* Documentation:: Getting Documentation
* CGoban:: Running GNU Go with CGoban
* Other Clients:: Other Clients
* Ascii:: The Ascii Interface
* Emacs:: GNU Go mode in Emacs
* GMP and GTP:: The Go Modem Protocol and Go Text Protocol
* Tournaments:: Computer Tournaments
* SGF Support:: The Smart Game Format
* Invoking GNU Go:: Command line options
@section Getting Documentation
You can obtain a printed copy of the manual by running @command{make
gnugo.pdf} in the @file{doc/}directory, then printing the resulting file. The
manual contains a great deal of information about the algorithms of GNU Go.
On platforms supporting info documentation, you can usually
install the manual by executing `make install' (running as
root) from the @file{doc/} directory. This will create a file
called @file{gnugo.info} (and a few others) and copy them into
a system directory such as @file{/usr/local/share/info}. You
may then add them to your info directory tree with the command
@command{install-info --info-file=[path to gnugo.info] --info-dir=[path to dir]}.
The info documentation can be read conveniently from within Emacs by executing
the command @command{Control-h i}.
Documentation in @file{doc/} consists of a man page @file{gnugo.6}, the
info files @file{gnugo.info}, @file{gnugo.info-1}, ... and the
Texinfo files from which the info files are built. The Texinfo
documentation contains this User's Guide and extensive information
about the algorithms of GNU Go, for developers.
If you want a typeset copy of the Texinfo documentation, you can
@command{make gnugo.dvi}, @command{make gnugo.ps}, or @command{make
gnugo.pdf} in the @file{doc/} directory. (@command{make gnugo.pdf} only
works after you have converted all .eps-files in the doc/ directory to
.pdf files, e.g. with the utility epstopdf.)
You can make an HTML version with the command @command{makeinfo --html
gnugo.texi}. If you have @command{texi2html}, better HTML documentation
may be obtained by @command{make gnugo.html} in the @file{doc/}
User documentation can be obtained by running @command{gnugo --help}
or @command{man gnugo} from any terminal, or from the Texinfo
Documentation for developers is in the Texinfo documentation, and in comments
throughout the source. Contact us at @email{gnugo@@gnu.org} if you are
interested in helping to develop this program.
@section Running GNU Go via CGoban
There are two different programs called CGoban, both written by
William Shubert. In this documentation, CGoban means CGoban 1.x,
the older program. You should get a copy with version number 1.12
CGoban is an extremely nice way to run GNU Go. CGoban provides a
beautiful graphic user interface under X Window System.
Start CGoban. When the CGoban Control panel comes up, select ``Go
Modem''. You will get the Go Modem Protocol Setup. Choose one (or
both) of the players to be ``Program,'' and fill out the box with the
path to @file{gnugo}. After clicking OK, you get the Game Setup
window. Choose ``Rules Set'' to be Japanese (otherwise handicaps
won't work). Set the board size and handicap if you want.
If you want to play with a komi, you should bear in mind that
the GMP does not have any provision for communicating the komi.
Because of this misfeature, unless you set the komi at the command
line GNU Go will have to guess it. It assumes the komi is 5.5 for
even games, 0.5 for handicap games. If this is not what you want,
you can specify the komi at the command line with the
@option{--komi} option, in the Go Modem Protocol Setup window.
You have to set the komi again in the Game Setup window, which
Click OK and you are ready to go.
In the Go Modem Protocol Setup window, when you specify the path to
GNU Go, you can give it command line options, such as @option{--quiet} to
suppress most messages. Since the Go Modem Protocol preempts standard
I/O other messages are sent to stderr, even if they are not error
messages. These will appear in the terminal from which you started
In addition to CGoban (@pxref{CGoban}) there are a number of
other good clients that are capable of running GNU Go. Here
are the ones that we are aware of that are Free Software. This
list is part of a larger list of free Go programs that is maintained
at @url{http://www.gnu.org/software/gnugo/free_go_software.html}.
@item Quarry (@url{http://home.gna.org/quarry/}) is a GPL'd
client that supports GTP. Works under GNU/Linux and requires
GTK+ 2.x and librsvg 2.5. Supports GNU Go as well as other
engines. Can play not only Go, but also a few other board
@item qGo (@url{http://sourceforge.net/projects/qgo/}) is a
full featured Client for playing on the servers, SGF viewing/editing,
and GNU Go client written in C++ for GNU/Linux, Windows and Mac OS X.
Can play One Color Go. Licensed GPL and QPL.
@item ccGo (@url{http://ccdw.org/~cjj/prog/ccgo/}) is a GPL'd client
written in C++ capable of playing with GNU Go, or on IGS.
@item RubyGo (@url{http://rubygo.rubyforge.org/}) is a GPL'd
client by J.-F. Menon for IGS written in the scripting language Ruby.
RubyGo is capable of playing with GNU Go using the GTP.
@item Dingoui (@url{http://dingoui.sourceforge.net/}) is a free
GMP client written in GTK+ which can run GNU Go.
@item Jago (@url{http://www.rene-grothmann.de/jago/})
is a GPL'd Java client which works for both Microsoft Windows
@item Sente Software's FreeGoban
(@url{http://www.sente.ch/software/goban/freegoban.html}) is a
well-liked user interface for GNU Go (and potentially other
programs) distributed under the GPL.
@item Mac GNU Go (@url{http://www1.u-netsurf.ne.jp/~future/HTML/macgnugo.html}) is a front end for GNU Go 3.2 with both
English and Japanese versions. License is GPL.
@item Quickiego (@url{http://www.geocities.com/secretmojo/QuickieGo/})
is a Mac interface to GNU Go 2.6.
@item Gogui (@url{http://sourceforge.net/projects/gogui/}) from
Markus Enzenberger is a Java workbench that allows you to play
with a gtp (@url{http://www.lysator.liu.se/~gunnar/gtp})
engine such as GNU Go. Licence is GPL. Gogui does not
support gmp or play on servers but is potentially very useful for programmers
working on GNU Go or other engines.
Even if you do not have any client program, you can play with GNU Go
using its default Ascii interface. Simply type @command{gnugo}
at the command line, and GNU Go will draw a board. Typing
@command{help} will give a list of options. At the end of the
game, pass twice, and GNU Go will prompt you through the
counting. You and GNU Go must agree on the dead groups---you
can toggle the status of groups to be removed, and when you
are done, GNU Go will report the score.
You can save the game at any point using the @command{save @var{filename}}
command. You can reload the game from the resulting SGF file with
the command @command{gnugo -l @var{filename} --mode ascii}. Reloading
games is not supported when playing with CGoban. However you can
use CGoban to save a file, then reload it in ascii mode.
You may play games with a time limit against GNU Go in
ascii mode. For this, the Canadian time control system
is used. (See @uref{http://en.wikipedia.org/wiki/Byoyomi}
and @uref{http://senseis.xmp.net/?CanadianByoyomi}.)
That is, you have a main time to be followed by byo-yomi
periods. After the main time is exhausted you have a certain
number of moves to be made in a certain number of seconds.
(@pxref{Invoking GNU Go})
@section GNU Go mode in Emacs
You can run GNU Go from Emacs. This has the advantage
that you place the stones using the cursor arrow keys
or with the mouse, and you can have a nice graphical display of the board
You will need the file @file{interface/gnugo.el}. There is
a version of this distributed with GNU Go but it only
works with Emacs 21. Most Emacsen are Emacs 22 however.
Therefore you should get the latest version of
gnugo.el by Thien-Thi Nguyen, which you can find at
@uref{http://www.gnuvola.org/software/j/gnugo/} or
@uref{http://www.emacswiki.org/emacs/gnugo.el}.
You will also need some xpm files for the graphical
display. You can either use those distributed by
Thien-Thi Nguyen (at the first URL above) or those
distributed with GNU Go, either the file
@file{interface/gnugo-xpms.el} or (for high resolution
displays) @file{interface/gnugo-big-xpms.el}.
Load the file @file{interface/gnugo.el} and
@file{interface/gnugo-xpms.el}. You may do this using the
Emacs @command{M-x load-file} command.
When you start a game with @command{M-x gnugo},
you will first see an ascii board. However typing `i'
toggles a graphical board display which is very nice.
This is a pleasant way to play GNU Go. You may get
help by typing @command{C-x m}.
@section The Go Modem Protocol and Go Text Protocol
@cindex The Go Modem Protocol and Go Text Protocol
The Go Modem Protocol (GMP) was developed by Bruce Wilcox with input from
David Fotland, Anders Kierulf and others, according to the history in
@url{http://www.britgo.org/tech/gmp.html}.
Any Go program @emph{should} support this protocol since it is a
standard. Since CGoban supports this protocol, the user interface for
any Go program can be done entirely through CGoban. The programmer can
concentrate on the real issues without worrying about drawing stones,
resizing the board and other distracting issues.
GNU Go 3.0 introduced a new protocol, the Go Text Protocol
(@pxref{GTP}) which we hope can serve the functions currently
used by the GMP. The GTP is becoming increasingly adopted by
other programs as a method of interprocess communication,
both by computer programs and by clients. Still the GMP is
widely used in tournaments.
@section Computer Go Tournaments
Computer Tournaments currently use the Go Modem Protocol.
The current method followed in such tournaments is to connect
the serial ports of the two computers by a ``null modem'' cable.
If you are running GNU/Linux it is convenient to use CGoban.
If your program is black, set it up in the Go Modem Protocol
Setup window as usual. For White, select ``Device'' and set
the device to @file{/dev/cua0} if your serial port is COM1
and @file{/dev/cua1} if the port is COM2.
@section Smart Game Format
@cindex SGF (Smart Game Format)
@cindex Smart Game Format
The Smart Game Format (SGF), is the standard format for storing Go games.
GNU Go supports both reading and writing SGF files. The SGF specification
@url{http://www.red-bean.com/sgf/}
@section Invoking GNU Go: Command line options
@cindex command line options
@subsection Some basic options
@item @option{--help}, @option{-h}
Print a help message describing the options. This will also
tell you the defaults of various parameters, most importantly
the level and cache size. The default values of these
parameters can be set before compiling by @command{configure}.
If you forget the defaults you can find out using @option{--help}.
@item @option{--boardsize @var{size}}
@item @option{--komi @var{num}}
@item @option{--level @var{level}}
GNU Go can play with different strengths and speeds. Level 10
is the default. Decreasing the level will make GNU Go faster
but less accurate in its reading.
@item @option{--quiet}, @option{--silent}
Don't print copyright and other messages. Messages specifically
requested by other command line options, such as @option{--trace},
@item @option{-l}, @option{--infile @var{filename}}
Load the named SGF file. GNU Go will generate a move for
the player who is about to move. If you want to override this
and generate a move for the other player you may add the
option @option{--color @var{<color>}} where @var{<color>} is
@code{black} or @code{white}.
@item @option{-L}, @option{--until @var{move}}
Stop loading just before the indicated move is played. @var{move} can
be either the move number or location.
@item @option{-o}, @option{--outfile @var{filename}}
@item @option{-O}, @option{--output-flags @var{flags}}
Add useful information to the sgf file. Flags can be 'd', 'v' or
both (i.e. 'dv'). If 'd' is specified, dead and critical dragons
are marked in the sgf file. If 'v' is specified, move valuations
around the board are indicated.
@item @option{--mode @var{mode}}
Force the playing mode ('ascii', 'emacs,' 'gmp' or 'gtp'). The default is
ASCII, but if no terminal is detected GMP (Go Modem Protocol) will be
assumed. In practice this is usually what you want, so you may never
@item @option{--resign-allowed}
GNU Go will resign games if this option is enabled. This is the default unless
you build the engine with the configure option
@option{--disable-resignation-allowed}. Unfortunately
the Go Modem Protocol has no provision for passing a resignation,
so this option has no effect in GMP mode.
@item @option{--never-resign}
GNU Go will not resign games.
@item @option{--resign-allowed}
GNU Go will resign lost games. This is the default.
@subsection Monte Carlo Options
GNU Go can play Monte Carlo Go on a 9x9 board. (Not
available for larger boards.) It makes quite a strong
engine. Here are the command line options.
@item @option{--monte-carlo}
Use Monte Carlo move generation (9x9 or smaller).
@item @option{--mc-games-per-level <number>}
Number of Monte Carlo simulations per level. Default 8000.
Thus at level 10, GNU Go simulates 80,000 games in order
@item @option{--mc-list-patterns}
list names of builtin Monte Carlo patterns
@item @option{--mc-patterns <name>}
Choose a built in Monte Carlo pattern database. The
argument can be @file{mc_mogo_classic}, @file{mc_montegnu_classic}
@item @option{--mc-load-patterns <filename>}
read Monte Carlo patterns from file
@subsection Other general options
@item @option{-M}, @option{--cache-size @var{megs}}
Memory in megabytes used for caching of read results. The default size
is 8 unless you configure gnugo with the command @command{configure
--enable-cache-size=@var{size}} before compiling to make @var{size} the
default (@pxref{Installation}). GNU Go stores results of its reading
calculations in a hash table (@pxref{Hashing}). If the hash table is
filled, it is emptied and the reading continues, but some reading may
have to be repeated that was done earlier, so a larger cache size will
make GNU Go run faster, provided the cache is not so large that swapping
occurs. Swapping may be detected on GNU/Linux machines using the program
@command{top}. However, if you have ample memory or if performance seems
to be a problem you may want to increase the size of the cache using
@item @option{--chinese-rules}
Use Chinese rules. This means that the Chinese or Area Counting is
followed. It may affect the score of the game by one point in even
games, more if there is a handicap (since in Chinese Counting the
handicap stones count for Black) or if either player passes during the
@item @option{--japanese-rules}
Use Japanese Rules. This is the default unless you specify
@option{--enable-chinese-rules} as a configure option.
@item @option{--play-out-aftermath}
@item @option{--capture-all-dead}
These options cause GNU Go to play out moves that are usually left
unplayed after the end of the game. Such moves lose points under
Japanese rules but not Chinese rules. With
@option{--play-out-aftermath}, GNU Go may play inside its
territory in order to reach a position where it considers every
group demonstrably alive or dead. The option
@option{--capture-all-dead} causes GNU Go to play inside its own
territory to remove dead stones.
@item @option{--forbid-suicide}
Do not allow suicide moves (playing a stone so that it ends up without
liberties and is therefore immediately removed). This is the default.
@item @option{--allow-suicide}
Allow suicide moves, except single-stone suicide. The latter would not
change the board at all and pass should be used instead.
@item @option{--allow-all-suicide}
Allow suicide moves, including single-stone suicide. This is only
interesting in exceptional cases. Normally the
@option{--allow-suicide} option should be used instead.
@item @option{--simple-ko}
Do not allow an immediate recapture of a ko so that the previous
position is recreated. Repetition of earlier positions than that are
allowed. This is default.
Allow all kinds of board repetition.
@item @option{--positional-superko}
Forbid repetition of any earlier board position. This only applies to
moves on the board; passing is always allowed.
@item @option{--situational-superko}
Forbid repetition of any earlier board position with the same player
to move. This only applies to moves on the board; passing is always
@item @option{--copyright}: Display the copyright notice
@item @option{--version} or @option{-v}: Print the version number
@item @option{--printsgf @var{filename}}:
Create an SGF file containing a diagram of the board. Useful with
@option{-l} and @option{-L} to create a diagram of the board from
another sgf file. Illegal moves are indicated with the private
@code{IL} property. This property is not used in the FF4 SGF
specification, so we are free to preempt it.
Print which experimental configure options were compiled into the program
@item @option{--orientation @var{n}}
Combine with @option{-l}. The Go board can be oriented in 8 different
ways, counting reflections and rotations of the position; this option
selects an orientation (default 0). The parameter @samp{n} is an integer
@subsection Other options affecting strength and speed
@item @option{--level @var{amount}}
The higher the level, the deeper GNU Go reads. Level 10 is the default.
If GNU Go plays too slowly on your machine, you may want to decrease it.
This single parameter @option{--level} is the best way of
choosing whether to play stronger or faster. It controls
a host of other parameters which may themselves be set
individually at the command line. The default values of
these parameters may be found by running @command{gnugo --help}.
Unless you are working on the program you probably don't
need the remaining options in this category. Instead,
just adjust the single variable @option{--level}. The
following options are of use to developers tuning the
program for performance and accuracy. For completeness,
@item @option{-D}, @option{--depth @var{depth}}
Deep reading cutoff. When reading beyond this depth (default 16) GNU
Go assumes that any string which can obtain 3 liberties is alive. Thus
GNU Go can read ladders to an arbitrary depth, but will miss other
types of capturing moves.
@item @option{-B}, @option{--backfill-depth @var{depth}}
Deep reading cutoff. Beyond this depth (default 12) GNU Go will no
longer try backfilling moves in its reading.
@item @option{--backfill2-depth @var{depth}}
Another depth controlling how deeply GNU Go looks for backfilling
moves. The moves tried below @code{backfill2_depth} are generally more obscure
and time intensive than those controlled by @code{backfill_depth}, so this
parameter has a lower default.
@item @option{-F}, @option{--fourlib-depth @var{depth}}
Deep reading cutoff. When reading beyond this depth (default 7) GNU
Go assumes that any string which can obtain 4 liberties is alive.
@item @option{-K}, @option{--ko-depth @var{depth}}
Deep reading cutoff. Beyond this depth (default 8) GNU Go no longer
tries very hard to analyze kos.
@item @option{--branch-depth @var{depth}}
This sets the @code{branch_depth}, typically a little below the
@code{depth}. Between @code{branch_depth} and @code{depth},
attacks on strings with 3 liberties are considered but branching
is inhibited, so fewer variations are considered. Below this
depth (default 13), GNU Go still tries to attack strings with only
3 liberties, but only tries one move at each node.
@item @option{--break-chain-depth @var{depth}}
Set the @code{break_chain_depth}. Beyond this depth, GNU Go abandons
some attempts to defend groups by trying to capture part of the surrounding
@item @option{--aa-depth @var{depth}}
The reading function @code{atari_atari} looks for combinations beginning
with a series of ataris, and culminating with some string having an
unexpected change in status (e.g. alive to dead or critical). This
command line optio sets the parameter @code{aa_depth} which determines
how deeply this function looks for combinations.
@item @option{--superstring-depth}
A superstring (@pxref{Superstrings}) is an amalgamation of
tightly strings. Sometimes the best way to attack or defend a
string is by attacking or defending an element of the superstring.
Such tactics are tried below @code{superstring_depth} and this
command line option allows this parameter to be set.
The preceeding options are documented with the reading code
(@pxref{Reading Basics}).
@item @option{--owl-branch} Below this depth Owl only considers
@item @option{--owl-reading} Below this depth Owl assumes the
dragon has escaped. Default 20.
@item @option{--owl-node-limit}
If the number of variations exceeds this limit, Owl assumes the dragon can
make life. Default 1000. We caution the user that increasing
@code{owl_node_limit} does not necessarily increase the strength of the
@item @option{--owl-node-limit @var{n}}
If the number of variations exceeds this limit, Owl assumes the dragon can
make life. Default 1000. We caution the user that increasing
@code{owl_node_limit} does not necessarily increase the strength of the
@item @option{--owl-distrust @var{n}}
Below this limit some owl reading is truncated.
@subsection Ascii mode options
@item @option{--color @var{color}}
Choose your color ('black' or 'white').
@item @option{--handicap @var{number}}
Choose the number of handicap stones (0--9)
For more information about the following clock options see @xref{Ascii}.
@item @option{--clock @var{seconds}}
@item @option{--byo-time @var{seconds}}
Number of seconds per (Canadian) byo-yomi period
@item @option{--byo-period @var{stones}}
Number of stones per (Canadian) byo-yomi period
@subsection Development options
@item @option{--replay @var{color}}
Replay all moves in a game for either or both colors. If used with the
@option{-o} option the game record is annotated with move values. This
option requires @option{-l @var{filename}}. The color can be:
@item white: replay white moves only
@item black: replay black moves only
@item both: replay all moves
When the move found by genmove differs from the move in the sgf
file the values of both moves are reported thus:
Move 13 (white): GNU Go plays C6 (20.60) - Game move F4 (20.60)
This option is useful if one wants to confirm that a change such as a
speedup or other optimization has not affected the behavior of the
engine. Note that when several moves have the same top value (or
nearly equal) the move generated is not deterministic (though it can be
made deterministic by starting with the same random seed). Thus a few
deviations from the move in the sgf file are to be expected. Only if the
two reported values differ should we conclude that the engine plays
differently from the engine which generated the sgf file.
@item @option{-a}, @option{--allpats}
Test all patterns, even those smaller in value than the largest move
found so far. This should never affect GNU Go's final move, and it
will make it run slower. However this can be very useful when "tuning"
GNU Go. It causes both the traces and the output file (@option{-o}) to
@item @option{-T}, @option{--printboard}: colored display of dragons.
Use rxvt, xterm or Linux Console. (@pxref{Colored Display})
@item @option{--showtime}
Print timing information to stderr.
@item @option{-E}, @option{--printeyes}: colored display of eye spaces
Use rxvt, xterm or Linux Console. (@pxref{Colored Display})
@item @option{-d}, @option{--debug @var{level}}
Produce debugging output. The debug level is given in hexadecimal, using the
bits defined in the following table from @file{engine/gnugo.h}. A list of
these may be produced using @option{--debug-flags}. Here they are in
@cindex debugging options
DEBUG_MOVE_REASONS 0x0800
DEBUG_OWL_PERFORMANCE 0x1000
DEBUG_READING_PERFORMANCE 0x8000
DEBUG_ATARI_ATARI 0x040000
DEBUG_READING_CACHE 0x080000
DEBUG_OWL_PERSISTENT_CACHE 0X200000
DEBUG_MISCELLANEOUS 0x800000
DEBUG_ORACLE_STREAM 0x1000000
These debug flags are additive. If you want to turn on both
dragon and worm debugging you can use @option{-d0x420}.
@item @option{--debug-flags}
Print the list of debug flags
@item @option{-w}, @option{--worms}
Print more information about worm data.
@item @option{-m}, @option{--moyo @var{level}}
moyo debugging, show moyo board. The @var{level} is fully
documented elsewhere (@pxref{Influential Display}).
@item @option{-b}, @option{--benchmark @var{number}}
benchmarking mode - can be used with @option{-l}. Causes GNU Go to play itself
repeatedly, seeding the start of the game with a few random moves. This method
of testing the program is largely superceded by use of the @command{twogtp}
@item @option{-S}, @option{--statistics}
Print statistics (for debugging purposes).
@item @option{-t}, @option{--trace}
Print debugging information. Use twice for more detail.
@item @option{-r}, @option{--seed @var{seed}}
Set random number seed. This can be used to guarantee that GNU Go will make
the same decisions on multiple runs through the same game. If @code{seed} is
zero, GNU Go will play a different game each time.
@item @option{--decide-string @var{location}}
Invoke the tactical reading code (@pxref{Tactical Reading} to decide
whether the string at @var{location} can be captured, and if so, whether it
can be defended. If used with @option{-o}, this will produce a variation tree
@item @option{--decide-owl @var{location}}
Invoke the owl code (@pxref{The Owl Code}) to decide whether the dragon at
@var{location} can be captured, and whether it can be defended. If used with
@option{-o}, this will produce a variation tree in SGF.
@item @option{--decide-connection @var{location1}/@var{location2}}
Decide whether dragons at @var{location1} and @var{location2} can be connected.
Useful in connection with @option{-o} to write the variations to an SGF file.
@item @option{--decide-dragon-data @var{location}}
Print complete information about the status of the dragon at @var{location}.
@item @option{--decide-semeai @var{location1}/@var{location2}}
At @var{location1} and @var{location2} are adjacent dragons of the
opposite color. Neither is aliveby itself, and their fate (alive,
dead or seki) depends on the outcome of a semeai (capturing race).
Decide what happens. Useful in connection with @option{-o} to
write the variations to an SGF file.
@item @option{--decide-tactical-semeai @var{location1}/@var{location2}}
Similar to @option{--decide-semeai}, except that moves proposed by the
owl code are not considered.
@item @option{--decide-position}
Try to attack and defend every dragon with dragon.escape<6. If
used with @option{-o}, writes the variations to an sgf file.
@item @option{--decide-eye @var{location}}
Evaluates the eyespace at @var{location} and prints a report. You can get
more information by adding @option{-d0x02} to the command line.
(@pxref{Eye Local Game Values}.)
@item @option{--decide-surrounded @var{location}}
A dragon is @emph{surrounded} if it is contained in the convex hull of
its unfriendly neighbor dragons. This does not mean that it cannot escape,
but it is often a good indicator that the dragon is under attack. This
option draws the convex hull of the neighbor dragons and decides whether
the dragon at @var{location} is surrounded.
@item @option{--decide-combination}
Calls the function @code{atari_atari} to decide whether there
exist combinations on the board.
@item @option{--score @var{method}}
Requires @option{-l} to specify which game to score and @option{-L} if
you want to score anywhere else than at the end of the game record.
@var{method} can be "estimate", "finish", or "aftermath". "finish" and
"aftermath" are appropriate when the game is complete, or nearly so, and
both try to supply an accurate final score. Notice that if the game is
not already finished it will be played out, which may take quite a long
time if the game is far from complete. The "estimate" method may be used
to get a quick estimate during the middle of the game. Any of these
options may be combined with @option{--chinese-rules} if you want to use
If the option @option{-o @var{outputfilename}} is provided, the result
will also be written as a comment in the output file. For the "finish"
and "aftermath" scoring algorithms, the selfplayed moves completing the
Finish the game by selfplaying until two passes, then determine the
status of all stones and compute territory.
Finish the game by selfplaying until two passes, then accurately
determine status of all stones by playing out the "aftermath", i.e.
playing on until all stones except ones involved in seki have become
either unconditionally (in the strongest sense) alive or unconditionally
dead (or captured). Slower than @option{--score finish}, and while these
algorithms usually agree, if they differ, @option{--score aftermath} is
most likely to be correct.
@item @code{--score aftermath --capture-all-dead --chinese-rules}
This combination mandates @strong{Tromp-Taylor} scoring. The
Tromp-Taylor ruleset requires the game to be played out until
all dead stones are removed, then uses area (Chinese) scoring.
The option @option{--capture-all-dead} requires the aftermath
code to finish capturing all dead stones.
@subsection Experimental options
Most of these are available as configure options and are
described in @ref{Other Options}.
Print which experimental configure options were compiled into the program.
@item @option{--with-break-in}
@item @option{--without-break-in}
Use or do not use the experimental break-in code. This option
has no effect at level 9 or below. The break in code is enabled
by default at level 10, and the only difference between levels
9 and level 10 is that the break in code is disabled at level 9.
@item @option{--cosmic-gnugo}
Use center oriented influence.
@item @option{--nofusekidb}
Turn off the fuseki database.
@item @option{--nofuseki}
Turn off fuseki moves entirely
@item @option{--nojosekidb}
Turn off the joseki database.
@item @option{--mirror-limit @var{n}}
Stop mirroring when @var{n} stones are on the board.