This stuff happens everywhere.

The worst situation happens with games that do not recognize sitting posture and apparently decide that my eye height is my full standing height. This causes world to visually shrink.

That's the "scale problem" i've been referring to.

 

Index among others report the IPD and FOV (if you can adjust FOV on the headset) and the projection is corrected in the driver (SteamVR).

 

You can't correct human vision via a driver.

Given the FOV per eye, the area where vision is binocular will be lower than that FOV. Which is what indicated in the chart above.

Middle will be fuly stereoscopi vision, and the gray areas will be monoscopic side vision. This will be especially noticeable with large nearby objects.

--------

Or, rather than "smaller", you'll have parabolic areas that starts few centimeters in front of your nose, where you have full perception of depth. For distant objects this area will get wider and wider, for nearby it will be quite small.

 

You need to set the IPD to your correct IPD off course. Mine is 65mm.

Get a premium headset with mechanic IPD set it to your correct IPD and the scales will be correct, given that the dev's have correct scales

 

My IPD is correct. It is 70..72, by the way, and Quest has mechanical adjustment.

You don't get it. Honestly, you're supposed to understand it instantly.

Binocular vision requires two images of the same object from different angles.

And here's the illustration of the problem:

 

Im talking about scale. You are talking about overlapping vision cones, two completely different things. Again here Index is better btw, they have higher FOV, plus better projection where vision overlap towards nose.

Its the same thing in reality, close left eye and you will see right side of your nose. Close the other one and you will see vice versa side.

 

I'm talking about perceived scale. perceived scale is affected by many things other than IPD. I explained it in my previous post.

It doesn't matter how precisely your objects are modeled, if the user perceives the whole world as scaled up/down.

 

Also, I do not beleive that thread move was justified. It definitely should remain in general section.

 

A IPD of 70-72 mm is extremly high. I can guess the headsets have a problem with that

Here is my Index at your setting

And here at mine


The virtual nose (the area were there is no vision) is alot bigger on yours.

 

Hi,

My guess is that objects appears smaller in some headsets when they are trying to squeeze in more field of view in too small displays, and lenses. The distance between your eyes, and the lences, and wearing glasses, or optical eye lenses will also change the perceived scale.

Can't argue against what premium VR headsets need is peripheral vision, and some simple eye tracking to just render in high rez in the area where the player are looking.

 

I found a possible reason for objects appearaing too small. Apparently floor surface was placed too high. Sadly, Quest does not allow to manually adjust its height, and you need to move it by touching floor with the controller, and even in this case, it seems to be higher than where it should be by 1 or 2 centimeters.

 

Yeah, I know. That's one of the reasons why I got quest and not Rift S. After testing Quest in the store, it became obvious that my IPD is outside of recommended values for the S. And S does not even have mechanical IPD slider, while Quest does.

 

Yeah floor height is really important for stuff like doors, railings, basicly world objects. Items in hand shouldn't be affected though since these are free floating and does not rely on floor for reference.

Edit: though a sniper rifle with a long barrel can feel off since the barrel will have the wrong distance to floor when pointing down towards floor. Brain is super sensitive to anything being off

 

Can´t se how the position of the player camera above the floor could change anything but the perspective. Different distance to objects though, or the floor, will change the perceived size of each object.

 

Some more information (maybe someone is interested?)

Apparently VR sickness does get better with continued use, as I can now play blade and sorcery and alyx for prolonged time with smooth movement.
Unfortunatley, in case of alyx, it seems that after two hours of movement nausea and queasiness still kicks in, except it now hits like a truck.

I think oculus screwed up with USB connectors, as apparently it is quite difficult to find a USB-C-->USB-A cable that can handle required speed. "High quality" cables are ridiculously rare, it is unclear how to detect a cable without problems, as there are few reviews of cables by people who tried to use cable with Quest, but ran into problems. So, I'm stuck with Virtual Desktop streaming for PC use

 

If you have some spare time over, perhaps you could make some field studies to find out how a limited peripheral vision will affect your performance, or do to your over all comfort?

Just wear a diving mask, maby combined with a tube for each eye, to limit your field of view. Use that in some bussy situations, like judging a tennis match, or playing basketball, or just take a ride in a roller coaster.

To simulate so called fixed foveated rendering, I guess the field of view has to be limited even further by smudging the glasses with some hand cream to just leave a clear spot in the middle of your sight.

 

It's individual, some get their VR legs right away, some after a while, some never gain them. Reducing FOV does help. We have a option for that in our game.

 

No, I won't be doing that.

-----------

I finally found a decent cable and got oculus link working... only to discover that my GPU technically isn't supported by it. I have GTX 1060 3GB edition, and while it runs perfectly smaller applications, it runs out of VRAM and stutters on more intensive games, but only if it is working through Oculus Link, and if it is running through VR desktop streaming, it is perfectly okay.

However, now I see, or rather feel difference in latency. Streamed Alyx feels a bit more sluggish compared to USB cable connection.

--------
Can one of the moderators maybe move this back into general? I doubt this really belong to VR section dedicated to working with VR in unity. @zombiegorilla ? @hippocoder ?

 

Like closing your eyes, or looking through your fingers may make you feel more secure, instead of turning on the light when you are in a stressed situation caused by not seeing whats going on around you.

I child would also realize how constantly being forced to move the whole head to look around, like a maracas soon may induce motion sickness.

 

I'm pretty sure that ain't it.

VR motion sickness triggers when you are sitting/standing still, but the world in the game moves. I.e. "continous movement". Basically, player's head never really moves "like a maracas", unless the game developer did something stupid like requiring them to nod/shake head for yes/no response.

 

Just the fact of not having peripheral vision will increase the stress levels caused by not being aware of whats going on around you, or force you to move your head unnaturally to look around.

If reducing the fov further may make some people feel more comfortable. I think it's mainly caused by completely takeing them out of the situation, and more or less reducing the experience to just looking on a small picture.

Yeah, sure, too sluggish update of the headsets isn't good either.

 

I have not experienced anything that would support a hypothesis of "VR sickness" being connected to anxiety in any way.

VR sickness is dizziness, nausea, sometimes headaches. However, you can easily be nauseous and absolutely calm at the same time.
----------
A more interesting thing to poke at would be some people experiencing episodes of depersonalization/derelaization after prolonged use of VR. This is rarely mentioned.

For example:
https://www.reddit.com/r/oculus/comments/5j14ea/heavy_depersonalizationderealization_symptoms/

But feeling sick due to anxiety feels like a dud to me.

 

The most common form of VR sickness is similar to what you get when you read a book in a car.

Your visual cues and motion cues are not in sync, which introduces sickness

Edit: only time I have been feeling sick in VR was when I recorded this clip to show our physical head mechanic. Repeatingly letting my head getting out of sync does introduce sickness after continues repeating it

 

Imagine yourself walking through a dusky room like that, moving your head from 80 degrees left to 80 degrees right, looking up, and down, sometimes with your head at the same height as the office desks.

The lack of FOV is obvious. Just add some sluggish tracking of the headset, or delayed update of the display, and I can very well think some will puke after just a few minutes.

No frame rate in the world can compensate for bad tracking, or if updating of the displays is uneven, or not in sync with your movements.

 

What are you talking about? Thats the desktop view most of the VR headset FOV is cut away. It's not a problem looking around like that, premium headsets have 90 up to 144hz update frequency, more than enough to not cause any problem.

I talk about when the physical head hits a object in the world and desync from my real head position. Not a problem when actually playing the game, but when I recorded that video I did it numerous times to demo the physical head feature (most games goes black instead which is dumb) . That's the only time I have felt a little bit sick in vr

 

Ohh, when you get motion sick when reading a book as a passenger in a car. I think it's mainly caused by the book takes the most of your focus, making you lose track of whats going on around you.

For them who get motion sickness in VR (I’m not one of them), I think it also is caused by lack of perception what's going on around you. Limited peripheral vision is one reason, bad tracking of your head, or delayed update of what you sees in the displays are other reasons.

The signature neginfinity, seems to have identified problems with usb cables. Thats maby one reason for bad tracking, or uneven update of what you sees in the displays. Don´t think the cables have anything to do with the frame rate.

In the clip you demonstrates unrealistic and excessive movements of your head, which I think also may turn on the puke reflex.

 

Sorry that was two different things, reading a book while sitting in a moving car is similar too motion sickness in VR when using artifical locomotion. Your vision is moving so your brain get that information but your other senses do not get that since you are stationary. Similar to reading a book in a car, but in that case your vision get stationary information and your other senses get moving information.

The other clip was just an example of the only time I ever got motion sick in VR, I go around and bang my head against virtual items in the world to demonstrate our physical head feature. other games go black when you hit items with the head, we instead does not let you clip world items at all, but this means your head will desync from actual head position, not a problem when playing like normal, but when banging by head into items like that with repeated desyncs I got a bit motion sick

 

I'm aware of how you also noted a problem with 6 DOF tracking where hitting objects in VR is not physically blocking your movements IRL.

Blacked screen will definitely remove your visual cues, and sliding walls will probably give you an unnatural feeling. Have anyone tried the combination of sliding walls, and reduced FoV to break the VR effect? For example by using some heavy ”fixed foveated rendering” just in that situation.

 

A slightly different matter now..

Apparently Oculus has announced that every oculus Device would require a facebook login starting with October, while existing users will be able to keep their oculus account for 2 years. And here I am with my new Quest I was happy with.

That is a real disappointment.