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.
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!
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.
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.
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.
