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Design considerations for VR experiences

Discussion in 'Game Design' started by Martin_H, May 16, 2018.

  1. Martin_H

    Martin_H

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    I've once read an article about VR drawbacks, written by someone who had lots of hands on VR dev experience from a military background (meaning it reached far back before rift and vive were released and the hardware used was much more expensive and specialized) and he said that the disconnect between the focal distance of the eye and the virtual distance of things is a huge issue that current gen consumer hardware does not address at all.
    Now the first announcements for the Oculus Rift 2 state they have a solution for that by moving the lenses inside the device with motors.

    I'm considering designing something for the Oculus Go, and wonder if it's worth considering setting the main "focus" of visual content and interactions at the native focal distance of the HMD, to minimize discomfort for the players. Basically take the device's limitations into account as soon as possible, and design an experience around that from the start. And currently when I used the Oculus Go and go back into the real world, I feel all kinds of weird, including what I perceive to be issues with focussing my eyes on my screen. I wonder if that would go away with vr experiences where you look at the "right" virtual distance most of the time, but I can't find any mention of how far the display of the Oculus Go is actually focused. Does anyone here know? One article I've found says it's varied by motors, but I'm 99% sure that was bullshit and it's fixed, but the actual range I could not find out.

    I feel I should add an anecdote from my early artist days, where I was part of a community of illustrators.
    When you look at a painting and relax your eyes to go out of focus, you have an easier time judging the "big picture aspects" and overall light/dark distribution of colors, without the distraction of all the fine detail. Let's call this the "blurred vision trick".
    There once was a brief fad where photos were taken in such a way from 2 separate eye viewpoints, that you could see a 3D stereoscopic image on your screen, by looking at it crosseyed and refocusing your eyes to a distance that doesn't match the point in space they both are "looking at".
    When we talked about it, one person said "careful with that, I remember the story when one of us overdid it with the blurred vision trick, and couldn't focus his eyes clearly anymore for a day".

    You see what I'm getting at? The health implications and longterm effects of these things are not yet well researched. I doubt half an hour of VR a day is worse than staring at a screen for 12+ hours a day, but if there's a kind of experience that has a good chance of being both more comfortable and healthier for your eyes, I'd like to know what it is.
    Btw.: I've stumbled over an article about early research indicating that VR use for children may even be beneficial for their eyes, compared to using phones and tablets, and that got attributed to the focal distance the eyes adjust to while using the different devices. So I do think there's indication that longterm physical changes may be happening there, and they must not necessarily all be bad.

    Alternative thread title: Could VR make you blind? The answer will shock you!
     
  2. JoeStrout

    JoeStrout

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    There are definitely no motors in the Oculus Go. That's a feature in their speculative next-gen prototype.

    This document discusses the focus/vergence issue, and suggests that 1 m is a comfortable distance for content you're going to be looking at for an extended period of time.

    I tend to think the evils of decoupling focus and vergence are overblown; this is just something you can learn to do, and is no more dangerous than learning to wiggle your ears or whistle (none of which is a "natural" skill for most people). But certainly, it will be most comfortable where you don't have to work at it, which is what that 1m distance is aiming for.
     
  3. Martin_H

    Martin_H

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    Thanks a lot! Lots of good info there.
    But "Many have found that 1 meter is a comfortable distance for menus and GUIs that users may focus on for extended periods of time." sounds rather anecdotal and I think this document is not specific to the Oculus Go, and the Oculus Rift could potentially have a different focal distance. At the end they mention features that are only possible with the Rift: "This complicates interactions that involve ducking low or picking things up from the ground."

    I've heard in a GDC talk that certain throat cancer patients need to force themselves to still swallow a sip of water or similar in spite of all pain in regular intervals, because otherwise the body can "forget" how to swallow, and that ability might get lost permanently, even after a possible remission of the cancer. The whistling and ear wiggling don't interfere or overlap with natural reflexes, so I doubt those examples are 100% comparable to the eye thing.
    But then again, VR might as well be beneficial, we don't know for sure yet.
     
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