Seattle Chess Resource
Northwest Chess: Chess News from Washington and Oregon. My chess playing appears to greatly suffer during Winter, perhaps related to the general lack of sunlight? Also very blunder prone when on-call…
May 08, 2008
November 08, 2007
Shogi SFEN
MacShogi offers no feature to edit the board, which makes position reproduction difficult. A web search revealed a FEN-like format for Shogi (SFEN hereafter), a great improvement over images or even text diagrams. Consider the following example. (For those unversed in Shogi, the Kings usually do not end up this close, which is mostly a testament to my poor 詰 [つめ: tsume] skills (the opposing King fled from a decimated Mino-Gakoi castle).)
Gote (w): 3P L N R 9 8 7 6 5 4 3 2 1 ---------------------------------------------- | Lw | Nw | Sw | | | | | | Lw | a ---------------------------------------------- | | Gb | | | | | | | | b ---------------------------------------------- | | Pw | Pw | Pw | Pw | | | | | c ---------------------------------------------- | Pw | | | | | Rb | | | Pw | d ---------------------------------------------- | | | Bb | Pb | | | | Pw | | e ---------------------------------------------- | Pb | Sb | | | | | | Pb | Pb | f ---------------------------------------------- | | Kw | Sb | | Pb |+Pw | | | | g ---------------------------------------------- | | Gb | | Gb | | | | | | h ---------------------------------------------- | Lb | Nb | | Kb | | | | Nb |+Bw | i ---------------------------------------------- Sente (b): 2P S G
Using Shogi SFEN, the position above would become:
lns5l/1G7/1pppp4/p4R2p/2BP3p1/PS5PP/1kS1P+p3/1G1G5/LN1K3N+b w GS2Prnl3p 1
A SFEN to board display conversion program would help display games, plus parsers to convert ASCII diagrams into SFEN. There exist Japanese sites that allow game replay, though these are all in Japanese. Time to start learning a new language or two…
In contrast, Java Shogi Board uses the FEN notation [FEN "1nn6/2S+P1+L1P1/kgs4+R1/1lpP2pp1/KP2Sp3/l1P3P1p/+b1N1SP3/4G3R/3G3N1 200011 0/4000000 s 55"]. I dislike this format, as the pieces in hand are not clear from the magic numbers.
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October 01, 2007
Chess Checkmate Patterns
If the opposing King can be trapped behind a pawn wall, this leads to back rank and similar mates. Your own King can be used instead of the pawn wall, in a King and Queen versus King endgame. Trapped by Rook mate:
Two Rooks or a Rook and a Queen can deliver a “stripe” pattern checkmate, where the King walked to the edge then trapped as above. This may not work or will require Rook adjustment if the King as able to attack a Rook via a diagonal. White to move (mate in two):
Unique to the Queen, trapping the King against the side of the board. The Queen requires support from something else:
Also, the Queen both attacks and supports other pieces:
I find open position mates the hardest to “see”, though these can bring a quick end to the game. An easy pattern boxes the King between your King and (supported!) Queen:
The Queen covers the horizontal, vertical, and diagonal, which leaves only two open squares for a Bishop or Knight to close. This assumes the King cannot flee from the Queen; a Rook, the board, or your King must complete the box. White to move and mate in one:
Other checkmate can be delivered where other pieces (often those belonging to the opponent) box in the King. This requires more material, should one lack a Queen. If (and only if) the opponent can move other pieces, placing the King into stalemate is a safe option, as a subsequent check usually yields checkmate. Many mate-in-2(or more) puzzles require stalemating or moving the King into a specific mate pattern. However! Crafty opponents may find ways to force stalemate, especially via sacrifices that then rob them of legal moves. For example, White has just promoted via c8=Q, and threatens mate with a supported Queen pattern. Black to move:
Note: the smothered Mate was shown in a previous entry. This method uses a Knight to deliver mate against a King trapped by his own army (and the sides of the board).
September 11, 2007
Chess Pins
Chess has two types of pins, absolute when a piece is pinned to the King, and soft (or relative) when a piece is pinned to something of higher value, such as a Queen or Rook behind a Knight. Soft pins can be broken. On the previous move, Black moved Bg4, creating a pin on the Knight and Queen. White to move:
FEN rn1qkb1r/pp2pppp/2p2n2/8/2B3b1/2N2N2/PPPP1PPP/R1BQ1RK1 w kq - 2 7
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September 02, 2007
Windmill Attack
Windmill attacks are rare in chess, though once the opposing King is trapped into a check-revealcheck-check cycle, much damage can be inflicted. White to move.
FEN 2kr3r/1pp3pp/4p3/Bb2p3/4B3/q4N2/5PPP/2RQ1RK1 w - - 0 1
August 25, 2007
Smothered Mate
August 18, 2007
Displacement Attacks
In chess, a displacement attack drags a defender away from the piece it guards, allowing a capture of a previously guarded piece. Usually this involves a sacrifice, a check, or both. Black to move:
FEN 6k1/2b3p1/p7/2rp4/8/P1P2P2/1B1qQK2/5R2 b - - 6 1
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August 07, 2007
Double Check
In chess, double checks force the King to move, as no one piece can block or capture both attackers.1 If the King cannot move, then the check is mate. In the following example, White is to move next.
FEN 6rk/8/p7/1p6/8/2R5/1B4PP/1b4K1 w - - 0 1
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June 24, 2007
Reading, 乱, and Rostropovich
Winning Chess Tactics (revised) is a good introduction to Chess tactics, though a few diagrams have mistakes, which makes learning difficult.
- Play Stronger Chess by Examining Chess960: Usable Strategies of Fischer Random Chess Discovered covers Chess960 in great detail. Includes easy (and unbiased!) methods for board setup, rules for notation, castling, and methods to reduce the advantage of White starting. Most interesting is the discussion of various layouts with regard to 2nd rank pawn support (or lack thereof), 4th rank pawn support, how the Knights interact, and other considerations Chess960 requires.
乱 [Ran] sets King Lear (more or less) in Feudal Japan: incredibly well done. Been working through works by Akira Kurosawa via Netflix. Netflix very handy, with the nearest movie store being of limited selection, and the rest a fair ways away (and uphill) from me.
Mstislav Rostropovich: Cello Concertos collects concerto and encore recordings from the 1950s. Some tracks suffer from a slight background hiss, though nonetheless excellent and enjoyable music throughout.
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June 19, 2007
Shogi Game Collection Analysis
This Shogi game analysis uses Eric’s games collection, last updated 2006-07-16. The Portable Shogi Notation (PSN) files were converted into a PostgreSQL database using psn-util. SQL then used to analyze the moves. For reference:
| Side Name | Chess Equivalent | King |
| 先手 [せんて: Sente] | White | 玉 |
| 後手 [ごて: Gote] | Black | 王 |
Sente and Gote used hereafter to denote the sides, as other documentation I’ve found uses Black and White as in Chess, but with Black going first.
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June 16, 2007
Knight
June 05, 2007
Shogi Stuff
A chess board for Shogi players. Or to confuse people trying to follow your chess games. The Queen has no equivalent in Shogi, so hopefully 妃 suffices. In chess, color differentiates the Kings, though I retained the 玉 abbreviation for the black king. Unlike chess, black moves first.
Chess-like Shogi pieces to print and use on a chess board. These use the Shogi piece outline, so one knows which side the piece belongs to without coloring.
And finally, a Shogi game move marker, for highly asynchronous games. Fold down center line and staple together edges.
Also consider a rescue vehicle for wounded kings.
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May 05, 2007
Fuzzy Chess
March 01, 2007
MacShogi
MacShogi, coupled with games databases, makes a good study tool for Shogi. Nowhere near the features or computer-assisted learning in Chess programs, though. Additional commentary in the games would be nice, to answer questions such as “why does the rook back up in this situation” or “what is the player trying to do here?”
Darwin Ports hosts a usable compile of gnushogi, which allows graphical play in xshogi, and computer play capable of trouncing the unwary.
February 18, 2007
Sicilian Opening
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February 10, 2007
Sightseeing
Chess/Shogi take III. Shogi set arrived at work, but could not round up enough folks for a try at bughouse Shogi…
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January 30, 2007
Gold General
January 28, 2007
Red Hot Pawn
Been playing chess online at Red Hot Pawn as thrig. Good website interface, and offers rated games, so you know roughly where you stand against other players.
For a great change of pace, try Shogi. Piece drops play an important role, unlike chess, and the different piece types and upgrading provides for interesting gameplay. Check out maka dai dai Shogi—the name surely the product of a great drinking session—for a crazy cast of characters.
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November 09, 2006
Chess960 position generator
Wrote chess960open to generate Chess960 opening positions for White. Here’s one possibility:
| ♗ | ♖ | ♔ | ♖ | ♘ | ♕ | ♘ | ♗ |
| Bishop | Rook | King | Rook | Knight | Queen | Knight | Bishop |
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September 05, 2006
Chess Books
Trying out a series of chess books by Yasser Seirawan. Started with Winning Chess Tactics, but quickly realized lacked the fundamentals covered in first book Play Winning Chess (force, time, space, and pawn structure).
For extra practice, installed chess board at work. Great time waster (and developer snare). Run open games where anyone free to play. This leads to odd chess games, where one side dominates, or numerous tactics changes as different players cast their opinion.
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