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                                                                 a uci chess engine

I got frustrated about how bad I was at playing chess, so I decided to write myself a chess engine and let the computer do it for me! Not intending to use it against unaware non engine players. This whole project initially started with my old engine Gambit.

Has become more of a obsession lately, and a play ground to try out some C++ I wouldn't write at work.

First commit of Gambit was done on September the 13th, 2017. Since then I retired that engine and all my effort is going into elephant.

Taking a test driven approach and implemented compatibilty with OpenBench, of which I have a instance running locally.

Reading a lot on https://talkchess.com and the endless resource https://chessprogramming.org amongst other resources on the internet. Community on Engine Programmer discord & OpenBench Discord have been very great and helpful.

Been very inspired by Ciekce's Polaris zzzzz151's Starzix Analog Hors' blog Sebastian Lague's Coding Adventures

Performance

all performance numbers are from running on my local machine, AMD Ryzen 9 5950x

Features

• Engine:

  • bitboards

• Search:

  • alpha beta neg max
  • quiescence search
  • transposition table
  • pv priority
  • killer heuristic
  • late move reduction

• Evaluation:

  • material
  • position tables
  • tapered position evaluation
  • king safety
  • passed pawn
  • mop-up

• API:

  • "user friendly" cli interface
  • UCI compatible
  • OpenBench compatible - https://github.com/AndyGrant/OpenBench

Goals & todo

• null move pruning

• multi threaded search

• reach elo 2000

• github.io page?

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Prerequisites

This is a C++20 project and I'm not distributing any binaries, so to run the engine you need to compile it yourself.

Currently requiering a compiler which compiles C++20.

Installing and Building

Through your choice of means, clone the repository.

git bash example:

git clone --recursive https://github.com/looak/elephant.git

Windows

Easiest way to get running on Windows is installing Visual Studio Code and extensions for cmake projects, or Visual Studio Community and opening the initial CMakeLists.txt.

Linux

• Create a build directory:

$ mkdir build
$ cd build

• Call Cmake:

$ cmake ..

• Build:

$ make

Running Elephant Gambit

Interfacing with elephant can nativly be done through ElephantCLI. As of v0.4.0 supports UCI protocol and you can interface it with your Chess GUI of choice. Personally, I have been using Arena & CuteChess. Every so often I'll host the engine locally and one can play against it on lichess.org.

Running the tests

Either run the output binary ElephantTest after build or browse to .\build\ and execute ctest.

Versioning

We use SemVer for versioning. For the versions available, see the tags on this repository.

Authors

• Alexander Loodin Ek - Initial work - looak

[future-link] https://github.com/looak/elephant/tree/future