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How does the Hololens 2 matter?

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Re: How does the Hololens 2 matter?

#71

Post by aaaaaaaaaaab »

Eh... the author doesn't know how to compare solid angles.

Anyway, I wonder what happens when VR manufacturers increase FOV to the point where the distortion from the traditional perspective transform (homogeneous linear transform) becomes impractical due to distortion towards the edges (example: https://www.youtube.com/watch?v=ICalcusF_pg).

You need >120 FOV for an immersive experience, but current graphics pipelines are built on the assumption that straight lines in world space map to straight lines in screen space, so you can't do proper curvilinear wide-angle perspective with the existing triangle rasterizer architecture.

Re: How does the Hololens 2 matter?

#72

Post by majewsky »

bluesign wrote: post #70
lwansbrough wrote: post #68

I left this comment in a prior HoloLens related thread on HN the other day, but I'd like to reiterate (so I'll just copy/paste it) so I can get some more opinions on the concept. I'll add that the functionality I describe below would have limited use cases without a GPS or a device that's really useful/wearable outdoors and available to the public. But I think this should be the long term vision for holographics, as…

It doesn't matter if it is 'layers' or 'apps' basically the problem begins when you have more than one layer/app at a time. So I guess for a long time we will stuck with one app a time, and some kind of manual switching. Also there is privacy angle, I don't think nobody wants pinging their location all the time, maybe some QR code/ beacon solutions can help, but I am not much optimistic there too.

> Also there is privacy angle, I don't think nobody wants pinging their location all the time, maybe some QR code/ beacon solutions can help, but I am not much optimistic there too.

Maybe you could have something like K-anonymity? You discretize your location into chunks of maybe 100x100 m, take the hash of the chunk ID, and request results for all chunks whose hash starts with the same 4 or 5 digits as your chunk's hash.

Would probably require some more thinking since a consecutive series of requests for adjacent chunks could be used to uncover which particular chunks you were interested in.

Re: How does the Hololens 2 matter?

#73

Post by hyperknot »

aaaaaaaaaaab wrote: post #71

Eh... the author doesn't know how to compare solid angles. Anyway, I wonder what happens when VR manufacturers increase FOV to the point where the distortion from the traditional perspective transform (homogeneous linear transform) becomes impractical due to distortion towards the edges (example: https://www.youtube.com/watch?v=ICalcusF_pg ). You need >120 FOV for an immersive experience, but current graphics pipelin…

Check out 360 degree Panorama formats, especially "Cubic" [1]. A similar approach was used back in 1992, in CAVE [2], using 6 virtual cameras.

[1] https://wiki.panotools.org/Panorama_formats#Cubic [2] https://en.wikipedia.org/wiki/Cave_automatic_virtual_environ...

Re: How does the Hololens 2 matter?

#74

Post by abainbridge »

aaaaaaaaaaab wrote: post #71

Eh... the author doesn't know how to compare solid angles. Anyway, I wonder what happens when VR manufacturers increase FOV to the point where the distortion from the traditional perspective transform (homogeneous linear transform) becomes impractical due to distortion towards the edges (example: https://www.youtube.com/watch?v=ICalcusF_pg ). You need >120 FOV for an immersive experience, but current graphics pipelin…

> but current graphics pipelines are built on the assumption that straight lines in world space map to straight lines in screen space, so you can't do proper curvilinear wide-angle perspective with the existing triangle rasterizer architecture.

Isn't that approximation still fine as long as a single triangle doesn't span more than, say, 5 degrees of your FOV? If you are trying to represent a real scene, your triangles will rarely get that big. If you really want to display huge triangle, then you can just sub-divide it into a thousand smaller triangles.

Re: How does the Hololens 2 matter?

#75

Post by lwansbrough »

bluesign wrote: post #70
lwansbrough wrote: post #68

I left this comment in a prior HoloLens related thread on HN the other day, but I'd like to reiterate (so I'll just copy/paste it) so I can get some more opinions on the concept. I'll add that the functionality I describe below would have limited use cases without a GPS or a device that's really useful/wearable outdoors and available to the public. But I think this should be the long term vision for holographics, as…

It doesn't matter if it is 'layers' or 'apps' basically the problem begins when you have more than one layer/app at a time. So I guess for a long time we will stuck with one app a time, and some kind of manual switching. Also there is privacy angle, I don't think nobody wants pinging their location all the time, maybe some QR code/ beacon solutions can help, but I am not much optimistic there too.

If you own a cellphone you’re already carrying a device that pings your location all the time. I don’t think anybody actually cares enough to change what they’re familiar with, let alone some future potentially amazing technology.

Re: How does the Hololens 2 matter?

#77

Post by GistNoesis »

aaaaaaaaaaab wrote: post #71

Eh... the author doesn't know how to compare solid angles. Anyway, I wonder what happens when VR manufacturers increase FOV to the point where the distortion from the traditional perspective transform (homogeneous linear transform) becomes impractical due to distortion towards the edges (example: https://www.youtube.com/watch?v=ICalcusF_pg ). You need >120 FOV for an immersive experience, but current graphics pipelin…

>"straight lines in world space map to straight lines in screen space"

Then you post-process the screen space, with something like a fish-eye shader to warp your image appropriately. Sure you'll lose some resolution near the borders but the human eye won't care because it's not in its high resolution area.

Re: How does the Hololens 2 matter?

#78

Post by k__ »

I think it's like with VR, but a magnitude more expensive right now.

Hololens is the Vive/Rift of AR and Vuzix Blade is the Focus/Quest of AR.

No end user will buy a Hololens if it looks like that and costs thousands.

But something like google glass in good looking, with more power and good voice control could really replace Smartphone in the future.

Still the Hololens will sell to enterprise customers and AR play-rooms where you can use them for a small fee for an hour (like we have VR rooms right now).

So I don't expect much more from new Hololens generations than evolutionary improvements.

Re: How does the Hololens 2 matter?

#79

Post by icebraining »

goldfeld wrote: post #47
calciphus wrote: post #44

Earlier quoted context omitted.

Ever watch a bartender ring up a complex order? That's a domain where touch exceeds keyboard / mouse hands down. Digital art, such as drawing (or even just whiteboarding an idea). There is no one universally great input method.

Or a sufficiently complex establishment with a sufficiently trained bartender could do better with keyboard macros. Sure it may be rare but the point is touch interfaces have a complexity limit whereas keyboards and grammars don't.

How can a touch interface have a complexity limit that a keyboard doesn't? You can literally emulate a regular keyboard on a touch screen.

Re: How does the Hololens 2 matter?

#80

Post by hatsunearu »

abainbridge wrote: post #74
aaaaaaaaaaab wrote: post #71

Eh... the author doesn't know how to compare solid angles. Anyway, I wonder what happens when VR manufacturers increase FOV to the point where the distortion from the traditional perspective transform (homogeneous linear transform) becomes impractical due to distortion towards the edges (example: https://www.youtube.com/watch?v=ICalcusF_pg ). You need >120 FOV for an immersive experience, but current graphics pipelin…

> but current graphics pipelines are built on the assumption that straight lines in world space map to straight lines in screen space, so you can't do proper curvilinear wide-angle perspective with the existing triangle rasterizer architecture. Isn't that approximation still fine as long as a single triangle doesn't span more than, say, 5 degrees of your FOV? If you are trying to represent a real scene, your triangle…

You should still take it into account because when you move your head around it causes things to get warpy and it may be at best weird and at worst dizzy.
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