The Chess Variant Pages



Pixelpusher

Nowadays, you can buy many very strong computer programs for your PC. The newest version of Rebel is challenging grandmaster and nearly world-champion Anand. Programs have ELO-ratings, much higher than most of us can even dream to get close to. The Pixelpusher program takes a step in the other direction: it is might well the weakest playing chess program in the world! Pixelpusher namely just makes a random legal move. If you are again beaten up badly by your commercial chess playing program, try Pixelpusher!

Well, this is just my version 0.02 of a chess playing applet. Related applets play chess variants, and they play it just as bad. To tell the truth, I actually hope to make the program a little stronger, but have to work on that yet.

This only works with Java enabled browsers.

Above, you see an applet in working. It plays a game of chess against you.

  1. To make a move, first (left) click on a piece, and then on its destination square.
  2. To deselect a piece, (left) click again on the selected piece.
  3. To castle, (left) click on the king and then on its destination square. The rook moves automatically with it.
  4. To go back to the original setup, click with the right mouse button on the board. If you have a one-button mouse, click and press the alt or control button at the same time.
  5. The applet checks legality of the moves, including check. It follows the chess moves precisely, except that it does not allow you to promote a piece to something different from a queen, and:
  6. The applet does not determine stalemate or mate, draw by repetition, or draw by the 50 moves rule.

Known bugs

  1. Promotion is automatically to a queen. Minor-promotion is not possible.
  2. The applet does not detect the end of a game.
  3. The computer just makes the first legal move he sees. It is actually more difficult to lose from the computer than to win from it.
  4. The computer only plays black.

Version

This is version 0.02 of the chess playing applet. There may not have been a chess program made public that plays as bad as this one, except possibly version 0.01 that played the first legal move it sees. Actually, some programs are worse: programs that always hang, programs that make illegal moves, etc. Such commercial programs are also available, but perhaps even less fun than this applet.

A challenge

Can you lose from this program?

The name

I named it Pixelpusher, after the name `woodpusher' for a chess player that actually do not think when they play a game of chess.

Plans

Improve the play of the program: use position evaluation, alpha-beta search, hash tables, endgame subroutines... It is not however my intention to make this a very strong program. Rewrite it from scratsch, to get code that is less of the mess this code is. Make similar applets for chess variants.

Comments?

Comments are appreciated. Send email to Hans Bodlaender. Email me also if you want the source code, or want to help me improving the code.
WWW page and applet by Hans Bodlaender.
WWW page created: April 3, 1998.