From bde641976881470cbd19a7640bb37d03e3a7a434 Mon Sep 17 00:00:00 2001 From: H.G. Muller Date: Thu, 28 Feb 2013 15:41:36 +0100 Subject: [PATCH] Check in Fairy-Max web page --- CVfairy.html | 596 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 596 insertions(+), 0 deletions(-) create mode 100644 CVfairy.html diff --git a/CVfairy.html b/CVfairy.html new file mode 100644 index 0000000..b546bdd --- /dev/null +++ b/CVfairy.html @@ -0,0 +1,596 @@ + + +Fairy-Max + + + + + + +

Downloads

Fairy-Max Windows executable and source (includes ShaMax.exe and MaxQi.exe, and logo)

Pair-o-Max Windows executable (plus ini file and logo)

Looking-Glass executable for Alice Chess (includes ShaMax.exe and MaxQi.exe, and logo)

fairymax sources as tar ball for installing from source on *nix systems (includes maxqi.c)

+ +

Fairy-Max: an AI for playing user-defined Chess variants

+ +

+ +
+Introduction +
Setup +
Pieces + +
Rules +
Playing Tips +
Equipment +
Notes +
Contact +
Links to related pages would appear here. +
+
+ + + +

Introduction

+ +

+Fairy-Max is an AI, also called 'engine', for playing Chess variants. +It is free open-source software. +It was created for the purpose of empirically evaluating fairy pieces, +by allowing those to participate amongst orthodox Chess pieces +in Chess games aimed at checkmating an opponent royal piece. +It searches ahead like the FIDE-Chess engine from which it was derived +(the World's once smallest Chess program, micro-Max) +by generating moves and trying them out on the internal board. +To know how each piece type moves, micro-Max uses tables with step vectors, +and it knows which pieces are leapers and which are sliders. +In Fairy-Max, the contents of these tables is not fixed, +but is loaded from a configuration file 'fmax.ini' at the start of each game. +This allows the user to change the way pieces move +(or add pieces of his own design) without changing the program, +by altering the contents of the fmax.ini file. +Fmax.ini is a normal text file and thus can be modified with any text editor +(e.g. Notepad). +

+Fairy-Max is 'only an AI'. +This means it does not provide any graphics to display the position of the game it is playing, +but only relays the moves as text. +It is primarily designed to be run as an engine inside the WinBoard GUI, +(or its Linux counterpart XBoard), +and it communicates with this GUI in 'WinBoard protocol'. +Although there are several other GUIs that support WinBoard protocol, +they will in general not offer as much variant support as WinBoard / XBoard. +Most GUIs only support normal Chess, +but ChessGUI by Matthias Gemuh also supports 10x8 Capablanca variants. +Note that there are also many other WinBoard-compatible engines for +playing variants that can be played under WinBoard 4.3 or higher. +Some even play variants that Fairy-Max could never implement +(e.g. Xiangqi or Crazyhouse). + +

+There are however some dedicated versions of Fairy-Max that are adapted to variants +with very unique needs, +such as the Shatranj baring rule, or the confinement of pieces to certain board areas in Xiangqi. +These versions, known as ShaMax and MaxQi, respectively, are in general only useful for playing +a single Chess variant, and are included in the downloads listed at the top of this page. +There also is a derivative 'Looking Glass', which plays Alice Chess. +There also exists a special research derivative 'Pair-o-Max', +which does take into account mating potential in the late end-game. +

+ + +

Setup

+ +

+Fairy-Max can be downloaded in both Windows and Linux versions +through the links at the top of this page. +It is also included in the standard distribution of WinBoard, however, +where it is pre-installed as primary engine, and can be started from the Windows Start menu. +The Windows Fairy-Max package contains the engine executable, +the fmax.ini (which contains its own format description), +and the engine source code, all grouped inside a folder. +To install it, just extract this folder to a suitable place on your hard disk. +Recommended is to put this folder next to the one where you installed WinBoard. +WinBoard has a Load Engine dialog in its Engine menu, +which you could use to install Fairy-Max (or any other engine) by simply pointing out the exe file in a file-browse dialog. +It needs no special parameters or options. +

+Fairy-Max' hash table size can be set through WinBoard's Common Engine Options dialog, +and is responsible for almost its memory usage. +(It is rounded down to 12 times a power of two, e.g. 48MB, 96MB, 192MB) +If this does not comfortably fit in memory together with the +engine process of the opponent (if there is a computer opponent), +Fairy-Max will not run properly, and you would have to reduce the hash size. +

+For a detailed explanation of the variants that Fairy-Max can play, +see the website of chessvariants.org +

+The piece descriptions in the fmax.ini file are grouped into variants, +so that setting the engine to a certain variant (from the User Interface), +will load the group of piece descriptions for that variant. +The Fairy-Max download comes with an fmax.ini that predefines +several variants +(FIDE Chess, Capablanca Chess, Shatranj, Courier, Knightmate, Cylinder Chess), +which can serve as an example for those that want to implement their own variants. +In addition, the fmax.ini file contains definitions of the most common fairy pieces not participating in the predefined variants, +so that the user can draw on them when composing his own variants. +Although Fairy-Max supports merely 15 different piece types, +this is only a limitation to the number of different piece types that +can participate simultaneously in a single game. +In a game of another variant, all 15 pieces could move completely differently. +

+ +

Table 1: Variants pre-defined in the supplied fmax.ini

+normal +	+FIDE's good old mad-queen game +
+shatranj +	+Arabic precursor of Chess with Elephants in stead of Bishops (best played with ShaMax) +
+capablanca +	+ +10x8 variant with Archbishop and Chancellor +
+gothic +	+Patented variant similar to Capablanca, with a more exciting opening setup +
+courier +	+12x8 Medieval variant, combining Shatranj pieces with the modern Bishop +
+knightmate +	+King moves like Knight, and vice versa +
+cylinder +	+The board has no left or right edges, pieces wrap around + +
+berolina +	+8x8 variant where Pawns capture straight ahead, and move diagonally +
+super +	+Superchess, an 8x8 shuffle variant with 4 super-pieces, including Amazon +
+great +	+Great Shatranj, a 10x8 variant where all sliders are replaced by corresponding short-range pieces +
+seirawan +	+S-Chess, where a R+N and B+N compund start in hand and can be gated onto the 8x8 board +
+spartan +	+Spartan Chess, where a completely unorthodox army with two kings (the Spartans) battle the regular (Persian) FIDE army +
+makruk +	+Thai Chess, a Shatranj-like variant where Elephants are replaced by Gold Generals, and Pawns start on 3rd rank +
+falcon +	+On 10x8 with two 'falcon' pieces (multi-path lame (1,3)+(2,3) leapers) +
+- +	+Chess with Different Amies: the FIDE army, the Colorbound Cobberers, the Nutty Knights or Remarkable Rookies battle each other +
+xiangqi +	+Chinese Chess (9x10 board) with Elephants, Cannons, and a King confined to a 3x3 Palace +(only with MaxQi) +
+ +fairy +	+A catch-all variant, in which by default any piece can participate. +Fairy-Max redefines the meaning of this variant as specified by a combobox option. +

+ +

+The board size for each variant is also defined in the fmax.ini file, +and is currently limited to 12x8. +(Expansion of the number of ranks is on the to-do list.) +The default opening position is also defined in there, +but can be overruled by loading a position through the User Interface. +

+ + +

Pieces

+ +

Table 2: attributes that can be combined to define a move type

+C +	+capture +	+target square is valid if occupied by enemy piece +
+N +	+non-capture +	+target square is valid if empty +
+T +	+terminate +	+move cannot continue, even if target square is empty +
+H +	+hopper +	+move can continue if target square was occupied +
+W +	+wrap +	+treat board like left edge borders right (cylinder board) +
+M +	+multi-path +	+special move mode for Falcon in Falcon Chess +

+ +

+Apart from Pawns, orthodox Chess pieces only come in two different types: +leapers and sliders. +Leapers can only do one step of a given type, +while sliders can repeat their elementary step indefinitely, +as long as they do not encounter an obstruction (piece or board edge). +If the obstruction is an enemy piece, it can be captured, +(both by leapers and sliders), +but the move cannot continue after that even for a slider. +

+As not all fairy pieces fall in the slider or leaper category, +Fairy-Max implements two additional move types: hoppers and alternators. +Hoppers are sliders that can jump over the first obstruction in their path, +and continue from there, with possibly a different type of move. +The best known examples are the Cannon (Pao) from Chinese Chess, +and the Grasshopper. +The Pao changes its move type from 'non-capture only' to 'capture only' on hopping. +The Grasshopper changes it from 'none' to 'both' (capture and non-capture), +and in addition changes from slider to leaper. +(It is only allowed to do one step after the hop, +in contrast to the Pao, which remains a slider after hopping.) +

+Alternators are pieces that do not need to hop over anything to change +their move type, but do so spontaneously after every step they make. +This can be a change in step direction, to provide bend trajectories, +but also in capture rights. +E.g. a Xiangqi Elephant makes 2 diagonal steps in the same direction, +on the first step it is not allowed to do anything (capture or non-capture) but continue, (if the square is empty, of course), +on the second step it can both capture and non-capture (but is not allowed to continue any further, even if the square was empty). +The Xiangqi Horse is similar, but also changes direction between the first and second step. +

+The Crooked Bishop is an example of a slider that changes direction on every step. +This means both its primary and secondary step allow slider-like continuation. +After the second step it switches back to its first, +and continues alternating on every subsequent step. +For simplicity, Fairy-Max treats every slider that is not a hopper as an alternator. +In cases where this is not desired (e.g. for the Rook), +it simply 'alternates' between two identical steps. +

+To provide flexibility in implementation of fairy pieces, +the discription of the move type has to be given for each direction separately, +rather than for the piece as a whole. +This to allow mixed sliders/leapers, such as the Archbishop, +which combines the Knight (leaper) and Bishop (slider) moves. +For implementation of hoppers and alternators, +the move description (direction and type) has to be given twice +(primary and secondary move descriptor). +The method used for that in the fmax.ini file is to specify +which bits should change to make the secondary step and move rights out of the primary. +This info can be used to change them in both directions (primary -> secondary and secondary -> primary), +which is convenient for alternators. +It also means that for 'normal' pieces, where nothing changes as primary and secondary step are the same, +the secondary rights and step are all zero, and don't have to be written. +Since version 4.8S a 2-bit 'delay count' can be specified with each piece +to delay the first toggle between primary and secondary step type by 1, 2 or 3 steps, +which allows implementation of limited-range sliders of ranges upto 5. +

+ +Fairy-Max makes no assumptions to the symmetry of the piece, +meaning that all directions in which the piece moves have to be specified explicitly. +E.g. for a Rook we have to list 4 moves, for a Knight 8. +However annoying this sometimes might be, +this is necessary for allowing implementation of +asymmetric pieces such as the Crab or the Shogi Generals. +Unfortunately, Fairy-Max is not smart enough yet to realize that the different +sides play in opposite direction. +Thus asymmetric pieces (such as Pawns) have to be implemented as different +piece types for white and black. +(E.g. what is a Crab for white, will be a Barc for black, and vice versa.) +The following pieces have predefined descriptions in fmax.ini, +ready for copying to your own variants. +

Table 3: Pieces that are pre-defined in the fmax.ini that comes with the download

+ + + + + + + + + + + + + + + + + + + +

+SIMPLE LEAPERS +	+COMPOUND LEAPERS +	+LEAPER-SLIDER COMPOUND +	+SLIDERS +	+LAME LEAPERS +	+ +CYLINDER PIECES +
+Ferz +	+King / Commoner +	+Archbishop +	+Bishop +	+Elephant (Xiangqi) +	+Cylinder Bishop +
+Wazir +	+Bison +	+Chancellor +	+Rook +	+Horse (Xiangqi) +	+Cylinder Rook +
+Knight +	+ +Wildebeest +	+Caliph +	+Nightrider +	+Falcon +	+Cylinder Knight +
+Dabbaba +	+Carpenter +	+Canvasser + +	+Queen +	+SEPARATE CAPTURE +	+Cylinder Queen +
+Elephant (Alfil) +	+Kangaroo +	+Amazon +	+Crooked Bishop +	+ +FIDE Pawn +	+Cylinder Pawn +
+Camel +	+High Priestess +	+HOPPERS +	+LIMITED RANGE +	+Shatranj Pawn +	+ +
+Zebra +	+Minister +	+Grasshopper +	+Rook-3 +	+Quing +	+ +
+ +	+Crab / Barc +	+Cannon (Xiangqi) +	+Bishop-4 +	+Keen +

+ + +

Rules

+ +

+This section gives an indication of how the Chess variants are defined +in the fmax.ini file. +After a line "Game: " to indicate that a new variant description follows, +we have lines that specify the board size, +and the back rank of the array for white and black. +(Fairy-Max always assumed a close rank of Pawns directly in front of that.) +A name can be prefixed with "fairy/", meaning that it is not supported by WinBoard, +and has to be played as the catch-all vatiant "fairy". +An engine option (appearing in the GUI's Engine Settings dialog) +will in this case determine what variant is really played (identified by the part of the name after the slash). +

+The variant name can be followed by a # and extra information. +In such a case Fairy-Max will send a 'setup' command to the GUI to inform it of the default opening +position for the variant, possibly accompanied by the info behind the #, +which designates the one-letter piece ID with which the GUI should represent the various pieces. +After the three initial lines follow the descriptions of all participating pieces, +one line per piece. +

+For each piece, we have to give the letter by which it is represented +when feeding a position to the engine, +and the value the engine should attach to it in play. +(So beware, Fairy-Max is not smart enough to figure this out by itself. +If you tell it an immensely powerful piece like a Queen is only worth half a Pawn, +it will happily trade it for one!) +Then follows on the same line a list of move descriptors, +one for each direction the piece moves in. +A move description consists of an elementary board step, +and a number that specifies the move attributes, +i.e. what the piece is allowed to do in this direction +(if it can capture and/or non-capture, if it is leaper or slider, +if it can hop over an obstacle or not, +if it respects the board edges or wraps around.) +The exact way the step vectors and attributes are encoded +is specified in comment lines contained in the fmax.ini, +as it might still be subject to change in future versions. +

+The first two pieces specified are by definition the white and black Pawns. +That means that Fairy-Max will let them promote if they reach the last rank. +Fairy-Max does not think about under-promotion, +but always promotes to 'Queen', i.e. the 7th piece specified, however that may move. +Except when piece number 7 only appears in the initial setup for white, +and a piece with number 9 occurs in the initial setup for black, +in which case black would always promote to piece 9 +(to allow variants with different armies). +

+Any piece with a negative value is considered royal. +Fairy-Max makes a difference between value -1 and other negative values, though: +-1 indicates absolute royalty, i.e. loss of any piece of this type means loss of the game. +Other values indicate only loss of the last royal piece result in loss of the game, +and any spare ones should be treated as if they are worth the absolute value of the given number. +This allows for variants with 'delocalized royalty', such as Spartan Chess. +

+ + +

Notes

+There are many things that Fairy-Max cannot do; it was never meant to be a general game-playing system like Zillions of Games. +Amongst the impossibilities are piece drops, (as in Crazyhouse or Shogi), +pieces for which the moves are dependent on their location on the board +(as in Xiangqi, but MaxQi handles this particular case). +and pieces whose moving exerts side effects on other squares that their old and new location +(with the exception of castling and e.p capture). +For some pieces the move is simply too complicated to fit within the Fairy-Max move-type classification system (e.g. Rose, Griffon). +

+Only boards with 8 ranks are currently implemented. + +

+The current version of Fairy-Max implements e.p. capture in such a way that it also correctly handles Berolina Pawns, +and allows castling with any corner piece. +

+ + +

Playing Tips

+Positional evaluation in Fairy-Max is fairly primitive: +a piece either is drawn towards the center, or not. +If you want a piece to be drawn to the center, +you should indicate it by a lower-case letter. +Pawns do get a large positional bonus when they reach 6th or 7th rank, +of 64 and 128 units ('centiPawn' in FIDE Chess), respectively. +This assumes that the piece to which the Pawns will promote is of decisive value, +so the opponent will have to sacrifice a piece to stop the promotion. +Unfortunately, this does not work very well in Shatranj and Courier Chess, +where Pawns promote to the worthless Ferz. +Recent versions of Faiy-Max divide this bonus by 8 in cases where a "Queen" +(the piece to which Pawns promote by default) +is worth less than 250 centi-Pawn, to repair this problem. +Nevertheless, the strategy of Fairy-Max is tailored too much to normal Chess, with normal Pawns +to be a really good Shatranj or Courier player. +

+ + +

Equipment

+ +Fairy-Max runs on a PC under any Windows operating system. +The memory demand is determined by the size of its hash table, +which by default is 96M. +It would still run with a smaller hash table, +but the larger the hash table, the better its play. +Running with a hash table smaller than 6MB is not recommended. +Recently also versions that can run on other platforms, such as Linux, were released. +

+ + +

Contact

+Questions about Fairy-Max can be posted as comments to the Fairy-Max page +on the chessvariants website, +which are checked regularly by H.G. Muller, +and of which this page is an adapted version. + + +

Written by H.G. Muller. +

WWW page created: July 8, 2008. Last updated: February 28, 2013. + + + + + + -- 1.7.0.4