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How to walk through walls using the 4th dimension [video]

marctenbosch.com

31–40 of 99 posts

Re: How to walk through walls using the 4th dimension [video]

#31
post #15

Earlier quoted context omitted.

Unless 3d space is 'wrinkled'; in 4D you could travel straight there. Imagine a crumpled sheet - the 2D traveler would have to trace a route through all the convolutions to reach the other end of the sheet. The 3D traveler may only have inches to go. 'A Wrinkle in Time' was a story about this.

You'd just have to hope that the place you want to go to is wrinkled up so that it's next to you, and not still far away.

Actually going anyplace at all that way would be hugely exciting.

Re: How to walk through walls using the 4th dimension [video]

#32

I was really hoping for a continuous (rather than discrete) fourth dimension. The concept is cool and looks to be well executed, but it's not very different from other alternate reality implementations such as the Dark World in Legend of Zelda.

Isn't that addressed in the additional notes below the video?

    There are **infinitely** many 3D worlds stacked on top of 
    each other, even if in the Wall level the ground texture 
    makes it seem like there are only two.

Re: How to walk through walls using the 4th dimension [video]

#34
post #6
post #5

Earlier quoted context omitted.

Some rubble fell to the side, along the 4th axis. This is a 4th spatial dimension, not time.

But the fourth dimension is timespace, is it not? At least that was what I gathered from Special and General Relativity and the relativity of simultaneity. X^t, Y^t, Z^t?

In a lot of cases, the fourth dimension is describe as space. But if you were looking into string theory, often times there are description of many spatial dimensions, say 11 spatial dimensions and then a single dimension of time.

We could also have multi-dimension time dimensions as well. The idea of parallel universes where at least one decision is made differently from our own could instead be different dimensions of time. Move to the left or right in time and experience different choices as opposed to only going forward as I assume most of us do now. :D

Re: How to walk through walls using the 4th dimension [video]

#35
I've been getting progressively more excited about Miegakure over the past year, but I haven't heard anyone who's played the game talk about how easy it is to "grok". Does moving between dimensions become intuitive over time? Or do you always have to consciously think about what you're doing?

Re: How to walk through walls using the 4th dimension [video]

#36
post #33

If this topic interests you, you should definitely check "Imagining the Tenth Dimension" https://www.youtube.com/watch?v=zqeqW3g8N2Q

That video is incoherent nonsense, especially from the '5th dimension' and onwards, and in no way resembles the modern understanding of dimensions in physics or mathematics. I wouldn't bother watching it except for entertainment.

Re: How to walk through walls using the 4th dimension [video]

#37

The game looks fascinating. I'm still trying to get my had around the analogies, but get the feeling that playing the game for real will bring a level of intuition to the experience. In the meanwhile, can anyone help me out? In the 2D->3D example, you have one shared axis (Z -- vertical), and an alternating pair for the second axis (X and Y -- horizontal). In effect, from the 2D character's point of view, 'jumping' i…

This is exactly right: when rotating in 4D, you can rotate "around" a plane, leaving it in place. You can also rotate around a line (permuting the other three axes).

So, in the video. The Z axis doesn't change (up and down) so that's one axis. The other one that doesn't change is at a 45 degree angle from lower left to upper right. Watch the tree: it is just as wide along this axis as it was before. Everything else sort of smoooshes around but that plane stays the same.

I suggest interested people check out adanaxis, a 4D space shooter. It's not particularly playable, but it is true four-dimensional space with four-dimensional spaceships zipping around.

Re: How to walk through walls using the 4th dimension [video]

#38
post #6
post #5

Earlier quoted context omitted.

Some rubble fell to the side, along the 4th axis. This is a 4th spatial dimension, not time.

But the fourth dimension is timespace, is it not? At least that was what I gathered from Special and General Relativity and the relativity of simultaneity. X^t, Y^t, Z^t?

I don't think dimensions are specifically numbered. You could call up one dimension, distance along a fixed track another dimension, and distance from the sun your third dimension. You could call temperature your fourth dimension and mass your fifth. This game specifically has 4 spatial dimensions.

Re: How to walk through walls using the 4th dimension [video]

#39
Its really awesome, but its a portal game where you play between two maps. It's not "4D" in any real geometric sense.

4D objects projected into 3D space would be warped in "the same way" that a map is warped projecting the globe onto a plane. 4D objects would be warped projecting into 3D which would then be warped as it was projected into 2D.

It would be worse than the way that Iceland looks bigger than North America on some maps.

This is really inventive game play, so I'm not slagging it off. I'm just saying that the "4D" explanation is more of a metaphor than a real geometric projection.

Re: How to walk through walls using the 4th dimension [video]

#40

Earlier quoted context omitted.

That would be really cool. The mathematics involved don't seem too difficult; you have to add another axis to your vectors, points, and transform matrices, and you can place and orient your models in 4D space, set up lights and a camera in 4D space, and project the camera's view into 3D space first then onto the 2D display. I think the hard part is creating the models and writing the rendering engine. Creating 4D mod…

This is something I've been working on as a side-project on and off for a while. It's complicated by the fact that every existing engine is built around the assumption that you only want to use 3 dimensions, not four, and not arbitrarily many, so I've been pretty much writing everything from scratch (and very limited GPU acceleration, as you said, because GPUs also assume 2 or 3D). So far, I'm punting on model buildi…

One possible way of getting around that, stolen from machine learning, is to use colors to represent the fourth dimension, ie, make things darker (or change the hue/saturation) that are bigger in the fourth axis, and vice versa for smaller.
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