Omar Computer Chess Player



What is this?: A computer chess player.

What is Omar and Guimar?: A program able to play chess conforming to a chess protocol is called a chess engine. Chess engines are pluggable into most of commercial chess programs. However it is not nice playing just with a console chess player, so there are attractive Windows chess programs. Omar is a chess engine, Guimar is the related chess Windows program.

What is new for the chess-computing community?: Nothing. There are many other chess engines. This is not particularly strong, nor use new techniques for the moment. However, it is quite simple, and well documented source code is available.

Is it finished?: It is still under development. A stable version is coming soon, but this latest version offers a playable interface.

Which OS / compilers are supported? At first, the core Omar was compiled into Windows and Unix. Later on, Unix support was discontinued. However, it can still compile with different compilers: this last version has been tested with Visual C++ 6.0, Visual Studio.NET and Dev-cpp with g++.

Was made it on a powerful computer? Nope!. It was started with a P133 with 16Mb..

What does Omar mean?: It is a tribute to Omar Khayyam.

What is the language?: Guimar is in Spanish. Documentation, in English..

Who´s the developer?: A not very talented chessplayer.



Omar 3.1 binaries for Windows.

Documentation online


If you just want to play chess, use the GUIMAR interface, by running "guimar.exe".

If you want to plug the engine into a chess program, then probably you know how to. Winboard is recommended. It has also been tested on Arena.

Debug information has been disabled in this compiled version.

Technical issues

  • Depth first search: YES.
  • Alpha-Beta pruning: YES
  • Principal variant search: YES
  • Quiescience search: YES
  • Iterative deepening: YES (disabled in this version)
  • Aspiration window: (coming soon)
  • Killer move heuristic: YES
  • Book opening: SMALL
  • Null move heuristic: NO
  • Variable depth search: NO
  • Transposition tables: YES
  • Learning capabilities: NO
  • Oponent time thinking: NO
  • Board representation: char array, 120-bytes. Not bitboard oriented.
  • Programming language: C++
  • Graphical interface: winboard/xboard compatible and text.
  • Platforms: Initially, all of them. In newer versions, only Windows.

Leo Dijksman is the reference webpage for serious chess engines.
This software was developed with the help of some of the fantastic free software collection.