趣味

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Quickstart

Dependancies

• Python
• IF WINDOWS:
  • mingw
  • lld: error: unable to find library -lvcruntime140, find out how to fix this...

How to run gui

• python scripts\run_gui.py

How to run tests

• python scripts\run_tests.py

intro

This project is a hobby C++ engine written by OhMesch and I. It functions as a fast library exposing useful chess functions such as generate_legal_moves. A python module engine_communicator is also avaliable. There is a serviceable python gui to see the engine in action at driver/show_board.py.

This project has no AI to make intelligent chess moves. There is another repo written by OhMesch and I that consumes this library to write both a Minimax based AI and a Montecarlo AI based on Deepmind's AlphaZero:

• https://github.com/aduerig/chess-ai

todo

• i disabled enpassant and castling temporarily until zobrist hashing works
• zobrist hashing not implemented for enpassant RIGHTS (it works for capture) or castling. it might not be set correctly for turn stuff either.
• I think that the pawn masks for check when the king is on the left and right columns is busted (you can move into check)

building

This project uses CMAKE for C++ parts of the engine. It also exposes a python module written in C++ that can access the board state, and simple engine commands for the purposes of a GUI.

• use the files in the scripts/ folder
• Run before compilation to compile with clang

export CXX=/usr/bin/clang++
export CC=/usr/bin/clang

benchmarking

• note only works if you have callgrind / perf installed
• python scripts/callgrind_minimax.py
• python scripts/perf_minimax.py

developing

• if you are facing "unresolved imports" on vscode in the show_board.py python file, you can create the file .env and add as the contents ** PYTHONPATH=driver

technical notes

probably a good resource

• his blog on magic bitboards

using this as CMAKE + gtest template

https://github.com/bast/gtest-demo

using cpython to compile C extensions to communicate to c++ engine for gui

https://docs.python.org/3/extending/

bit twiddling hacks

http://graphics.stanford.edu/%7Eseander/bithacks.html

for gtest, maybe want to use this

https://gist.github.com/elliotchance/8215283

profiling

• perf (by function)
  • perf record -o ./bin/perf.data -g ./bin/run_minimax_depth $1
  • perf report -g -i ./bin/perf.data
• valgrind (line by line hopefully)
  • valgrind --tool=callgrind ./bin/run_minimax_depth 5
  • kcachegrind callgrind.out.pid
• gprof (line by line)
  • add -pg to complilation, and -l
  • gprof -l ./my_program > analysis.txt

laser

example websocket requests

SEND (periodically, looks like every 9s): {
  "messageType":"ping"
}

SEND: {
  "messageType":"games"
}

GET (x2): {
  "status":"games","data":{"games":[],"nConnections":4}
}

GET: {
  "status": "games",
  "data": {
    "games": [
      {
        "fen": "7q/4pnk1/4prn1/5pp1/1PP5/1NRP4/1KNP4/Q7 b - - 0 1",
        "turn": "b",
        "times": [180000, 180000],
        "increments": [0, 0],
        "lastMoveTime": null,
        "name": [null, "idk"],
        "allFens": { "7q/4pnk1/4prn1/5pp1/1PP5/1NRP4/1KNP4/Q7": 1 },
        "id": "Y6FiSixi56az-oi57EZGH"
      }
    ],
    "nConnections": 4
  }
}

SEND: {
  "messageType":"join","data":{"id":"Y6FiSixi56az-oi57EZGH","name":"lmfao"}
}

GET: {
  "status": "joined",
  "data": {
    "fen": "7q/4pnk1/4prn1/5pp1/1PP5/1NRP4/1KNP4/Q7 b - - 0 1",
    "key": "C28LgQd9apnQ0sP7JGToP",
    "id": "Y6FiSixi56az-oi57EZGH",
    "names": ["lmfao", "idk"],
    "times": [180000, 180000],
    "index": 0,
    "color": "w"
  }
}

GET: {
  "status":"moved","data":{"times":[180000,156899],"move":["f5","e4"],"winner":null}
}

SEND: {
  "messageType":"move","data":{"key":"C28LgQd9apnQ0sP7JGToP","id":"Y6FiSixi56az-oi57EZGH","name":"lmfao","fen":"7q/4pnk1/4prn1/3P2p1/1P2p3/1NRP4/1KNP4/Q7 b - - 0 1","move":["c4","d5"]}
}

GET: {
  "status":"moved","data":{"times":[179901,156899],"move":["c4","d5"],"winner":null}
}

GET: {
  "status":"gameOver","data":{"winner":"w","times":[179901,0]}
}

TO CREATE GAME:

SEND: {"messageType":"create","data":{"fen":"7q/4pnk1/4prn1/5pp1/1PP5/1NRP4/1KNP4/Q7 b - - 0 1","turn":"b","times":[180000,180000],"increments":[0,0],"color":"b","name":"lmfao"}}

GET: {"status":"created","data":{"key":"8p2Lt1nEgcwclSeWQ2XQQ","id":"j2CENKH6XNcmUDtu72VTS"}}
GET: {"status":"games","data":{"games":[{"fen":"7q/4pnk1/4prn1/5pp1/1PP5/1NRP4/1KNP4/Q7 b - - 0 1","turn":"b","times":[180000,180000],"increments":[0,0],"lastMoveTime":null,"name":[null,"lmfao"],"allFens":{"7q/4pnk1/4prn1/5pp1/1PP5/1NRP4/1KNP4/Q7":1},"id":"j2CENKH6XNcmUDtu72VTS"}],"nConnections":3}}

someone joins

GET: {"status":"joined","data":{"fen":"7q/4pnk1/4prn1/5pp1/1PP5/1NRP4/1KNP4/Q7 b - - 0 1","key":"8p2Lt1nEgcwclSeWQ2XQQ","id":"j2CENKH6XNcmUDtu72VTS","names":["idk","lmfao"],"times":[180000,180000],"index":1,"color":"b"}}
GET: {"status":"games","data":{"games":[],"nConnections":3}}