
Design company made illusion of ocean waves trapped in architecture - glitcher
https://cdm.link/2020/05/anamorphic-architectural-illusion-seoul/
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hermitcrab
So does the illusion only work from some angles?

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goldenkey
Seems like it has to be the case since a screen can only show a single pixel
to observers from all angles - but we know that pixel is supposed to actually
correspond to the lightray from all those angles (the basis of raytracing.)
The depth is statically set - so it appears the lightray started out within
the chamber - and since the pixel is static - the angle of the observer also
has to be set. Luckily the distance is a variable that scales just fine as
long as the vanishing point is along the observers axis. And if I had to
guess..it's all pre-rendered ray tracing on loop. Particle effects this good
are near impossible to do real-time without some heavy duty equipment.

Still, super impressive coordination of the physical positions of the screens
and the effects, mapping from physical space to model space.

If I had to guess how it is done? Each screen has 2 position sensors or
transmitters (4 aren't necessary) in opposite corners. The simulation, when
first installed, is calibrated by pulling all those positions in, to build the
chamber model from the point position vertexes of the chamber screens. Then
the simulation is ran and recorded, using raytracing, projected to an observer
standing somewhere centered in front of the chamber. Generate a long enough
loop (15 minutes?) to be unnoticeable. This footage is saved and now the
screens just become dummy displays that just need to play a video file, that
can even be on an SD card. Synchronization can be an issue but that's as easy
as just using IR remote/trigger to start them all playing at the same time.

Maybe they've just done a lot more but I'm just providing the low maintenance
solution I would do if tasked with the project.

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pintxo
There is a linked article on how to start making anamorphic illusions:
[https://medium.com/@tqvinn/the-secret-to-anamorphic-
illusion...](https://medium.com/@tqvinn/the-secret-to-anamorphic-
illusions-853e3674209a)

