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4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

marctenbosch.com

21–30 of 101 posts

Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#21

I am genuinely surprised for a long time that I've not seen 4D monsters in films. It has been so obvious to me there's potential there. It would of course be a flat 2D projection of a 3D slice through a 4D creature, so it would look like a smoothly morphing between different creatures, and in and out of existence so we've sort of had morphing for a long while (since Willow, C. 1985) but... there's potential. In case…

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Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#22
post #17

This would make for a really fun video game. Think about a 4D shooter in the vein of Portal. I imagine that after awhile the human brain would learn to recognize patterns in 4D spatial reasoning.

I've been working towards making something like a 4D Descent, but I keep getting sidetracked by problems like 4D physics, collision detection, and mainly how to model interesting 4D objects.

What Marc's done with Miegakure, from what's publicly visible, is pretty incredible. I have no idea how he's managed to seemingly create a coherent 4D world while only being able to view a slice of it at a time. I guess it's a bit like using ed instead of a modern text editor.

Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#23
post #9

I'll ask any physicists out there. A 4th spatial dimension probably doesn't exist, right? Even if we couldn't perceive shapes across a 4th dimension, we would still perceive things moving through the 4th dimension like we see in 4D toys. In reality we don't ever see anything like this (spatially anyway). Is that correct?

A classical particle (think a pebble) exists in 6 dimensions, 3 positions and 3 momenta.

Nothing (in the classical, non-quantum) setting is solely determined by position coordinates.

Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#24

I would like to see the 4th dimension projected into 3d and not just a slide, same as you could project the 3d into 2d, by showing further objects smaller and closer objects bigger.

You can absolutely do this (and it would be quite interesting to try with a VR headset, e.g.!); the idea is a special case of the projective transform [0] in 4 dimensions. It may make for a cool demo.

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[0] https://en.wikipedia.org/wiki/Homography

Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#25
post #9

I'll ask any physicists out there. A 4th spatial dimension probably doesn't exist, right? Even if we couldn't perceive shapes across a 4th dimension, we would still perceive things moving through the 4th dimension like we see in 4D toys. In reality we don't ever see anything like this (spatially anyway). Is that correct?

A classical particle (think a pebble) exists in 6 dimensions, 3 positions and 3 momenta. Nothing (in the classical, non-quantum) setting is solely determined by position coordinates.

I forgot most of the details already but as far as I remember, some classes of splines are 4 dimensional constructs that are then projected to 3 dimension to get your 3d spline curve.

Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#27

I am genuinely surprised for a long time that I've not seen 4D monsters in films. It has been so obvious to me there's potential there. It would of course be a flat 2D projection of a 3D slice through a 4D creature, so it would look like a smoothly morphing between different creatures, and in and out of existence so we've sort of had morphing for a long while (since Willow, C. 1985) but... there's potential. In case…

Futurama had a 4-D "space" white whale in the Bermuda Tetrahedron in S6 E21 "Mobius Dick".

Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#29
SIGGRAPH 2020 in July is all online because Washington DC is keeping their convention center as a makeshift hospital through the summer. I have not seen revised registration fees for this conference yet and hope they are reduced. I attend approximately every other year and its on the pricey side.

Re: 4D Toys: how objects bounce and roll in 4D – paper accepted to SIGGRAPH 2020

#30

Wow, the title does not make it justice: I only went to look at it in an idle moment after lunch. Much better to transcribe the beginning of the video: 4D Toys is a toy box filled with 4-dimensional toys. By 4-dimensional I mean that they exist in a world with 4 dimensions of space and 1 dimension of time, instead of 3 dimensions of space and 1 dimension of time. It turns out that the rules of how objects bounce, sli…

Ok, let's take the title from the video instead. Thanks for pointing this out! Sometimes the best work hides behind dry or modest language.

It's easy enough, albeit annoying, to brush away the inflated mediocre. It's so much harder to locate the unseen gems.

Edit: ah, I see - the video is from 2017, and there was a thread back then too: https://news.ycombinator.com/item?id=14471931. I guess we'll make an ugly hybrid of the titles.

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