1 \input texinfo @c -*-texinfo-*-
3 @c % ** Start of header.
4 @setfilename gnushogi.info
5 @settitle GNU Shogi manual
10 * gnushogi: (gnushogi). Japanese chess
13 @setchapternewpage odd
15 @c ==================================
16 @c TeX-specific macros
17 @c ==================================
21 @c ==================================
22 @c info-specific macros
23 @c ==================================
27 @c ==================================
28 @c Summary description and copyright.
29 @c ==================================
33 This file describes how to use GNU shogi,
34 a program which plays Shogi (Japanese chess).
36 Copyright (C) 2013 Yann Dirson and the Free Software Foundation, Inc.
37 Copyright (C) 1999 Michael C. Vanier and the Free Software Foundation, Inc.
39 Permission is granted to make and distribute verbatim copies of
40 this manual provided the copyright notice and this permission notice
41 are preserved on all copies.
44 Permission is granted to process this file through TeX and print the
45 results, provided the printed document carries copying permission
46 notice identical to this one except for the removal of this paragraph
47 (this paragraph not being relevant to the printed manual).
50 Permission is granted to copy and distribute modified versions of this
51 manual under the conditions for verbatim copying, provided that the entire
52 resulting derived work is distributed under the terms of a permission
53 notice identical to this one.
55 Permission is granted to copy and distribute translations of this manual
56 into another language, under the above conditions for modified versions,
57 except that this permission notice may be stated in a translation approved
58 by the Free Software Foundation.
62 @c =========================================
63 @c End of summary description and copyright.
64 @c =========================================
67 @c ====================
68 @c Title and copyright.
69 @c ====================
73 @comment The title is printed in a large font.
74 @center @titlefont{GNU Shogi (Japanese chess)}
77 @c The following two commands start the copyright page.
79 @vskip 0pt plus 1filll
80 Copyright @copyright{} 2013-2014 Yann Dirson and the Free Software Foundation
81 Copyright @copyright{} 1999 Michael C. Vanier and the Free Software Foundation
85 @c ===========================
86 @c End of title and copyright.
87 @c ===========================
90 @c =========================
91 @c Top node and master menu.
92 @c =========================
94 @node Top, (dir), (dir), (dir)
95 @top GNU Shogi (Japanese chess)
99 * Introduction:: What is GNU shogi?
100 * About shogi:: General information, rules, etc.
101 * gnushogi:: How to play GNU shogi (gnushogi).
102 * References and links:: Where to go for more information.
104 * Bugs:: Where and how to report bugs.
110 This document describes GNU shogi, a program which plays Japanese chess
111 (shogi) against a human opponent.
114 @c ================================
115 @c End of top node and master menu.
116 @c ================================
123 @node Introduction, About shogi, Top, Top
124 @chapter Introduction
127 GNU shogi is a program that plays shogi, the Japanese version of chess,
128 against a human (or computer) opponent. This file describes how to use
129 GNU shogi and also gives background information about the game of shogi.
131 This file describes GNU Shogi version 1.4.1, but most of it was
132 written for version 1.3.2 by Mike Vanier
133 @email{mvanier@@cs.caltech.edu}, maintainer of GNU shogi at that time.
135 GNU Shogi is currently maintained by Yann Dirson
136 @email{ydirson@@free.fr}.
139 GNU Shogi is actually one program, 'gnushogi', the text-based program
140 which also contains the game-playing engine. By default it will play
141 Standard Shogi, but can be built to play Mini Shogi (with GNU Shogi
142 1.4.x, you will need to do that explicitely using `./configure
143 --enable-minishogi', but 1.5 will make this more straightforward).
145 Most players will just run GNU Shogi through one of the compatible
146 graphical interfaces:
150 @uref{http://repo.or.cz/w/tagua/yd.git, Tagua}, a KDE-based GUI for
151 Chess and Shogi. Developement stopped several years ago, and it is
152 still somewhat maintained at Debian. Probably the most sophisticated
153 and best-looking free GUI available today.
156 @uref{https://alioth.debian.org/projects/omaha/, Omaha}, a generic
157 board-game GUI, supporting Shogi and other games, with currently only
158 a Gtk2-based UI. Still under developement, but already usable for
162 @uref{https://github.com/pcapriotti/kaya, Kaya}, a small KDE-based GUI
163 successor to Tagua, but development of this still young program seem
167 @uref{http://www.gnu.org/software/xboard/, XBoard/Winboard}, a GUI for
168 much more than Shogi, part of the GNU Project. Patches for GNU Shogi
169 to support it are being integrated into the developement version,
170 1.4.x and earlier versions cannot talk to it.
173 @uref{http://ftp.gnu.org/gnu/gnushogi/, XShogi}, an X-Window graphical
174 interface to gnushogi, forked off GNU XBoard years ago, and far from
175 today's UI standards. It has barely been maintained recently, while
176 XBoard has grown much and is able to play Shogi, and will be soon
179 The GNU Shogi distribution used to contain the 'xshogi' program, In
180 future versions, GNU Shogi will be able to use XBoard as a GUI and
181 XShogi will be retired. XShogi is still available as a separate
182 source archive on the GNU project FTP server.
187 Disclaimer: I use the personal pronouns ``him'', ``his'' etc. to refer
188 to a shogi player regardless of gender. That's easier than writing
189 ``his or her'' all over the place. I don't mean to infer that women
190 don't play shogi; in fact shogi is very popular in Japan among women as
194 @node About shogi, gnushogi, Introduction, Top
195 @chapter About the game of shogi
199 ``Japanese chess cedes nothing in depth or beauty to the European
200 game... it is at least as interesting.''
202 --- Alexander Alekhine @*
203 (quoted in David Pritchard, @cite{The Encyclopedia of Chess Variants})
205 ``... shogi [is] by far the most complex form of chess that has ever
206 achieved widespread popularity.''
208 --- R. Wayne Schmittberger, @cite{New Rules for Classic Games}
211 Shogi is the version of chess played in Japan. It is strikingly
212 different from standard chess (which I shall refer to henceforth as
213 ``international chess'') and also to all other regional variants,
214 because captured pieces can re-enter play on the side of the capturer.
215 This has several interesting effects on the play of the game:
219 Shogi is much more complex than international chess, at least in
220 terms of the average number of possible moves per turn (estimated at
221 about 35 for chess and at about 80 for shogi).
224 There are almost no draws (about 1-2% of all games in professional play).
227 Exchanges complicate the play rather than simplifying it.
230 There are no ``endgames'' in the standard chess sense; all pieces remain
231 in play throughout the game. Games typically end in a race to
232 checkmate the other player before being checkmated oneself.
235 Ownership of a piece is not indicated by the color of the piece;
236 instead, pieces are wedge-shaped and point towards the opponent. The
237 name of the piece is inscribed in Kanji characters on the front of the
241 Most importantly: it's more fun than other forms of chess :-)
245 Shogi is extremely popular in Japan; it has been estimated that 20
246 million Japanese can play shogi, of which perhaps 1 million are active
247 players. It is even more popular there than the game of go, Japan's
248 other favorite board game. There are a number of professional players
249 who make a considerable amount of money playing in shogi tournaments,
250 and the game receives extensive newpaper and television coverage.
251 Despite this, the game has yet to become popular outside of Japan. Part
252 of this is because the Kanji characters on the pieces scare away some
253 people, but mostly it's due, I think, to lack of exposure to the game
254 and to the difficulty of finding opponents. I hope that GNU shogi will
255 help introduce shogi to a wider audience.
259 * The rules of shogi::
263 * Differences between shogi and chess::
268 @c -------------------------------------------------------
270 @c The rules of shogi.
272 @c -------------------------------------------------------
274 @node The rules of shogi, Sample game, About shogi, About shogi
275 @section The rules of shogi
278 Shogi is a two-person abstract strategy board game with full information
279 (i.e. all pieces and moves are visible to both players at all times).
280 It is in the chess family, being descended from the same ancestral game
281 as international chess: the Indian game of Chaturanga. The two players
282 are referred to as ``Black'' and ``White'', with Black moving first
283 (unlike in international chess, where White moves first), and with
284 movement alternating between the two players. Note that ``Black'' and
285 ``White'' are just names; the pieces are not colored. Instead, they are
286 flat, wedge-shaped pieces which point towards the opponent. The
287 identity of a given piece is indicated by two Japanese Kanji characters
288 on each piece. In fact, only the top character is needed to identify
289 the piece and thus only the top character is used in shogi diagrams. I
290 will use alphabetical equivalents in the diagrams here; to see what the
291 Kanji characters look like, start up a graphical interface
292 (@pxref{Introduction}) and compare the starting setup there with the
293 starting setup in this file (@pxref{The opening setup}).
295 The object of the game is to capture the opponent's King. The board is
296 a grid of 9x9 uncolored squares, and pieces are placed on the squares.
297 Each player begins with 20 pieces, described in the next section.
298 Capture is by displacement, as in international chess.
302 * The moves of the pieces::
303 * The opening setup::
304 * Promotion of pieces::
309 * Notes for chess players::
313 @c The moves of the pieces.
315 @node The moves of the pieces, The opening setup, The rules of shogi, The rules of shogi
316 @subsection The moves of the pieces
319 Each player at the beginning of a shogi game has a total of 20 pieces of
320 eight different types. The moves of the shogi pieces can be divided
321 into three classes: ``stepping'' pieces, that only move one square at a
322 time; ``ranging'' pieces that move any number of unobstructed squares in
323 a line, and ``jumping'' pieces that can jump over obstructing pieces to
324 reach their destination squares. Most pieces can also promote to
325 different (usually stronger) pieces under certain circumstances (see the
326 next section). All pieces capture the same way that they move (even
327 pawns). The piece moves and promotions are as follows; each piece name
328 is followed by the standard piece abbreviation:
333 The king (K). The king can move one square in any horizontal, vertical,
334 or diagonal direction, just like the king in international chess. The
335 king does not promote.
338 The rook (R). The rook can move any number of squares in a horizontal
339 or vertical direction. The rook is the same as the rook in
340 international chess (except that it can promote). A rook promotes to a
341 ``dragon king'' or ``dragon'' for short (often just referred to as a
342 ``promoted rook''), which can move as a rook or can move one square in
343 any diagonal direction.
346 The bishop (B). The bishop can move any number of squares in a diagonal
347 direction. The bishop is the same as the bishop in international chess
348 (except that it can promote). A bishop promotes to a ``dragon horse''
349 or ``horse'' for short (often just referred to as a ``promoted
350 bishop''), which can move as a bishop or can move one square in any
351 horizontal or vertical direction. Note: the horse should not be
352 confused with a knight (see below), as they are two completely different
356 The gold general (G). A gold general can move one square in any
357 horizontal or vertical direction, or one square in a forward diagonal
358 direction. Gold generals do not promote.
361 The silver general (S). A silver general can move one square in any
362 diagonal direction, or one square straight forward. A silver general
363 promotes to a gold general.
366 The knight (N). A knight can move one square straight forward followed
367 by one square to either forward diagonal, jumping over intervening
368 pieces if any. In other words, a knight moves like its international
369 chess counterpart, but forward only. A knight promotes to a gold
370 general. The knight is the only jumping piece, as in chess.
373 The lance (L). A lance can move any number of squares straight forward.
374 A lance promotes to a gold general.
377 The pawn (P). A pawn can move one square straight forward. The pawn
378 captures the same way that it moves, in contrast to international chess.
379 There is also no initial two-space move for pawns and no
380 @emph{en-passant} capture. A pawn promotes to a gold general; a
381 promoted pawn is usually known as a ``Tokin''.
386 @c The opening setup.
388 @node The opening setup, Promotion of pieces, The moves of the pieces, The rules of shogi
389 @subsection The opening setup
390 @cindex Opening setup
392 The opening setup for shogi is as follows:
397 +--------------------------------------------+
398 | wL | wN | wS | wG | wK | wG | wS | wN | wL | a
399 +--------------------------------------------+
400 | | wR | | | | | | wB | | b
401 +--------------------------------------------+
402 | wP | wP | wP | wP | wP | wP | wP | wP | wP | c
403 +--------------------------------------------+
404 | | | | | | | | | | d
405 +--------------------------------------------+
406 | | | | | | | | | | e
407 +--------------------------------------------+
408 | | | | | | | | | | f
409 +--------------------------------------------+
410 | bP | bP | bP | bP | bP | bP | bP | bP | bP | g
411 +--------------------------------------------+
412 | | bB | | | | | | bR | | h
413 +--------------------------------------------+
414 | bL | bN | bS | bG | bK | bG | bS | bN | bL | i
415 +--------------------------------------------+
419 @c The following TeX macros are taken with permission from
420 @c "TeX for the Beginner" by Wynter Snow.
423 \def\startline{\par\nobreak\noindent}
425 {\obeylines\obeyspaces%
426 \gdef\beginVerbatim{\bigbreak%
429 \obeylines\obeyspaces%
432 \gdef\endVerbatim{\endgroup\bigbreak}
437 +--------------------------------------------+
438 | wL | wN | wS | wG | wK | wG | wS | wN | wL | a
439 +--------------------------------------------+
440 | | wR | | | | | | wB | | b
441 +--------------------------------------------+
442 | wP | wP | wP | wP | wP | wP | wP | wP | wP | c
443 +--------------------------------------------+
444 | | | | | | | | | | d
445 +--------------------------------------------+
446 | | | | | | | | | | e
447 +--------------------------------------------+
448 | | | | | | | | | | f
449 +--------------------------------------------+
450 | bP | bP | bP | bP | bP | bP | bP | bP | bP | g
451 +--------------------------------------------+
452 | | bB | | | | | | bR | | h
453 +--------------------------------------------+
454 | bL | bN | bS | bG | bK | bG | bS | bN | bL | i
455 +--------------------------------------------+
460 Here, ``b'' stands for ``black'' and ``w'' stands for ``white'', so
461 that, for instance, ``bL'' means ``black lance''. The numbers above the
462 files and the letters to the right of the ranks represent the most
463 common notation system used for shogi by westerners (the Japanese also
464 use Arabic numerals for the files but use Japanese numerals for the
468 @c Promotion of pieces.
470 @node Promotion of pieces, Drops, The opening setup, The rules of shogi
471 @subsection Promotion of pieces
472 @cindex Piece promotion
474 In sharp contrast to international chess, where only pawns can promote
475 to higher-ranked pieces, most of the pieces in shogi can promote. The
476 promoted ranks are discussed in the section on piece moves (@pxref{The
477 moves of the pieces}) but are repeated here for reference:
482 promotes to gold general (called a `tokin' in this case only).
485 promotes to gold general.
488 promotes to gold general.
491 promotes to gold general.
497 promotes to ``dragon horse'' or just ``horse'' for short. The horse can
498 move as a bishop or can move one square in any orthogonal direction.
501 promotes to ``dragon king'' or just ``dragon'' for short. The dragon
502 can move as a rook or can move one square in any diagonal direction.
509 The three ranks furthest away from each player constitute his/her
510 ``promotion zone''. A player may, but is not required to, promote a
511 piece after making a move in which the piece begins and/or ends in the
512 promotion zone. Thus you can promote a piece when moving the piece into
513 the promotion zone, out of the promotion zone, or entirely within the
514 promotion zone. Promotion is mandatory in these cases:
518 @item You must promote a pawn or a lance after moving it to the last rank.
520 @item You must promote a knight after moving it to either of the last
525 These forced promotions ensure that a piece cannot be moved to a square
526 from which it would have no further move.
528 Pieces ``dropped'' onto the board (@pxref{Drops}) always drop in the
529 unpromoted state, even if they drop into the promotion zone.
535 @node Drops, Winning the game, Promotion of pieces, The rules of shogi
539 When a player captures a piece, that piece is not removed from play.
540 Instead, it becomes the property of the capturer and can re-enter play
541 by being placed on (almost) any vacant square during the player's move.
542 This is known as a ``drop'' and counts as a full move (in other words,
543 you can either move a piece on the board or drop a piece onto the board
544 during your move, but not both). All pieces drop in the unpromoted
545 state. Pieces may be legally dropped in their promotion zone, but they
546 do not promote on that turn.
548 There are several restrictions on drops:
552 @item A pawn may not be dropped onto a file if there is already an
553 unpromoted pawn belonging to the same player on that file. It is legal
554 to drop a pawn on a file which contains a @emph{promoted} pawn belonging
555 to the same player, however.
557 @item A pawn may not be dropped to give immediate checkmate on the
558 move. A pawn is, however, permitted to be moved on the board to give
559 immediate checkmate. This is a curious rule, and if anyone knows the
560 reason for it I would appreciate it if they would contact me and explain
563 @item A pawn or piece may not be dropped onto a square from which they
564 would have no legal move. This means that pawns and lances may not be
565 dropped onto the last rank, and the knight may not be dropped onto the
566 last or second-to-last rank.
570 It is entirely permissible (and often advisable) to drop a piece or pawn
571 between one's King and an attacking ranging piece. For this reason,
572 the final checkmating move is nearly always an attack on the King from
573 an adjacent square (except for an attack by a Knight).
575 Captured pieces are said to be pieces ``in hand''.
577 The drop is the primary distinguishing feature of Japanese chess, shared
578 with no other popular chess-type game. It gives shogi a very aggressive
579 quality, and dramatically increases the number of possible moves once a
580 few pieces have been captured. Another interesting feature of shogi is
581 that exchanges complicate play rather than simplifying it (as in
582 international chess), because of the drop rule.
587 @node Winning the game, Draws, Drops, The rules of shogi
588 @subsection Winning the game
589 @cindex Winning the game
591 A game of shogi is won by capturing the opponent's king. In general,
592 this is done by checkmating the king: attacking the king in such a way
593 that the king cannot be defended no matter what the defending player
594 moves. Note, though, that there is no rule that requires a player to
595 defend a king which is being attacked. However, if he does not defend
596 his king, the opponent is entirely free to capture it on the next move,
597 thus winning the game. As in international chess, in practice most
598 games end by resignation when one player realizes that he cannot escape
604 @node Draws, Handicaps, Winning the game, The rules of shogi
608 There are very few draws in shogi; only about 1-2% of professional games
609 end in a draw. One reason for this is that material can never be
610 depleted as in chess, because captured pieces are constantly re-entering
611 play as a consequence of the drop rule. In fact, most of the ways a
612 game can be drawn in chess are not allowed in shogi:
616 @item Draws cannot be offered.
618 @item There is no fifty-move rule.
620 @item A stalemate counts as a win for the stalemater. Stated otherwise:
621 if you can't move, you lose.
623 @item Perpetual check is illegal (see below).
627 There are only two legal ways in which a draw can occur:
631 @item A position (including the pieces in hand) occurs 4 times with the same
632 player to move (called ``Sennichite''). However, if this is caused by
633 consecutive checks (direct attacks on the King, threatening to capture
634 it on the next move) by one side, the player giving these checks loses
635 the game. In other words, perpetual check results in a loss for the
636 attacker who recreates the same position the 4th time.
638 @item Both players have moved their King into the the promotion zone (or they
639 cannot be prevented from doing so) and the Kings cannot be checkmated.
640 A King who has entered the promotion zone is known as an ``entering
641 King''; due to the forward orientation of most shogi pieces, it is very
642 hard to mate such a King. In that case the players may decide to count
643 their pieces as follows: the King does not count, the Rook and Bishop
644 count as 5 points, and all other pieces as one point. Promotion is
645 disregarded. If both players have at least 24 points the game is a draw
646 (called ``Jishogi''). If a player has less, he loses the game.
648 Of course, a player can refuse to count pieces when he still has mating
649 chances or chances to gain material which would affect the outcome of
650 the counting. There is no strict rule about what to do if this is not
651 the case, but nonetheless a player refuses to count up (e.g. because he
652 does not have enough points for a draw). It has been generally accepted
653 that in such a case the game ends and the pieces are counted after one
654 player has managed to get all his pieces protected in the promotion
661 @node Handicaps, Notes for chess players, Draws, The rules of shogi
662 @subsection Handicaps
665 Unlike international chess, shogi has a well-established handicap system
666 which is used when players of different strengths play against each
667 other. Handicaps range from small to huge, which makes it possible for
668 weak players to play against even very strong players and have an even
671 Shogi players are ranked as follows: the weakest rank is around 15
672 ``kyu'', which represents a beginner. 14 kyu is higher than 15 kyu, 13
673 kyu is higher still, and so on until you get to 1 kyu. The next highest
674 rank is 1 ``dan'', followed by 2 dan, 3 dan and so forth. The highest
675 amateur rank is 6 dan; professionals go up to 9 dan. However,
676 professional ranks are not the same as amateur ranks; a professional 1
677 dan is @emph{much} stronger than an amateur 1 dan. This system is
678 similar to that used by go players (and also other Japanese sports such
681 A handicap consists of the stronger player playing White and removing
682 one or more pieces from his side of the board at the start of the game.
683 These pieces are permanently removed from play; they are not in hand.
685 The following is a list of the accepted handicaps, from weakest to
686 strongest. The degree of the handicap, represented by the position in
687 the list, represents the difference in rank between the two players for
688 which the handicap is appropriate. These rules are taken from the books
689 ``Shogi for Beginners'' by John Fairbairn and ``The Art of Shogi'' by
690 Tony Hoskings (@pxref{References and links}) and, I believe, represent
691 current Japanese practice.
696 The stronger player removes his left lance (on 1a).
699 The players play a two-game match; in the first game the stronger player
700 removes his left lance (on 1a), while in the second game he removes his
704 The stronger player removes his bishop.
707 The stronger player removes his rook.
710 The stronger player removes his rook and left lance.
713 The players play a two-game match; in the first game the stronger player
714 removes his rook and left lance (on 1a), while in the second game he
715 removes his rook and bishop.
718 The stronger player removes his rook and bishop. This is usually called
719 a ``two-piece'' handicap.
722 The stronger player removes his rook, bishop, and both lances. This is
723 called a ``four-piece'' handicap.
726 The stronger player removes his rook, bishop, both lances, and both
727 knights. This is called a ``six-piece'' handicap.
730 The stronger player removes his rook, bishop, both lances, both knights,
731 and both silvers. This is called an ``eight-piece'' handicap.
735 Another advantage of playing handicap games is that the handicaps alter
736 the optimal strategy for both players. For instance, handicaps all have
737 their own opening lines which may bear little or no resemblance to those
738 used in non-handicap shogi. This means that when learning handicap
739 shogi, you are essentially learning completely new games which use the
742 The reader may wonder how on earth a player giving an eight-piece
743 handicap, say, could possibly hope to win. Don't forget, though, that
744 in shogi the opponent's pieces can be captured and then become part of
745 one's own army. Thus, if the opponent plays badly enough, the number of
746 pieces will soon even out.
749 @c Notes for chess players.
751 @node Notes for chess players, , Handicaps, The rules of shogi
752 @subsection Notes for chess players
754 Here are a few miscellaneous things that may confuse chess players.
755 Some of these have been mentioned elsewhere, but they bear repeating.
758 @item There is no queen.
760 @item Pawns capture the same way they move. There is no initial
761 two-space pawn move and no @emph{en-passant} move.
763 @item There is no special castling move. There @emph{are} a large
764 number of possible defensive formations referred to as ``castles''
765 (@pxref{Sample game}) but there is no need for special moves to create
768 @item A given piece can only promote to @emph{one} other kind of piece.
776 @node Sample game, Mating problems, The rules of shogi, About shogi
780 @c This will have to be spruced up for the TeX version...
782 This game was annotated by Pieter Stouten (@pxref{References and
783 links}). I have made some minor corrections. Note that captures are
784 denoted by the ``x'' symbol e.g. Rx3f and drops are denoted by the ``*''
785 symbol e.g. R*3f. Check is indicated by a ``+'' after the move,
786 e.g. R3f+. I recommend you use a graphical interface to play along with this
787 game. In xshogi simply hit the ``Force Moves'' button after starting
788 up, while in gnushogi enter the word ``force'' at the prompt. This will
789 allow you to enter moves for both sides.
791 Note also that the move numbering system used here is the chess-type
792 system where one move means one move by each player. The Japanese count
793 one move made by each player as two moves.
795 ---------------------------------------------------------------------------
797 Below you will find (the English translation of) an annotated game which
798 was published in the Dutch Shogi magazine ``81'' and in the Dutch
799 beginners booklet. It has proven to be a very useful game to explain
800 some basic principles of Shogi. Also, it is a rather straightforward
801 game compared to professional games where in most cases very diffuse
802 middle game fights take place.
804 Pieter Stouten, 14th May 1990.
806 ---------------------------------------------------------------------------
808 Black: Michael Trent (1-dan). White: David Murphy (2-dan).
810 1. P2f P3d 2. P2e B3c @*
811 [ This move is necessary, as otherwise white can exchange pawns: 3. P2d
812 Px2d 4. Rx2d. He would thus get a pawn in hand and open up his rook
816 [ White closes the bishop diagonal again. He plans to play ranging rook
817 (the rook goes to 5b, 4b, 3 or 2b; a defensive strategy) and in that
818 case he'd better avoid an exchange of bishops. One of the reasons is
819 that he will have problems developing his pieces without leaving holes
822 4. S4h R3b 5. P3f S4b 6. K6h K6b @*
823 [ In general the rook plays an important role in the attacks. It is
824 wise to move the king away from the area where the initial fights will
825 be and both players act according to the Shogi proverb ``keep the rook
828 7. K7h K7b 8. P5f P5d 9. G4i-5h G4a-5b @*
829 [ Both players use their second gold general to build their castle. ]
832 [ In itself this move is not bad. However, it will become clear that
833 black plans a quick attack and in that case it is wiser to omit this
836 10... S5c 11. P1f P1d @*
837 [ The advance of the edge pawns must be timed very well. The remark at
838 black's tenth move applies here too: this move is good if black wants to
839 play a slow game, because it eliminates a future B1e. ]
841 12. P4f K8b 13. N3g S7b @*
842 [ Black develops his knight in order to start an attack over the second,
843 third and fourth files. White strengthens his king's position and
844 awaits the attack. He aims at a counterattack as soon as black has
845 broken through into the white camp. Probably white's breakthrough will
846 take place later, but he has good compensation in the form of a stronger
847 castle. This theme occurs very often in static rook versus ranging rook
851 [ Black starts his attack and white puts up a very passive defence. His
852 rook has a hard task now to penetrate the black position. Moreover, he
853 blocks his own bishop. It seems much better to start a counterattack
854 with 14... P3e, later to be followed by B2b, B5a or Bx4d in order to use
855 his rook more actively. ]
857 15. Px4d Sx4d 16. P*4e S5c @*
858 [ 16... Sx4e is more active. A silver general is normally more valuable
859 than a knight, but white gets two pawns in hand and black none, while
860 the knight might come in handy for white too. ]
862 17. Bx3c+ Nx3c 18. P2d Px2d @*
863 [ Black threatens to break through and white has to consider taking the
864 pawn on 2d or starting a counterattack with Nx4e. If he chooses the
865 latter, black can play Px2c+ followed by +P3c. The disadvantage is the
866 black ``tokin'' (=promoted pawn) that white will get in his camp; the
867 advantage is that it will cost black two more moves to promote his rook.
868 Because white did not trust that the result after engaging in a
869 ``semeai'' (=mutual attack) with 18...Nx4e would give a positive result,
870 he captured the pawn on 2d. Making the right decision in moments like
871 this often makes the difference between a win and a loss: miss one
872 attacking chance and you will be forced to defend the whole game until
873 the unavoidable defeat; on the other hand, an unsound attack can destroy
874 all ``aji'' (=potential, meaning possibilities, threats) without getting
875 anything in return. ]
877 19. Rx2d Nx4e 20. Nx4e Rx4e 21. R2a+ P*4g @*
878 [ Now it becomes clear why black's 10. S6h was not good. Had this move
879 been omitted, then white would not have had the time to play 13... S7b
880 and after R2a+ the gold on 6a would hang. Thus black would have kept
881 ``sente'' (=initiative). Instead of 21... P*4g, B*6d is a very good
882 move, because after 22. P*2h black does not have a pawn in hand anymore
883 and he is being threatened with the annoying 22... N*4f 23. G5g N3h+
884 24. S4g +N4h also. Black can also counter 21... B*6d with 22. N*3g.
885 White would then reply with 22... R4b 23. B*3c P*4g 24. Bx4b+ Sx4b. The
886 white rook has played its role and instead of spending moves on saving
887 it white starts to scatter black's defences by successive pawn drops on
888 the fourth file: 25. Gx4g P*4f 26. G5g N*6e 27. G5h P4g+ 28. Gx4g P*4f.
889 This analysis was provided by Kato Hifumi, 9-dan professional (the
890 highest regular grade). Destroying the coherence of the enemy pieces
891 (their shape) by dropping pawns is one of the most important Shogi
892 techniques. With the actual move 21... P*4g white missed a good
895 22. Sx4g P*4f 23. B*3g Px4g+ 24. +Rx6a +Px3g @*
896 [ 23. B*3g seems pointless, but a closer look reveals that it is
897 actually quite mean. On move 24 white cannot capture black's ``Ryu''
898 (=dragon =promoted rook) with his silver: 24... Sx6a 25. N*7d K7b
899 26. G*8b mate. By attacking the front of the white castle and
900 threatening to mate him there, black has the chance to break down the
901 white defences from the side. ]
904 [ Here 25... B*4d would be much better, because it is defensive and
905 attacking at the same time. After e.g. 26. G*4c Bx9i+ 27. Gx5c black
906 threatens 28. +Rx7b Kx7b 29. S*6a K8b 30. S*7a Kx7a 31. G*7b mate.
907 White is one move quicker, however. He has the following beautiful
908 ``tsume'' (mating sequence where every move is check): 27... N*8f 28. Px8f
909 S*8g 29. Kx8g B*9h 30. K7h Bx8i+ 31. K8g +B8i-8h 32. K9f L*9e mate.
910 This illustrates the sharpness of Shogi: one move can make the
911 difference between winning and losing. ]
914 [ This move eliminates white's last chances. 26... R4b 27. +Rx4b Sx4b
915 28. R*4a seems annoying, but after 28... B*3c 29. S7g B*3b white wins
916 the rook and with his ``tokin'' on 3g there still is some hope. ]
919 [ White cannot defend anymore, so he starts a desperate attack. Black
920 does not lose the right track, however. ]
922 28. Nx5c+ +Px5h 29. +Nx6b +Px6h 30. Gx6h N*8f 31. Px8f B*6i 32. Gx6i
923 R4h+ 33. N*6h +Rx6h 34. Gx6h S*8g 35. Kx8g N*9e 36. K7h Resigns @*
924 [ White resigns here, because after 36... B*8g 27. K7g his attack has
934 @node Mating problems, Shogi variants, Sample game, About shogi
935 @section Mating problems
937 One good way to improve at shogi is to solve mating problems. There are
938 several types of these problems, but the most common is called a
939 ``tsume-shogi'' problem, or ``tsume'' problem for short. In a tsume
940 problem, all pieces that are not on the board are assumed to be in the
941 opponent's hand (except for your King, which is usually not shown).
942 Every move you make must be check until the final checkmate. Your
943 opponent may play any piece on the board or drop any of his pieces in
944 hand in order to prevent the mate. In a properly constructed tsume
945 problem, all of your pieces on the board and in hand must be essential
946 to the solution. One consequence of this is that all of your pieces in
947 hand must be played during the solution. There should only be one
948 correct solution for the given number of moves. Tsume problems use
949 Japanese-style move numbering; thus, a problem where you move (and give
950 check), your opponent moves, and you move to give checkmate is called a
951 three-mover. Here is a really trivial three-mover:
976 \def\startline{\par\nobreak\noindent}
978 {\obeylines\obeyspaces%
979 \gdef\beginVerbatim{\bigbreak%
982 \obeylines\obeyspaces%
985 \gdef\endVerbatim{\endgroup\bigbreak}
1008 Here, Black plays G*2b, White plays K1c, and Black plays G*1d mate.
1009 More typical tsume problems range from 5 moves to arbitrarily high
1010 numbers of moves, and they can be quite brain-busting. Tsume problems
1011 may seem artificial, but in the closing stages of the game where both
1012 players have a lot of pieces in hand, it is often necessary to give
1013 check at every move, or else your opponent will start a counterattack
1014 and will mate you before you mate him. A tsume problem is a worst-case
1015 scenario for the attacker: you have to mate your opponent even though he
1016 has every piece not on the board in hand, which means you have to
1017 develop sharp attacking skills. Many more tsume problems can be found
1018 on the internet; I particularly recommend Patrick Davin's ``Shogi
1019 Nexus'' (@pxref{References and links}).
1027 @node Shogi variants, Differences between shogi and chess, Mating problems, About shogi
1028 @section Shogi variants
1029 @cindex Shogi variants
1035 @cindex Tenjiku Shogi
1036 @cindex Dai-dai Shogi
1037 @cindex Maka-dai-dai Shogi
1039 @cindex Kyoku Tai Shogi
1041 Several historical variants of shogi exist. Most of these were invented
1042 before modern shogi (in some cases hundreds of years before), are much
1043 larger than modern shogi and are not played with drops. Thus, in many
1044 ways they are really more like giant chess games than like modern shogi.
1045 The only one of these games to have survived in Japan is Chu (middle)
1046 shogi, which is still played a little bit. Thanks to the efforts of
1047 George Hodges and John Fairbairn of the Shogi Association (two British
1048 shogi enthusiasts), these games were resurrected and rules and sets for
1049 them can still be purchased from George Hodges (@pxref{References and
1050 links}). I hope to eventually extend GNU shogi so that it can play at
1051 least some of these games. There are also several non-historical
1052 variants of shogi; I don't know much about them but you can find
1053 information about them on the internet (@pxref{References and links}).
1055 The historical variants include:
1060 Tori (bird) shogi, played on a 7x7 board with 32 pieces in all; this is
1061 the only variant that is known to have been played with drops.
1064 Wa shogi, played on an 11x11 board with 54 pieces. This game can be
1065 played with or without drops but the historical evidence favors the view
1066 that it was played without drops. However, most people who have tried
1067 it claim it is a much better game with drops, being even more intricate
1068 than standard shogi.
1071 Chu (middle) shogi, played on a 12x12 board with 92 pieces. This was
1072 (and is) by far the most popular of the variants, and has 21 different
1073 kinds of pieces in the starting line-up alone (along with several others
1074 that appear upon promotion). Unlike modern shogi, there are a
1075 tremendous number of ranging pieces and the game is definitely not
1076 played with drops. There is also an amazing piece called the Lion which
1077 has a double king move and can capture two pieces at once! Chu shogi
1078 has a small but fanatical following, some of whom consider it better
1082 Dai (great) shogi, played on a 15x15 board with 130 pieces. Other than
1083 the larger board, this game is very similar to Chu shogi.
1086 Tenjiku (exotic) shogi, played on a 16x16 board with 176 pieces. This
1087 game is possibly the most complex tactical game in existence. There are
1088 many astoundingly powerful pieces, including one (the Fire Demon) that
1089 can capture up to eight opposing pieces in a single move! Despite the
1090 size of the game, checkmates can occur very suddenly (and often very
1091 early on) if one player makes a wrong move. Tenjiku also has a small
1092 but fanatical following, one of whom (Colin Adams) has written a book on
1093 the game which is available for download at
1094 @uref{http://wayback.archive.org/web/20120717085827/http://www.colina.demon.co.uk/tenjiku.html}.
1097 Dai-dai (great-great) shogi, played on a 17x17 board with 192 pieces.
1098 The opening setup alone has 64 different kinds of pieces! This game and
1099 the larger ones that follow sound pretty outlandish, but they have
1100 actually been played; a game of Dai-dai can supposedly be played in
1104 Maka-dai-dai (great-great-great) shogi, played on a 19x19 board with 192
1105 pieces. For those for whom Dai-dai shogi is just too small :-)
1108 Tai (grand) shogi, played on a 25x25 board with 354 pieces! Until
1109 recently, this was thought to be the biggest chess game ever devised,
1113 Kyoku tai (extremely grand?) shogi, played on a 36x36 board with 402
1114 pieces. The rules for this have just been unearthed in an old Japanese
1115 book. Hopefully someone will soon organize a postal Kyoku tai shogi
1116 championship; maybe their distant ancestors could finish it :-)
1118 It is thought that the really huge games (Dai-dai and up) were never
1119 really played to any significant extent (gee, wonder why?) and were
1120 devised merely so that the creators could have the fun of inventing
1121 enormous games, amazing their friends and confounding their enemies.
1122 However, the games up to Tenjiku shogi at least appear to be quite
1123 playable, assuming one has the time.
1127 Many modern variants have also been devised, usually on small boards,
1128 and often by western people. Those include:
1133 Mini Shogi, played on a 5x5 board with 12 pieces. Its rules are
1134 nearly identical to Standard Shogi, and GNU Shogi has some support for
1138 Judkins Shogi, similar to Mini Shogi on a 6x6 board.
1141 Cannon Shogi, played on a 9x9 board, adds pieces inspired by the
1142 Cannon found in Xiang Qi (chinese chess)
1145 Sannin Shogi, a 3-player variant on an hexagonal board, with specific
1146 rules governing alliance between two players
1149 Kyoto Shogi, Micro Shogi, and several others are much more different.
1154 @c Differences between shogi and chess.
1157 @node Differences between shogi and chess, , Shogi variants, About shogi
1158 @section Differences between shogi and chess
1159 @cindex Shogi vs. Chess
1161 Some differences between shogi and international chess have been
1162 mentioned elsewhere in this document; I summarize them here for people
1163 who are interested in game comparisons. I won't try to deal with the
1164 thorny question of which game is ``better'' although my bias may have
1165 already come through :-) In fact, the drop rule makes the two games so
1166 different in character that arguing over which game is better is like
1167 comparing apples to oranges (you'd be better off comparing chess to Chu
1168 shogi (@pxref{Shogi variants}). However, I believe that if you are a
1169 chess fan you'll really like shogi as well, and shogi is also popular
1170 with many people who don't particularly like chess.
1172 Here are the significant differences between chess and shogi:
1177 In shogi, captured pieces become the property of the capturer and can
1178 re-enter play by being dropped onto almost any vacant square. In chess,
1179 captured pieces are out of the game. Thus, in shogi, piece exchanges
1180 complicate the play significantly while in chess they simplify it.
1183 The shogi board is 9x9; the chess board is 8x8.
1186 Shogi has five pieces with no counterpart in chess: the gold and silver
1187 generals, the lance, the promoted rook and the promoted bishop. Chess
1188 has one piece with no counterpart in shogi: the queen. The knight's
1189 move in shogi is much more restrictive than in chess. Pieces in shogi
1190 generally have a much smaller range of movement than in chess (unless
1194 In shogi, all pieces except the gold general and the king can promote,
1195 but only to one kind of piece. Promotion is easier in shogi because the
1196 promotion zone is closer to the starting position of the pieces
1197 (especially pawns). In chess, only the pawn can promote, but it can
1198 promote to any other piece except the king.
1201 In shogi, pawns capture the same way they move. There is no initial
1202 two-space pawn move and hence no @emph{en-passant} captures. In chess,
1203 pawns capture diagonally which means that opposing pawns can block each
1207 In shogi, you only have one rook and one bishop. Note that the bishop
1208 is not restricted to only one ``color'' square (squares in shogi aren't
1209 colored, but never mind) because promoted bishops can also move one
1210 square orthogonally.
1213 There is no special castling move in shogi. The term ``castle'' is
1214 used in shogi to denote a defensive formation consisting of (usually)
1215 three generals which protect the king. There are many such castles
1216 (about 40 or so have names). @xref{Sample game}.
1219 Draws are much rarer in shogi than in chess. Perpetual check is not
1220 allowed. Stalemate is a virtual impossibility, and is a loss for the
1224 Since pieces are never out of play in shogi, chess-type endgames
1225 involving only a few pieces do not occur.
1228 Shogi games are generally longer than chess games (about 60-70 moves is
1232 Shogi has a well-developed handicap system which is in general use;
1237 The effects of all these differences on play include (in my opinion):
1242 Piece/pawn structures in chess are more rigid than in shogi. Pawns
1243 block each other and pawns, once advanced, cannot ever retreat. In
1244 shogi, you can repair the hole caused by a pawn advance by exchanging
1245 the pawn and dropping it back where you want it. Thus shogi is more
1246 fluid than chess and less ``structural''.
1249 Counterattack is MUCH more common in shogi than in chess. Games
1250 typically end in mutual mating attacks, where each player is trying to
1251 checkmate the other player before being checkmated himself. This makes
1252 tempo incredibly important and also makes sacrificial play quite common.
1255 Attacks involving only ranging pieces are more a feature of chess than
1256 of shogi. A shogi attack typically uses a ranging piece or pieces to
1257 support an attack by short-range pieces (especially generals). It is
1258 very rare to mate a king with a non-adjacent ranging piece in shogi
1259 since the player whose king is threatened can almost always interpose by
1265 @c --------------------
1267 @c --------------------
1269 @node gnushogi, References and links, About shogi, Top
1273 This section describes how to run the ``gnushogi'' program.
1277 gnushogi [ [[-]a] [-b bookfile] [-B binbookfile] [-C] [-h langfile]
1278 [-L langfile] [-r length] [-R] [-s pathname] [-l pathname] [-S binbooksize]
1279 [-t] [-c size] [-T size] [-v] [-x] [-X] arg1 arg2 ]
1283 GNU shogi (gnushogi) plays a game of japanese chess (shogi) against the
1284 user or it plays against itself.
1286 At startup gnushogi reads the binbook file if it is present. It then
1287 looks for a book file. If it is present it adds its contents to the
1288 binbook data. If the binbook file is writable a new combined binbook
1291 Gnushogi is a modified version of the gnuchess program. It has a simple
1292 alphanumeric board display, or it can be used with the xshogi program
1293 under X windows. The program gets its opening moves from the file
1294 gnushogi.bbk which is located in a directory specified in the Makefile.
1295 To invoke the program type:
1300 simple curses based version
1302 @item gnushogi -X (or just gnushogi)
1303 xshogi compatible version
1306 raw test display version
1311 If one argument is given, it is the search time per move in
1312 [minutes:]seconds. So gnushogi 30 will generate one move every 30
1313 seconds, while gnushogi 5:00 will generate one move every 5 minutes.
1315 If two or more arguments are given, they will be used to set tournament
1316 time controls with the first argument of each pair being the number of
1317 moves and the second being the total clock time in minutes[:seconds].
1318 Thus, entering gnushogi 60 5 will set the clocks for 5 minutes (300
1319 seconds) for the first 60 moves, and gnushogi 30 3:30 will allow 3
1320 minutes and 30 seconds for 30 moves.
1322 gnushogi 30 5 1 :30 will allow 5 minutes for the first 30 moves and 30
1323 seconds for each move after that. Up to 4 pairs of controls may be
1326 If no argument is given the program will prompt the user for level of
1333 The book gnushogi.tbk consists of a sequence of openings. An opening
1334 begins with a line starting with a # (the rest of the line is a comment).
1335 Following this is a series of moves in algebraic notation alternating
1336 between black and white separated by whitespace. A move may have a ?
1337 after it indicating this move should never be made in this position. Moves
1338 are stored as position:move so transpositions between openings can take
1343 The hashfile if created should be on the order of 4 megabytes; you can
1344 create such a hashfile by typing ``gnushogi -c 22'' (see below). This
1345 file contains positions and moves learned from previous games. If a
1346 hashfile is used the computer makes use of the experience it gained in
1347 past games. Tests run so far show that it plays no worse with the
1348 hashfile than without, but it is not clear yet whether it provides a
1353 Note: Piece letters are determined by the language file. What is
1354 specified here is the default (English).
1356 Once gnushogi is invoked, the program will display the board and prompt
1357 the user for a move. To enter a move, use the notation 7g7f where the
1358 first letter-number pair indicates the origin square and the second
1359 letter-number pair indicates the destination square. An alternative is
1360 to use the notation P7f where the first letter indicates the piece type
1361 (P,L,N,S,G,B,R,K). To promote append a + the type of the new piece to
1362 the move, as in 2d2c+ or P2c+. Note that you must use capital letters
1363 for the pieces by default.
1365 COMMAND-LINE OPTIONS
1370 Do not search on opponent's time.
1373 Do search on opponent's time.
1375 @item -b @var{bookfile}
1376 Use bookfile for opening book.
1378 @item -B @var{binbookfile}
1379 Use binbookfile for binary opening book.
1382 Create a new HASHFILE. File size is 2^size entries of approximately 65+?
1386 Use curses-based display mode.
1389 Do not use hashfile.
1394 @item -l @var{pathname}
1395 Pathname of the loadfile used with get or xget.
1398 Use language lang from the file gnushogi.lang. If -L is not specified
1399 it uses the first language in the file.
1401 @item -P @var{plylevels}
1402 Number of plys to include in the binbookfile. For generating a
1405 @item -r @var{length}
1406 Rehash @emph{length} times in searching entries for position in
1407 transposition table.
1410 Use raw text display mode. This can be used for dumb terminals or for
1411 systems that don't have curses.
1413 @item -s @var{pathname}
1414 Pathname of the save file to use with the save command.
1417 Size of binbookfile for memory based books. For creating a binbookfile.
1420 Show statistics for HASHFILE.
1423 Set the transposition table size to 2^size entries.
1426 Show version and patchlevel.
1428 @item -x @var{value}
1429 Use value as the evaluation window xwndw.
1432 Use xshogi display mode (the default).
1439 In addition to legal moves, the following commands can be entered at the
1440 gnushogi prompt. Note: command names are determined by the language
1441 file and may vary with the implementation. The default language is
1447 allow algebraic input (not implemented).
1450 change Alpha window (default score + 90).
1453 change Beta window (default score - 90).
1456 toggles beeping after each move (default: on).
1459 updates the current board position on the display.
1462 turns off use of the opening library.
1465 causes the computer to play both sides of a shogi game.
1468 causes the computer to play as White, if the computer was to move
1472 saves a game to disk as a book textfile. The program will prompt the
1473 user for a file name.
1476 toggles game mode time control. Assumes the time specified for time
1477 control is the time for a complete game. Input with the level command
1478 should be the game time and the expected number of moves in a game. go
1479 command must be given.
1482 show coordinates on the display (visual only).
1485 allows the value of @emph{contempt} to be modified.
1488 asks for a piece as color piece, as wb or bn, and shows its calculated
1489 value on each square.
1492 sets level of debugging output if compiled with debug options.
1495 allows the user to change the search depth of the program. The maximum
1496 depth is 29 ply. Normally the depth is set to 29 and the computer
1497 terminates its search based on elapsed time rather than depth. If depth
1498 is set to (say) 4 ply, the program will search until all moves have been
1499 examined to a depth of 4 ply (with extensions up to 11 additional ply
1500 for sequences of checks and captures). If you set a maximum time per
1501 move and also use the depth command, the search will stop at the
1502 specified time or the specified depth, whichever comes first.
1505 toggles easy mode (thinking on opponents time) on and off. The default
1506 is easy mode ON. If easy mode is disabled, the keyboard is polled for
1507 input every so often and when input is seen the search is terminated. It
1508 may also be terminated with a sigint.
1511 allows the user to set up a board position.
1521 command will exit setup mode.
1527 place a promoted pawn on 3b
1530 place a pawn in hand (among the captured pieces)
1534 Pieces are entered by typing a letter (p,l,n,s,g,b,r,k) for
1535 the piece followed by the coordinate. Here, letter case is ignored.
1537 The usual warning about the language file applies.
1543 tells the computer to move first. Computer begins searching for a move.
1547 allows the user to enter moves for both sides. To get the program to
1548 play after a sequence of moves has been entered use the ``black'' or
1552 retrieves a game from disk. The program will prompt the user for a file
1556 tells the computer to move first. Computer begins searching for a move.
1557 (same as ``first'').
1560 use/don't use hashfile.
1563 allows the user to change the minimum depth for using the hashfile and
1564 the number of moves from the beginning of the game to use it.
1567 displays a short description of the commands and the current status of
1571 causes the program to supply the user with its predicted move.
1574 allows the user to set time controls such as 60 moves in 5 minutes etc.
1575 In tournament mode, the program will vary the time it takes for each
1576 move depending on the situation. If easy mode is disabled (using the
1577 ``easy'' command), the program will often respond with its move
1578 immediately, saving time on its clock for use later on.
1581 writes the game moves and some statistics on search depth, nodes, and
1582 time to the file ``shogi.lst''.
1585 toggle material flag - draws on no pawns and both sides < rook.
1591 evaluates the board and shows the point score for each piece. The total
1592 score for a position is the sum of these individual piece scores.
1595 causes the program to display the principal variation and the score
1596 during the search. A score of 100 is equivalent to a 1 pawn advantage
1603 causes the program to randomize its move selection slightly.
1609 backout the last level for both sides. Equal to 2 undo's.
1612 causes the board display to be reversed. That is, the Black's pieces will
1613 now appear at the top of the board.
1616 reverse board display.
1619 saves a game to disk. The program will prompt the user for a file name.
1622 causes the program to switch places with the opponent and begin
1626 performs some speed tests for MoveList and CaptureList generation, and
1627 ScorePosition position scoring for the current board.
1630 set computer's time remaining, intended for synchronizing clocks among
1634 toggle tsume mode. In tsume mode, not all possible moves will be
1635 generated. If a king is in check, only moves that get the king out of
1636 check are generated. If the king is not in check, only moves that give
1637 check to the opponent's king are generated.
1640 undoes the last move whether it was the computer's or the human's. You
1641 may also type ``remove''. This is equivalent to two ``undo'''s
1642 (e.g. retract one move for each side).
1645 causes the computer to play as Black; if the computer is to move
1646 first the go command must be given.
1649 read an xshogi position file.
1652 save as an xshogi position file.
1655 change X window. The window around alpha/beta used to determine whether
1656 the position should be scored or just estimated. Note: this has
1657 @emph{nothing} to do with xshogi or X windows; the terms are completely
1663 @c ---------------------
1664 @c References and links.
1665 @c ---------------------
1667 @node References and links, Acknowledgements, gnushogi, Top
1668 @chapter References and links
1671 @cindex Mailing lists
1675 There are very few English-language books for people learning shogi.
1676 The two I recommend are:
1681 @cite{Shogi for Beginners, 2nd. Edition}, by John Fairbairn. This is a
1682 superb beginner's book in every way, covering all phases of the game.
1683 It was out of print for a long time, but has now been reprinted and is
1684 available either from Kiseido (@uref{http://www.labnet.or.jp/~kiseido})
1685 or from George Hodges (see below).
1688 @cite{The Art of Shogi}, by Tony Hoskings. This is one step up from the
1689 Fairbairn book. It covers a lot of ground, and is especially noteworthy
1690 for its detailed treatment of opening lines. You can order this book
1691 from Amazon.com's UK branch (@uref{http://www.amazon.co.uk}).
1695 Another book you may find is @cite{Shogi: Japan's Game of Strategy} by
1696 Trevor Leggett. This book is very elementary and is somewhat outdated,
1697 having been published first in 1966. However, it does feature a paper
1698 shogi board and punch-out pieces, so if you want a really cheap shogi
1699 set you might pick this book up. It is still in print.
1701 Two books that are no longer in print but are definitely worth getting
1702 if you find them are @cite{Guide to Shogi Openings} and @cite{Better
1703 Moves for Better Shogi}, both by Aono Teriuchi. They are published in a
1704 bilingual edition (English/Japanese) and are the only books on shogi in
1705 English written by a Japanese professional shogi player. John Fairbairn
1706 did the translation from Japanese to English.
1708 Shogi sets are available from:
1714 United Kingdom BR1 2WT
1717 George also sells equipment for all the historical shogi variants
1718 (@pxref{Shogi variants}) (except for Kyoku tai shogi) and also sells
1719 back issues of the magazine ``Shogi'' which he published for 70 issues
1720 in the late 70's to late 80's. This magazine is STRONGLY recommended;
1721 it contains more information about shogi in English than you will ever
1724 Here are some useful URLs:
1728 @item Pieter Stouten's shogi page: @uref{http://www.shogi.net}
1729 This is the main shogi-related site on the internet, with links to
1730 almost all the other sites.
1732 @item Roger Hare's shogi page: @uref{http://www.ed.ac.uk/~rjhare/shogi}
1733 This has lots of information, including full rules to most of the shogi
1736 @item Patrick Davin's Shogi Nexus: @uref{http://www.vega.or.jp/~patrick/shogi/}
1737 There's lots of cool stuff on this site; my favorite is the extensive
1738 collection of Tsume-shogi (mating) problems, both for beginners and
1739 more advanced players.
1741 @item Steve Evans' shogi page: @uref{http://www.netspace.net.au/~trout/index.html}
1742 Steve has written a program that plays almost all of the shogi variants,
1743 unfortunately it only runs on Windows :-(
1745 @item Hans Bodlaender's chess variant pages: @uref{http://www.cs.ruu.nl/~hansb/d.chessvar}
1746 This page has an almost unimaginable variety of rules for different
1747 chess variants, including many shogi variants (historical and non-historical).
1749 @item Wikipedia's shogi variant pages: @uref{http://en.wikipedia.org/wiki/Category:Shogi_variants}
1750 Those pages contain a large number of variant rules, both ancient and
1755 @c -----------------
1756 @c Acknowledgements.
1757 @c -----------------
1759 @node Acknowledgements, Bugs, References and links, Top
1760 @chapter Acknowledgements
1761 @cindex Acknowledgements
1763 I would like to thank the following people:
1768 Matthias Mutz, who originally developed GNU shogi as a spin-off of GNU
1769 chess and who very kindly let me take over the maintenance of this very
1770 interesting project.
1773 Richard Stallman and the Free Software Foundation, for creating an
1774 organization where anyone can contribute software for the common good of
1775 all, for making GNU/Linux possible, and especially for writing emacs and
1776 gcc, without which my working life would be intolerable.
1779 Georges Hodges, for starting the Shogi Association in England, without
1780 which I would probably never have heard of shogi, for supplying shogi
1781 equipment, for publishing the excellent magazine ``Shogi'' (now sadly
1782 defunct), for personally answering all my silly questions by mail, and
1783 for being the ambassador of shogi to the West.
1786 Pieter Stouten, for having the most comprehensive shogi site on the
1787 World Wide Web (@uref{http://www.shogi.net}), and for
1788 maintaining the shogi-l mailing list. Go to Pieter's web site for more
1789 information on subscribing to the list. Also thanks to everyone who
1790 contributes and has contributed to that list.
1793 Matt Casters, for testing GNU shogi. Matt and I will be working
1794 together on improving the solution engine in future versions of this
1803 @node Bugs, Index, Acknowledgements, Top
1806 The motto of GNU shogi is ``100% bug-free or you don't pay!'' :-) In
1807 the extremely unlikely case (*ahem*) that you do find a bug, please
1808 report it to the bug tracker at
1809 @uref{https://savannah.gnu.org/projects/gnushogi/}. Also, feel free
1810 to post comments, complaints, out-and-out raves, suggestions and such
1811 to one of the mailing lists at
1812 @uref{https://savannah.gnu.org/mail/?group=gnushogi}.
1825 @node Index, , Bugs, Top