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Comment by andybak | Hacker News Reader

I don't think there's a single comment here that's about the developer tools. It's all just people debating the merits of the Vision Pro and XR in general.

Again...

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It’s pretty boring because it boils down to “I can totally imagine myself doing X with a headset” and “I can’t imagine myself doing X with a headset” — the operative word being “imagine.”

I’d love to read a comparison between visionOS SDK and OpenXR from someone who has actually used the latter. I gather that OpenXR is lower level, but what exactly does that mean for an app developer? How much more work would it be to build a “spatial experience” cross-platform with OpenXR? What would the compromises be for both approaches? Would it be feasible to build an engine that runs on both platforms?

> I gather that OpenXR is lower level, but what exactly does that mean for an app developer?

Mostly that they won't be using OpenXR directly. It's a standardised layer that lets many kinds of tools and libraries make use of the same hardware.

Well, ok, but since the tools and libraries don’t exist yet… Instead of waiting for somebody else to build middleware and hope it will be good, what would it look like today to design and implement an app that works on both visionOS and OpenXR?

That’s a question that I find interesting. Even if I don’t end up building such an app, it would illuminate the differences between Apple’s SDK and the rest of the industry.

A lot is still just becoming more clear now the SDK is here today but as usual there are definitely fine print gotchas. There are waay more restrictions in the MR Shared space mode so whatever (Unity/webXR) exports only to RealityKit for rendering with tight Apple conditions. In Full VR mode without Passthrough you have full control so custom shaders but no gaze and a 1.5m motion range limit. The MR mode itself has two flavors single or multi app modes with some tradeoffs like no hand joints with multiapp. Hand Joints are non OpenXR standard so need translation to be crossplatform anyway. And so on. All that said it's great so many experiences can port and there is a lot more interest in WebXR now hopefully WebGPU will fall into place too and it will be interesting to see what we can do with the Internet in 3D.

> but no gaze

In the WWDC unity-metal demonstration they definitely seemed to have gaze tracking. Have you checked looked through the sdk and confirmed that there is no public way to do this?

Yah, its very easy to get confused by them chopping all the sessions up for the conference. It was a little frothy but my understanding now is Gaze is provided in both MR modes known as Bound and Unbound volumes. So look and click works fine. In bound volume you don't get head or hand pose or room geometry. In the Fully immersed VR mode you don't have gaze data for understandable privacy reasons although room geometry could be handy but if it really matters then you build to MR targeting the more restrictive OS requirements like Unity Polyspatial and only Shader Graph.

Even the Unity team had to correct a few edge cases around WWDC as the sessions dropped:

https://twitter.com/pvncher/status/1666476686576332800?t=9Br...

I don't think that tweet thread addresses gaze in particular? Is there a particular tweet I should be looking at or is it just asserting the (absolutely correct) assertion that it's confusing?

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I'm specifically talking about the "Bring your Unity VR app to a fully immersive space" WWDDC talk, which claimed to be built on Metal and ArKit, and had a very very brief demo in it talking about gaze, screenshot here: https://media.hachyderm.io/media_attachments/files/110/520/9...

Note the demo wasn't actually on-device, and gaze was just following where the screen was pointing, so it's definitely possible I'm reading too much into this.

No I am sure they don't give you access to the Passthrough data or gaze details to the app in VR mode unless there are quite a few people wrong on this too. And since in VR you are completely outside the rendering subsystem I don't even know how you would interface whats in your app and the gaze hover trigger etc. My guess is the slide is referring to the MR unbound mode (full space they can call it to muddy the water). I would definitely be interested to know I am wrong here.

See this : https://twitter.com/Tojiro/status/1667028702734209025?t=1SnM...

EDIT: Checked with our team and so VR mode gaze has event triggers on any Apple UI object without exposing the details so that works unless your UI is not easily portable. And that's the same across all MR and VR modes.

I have a Valve Index and I’ve watched movies in a virtual cinema many times, most of those with friends. It’s immersive but becomes a bit of a sweat box after a few hours. The FOV and resolution are lacking and I can’t use it for virtual monitors. I can see this device fixing most of those problems if the specs are true. But I don’t see myself taking it out in public. That’s laughable. And I’d only drop that price if I was sure that the ecosystem is relatively open.

Honestly, sometimes I question how much this site is really “hackers”.

I downloaded the SDK and gave it a try. It was pretty seamless to get the sim booted up. However I did have trouble getting any of my hobby apps to build for the native SDK. A lot of libraries will need to add target conditionals to build natively. I finally got one of my most simple apps running, and SwiftUI does translate pretty well into it, but there’s still a bit of visual jank that I guess I could probably learn how to fix. The simulator also does seem kind of slow and unresponsive; I wonder if that’s at all representative of the final OS.

I just came here to see if anyone else was having problems get it g the simulator working/ if anyone else had experienced the same error…

I think discussions around potential behavioral impact of this tech category is a must, particularly with the existing forces at play that subsidize the literal engineering of addiction.

Yes but not when it happens repeatedly, covering the same ground and obscures discussion about the specific content being posted. It happens with every post about Google and every post about Microsoft and it is mostly just people covering the same ground again and again.

This just tells us that this version of Apple's Vision product line up is for the rich tech bros here and is not expected to be used by the general consumers who won't throw $3,500 on a XR headset just like the Hololens.

Clearly in the comments it just shows how out of touch they are in reality. There will be a version of the vision product line-up that will be reduced to the size and naturalism of a pair of glasses with some AR and reduced XR capabilities. But that is 5 - 10 years down the line or possibly could be quicker than expected.

Who knows, but this first version isn't it. This one is for the devs and techies only.

Recent rumors point to Apple unveiling a cheaper variant for the second gen.

https://9to5mac.com/2023/02/23/apple-headset-cheaper-second-...

Did you just respond to my comment complaining that people weren't discussing the SDK by... not discussing the SDK?

I've read a hundred general comments about Apple's strategy and market fit. Can we just talk about the actual topic of this post for once?

I personally think AR is mostly for techies/nerds/gamers, and professionals.

Doing CAD work in AR with a $3500 devices is worth it for any businesses.

Even as a sale tools when selling large products (cars, boats, etc.) without the need for stock. i.e. I can go to my local dealership, and look at their new model in persons. Then play with AR to decide which options I want for the colour, wheels, dashboard, etc.

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