auri

“She knew the true shape of the world. All else was shadow and the sound of distant drums.”

tei interface

/tei exposes a minimalistic tei interface, that can be compiled with make tei (resulting in the bin /bin/tei). Supported commands are:

script-like usage

tei now replace the old scripts, as it can be used like

echo "random -n 10" | tei
tei <<< "move a1 b2" <<< "print tps"
xdg-open $(tei <<< "tps 1,1,12,x2/x5/x5/x5/2,x4 1 4" <<< "ninja")

[!NOTE] here-strings (<<<) des not chain in default bash, a shell like zsh is required insthead.

Everything that is not data is regarded as log and printed to a different stream (by default stderr), so that it can be discarded with 2>/dev/null.

taklib

taklib, located in /lib, is meant as a fast (TODO: bench) header-only c library for handling a tak game, used as a base for the other tools implemented in auri. Implemented features are:

• [x] bitboard position representation
• [x] moves (placements and spreads) generation and application
• [x] zobrist hashing + transposition table
• [x] tei interface + some commands

For more informations regarding the positon encoding and the moves generation strategy see the docs.

examples

importing taklib

taklib is a set of header-only c files. If you are confused by this definition, this should help. Altough kinda controversial, this choice makes a lot of things easier, and as a user the only difference is that, before importing, it's necesary to define the TAKLIB_IMPLEMENTATION macro:

// first we define the macro
#define TAKLIB_IMPLEMENTATION

// then we include the headers we need
#include "tak.h"
#include "ptn.h"

creating an empty position

a position is the representation of a state of the board, like a "screenshot" of a moment in a game where a move has just been made.

// this creates a new, empty, position
tak_position pos = tak_newposition(5);

There are two lookup tables that are required to run most of the functionalities of the library: tak_slt and tak_zobrist_data. The first contains all the possible spread configurations and is used to search for spreads, while the second one contains the randomly generated bitstrings needed fot zobrist hashing.

tak_slt slt = tak_slt_load();
tak_zobrist_data zd = tak_zd_load();

moves

A tak move is handled by taklib as a combination of anonymous unions and structs that allows to have the same struct (tak_move) represent both a placement and a spread, and the field tak_move.type is set to TAK_SPREAD of TAK_PLACEMENT to indicate it's type.

Moves can be created manually, although not so convenient, or can be searched for

// create a buffer to store found moves
tak_move buffer[TAK_MAX_MOVES];

// search all legal moves in a given position
int n = tak_search(buffer, &pos, &slt); // returns the amount of 
                                        // moves found

Spreads and placements can also be searched individually with tak_search_spreads and tak_search_placements.

[!NOTE] By default taklib assumes swap opening. If we desire to remove this, we can set the TAKLIB_SWAP macro to 0 (or a different number to modify the number of plies for which the rule apply, default 2) both in code

#define TAKLIB_SWAP 0
#include "tak.h"  // no swap now

or at compilation time with -DTAKLIB_SWAP=0 (on GCC).

To apply a move simply

tak_position before = tan_newposition(5);
tak_position after = tak_do(before, a_move, &zd);

and the type-specifics functions are tak_do_spread and tak_do_placement. As the tak_do* functions copy the "before" position insthead of modifying it no tak_undo* is required. This proved to be faster with optimized GCC builds than passing references and undoing.

handling tps strings

tps string are handled using the ptn.h module. We can parse a string into a position

char tps_string[] = "x3,12,2S/x,22S,22C,11,21/121,212,12,1121C,1212S/21S,1,21,211S,12S/x,21S,2,x2 1 26";
tak_position pos = tps_parse(tps_string, TPS_STD, &zd);

The &zd parameter is a reference to the zobrist lookup table we made earlier, while TPS_STD is the standard tps lexicon. A lexicon, both in tps and ptn, is a set of declarations that defines the characters used to represent stuff in the strings.

We can also encode a previously created position as a new tps string

// create a new position, loading it from a tps string
tak_position pos = tps_parse("x3/x3/x3 1 1");

// and encode it into a new string
char tps[TPS_MAX_LENGTH];
int n = tps_encode(tps, pos, TPS_STD); // returns the amout of charachters
                                       // written into `tps, included '\0'

assert(strcmp(tps, "x3/x3/x3 1 1") == 0) // true

[!WARNING] Loading both tps and ptn strings does not imply a legality check (yet), so trying to load a faulty string can lead to a variety of side effects, ranging from strangely-formed position to segfaults.

handling ptn moves

ptn-encoded moves can be handled in a similar manner as tpsstrings

// load
tak_move move = ptn_parse("4d2>112*");

// and encode
char ptn[PTN_MAX_MOVE_LENGTH];
int n = ptn_encode(ptn, move, /*the size of the board*/ 5, PTN_STD),

Note that loading a ptn move is unrelated from any position, so before applying a loaded move to a position without assertions may be risky.

There is a utility function that allows to parse a position from a list of ptn moves

char *moves[] = {"a1", "a2", "b1<"};
tak_position p = ptn_apply(tak_newposition(3), moves, 3, PTN_STD, &zd);

// -> p = 21,x/x3/x3 2 2