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Show HN: Test your shape rotation skills

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Re: Show HN: Test your shape rotation skills

#161

Post by whatshisface »

crdrost wrote: post #147
whatshisface wrote: post #12

Sometimes the initial rotation hides a part of the shape. Also, I have always wondered if there's a way to translate these shapes to strings for quick "mental algorithm" matching. Something like, "5, left turn, 3, right turn..." I guess you'd need a normal form. The first turn can be defined as always "right" or "left," and subsequent turns can be right, left, up or down. The first turn that's "up" or "down," can be…

> The first turn can be defined as always "right" or "left," No it can’t, not in 3D... it is just a turn. You can however choose to rotate about the first segment until the turn is Right, then use this orientation for the rest. In terms of normal form and restarts, who cares? Just generate the string both ways, it’s 2n computations, choose the lowest in lexicographic order, and life is good. If you get to billions of…

Right-handed rotation is different from left-handed rotation no matter what coordinate system you choose.

Re: Show HN: Test your shape rotation skills

#163

Post by jimmySixDOF »

For VR (Quest/Steam) There is a beautiful minimalistic game called Cubism that uses a similar set of shapes in 3 dimensional space where you need to fit the group of blocks into increasingly complex forms. It's a very soothing environment and the graphics are so clear with technical touches like a high frame rate (120hz), perfect hand controls, and use of AR/passthrough, all possible due to the relatively simple game requirements. Highly recommend the experience if you can do it.

There is also a free open version similar to Cubism built in WebXR called Plockle that follows the same theme [2].

[1] https://www.cubism-vr.com/

[2] https://constructarcade.com/game/plockle/

Re: Show HN: Test your shape rotation skills

#164

Post by emschlr »

crdrost wrote: post #147
whatshisface wrote: post #12

Sometimes the initial rotation hides a part of the shape. Also, I have always wondered if there's a way to translate these shapes to strings for quick "mental algorithm" matching. Something like, "5, left turn, 3, right turn..." I guess you'd need a normal form. The first turn can be defined as always "right" or "left," and subsequent turns can be right, left, up or down. The first turn that's "up" or "down," can be…

> The first turn can be defined as always "right" or "left," No it can’t, not in 3D... it is just a turn. You can however choose to rotate about the first segment until the turn is Right, then use this orientation for the rest. In terms of normal form and restarts, who cares? Just generate the string both ways, it’s 2n computations, choose the lowest in lexicographic order, and life is good. If you get to billions of…

The keyword is "define"!

You can just define the first turn to be Right no matter how it is oriented.

If you are not happy with that then just rotate the first segment until it looks Right to you. Then label the other turns.

If you are still not happy with the word Right to denote the first term then just make up new notation. Define the first turn to be 1. Use numbers to denote turns if you object to using Left and Right.

Re: Show HN: Test your shape rotation skills

#165

Post by emschlr »

_3u10 wrote: post #132
barrkel wrote: post #113

IMO this would be more enjoyable if the shapes were more different morphologically, and fewer (ideally no) close pairs which differ only in the length of a segment by a single block. After the first couple of wrong guesses (though I'm pretty sure one guess was correct - could be the bug https://news.ycombinator.com/item?id=30408567 ) I started to count segment lengths rather than relying on mental shape rotation.

Using less strength in your solving algo is a peak shape rotator skill. It’s yet another kobyashi Maru incident.

IIRC Kobyashi maru incident involves a no-win situation where you change the rules of the game to create a winning situation. How are we looking at a Kobyashi maru incident here? Can you explain?

Re: Show HN: Test your shape rotation skills

#166

Post by djtango »

whatshisface wrote: post #12

Sometimes the initial rotation hides a part of the shape. Also, I have always wondered if there's a way to translate these shapes to strings for quick "mental algorithm" matching. Something like, "5, left turn, 3, right turn..." I guess you'd need a normal form. The first turn can be defined as always "right" or "left," and subsequent turns can be right, left, up or down. The first turn that's "up" or "down," can be…

>Also, I have always wondered if there's a way to translate these shapes to strings for quick "mental algorithm" matching. Something like, "5, left turn, 3, right turn..."

I was once measured to have abysmal spatial reasoning (which is probably backed up by poor hand-eye coordination and sense of direction) but I had no problem doing molecular geometry and group theory, I suspect it was because I applied logic rather than visualisation to compensate. (I am terrible at walking into an empty place an imagining how I might want to fill it)

Re: Show HN: Test your shape rotation skills

#169

Post by makach »

9 on my first try. Spent ages on the first one to figure out what was going on. I guess, reading from the comments, that it is possible to get real good at recognizing these patterns and with practice you can reach the upper limit of how fast you can click and match the objects.
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