Interactive 4D world!

[quickfur]

I finally got around to trying out John McIntosh's 4D Blocks game, and I have to say, I'm awestruck.

This game begins with a 4D maze to acquiant you with the movement controls, and then you can load in other world description files that lets you explore 4D (and 3D) worlds in first-person perspective. You can pick up blocks, move them around, and use them to build larger structures, and there's even a cute little animated train that moves around preset tracks, that you can try to follow around in 4D to see how good your 4D tracking skills are. The game comes with 400 different scene files that you can load, and includes all sorts of scenarios, from mazes to city blocks to train loops, there's even a couple of files that lets you play with a 120-cell in-world (i.e., as a real 4D object that you can pick up and move around, or look at from different angles -- not just an isolated object but part of a larger world). Really amazing!!

It does take a while to get used to the movement controls and the perspective projection 4D view, and the graphics may look primitive at first glance, but don't be fooled! Once you get used to it, you feel like you're really living in a 4D world! Very highly recommended way to explore a truly 4D world! It will truly test your ability to visualize 4D and develop a real geometric intuition for 4D space. I cannot recommend this game enough! Stop reading this and go download and play it already!

[anderscolingustafson]

I downloaded it and I was about to open one of the files in it and my computer asked me which program I wanted to use to open it.

A Picture of my screen.jpg

(143.31 KiB) Not downloaded yet

Which program should I use to open the file?

[Keiji]

It looks like you can't just open the files directly.

According to the instructions here, the following should work:

1. unzip all files to a folder
2. go into the "out" folder
3. shift-right click on any blank space (ie not on a file), then choose "Open command window here"
4. type "java Maze" and hit enter

Also, to take a screenshot pre-Windows 8, press Print Screen, open Paint, paste, crop, and save. (Please would people stop taking photographs of their screens...)

[gonegahgah]

I've played it briefly quickfur but I must admit I haven't go a clue what is happening.
I'll have to keep playing with it and hope it makes sense to me.

I am still hoping a more immersive game can eventually be made for everybody using the rotational projection that I found while on this blog.
I've played a demo of a game called The Talos Principle. It's a 3D game but it has beautiful visuals.
I was thinking while I was playing it how beautiful it would be to see it in 4D via "rotational projection".

I've imagined a 2D->3D scenario to help paint a better picture of rotational projection.
If we have a 3D piece of paper (or sign post) and you want to have a 2Der read it than how do they do that?
It is most probable that a 2Der would write in some sort of morse type of lettering.
Maybe they would have short and long dashes as well as the dots and normal dashes to create more combinations of letters.

If we want to send a message to the 2Der we will have to put a series of these dots and dashes down our 3D page.
We might even give these dots and dashes extra width so that 2Der doesn't just turn or slide straight passed them when skipping into other frames of our dimension.

But what from a distance tells the 2Der that they are looking at the 'front' of our page that we have put the writing on?
To the 2Der our page looks like a vertical line from any angle.

This is where rotational projection can help. Rotational projection means that the 'sideways' aspects of the page are ghosted and translated vertically by rotation.
If they are looking at the page edge on (as we see it) then it doesn't have a left or right. In that case they will see no ghosting vertically.
When they get themselves into a position where the page is in 'front' of them - as we see the page is in 'front' of us - then the page does have a left and right.
These left and rights are ghosted and translated vertically by rotation.

So the 2Der sees a ghost image of the page above and below the part of the page they can presently see.
Depending upon where they are looking at the page will determine how much ghosting is below and how much is above.
The more they looking towards the 'left' of the page the more ghosting there will be above and vice-versa more ghosting below when they are looking towards the right of the page.
This technique allows them to align up on a page as we would see it.
Even looking at the page from different places has an effect. If you are looking at it not quite straight on the ghosting will be shorter above + below.

The same thing could be done for 4D objects projected into our 3D space. Ghosting would allow us to align up with 4D objects to say read a message from the 4Der to us.
They would have to do a similar thing and write our letters on their 4D page. Again they would have to make them a little wider so we don't turn straight passed the letters.
Again, like for the 2Der, if we are looking at the edge of the 4Der's page we won't see any ghosting above even if it looks like we are looking at a flat sheet.
It's not until we have that ghosting appear above and below that we can hope to scan across the front of the 4D-page.

What we will see when we scan across the 4D-page is primarily a blank page most of the way; just like the 2Der would see with ours.
Suddenly writing will appear on the page and will just as quickly disappear if we scan too far.
Because the 4D has made the letters 4D-wider in a 4D sense then we should have more luck to find the letters.

So just as we had to think about how the 2Der can only see a line at a time of our page; the 4Der has had to think about how we can only see a rectangle at a time of their page.

Rotational projection and ghosting should allow you to keep all the objects and their extents in view while allowing you to align up with them in more useful ways...
Why rotation. This draws on the finding that 4D sideways is 360° and not just left and right like we have in 3D.
Our 3D vertical also has 360° providing us with a perfect place to ghost project into via the rotated projection; just as the 2Der could do to try to depict our universe.
This means we don't have to worry about where to project all the objects to; which is the main problem with ana-kata projection.
Every 4D point has a point to plot to, with rotated projection, in a way that I feel will be much easier to visualise and interact with...

The proof would be in the product of course and I hope to be able to see this brought to reality one day.

[gonegahgah]

The texture maps would be a challenge. They would have to be a cube array of dots instead of square array of dots.
Or even a omnitruncated tetrahedron. So that the dots are more closely arranged for different angles. Or maybe you need 4 alignments to get best orientation maps.
Lot of extra data, anyway! Maybe procedural maps would be less data but less detailed?
Would be interesting to see...