Overview

A bitboard based move generator for Chess. Currently at 50 million nps.

Compile by running make in command line.

Usage:

ChessnutChess only supports these UCI commands at this time:

Angle brackets (<>) indicates an argument to be placed there by the user.

Displaying the current board:

d

Loading a fen:

position fen <fen>

Running a perft from the current position:

go perft <depth>

Quitting:

quit

GUI

The GUI is coded in Python with Cython bindings to the C++ move gen.

Prerequisites

NumPy, Pygame, and Cython are needed to run the GUI. Install the packages through command line using:

python3 -m pip install numpy pygame Cython

Compliation

To compile run make cython in command line. If that doesn't work, run python3 GUI/setup.py build_ext instead.

You may need to change the compiler flags in setup.py depending on which compiler Cython decides to use.
If Cython is using g++ or clang, change the contents of setup.py to:

from setuptools import setup, Extension
from Cython.Build import cythonize

setup(ext_modules=cythonize(
    Extension(
        "chess",
        ["./GUI/chess.pyx",
        "./src/masks.cpp",
        "./src/bits.cpp",
        "./src/piece.cpp",
        "./src/game.cpp"
        ],
        language="c++",
        extra_compile_args=["-O3", "std=c++17"],
    )
), options={'build_ext':{'build_lib':'./GUI'}})

Run

Run main.py to play Chess!

Details

Moves are generated using pre-computed masks generated by a Python script, masks.py.

Sliding piece moves are generated using magic bitboards.

Takes inspiration from nkarve's surge