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Comment by barrkel | Hacker News Reader

The mirror on the wall of the bathroom in the Berlin location looks through to the kitchen in the next room. I guess the depth gauging algorithm uses parallax, and mirrors confuse it, seeming like windows. The kitchen has a blob of blurriness as the rear of the mirror intrudes into kitchen, but you can see through the blurriness to either room.

The effect is a bit spooky. I felt like a ghost going through walls.

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The refigerator in the NYC scene has a very slick specular lighting effect based on the angle you're viewing it from, and if you go "into" the fridge you can see it's actually generating a whole 3d scene with blurry grey and white colors that turn out to precisely mimic the effects of the light from the windows bouncing off the metal, and you can look "out" from the fridge into the rest of the room. Same as the full-length mirror in the bedroom in the same scene—there's a whole virtual "mirror room" that's been built out behind the mirror to give the illusion of depth as you look through it. Very cool and unique consequence of the technology

Wow, thanks for the tip. Fridge reflection world is so cool. Feels like something David Lynch might dream up.

A girl is eating her morning cereal. Suddenly she looks apprehensively at the fridge. Camera dollies towards the appliance and seamlessly penetrates the reflective surface, revealing a deep hidden space that exactly matches the reflection. At the dark end of the tunnel, something stirs... A wildly grinning man takes a step forward and screams.

Would you be offended if I animated that scene? It is really well described?

Please share if you do, that sounded spooky af

Please feel free!

Neat! Here are some screenshots of the same phenomenon with the TV in Berlin: https://imgur.com/a/3zAA5K8

Oh wow yeah. It's interesting because when I look at the fridge my eye maps that to "this is a reflective surface", which makes sense because that's true in the source images, but then it's actually rendered as a cavity with appropriate features rendered in 3D space. What's a strange feeling is to enter the fridge and then turn around! I just watched Hbomberguy's Patreon-only video on the video game Myst, and in Myst the characters are trapped in books. If you choose the wrong path at the end of the game you get trapped in a book, and the view you get trapped in a book looks very similar to the view from inside the NYC fridge!

Mirror worlds are a pretty common effect you'll see in NeRFs. Otherwise you would need a significantly more complex view dependent feature rendered onto a flat surface.

This happens with any 3D reconstruction. It's because any mirror is indistinguishable from a window into a mirrored room. The tricky thing is if there's actually a something behind the mirror as well.

Yes!

The barely-there reflection on the Berlin TV is also a trip to enter, and observe the room from.

What does the reconstructed space look like when there are opposing mirrors? It’ll just be a long corridor of ever more blurry rooms?

Funnily enough, this is how reflections are usually emulated in game engines that do not support raytracing: another copy of the world behind the mirror. Also used in films in a few places (e.g. Terminator)

Please look at the refrigerator I mentioned—it's definitely not the classic "mirror world" reflection that you'd normally see in video games. I'm talking about the specular / metallic highlights on the fridge being simulated entirely with depth features.

You can also get inside the bookcase for the ultimate Matthew McConaughey experience.

Try noclipping through the TV in the Berlin living room. It gets pleasantly creepy.

It has exactly the same drawbacks as photogrammetry in regards of highly reflective surfaces.

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