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Xiangqi (象棋): Chinese Chess. Links and rules for Xiangqi (Chinese Chess). (9x10, Cells: 90) (Recognized!)[All Comments] [Add Comment or Rating]
M Winther wrote on 2011-01-21 UTC
Is the repetition rule really valid for *all* moves, and not only for consecutive repetitions? I didn't know that, because then the notion of 'chase' loses its meaning. Anyway, I don't think it's necessary to check other repetitions than the consecutive. This is the form of repetition that causes problems, and non-consecutive three-move repetitions are nearly non-existent.

H. G. Muller wrote on 2011-01-21 UTC
Well, Xiangqi servers are infamous for poor implementation of the rules (not surprisingly, when these rules are next to infinitely complex).

One of my points was that it is not just for moving back and forth, but for any repeat, no matter how far in the past. This in definite disagreement with what you said.

But your idea of providing a warning is a good one, I think. Except that I think it would be better to give the warning already on the first repetition, and terminate the game (with unknown score) on the third repetition. Even if the moves were with a King or Pawn (because it is still a draw then, and only if the King or Pawn did not discover threats by other pieces, which is again complex to test.)  The warning could be something like:

WARNING! You are repeating a previous position. If both of you will keep this up, the game will be declared lost to the side which is forcing the other to repeat (by checking, or perpetually threatening a favorable capture of the same piece).

M Winther wrote on 2011-01-21 UTC
H.G., I think my summary is good enough, because it is only a matter of putting an end to the repetition process. Whether the third repetition should result in a draw or a win, needn't be evaluated by the preset. The preset merely prevents the third repetition, if it isn't made by a king, or a soldier. It's a clever solution. The players can decide to continue, or the losing player may give up instead of continuing the repetition, or the players could agree on a draw, depending on what the rules say. I have played on the Xiangqi sites, and they brutally prevent three-fold repetition, or judge it as a loss to the repeating party. 

H. G. Muller wrote on 2011-01-21 UTC
I don't think you give a correct summary of those Xiangi rules. At least, not for the rules I know ('Asia rules'). For one, the condition is for causing any repeated position, not just consecutive. (So just like in FIDE Chess.) The difference with FIDE rules is that a 3rd repeat is not automatically draw, but can also be judged as win or loss. A side that is somehow forcing the repetition will be ruled to lose, where forcing by checking is considered a worse offense than forcing by merely attacking a superior or unprotected non-royal piece ('chasing'). So that if both are continuously forcing each other, the checking side loses. To be counted as a perpetual check or chase, every move of the repeat loop must be a forcing move threatening the same piece; if there is only one 'quiet' move (even a mate-in-1 threat) in the loop, or a move that only threatens another piece, (even if that is a check amongst chases), it is not considered perpetual check or chase.

The exact rules for which moves are to beconsidered forcing, and which not, are so complex that it requires a sizable AI to implement them. (See )

China mainland rules seem to be even more complex (even mate threats counting as forcing), and I have never been able to find an English description of them.

M Winther wrote on 2011-01-21 UTC
Fergus, one very important rule is not implemented in your Xiangqi preset. Players are not allowed to move back and forth so that the position is repeated three times (immediately after one another, not overall, as in Fide-chess). If there were no such prevention of repetition, then Xiangqi would be much more drawish. 

Would it be possible to implement this rule so that the player who tries to repeat the position for the third time is prevented from doing this move? Exceptions are if he makes the move with a soldier, or with the general, when he can continue play.

There are cases when players are allowed to go back and forth, when they both go back and forth between different squares, but in this case the players can agree on a draw, so your prevention of the third move only serves as a reminder that it is a draw.

Fergus Duniho wrote on 2010-10-14 UTC

Here's my new video on how to play Chinese Chess:

Anonymous wrote on 2010-07-16 UTC
'Junk Kay'

Actually, it's pronounced without the 'k' sound in the first word. So
you might want to revise the sentence to read 'Jun Kay' (although it
sounds more correct pheonetically as 'Jerng Kay'.)

Liyuan wrote on 2010-06-10 UTCExcellent ★★★★★
This is very good introduction to ÏóÆå¡£Thank you!

I have one suggestion here about the meaning of ½«. it is not 'will' or
'going to' here, although it does have such meanings. The character by
itself means something similar to 'to lead' as a verb, or it could mean
'leader/general' as an abbreviation for ½«Áì. It is also a military rank
nowadays. ½« is pronounced with the fourth tone here whereas when it's
used to express the meaning of 'will' or 'going to', it's pronounced
with the third tone.

Flowerman wrote on 2010-03-14 UTC
Do someone know something about ancient Chinese game 'Semedo'? I read that it's early variant of Xiang-qi, but i don't know exact rules and can't find it.

Flowerman wrote on 2010-03-09 UTCGood ★★★★
I have question: what are early variants of Xian-qi?

Fergus Duniho wrote on 2010-02-25 UTC
Skye, Have you noticed the column of links on the right side? It provides links to sites where you can play against other people. Determining whether other players are at your own level is something you'll have to determine on your own. If you use Game Courier, Game Courier's rating system can help you identify who plays at your level once you have played enough games to have a meaningful rating. This page describes the rules, and if that isn't sufficient for helping you learn how to play, there are links on the right side to other sites describing how to play, as well as to software you can use to learn and play the game.

Skye wrote on 2010-02-25 UTC
We need a link to where we can find someplace to both learn how to play, play with others and play with others at our same level.

H. G. Muller wrote on 2009-10-31 UTC
The defensive pieces required a new approach in material evaluation, in my Xiangqi engine HaQiKi D. Rather than having a fixed value, their value is strongly dependent on the attacking material the opponent has. To implement that I use a material table that is indexed by the number of attacking pieces of each type for one side, and the number of defensive pieces of the other side.

In my simpler engine MaxQi (a dedicated version of Fairy-Max that can only play Xiangqi) I just use fixed piece values, and then itregularly happens that it converts its entire advantage to defensive pieces, thinking it is 800 centi-Pawn ahead, while in fact it has zero winning chance...

Larry Smith wrote on 2009-10-31 UTC
An aspect of Chinese Chess is that certain pieces are primarily defensive(Elephants and Ministers). Also that the both players need to maintain offensive pieces to prosecute the game.

These values can tax a simple depth-search program. Demanding at least a few extra computational considerations.

Fergus Duniho wrote on 2009-10-30 UTC
I agree with the reasoning for why Chess has a greater state-space complexity and a greater game-tree complexity than Chinese Chess. Having programmed the rules of both games, I will add some thoughts on computational complexity. This is primarily a factor of the number of possible moves available to a player each turn. Since Chess pieces all have greater powers of movement than their Chinese counterparts, a computer playing Chess may have to make more calculations to evaluate a move to the same depth. The main factors in favor of greater computational complexity for Chinese Chess are the larger board, the presence of Cannons, and the rule against opposing Generals. The larger board affects mainly Cannon and Chariot moves, since other pieces have limited ranges, and the opposing Generals rules. A Cannon is less computationally complex than a Rook, because it normally has fewer spaces it can move to. A Bishop is also less computationally complex than a Rook. Although the code for a Bishop move will be nearly identical to the code for a Rook move, it has as many possible moves as a Rook only from some positions. A centered Bishop has 14 possible moves on an empty board, the same as a Rook, but as a Bishop moves toward the edge, it has fewer possible moves on an empty board. I haven't done the math to tell which is more complex, but I suspect the Cannon is. Although a Horse sometimes has fewer moves than a Knight, it adds the computational complexity that comes from being able to pin pieces. A horse move can affect the possible moves of the opponent in ways that a Knight move cannot. The main source of greater complexity for Chess comes from the greater powers of the King and Queen, the ability of Pawns to promote, and the rules concerning castling and en passant. A Queen may have as much complexity as two Cannons, maybe more. A King normally has more moves than a General, and the opposing Generals rule only adds one more move to consider. Based on these considerations, I suspect that Chess is more computationally complex, but I have not done the math that a proof would require.

Rich Hutnik wrote on 2009-08-31 UTC
Not sure triviality or not is an issue here. What may be beneficial is if the CV site had a place to reference other games that aren't in the same family as chess. I do believe the Courier system does enable people to play Go on it (and checkers also).

Larry Smith wrote on 2009-08-31 UTC
Checkers might be considered trivial, while Go is quite complex. Though a simple reference link would suffice.

Rich Hutnik wrote on 2009-08-31 UTC
I would also disagree with Go having an entry on here. It isn't part of the same family of abstract strategy games Chess is.

John Smith wrote on 2009-08-31 UTC
I disagree. We shouldn't have Checkers listed here for the same reason.

Larry Smith wrote on 2009-08-31 UTC
GD, check out:

Also check out:


Go should really have a page here at TCVP. Particularly since there are
several variants which are based upon this game and its equipment.

George Duke wrote on 2009-08-30 UTC
'Chess&X.player' cites the state-space complexity of 8x8 chess at around 10^50. Last year 'Singh' claims there are this following many states of the universe in its entirety:
The first comment says ''silly'' but the probably bleak future indicated in the other two of Singh is not so silly.  'Chess&X.player's computational complexity in the comment here 29.August.2009, actually allowing variantly larger boards etc., is open-ended and he does not try to give numbers. And he ends up in the comment, admitting he is excellent OrthoChess player, like some remaining couple of CVPage stand-patters, talking as if OrthoChess is some one given thing to stay unchanged forever more. Hey, thanks for neat statisitics and please consider becoming a member for something different to look at for a change. Now we know there's more to life than Knife-Knight, Fork-Bishop, and Spood-fed-Rook. 'Chess&X.player' concludes that Go outdoes them all, and haven't we heard that immortal truth before?! But never frequently enough.

Joe Joyce wrote on 2009-08-30 UTC
Thanks for the very thoughtful comment comparing chess and xiangqi. I've already gotten one private message which said just that. A very interesting conclusion, and more deeply reasoned than many other comparisons of the two games which have come up with various conclusions.

ChessAndXiangqiPlaye wrote on 2009-08-29 UTCExcellent ★★★★★
I've been thinking about the question of whether Chess or Xiangqi (Chinese
Chess) is strictly speaking the more complex game when viewed from the
perspective of complexity theory.

For more information on Chess and Xiangqi, see



Using the ideas of complexity theory, the complexity of Chess and Xiangqi
can be estimated and calculated quantitatively. In general, there are 3
different kinds of complexity a deterministic board game like Chess or
Xiangqi may have:

1 State-space Complexity: the maximum number of possible positions in the
game. It is also possible to calculate an upper bound for state-space
complexity which includes illegal positions as well. The upper bound is
generally speaking much easier to calculate than the exact value, which is
often only given as an accurate estimation.

It is generally calculated that the state-space complexity of Chess is
around 10^50 (10 to the power of 50, or 1 with 50 zeros after it, or one
hundred trillion trillion trillion trillion different positions), while the
state-space complexity of Xiangqi is around 10^48, 100 times less than that
of Chess. This is because despite a larger board (9 times 10 vs. 8 times
8), Xiangqi pieces are generally speaking less powerful than their Chess
equivalents and for many pieces the space over which it can potentially
move is severely restricted. In Chess, the King, Queen, Rook and Knight can
potentially move to every square on the board, the Pawn can potentially
reach more than 6/8th of all the squares (though unlikely to move that much
in a real game), and even the Bishop can reach half of all the squares. In
Xiangqi the General can only stay inside the Palace and move to 9 different
intersections, the Advisor can only move to 5 different intersections and
the Elephant only to 7 different intersections.

Another factor is that the Xiangqi board, having 9 files instead of
Chess's 8, is symmetrical in the left-right direction. This means the left
and right hand sides in Xiangqi are essentially the same, so different
board positions may just be a trivial reflection of the other. This
decreases the effective state-space complexity of Xiangqi by a factor of 2.
In Chess on the other hand, the Kingside and the Queenside are not just a
trivial reflection of each other since the distance the King has to the
edge of the board is different for the left and right hand sides.

Therefore despite having 90 intersections on the Xiangqi board vs. only 64
squares for Chess, the total number of possible positions is around 100
times more in Chess than Xiangqi, 10^50 vs. 10^48.

2 Game-tree Complexity: roughly speaking this is the total number of
possible games one can potentially play with a particular version of board
game. This is different from state-space complexity and the value is
generally speaking far larger because state-space complexity only takes
space and position into account, while game-tree complexity analyses the
actual moves in a game and hence also puts time into account. Generally
speaking, there are many different ways, in terms of playing the game, to
reach a particular position on the board. For instance, the opening
position on the chess board with Ng1-f3 and e2-e4 (moving the King's
Knight and King's Pawn out) can be reached via two different
'game-trees': Nf3 first or e4 first, and the number of possible
game-trees for a given board position increases dramatically as one
progresses into the game and the position becomes much more complex.

Generally it is estimated that the total number of possible games in Chess
is around 10^123 (or 1 with 123 zeros after it), while for Xiangqi it is
10^150, which is 100 million billion times more than Chess. For comparison,
consider that the total number of atoms in the observable universe is only
around 10^80.

There are far more possible games in Xiangqi since it is played on a
larger board (90 instead of 64 spaces), and generally a game of Xiangqi
lasts for more moves than a game of Chess. However, given that the Xiangqi
board is left-right symmetrical and therefore left-hand side play is
identical to right-hand side play, and that since Xiangqi pieces are
generally less powerful and the General is restricted to within the Palace,
the larger number of possible games in the purely technical sense becomes
relatively trivial by the endgame stage, since real play is likely to be
always focused around the General's Palace, and different moves elsewhere
on the board essentially converges to the same kind of endgames. In other
words, whereas in the earlier phase of the game the game-tree of possible
moves branches out, by the endgame in Xiangqi they begin to converge into
one-another, and Xiangqi games generally end in relatively similar
positions (major pieces and pawns around the General's Palace and a
relatively exposed General).

In Chess game-trees also tend to converge more by the endgame but since
the King can move to anywhere on the board and there is the possibility of
pawn promotion, the game converges to a significantly smaller extent than
Xiangqi. Also the approximate estimation for the game-tree complexity of
Chess does not take into account the re-divergence of the game-tree if
enough pawns are promoted into pieces in the endgame. Although in real play
this tends to be an unlikely scenario, in technical calculations of game
complexity this factor should be included. In addition, when the game-tree
complexity of Chess is calculated, unlikely endgame scenarios, such as the
game dragging on unnecessarily for dozens of extra moves that are in
practice trivial, are also included.

Therefore effectively speaking despite the technically higher game-tree
complexity of Xiangqi, I think Chess is actually the more complex game of
the two.

3 Computational Complexity: a third way to calculate game complexity is to
consider how much computational steps are required to play a Chess or
Xiangqi game by a Chess or Xiangqi engine/computer as the actual size of
the game increases in space. E.g. if the Chess board size doubles, how much
more computational power is required? In this both Chess and Xiangqi are
very similar in that computational difficulty increases exponentially (in
terms of the number of calculational steps required to play the game) with
board size. Thus both games are said to be inside the complexity class
called EXPTIME (stands for 'exponential time').

Personally despite being an ethnic Chinese and proud of Chinese culture in
general, I think Chess is a better game than Xiangqi and I'm a better
player in Chess than in Xiangqi. Though of course the Chinese game of
Weiqi/Go is far more complex than either of these games mentioned here.

H. G. Muller wrote on 2009-02-06 UTC
I just produced a special Xiangqi version of my general variant engine Fairy-Max. Xiangqi is sufficiently different, because of its subdivided board, deviating promotion, stalemate an repetition rules, to warrant a separate engine, rather a further generalization of Fairy-Max.

The engine is called MaxQi, and is availabe as source code and Windows excutable from my website (download link ). It uses WinBoard protocol to communicate its moves, and so can be run under WinBoard 4.3 ('WinBoard_F'). Other WB engines are HoiXinagqi and TJxiangqi. MaxQi is definitely a lot stronger than HoiXiangqi; I have not had it play many games against TJxiangqi yet, but I expect MaxQi to be weaker than that.

Charles Gilman wrote on 2009-02-04 UTCExcellent ★★★★★
The illustrations of sets do a lot to put this game into its historic and geographic context.

Has anyone else noticed that the Bare Facing rule is an example, many centuries before the rise of music downloads, of a restriction on file sharing?

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