World Conquest Chronicles

World Conquest Chronicles

go-chess-models, v1.9.0

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The library that implements checking and generating of chess moves.

Adding the boards.BitBoard structure; adding the go-chess-moves and go-chess-comparator tools.

Change Log

  • new features:
    • the boards.BitBoard structure:
      • add the boards.BitBoard structure;
      • add the boards.BitBoard structure to the go-chess-perft tool;
    • add the go.mod file;
    • tools:
      • improve the go-chess-perft tool:
        • improve the documentation;
        • improve the options;
        • validate the deep option;
      • add the go-chess-moves tool;
      • add the go-chess-comparator tool;
  • refactoring:
    • fix the code style with the golangci-lint tool;
  • unit testing:
    • improve the tests of the ApplyMove() methods;
  • examples:
    • move the tests of the boards package to the right place.

Features

  • representing the board:
    • as an associative array of pieces with their positions as keys;
    • as a plain array of pieces with exact correspondence array indices to piece positions;
    • as a set of integers corresponding to a particular combination of piece color and type, and where each bit corresponds to a particular piece position (so-called a bitboard);
  • immutable applicating moves to the board via copying the latter;
  • checkings of moves:
    • universal;
    • individual for all types of pieces;
  • generating moves via filtering from all possible ones;
  • move restrictions (abandoned moves):
    • pawn double-move;
    • en passant capture;
    • promotion;
    • castling;
  • perft function;
  • using an abstraction of a piece;
  • Forsyth-Edwards Notation:
    • parsing:
      • of a position;
      • of a move;
      • of a piece kind;
      • of a piece color;
      • of a board;
    • serialization:
      • of a position;
      • of a move;
      • of a piece kind;
      • of a piece color;
      • of a board;
  • utilities:
    • utility for counting all possible moves (based on the perft function);
    • utility for generating all possible chess moves;
    • utility for comparing the generation of all possible chess moves by different board representations.

Benchmarks

The chessmodels.Perft() function used the boards.BitBoard structure:

BenchmarkPerft/BitBoard/initial/1Ply-8               284       4036298 ns/op       958048 B/op     35888 allocs/op
BenchmarkPerft/BitBoard/initial/2Ply-8                20      54032966 ns/op     11627104 B/op    433592 allocs/op
BenchmarkPerft/BitBoard/initial/3Ply-8                 2     708741154 ns/op    169201536 B/op   6300499 allocs/op
BenchmarkPerft/BitBoard/kiwipete/1Ply-8               74      14372268 ns/op      3546305 B/op    124803 allocs/op
BenchmarkPerft/BitBoard/kiwipete/2Ply-8                2     637371490 ns/op    138270896 B/op   4866744 allocs/op

Installation of the go-chess-moves Tool

$ go install github.com/thewizardplusplus/go-chess-models/cmd/go-chess-moves@latest

Usage of the go-chess-moves Tool

$ go-chess-moves -h | -help | --help
$ go-chess-moves [options]

Options:

  • -h, -help, --help — show the help message and exit;
  • -storage {map|slice|bits} — piece storage kind (default: slice);
  • -fen STRING — board in Forsyth-Edwards Notation (default: rnbqk/ppppp/5/PPPPP/RNBQK, i.e., Gardner's minichess);
  • -color {black|white} — color that moves first (default: white).

Installation of the go-chess-comparator Tool

$ go install github.com/thewizardplusplus/go-chess-models/cmd/go-chess-comparator@latest

Usage of the go-chess-comparator Tool

$ go-chess-comparator -h | -help | --help
$ go-chess-comparator [options]

Options:

  • -h, -help, --help — show the help message and exit;
  • -fen STRING — board in Forsyth-Edwards Notation (default: rnbqk/ppppp/5/PPPPP/RNBQK, i.e., Gardner's minichess);
  • -color {black|white} — color that moves first (default: white);
  • -mode {depth-first|breadth-first} — comparing mode (default: depth-first);
  • -deep INTEGER — analysis deep (should be greater than or equal to zero; default: 5).

Repository

Link: https://github.com/thewizardplusplus/go-chess-models/tree/v1.9.0.

Content: code.

License: MIT.

Screenshots

Running of the go-chess-moves tool

Running of the go-chess-comparator tool (depth-first comparing mode)

Running of the go-chess-comparator tool (breadth-first comparing mode)