Comment by MarkMc
6 years ago
Interesting article. Here's Abrash's wry summary of the problems facing AR:
Leave aside the issues associated with tracking objects in the real world in order to know how to virtually modify and interact with them. Leave aside, too, the issues associated with tracking, processing, and rendering fast enough so that virtual objects stay glued in place relative to the real world. Forget about the fact that you can’t light and shadow virtual objects correctly unless you know the location and orientation of every real light source and object that affects the scene, which can’t be fully derived from head-mounted sensors. Pay no attention to the challenges of having a wide enough AR field of view so that it doesn’t seem like you’re looking through a porthole, of having a wide enough brightness range so that virtual images look right both at the beach and in a coal mine, of antialiasing virtual edges into the real world, and of doing all of the above with a hardware package that’s stylish enough to wear in public, ergonomic enough to wear all the time, and capable of running all day without a recharge. No, ignore all that, because it’s at least possible to imagine how they’d be solved, however challenging the engineering might be.
Fix all that, and the problem remains: how do you draw black?
What I find funny is that I believe he worked at Valve at the same time Jeri Ellsworth was there solving most of these issues.
Her new TiltFive system is "AR somewhere" rather than AR everywhere which allows it to provide a solid, practical, and affordable experience.
Here's a Tested review if you haven't looked into T5 before...
https://www.youtube.com/watch?v=Jse-GwkcYgI
Surprisingly enough all of the above is fairly well solved (or at least has the illusion to have been solved) in HoloLens and it turns out that not being able to draw black isn't a huge issue because AR is designed to interface with existing world and all virtual objects are ok to have grey instead of full black. If you were going to watch movie or play classic games, this would be an issue but that is not interfacing with the existing world and AR is not targetted for those use cases.
It's worth reading the article. "How do you draw black?" is a teaser for a much more insightful and nuanced (and convincing) treatment.
Here's a bit more:
Given additive blending, there’s no way to darken real pixels even the slightest bit. That means that there’s no way to put virtual shadows on real surfaces. Moreover, if a virtual blue pixel happens to be in front of a real green “pixel,” the resulting pixel will be cyan, but if it’s in front of a real red “pixel,” the resulting pixel will be purple. This means that the range of colors it’s possible to make appear at a given pixel is at the mercy of what that pixel happens to be overlaying in the real world, and will vary as the glasses move.
I'm not sure that this isn't solvable, having used a hololens, I don't remember this being an issue, and if it was, it wasn't one that impacted my experience.
> Fix all that, and the problem remains: how do you draw black?
This concern is technologically narrow-sighted. We already have VR headsets with forward cameras built in. If the real world image is a projection too, you can draw whatever you want, including black.
I have a first gen Gear VR and it has a camera passthrough mode where it will just turn on the camera and show it inside. I used that for about an hour and tried to do normal stuff in my apartment. Gave me one hell of a headache.
Oof yeah. Crazy as it might sound, it seems like the easier path to a complete solution is some sort of neural lace interfacing with the optic nerve. We're obviously not there today, but maybe by the end of the century?
I think this is one of Neuralink’s long term goals.