[HN Gopher] Glasses-free 3D using webcam head tracking
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       Glasses-free 3D using webcam head tracking
        
       Author : il_nets
       Score  : 70 points
       Date   : 2025-10-18 12:07 UTC (5 days ago)
        
 (HTM) web link (assetstore.unity.com)
 (TXT) w3m dump (assetstore.unity.com)
        
       | il_nets wrote:
       | Hi HN, I'm Sten, one of the creators.
       | 
       | We built this because we wanted 3D experiences without needing a
       | VR headset. The approach: use your webcam to track where you're
       | looking, and adjust the 3D perspective to match.
       | 
       | Demo: https://portality.io/dragoncourtyard/ (Allow camera, move
       | your head left/right)
       | 
       | It creates motion parallax - the same depth cue your brain uses
       | when you look around a real object. Feels like looking through a
       | window instead of at a flat screen.
       | 
       | Known limitations: - Only works for one viewer at a time - Needs
       | decent lighting - Currently WebGL only
       | 
       | We're still figuring out where this is genuinely useful vs just a
       | novelty. Gaming seems promising, also exploring education and
       | product visualization.
       | 
       | Happy to answer questions!
        
         | jampekka wrote:
         | The demo gives just a blank screen on Android Firefox, Kiwi and
         | Chrome.
        
           | kgarten wrote:
           | It works for me, just needs a time to load.
        
             | aname2 wrote:
             | how long on what internet connection? i m on 1min and
             | counting on 50mbit. but maybe it doesnt work on ubuntu 24 +
             | firefox? should be webgl capable though.
             | 
             | ok took around 2min for me to load, then works.
        
               | Tade0 wrote:
               | Devtools say 40.23 MB / 13 MB transferred. Even on
               | 1000Mbps it needed a moment. Works for me on Ubuntu 24
               | and Firefox.
        
             | jampekka wrote:
             | Ah, thanks! Got it now on a better connection. A loading
             | indicator would ease confusion.
        
         | socalgal2 wrote:
         | I don't know if you designed it for a specific monitor but,
         | feedback. It tried using it on my M1 Mac.
         | 
         | First thing, there is no loading indicator and it takes too
         | long to start so I though it was broken a few times before I
         | realized I had to wait longer.
         | 
         | Second thing, although it was clearly tracking my head and
         | moving the camera it did not make me feel like I'm looking into
         | a window into a 3d scene behind the monitor.
         | 
         | These kinds of demos have been around before. I don't know why
         | some work better than others.
         | 
         | some others:
         | 
         | https://discourse.threejs.org/t/parallax-effect-using-face-t...
         | https://www.anxious-bored.com/blog/2018/2/25/theparallaxview...
        
           | svantana wrote:
           | Isn't it because the webcam FOV is unknown, which is needed
           | to estimate distance from pixel (along with face size, but
           | that should be less variant). The three.js demo had the
           | strength parameter that can be used to calibrate. The iphone
           | app is pre-calibrated for the most common devices, I believe.
        
         | president_zippy wrote:
         | It was definitely useful and appreciated on the "New" Nintendo
         | 3DS XL, which also used a camera to track your eye movements
         | and adjust the divergence accordingly. I hate the fact that
         | Nintendo abandoned this technology because experiencing Ocarina
         | of Time and Star Fox 64 in 3D was world-changing to me.
         | 
         | I'd say I'm not the only one who misses this technology in
         | games, because a used New 3DS XL costs at least $200 on eBay
         | right now, which is more than what I paid new.
         | 
         | I always thought 3D would combine really nicely with a ray
         | traced graphics full of bright colors and reflections, similar
         | to all those ray tracing demos with dozens of glossy marbles.
        
           | AuryGlenz wrote:
           | Samsung recently released a monitor with similar technology,
           | I believe, as a FYI.
        
             | nxobject wrote:
             | I'm surprised there's still a market for non-VR consumer
             | 3D! I remember the post-Avatar rush of 3D-related products
             | that never quite panned out.
        
           | bigyabai wrote:
           | The technology is still alive and well in some genres,
           | particularly flight sims. One common free solution is to run
           | OpenTrack with the included neural net webcam tracker, which
           | plugs into TrackIR-enabled apps and works like a charm.
        
           | behringer wrote:
           | Vr has taken over this market. Get a vr headset you won't be
           | disappointed.
        
             | president_zippy wrote:
             | Other than DCS, Skyrim, and that one Star Wars game at Dave
             | and Buster's where you duel Darth Vader, I don't see a lot
             | that sings to me just yet. Granted, I could easily get
             | 2,000 hours out of DCS over the span of a decade just
             | flying every third and fourth generation fighter jet ever
             | made.
             | 
             | Maybe VR doesn't need that many games because the small
             | handful of good ones have so much depth and replay value. I
             | guess I just talked myself into a $700 VR kit and possibly
             | a $700 GPU upgrade, depending on whether or not my RTX 3060
             | is up to task.
        
           | Wowfunhappy wrote:
           | The 3DS is different, it's using a lenticular screen so your
           | eyes actually see different images! The eye tracking allows
           | it to work even if the position of your eyes changes (ie
           | because you moved your head).
           | 
           | Presumably developers could have combined this with parallax
           | head tracking for an even stronger effect when you move your
           | head (or the console), but as far as I know no one did.
        
         | LordHeini wrote:
         | The obvious use case would be to replace the clunky head
         | tracking systems which are often used in simulator games.
         | 
         | Systems like trackir, which require dedicated hardware.
        
           | dTal wrote:
           | You can do this today with OpenTrack:
           | https://github.com/opentrack/opentrack
           | 
           | Also, TrackIR is just an IR webcam, IR leds, and a hat with
           | reflectors. You can DIY the exact same setup easily with
           | OpenTrack, but OpenTrack also has a neural net webcam-only
           | tracker which is, AFAIK, pretty much state of the art. At any
           | rate it works incredibly robustly.
           | 
           | Actually I have already used it to implement the same idea as
           | the post, with the added feature of anaglyph (red/blue)
           | glasses 3D. The way I did it, I put an entire lightfield into
           | a texture and rendered it with a shader. Then I just piped
           | the output of OpenTrack directly into the shader and Robert,
           | c'est votre proverbial oncle. The latency isn't quite up to
           | VR standard (the old term for this is "fishtank VR"), but
           | it's still quite convincing if you don't move your head too
           | fast.
        
           | jojobas wrote:
           | Trackir is just a camera with an infrared led.
        
           | trenchpilgrim wrote:
           | There's already a wide variety of Opentrack plugins that use
           | everything from off the shelf webcams to DIY infrared
           | trackers to an iPhone app and FaceID/AirPods.
        
         | Tade0 wrote:
         | I can confirm that is works decently well with a sunny roof
         | window in the background, which is normally enough for people
         | to complain that my face is too dark.
         | 
         | 8yo me, who instinctively tried to look behind the display's
         | field of view during intense gaming sessions, would appreciate
         | this feature very much. My belief is that if it shifted the pov
         | to a lesser degree than in the demo, people generally wouldn't
         | notice, but still subconsciously register this as a more
         | immersive experience.
         | 
         | I'm also glad that the web version doesn't try to cook my
         | laptop - good work.
        
         | utopcell wrote:
         | definitely laggy, but works even under low lighting conditions
         | and a camera that is not facing straight forward.
        
         | toss1 wrote:
         | Very cool!
         | 
         | I can see this quite useful for educational demonstrations of
         | physics situations and mechanical systems (complex gearing,
         | etc.). Also maybe for product simulations/demonstrations in the
         | design phase -- take output from CAD files and make a nice
         | little 3D demo.
         | 
         | Maybe have an "inertia(?)" setting that makes it keep turning
         | when you move far enough off center, as if you were continuing
         | to walk around it.
         | 
         | The single-viewer limitation seems obvious and fundamental, and
         | maybe a bit problematic for the above use cases, such as when
         | showing something to a small group of people. One key may be to
         | take steps to ensure it robustly locks onto and follows only
         | one face/set of eyes. It would be jarring to have it locking
         | onto different faces as conditions or positions subtly change.
        
         | nine_k wrote:
         | This is fun! But I see it showing me a close-up view (smaller
         | FOV) if I move my head back, and a wider view (larger FOV) if I
         | bring my head closer. This is the opposite to what I'd expect:
         | if I bring my head nearer to the screen, I should see a more
         | detail, closer (narrower FOV).
        
           | Wowfunhappy wrote:
           | Your expectation doesn't match real life! Try it with a
           | window. If you bring your head closer to the window, your FOV
           | increases, ie you can see more of the scene outside the
           | window.
        
         | marcodiego wrote:
         | How about contributing that to Godot?
        
       | aname2 wrote:
       | really fancy idea and cool project! Its a bit stuttery probably
       | due to the 30fps of a webcam but works. Feels slightly weird
       | somehow though, probably from the lag.
       | 
       | update: just tried to open the site again now and its gone but
       | leads to some kind of shop?
       | 
       | update2: oh use the link in the comment for the demo:
       | https://portality.io/dragoncourtyard/
        
       | brenschluss wrote:
       | BTW, the OG demo from Johnny Lee is from 2007:
       | https://www.youtube.com/watch?v=Jd3-eiid-Uw
        
         | poglet wrote:
         | Thanks for posting, I was sure I recalled something like this
         | form a long time ago. I also build my self a FreeTrack headset
         | (https://en.wikipedia.org/wiki/FreeTrack) around this same time
         | to play the Arma / Operating Flashpoint games using IR LED's
         | attached to a hat that my webcam would track.
        
         | xandman wrote:
         | Yeah, this came out during the last few weeks of my time in
         | high school. It is a major reason I got into computer science
         | and became a programmer. Good Times!
        
         | duckerduck wrote:
         | Wow, thanks for sharing, that really takes me back. I was so
         | hyped when I saw this as a kid, my dad and I made a mount for
         | my glasses with two IR LEDs and a battery. I remember that I
         | was super impressed with the effect.
        
           | AndrewOMartin wrote:
           | I also went to Maplins (UK Radioshack) and bought some infra
           | red LEDs to hack together something to achieve this same
           | effect. In the end I just taped the Wii Sensor Bar to my
           | glasses!
        
         | utopcell wrote:
         | That was a blast from the past! Many, including me, surely
         | still have those Wii sensors/controllers around. Fun times!
        
         | freethejazz wrote:
         | Came here to say the same. I remember playing around with this
         | back in the day, but using two candles instead of the sensor
         | bar. Yes, it works. No, it's not a good idea to hold candles
         | that close to your hair.
        
         | IshKebab wrote:
         | I tried implementing this with face detection-based head
         | tracking after that demo (or maybe before; I can't remember). I
         | got it working but the effect was very underwhelming. It looks
         | great in that video, but it kind of sucks in real life.
         | 
         | I think the problem is in real life you have an enormous number
         | of other visual cues that tell you that you're not really
         | seeing something 3D - focus, stereoscopy (not for me though
         | sadly), the fact that you know you're looking at the screen,
         | inevitable lag from cameras, etc.
         | 
         | I can't view the videos because of their stupid cookie screen,
         | but I wouldn't be too excited about this. The camera lag
         | especially probably impossible to solve.
        
           | stevage wrote:
           | Probably also the fact you just don't move much while sitting
           | in front of a screen, so the stereoscopy effect is much more
           | relevant.
        
         | ugh123 wrote:
         | This is all a severely underutilized technology
        
       | epaga wrote:
       | Interestingly, for this parallax 3D effect to work, the head
       | tracking needs to basically move "backwards" from typical head
       | tracking since it needs to keep the focal point the same, if I'm
       | understanding correctly. Any time I've tried this out it's fun
       | and would likely be most useful for something like a 3D painting
       | you hang on your wall.
       | 
       | Related idea, but not the same, might be my iOS and Android app
       | that uses your phone's AR for head tracking and then sends that
       | data to your PC for smooth sim game head tracking.
       | https://smoothtrack.app
        
       | mrheosuper wrote:
       | Is this similar to sony spatial 3d display ?
        
       | rspoerri wrote:
       | From my experience this only ever looks good in a recorded video.
       | Because we are used to assume that the real object captured
       | within the video is perceivable in a stereoscopic form. But it's
       | not. The real usage of head and viewtracking is as a controller,
       | not to improve immersion.
        
       | rullelito wrote:
       | Drawback is that it only works if you constantly move your head
       | or device.
        
       | quitit wrote:
       | Reminds me of the Amazon Fire phone which featured similar tech
       | prominently. "Dynamic perspective".
       | 
       | https://www.youtube.com/watch?v=6trOg2IK2Zg
        
         | hex4def6 wrote:
         | Tangentially involved in that project.
         | 
         | One of the big issues with that phone was that in order to do
         | dynamic perspective, you're having to run a 3D render at 60fps
         | constantly. That's a huge power hog, and prevents you from
         | doing many of the power savings techniques you otherwise could
         | on a normal phone -- shutting down the GPU, reduced refresh
         | rate, heck, even RAM backed displays.
        
       | richrichardsson wrote:
       | > This content is hosted by a third party provider that does not
       | allow video views without acceptance of Targeting Cookies. Please
       | set your cookie preferences for Targeting Cookies to yes if you
       | wish to view videos from these providers.
       | 
       | OK, that's a no then.
        
         | boredpudding wrote:
         | It's YouTube. This is super common, just worded in a weird way.
        
           | kimsey0 wrote:
           | It's also incorrect. They could just use youtube-nocookie.com
           | instead if tracking cookies are disabled. https://support.goo
           | gle.com/youtube/answer/171780?hl=en#zippy...
        
       | stavros wrote:
       | Does this really fool you if you have two eyes? I haven't been
       | able to try it or watch the videos (they're behind a cookie
       | warning I can't get past).
        
         | spwa4 wrote:
         | If the latency is low enough to fool you, it makes the screen
         | look like a window. It's much more limited than a headset, but
         | especially with a natural scene, it does get the illusion
         | across.
         | 
         | But you're still behind the window.
        
       | papes_ wrote:
       | I remember this being done for a DSIware game released ~2010 - I
       | couldn't find much footage apart from this quick clip from a
       | trailer.
       | 
       | https://youtu.be/4zZfsyHEcZA?si=BE2I991zEVxPEt9F&t=57
       | 
       | Seemed to have some different names depending on region
       | (Looksley's Line Up, Tales in a Box: Hidden Shapes in
       | Perspective). I recall it working very well at the time.
        
       | guyromm wrote:
       | here's a webgl poc that was tested with mobile & desktop
       | browsers:
       | https://www.webgma.co.il/Articles/window-3d-tracking/en/
       | 
       | source code at https://github.com/guyromm/Window
       | 
       | imho this should be useful for driving/flight sims, giving the
       | player the ability to lean inside the vehicle, changing their
       | viewpoint on the surroundings.
        
       | nunodonato wrote:
       | How is this different from the many available head tracking
       | devices? I used to play Flight Simulator with head tracking[1].
       | It was great, although it did consume a bit of CPU cycles. IR
       | trackers are more efficient
       | 
       | [1] - https://www.youtube.com/watch?v=P07nIcczles (actually, this
       | one was using a paper tracker because the face tracker had a big
       | impact on fps)
        
       | Mountain_Skies wrote:
       | Seem to recall one of the pinball emulators having this as a
       | plug-in years ago.
        
       | SirMaster wrote:
       | But does it actually make stuff look like you can reach out and
       | touch it like the 3D movies at theme parks? I don't see how it
       | would. This just seems like parallax.
       | 
       | You can do this with a Kinect for head tracking and people do
       | that with homemade pinball machines using a TV as the table, and
       | a Kinect to track your head, so it looks like the table is 3D
       | down into the TV.
       | 
       | But I don't think it creates the full 3D effect with things
       | looking like they are coming way out of the screen and like a
       | tangible thing you can reach out and touch.
        
       | Ninjinka wrote:
       | Calling this 3D is a stretch, it does not make things appear like
       | they're coming out of the screen. That requires having a way to
       | show something different to each eye, something not possible with
       | a standard display.
       | 
       | I did see a demo of 3D without glasses on a full monitor that DID
       | make it look like it was coming out of the screen at CES, it
       | requires a $3000 monitor though:
       | https://www.3dgamemarket.net/content/32-4k-glasses-free-3d-g...
       | 
       | Also the 3DS obviously.
        
         | regularfry wrote:
         | Not strictly true. Out past a certain distance your brain uses
         | parallax for depth cues because the difference between each of
         | the eye's images is too small. It's 3d, just not stereoscopic
         | 3d.
        
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