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I realized chess pieces can be redesigned to be geometric attack directions

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Re: I realized chess pieces can be redesigned to be geometric attack directions

#112

Earlier quoted context omitted.

Most people think of the knight move as one straight and then one diagonal. However, this is still ambiguous. Imagine one up, then one down left for example, resulting in the square left to the original square. A better description is moving 2 squares straight, not diagonal, into one direction, then moving 1 square into a 90° turned direction.

Most people think of the knight moving 2 and then 1.

Chess players do, yet experience of basically any non-player I have ever heard describing it as "one straight, one diagonal" tells me otherwise. Also "moving two and then one" is ambiguous and would allow moving 3 squares into the same direction.

Re: I realized chess pieces can be redesigned to be geometric attack directions

#113
post #110

Earlier quoted context omitted.

I also realized that if you defined the pieces like their moves, the knight's shape would be.... Interesting

Wouldn’t it look like four capital tees joined at opposites/right angles at the stem?

I mean, sorta? If you think about it as the "rules of the move," but the actual movement can be drawn as a straight line. See: https://twitter.com/graycrawford/status/1750248031784763639

Re: I realized chess pieces can be redesigned to be geometric attack directions

#114

For me the most surprising observation from this thread is this tweet [1] showing that the knight's moves are exactly the squares that the queen can't get to within a 2 square manhattan distance. I.e. the knight is an anti-queen. [1]: https://twitter.com/skidbladnirr_/status/1750285122769957129

You mean a 2-square Chebyshev distance, I think (the Linf norm). A 2-square Manhattan distance (the L1 norm) wouldn't include any of the squares that a knight can get to.

[deleted]

Re: I realized chess pieces can be redesigned to be geometric attack directions

#115

For me the most surprising observation from this thread is this tweet [1] showing that the knight's moves are exactly the squares that the queen can't get to within a 2 square manhattan distance. I.e. the knight is an anti-queen. [1]: https://twitter.com/skidbladnirr_/status/1750285122769957129

You mean a 2-square Chebyshev distance, I think (the Linf norm). A 2-square Manhattan distance (the L1 norm) wouldn't include any of the squares that a knight can get to.

For those that want a visual description there's a blog I serendipitous recently ran into[0]. If you're too lazy to open:

- n-square Chebyshev distance forms concentric squares around your starting point

- n-square Manhattan Distance forms diamonds (meaning up/down/left/right = 1 space away but all diagonals are 2 spaces away)

We could also say the Knight can go everywhere a queen can't in the 3-square Manhattan distance and this might be more useful since it is all points along that boundary except the corners! (We got an in the wild "2 problems in computer science" with an "off by 1" error :)

[0] https://chris3606.github.io/GoRogue/articles/grid_components...

Re: I realized chess pieces can be redesigned to be geometric attack directions

#116
post #79

Earlier quoted context omitted.

In Chinese chess, the horse behaves like the knight in western chess except that (a) it cannot jump over pieces, and (b) the definition of jumping over is that it first move horizontally/vertically 1 step and then diagonally 1 step. It cannot first move diagonally. This also leads to situations where two knights can be positioned amongst other pieces such that one knight is able to capture the other but not vice vers…

Most people think of the knight move as one straight and then one diagonal. However, this is still ambiguous. Imagine one up, then one down left for example, resulting in the square left to the original square. A better description is moving 2 squares straight, not diagonal, into one direction, then moving 1 square into a 90° turned direction.

But in Chinese chess, if the knight can't pass other pieces, thinking of it that way would be a rule change.

Re: I realized chess pieces can be redesigned to be geometric attack directions

#117
post #8

That is very clever! But I hate the way the pawns face. Makes sense! But it still reads, to me, like one of those "color, but the text is in a different color" things. Feels like the pawns should be facing the opposite direction. =/

Yeah, I wonder if it would be a slight improvement to combine move+capture. So pawns would be /|\ /|\ \|/ \|/ which looks less anti-directional.

It would make sense to have move and capture be different. Like square in front and two lines or points to the diagonal.

Re: I realized chess pieces can be redesigned to be geometric attack directions

#118
post #52

I think this is fun, but (a) knights' threats are disconnected and this "flower" approach while good is maybe not ideal. You might as well use a hollow circle at that point. (b) when we say "chess pieces can be redesigned to be..." then I think about actual physical pieces, it would not do to make these as actual physical pieces because an accidental misplacement turns a rook into a bishop or vice versa. Gotta make t…

I think I'd be inclined to disambiguate them by making the ends of the bishop pointed and the ends of the rook blunt. When moving along a diagonal you're moving in the direction of square corners, vs faces for moving in ranks and files, so it makes sense in that way, and it also evokes the shapes of the classical pieces.

Re: I realized chess pieces can be redesigned to be geometric attack directions

#120
post #52

I think this is fun, but (a) knights' threats are disconnected and this "flower" approach while good is maybe not ideal. You might as well use a hollow circle at that point. (b) when we say "chess pieces can be redesigned to be..." then I think about actual physical pieces, it would not do to make these as actual physical pieces because an accidental misplacement turns a rook into a bishop or vice versa. Gotta make t…

A swastika shape would make sense for the knight.

I guess there is still a cultural aversion to its use, however.

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