Tuesday, June 25, 2013

It's getting hotter

After the recent release of my engine it now starts playing in tournaments replacing its previous version. Those games are usually played at much longer time controls that I had used in the development. If a chess engine has something like a personalty or style it will show itself in such games.

It looks it has a rather speculative style. It doesn't fear to give away material to improve its position. And as the positional factors in its evaluation can reach rather big values it might sacrifice a lot. Probably this is not always sound but it creates interesting games.

Here is a position after move 15 from a game it played against Delphil 2.9g 64 bit (2529 ELO in CCRL). Time Control was 40 moves in 25 minutes and its a game from the latest Division 5 tournament of Graham Banks.

iCE 1.0 vs Delphil 2.9g, position after 15. .. Bd4

  iCE is already a pawn down
  iCE has its rook at the open d-file opposing blacks queen

  Black has an weak isolated double pawn at the c5 file
  Blacks knight lacks some mobility
  Blacks king safety is a bit damaged

So if down in material give away some more. 16. Rxd4 (giving the rook for a bishop and a pawn)

16. Rxd4 cxd4  17. Qxd4+ Kg8  18. Qc4 e6  19. e5 g5  20. Ne4 Rf5  21. Bd2 Rxe5

iCE 1.0 vs Delphil 2.9g, position after 21. .. Rxe5

  iCE is now down a rook and a pawn vs. a bishop


  it has the bishop pair

  the white knight has good destinations
  the white king is safe

  the black bishop at d7 is not more than a big pawn
  the c6 and e6 pawns are weak
  the black knight is still at the rim
  the king is exposed

22. Bc3 Rf5  23. Rd1 g4  24. Nc5 Rd5  25. Rxd5 exd5  26. Qd4 Qe7  27. Nxd7 Qxd7

iCE 1.0 vs Delphi 2.9g, 27. .. Qxd7 and Black resigns

iCE was still down in material when Black resigned

Black resigned because iCE has now a combination that wins all of blacks material leaving him only 4 pawns while keeping its bishop pair and pawns.

It starts with 28. Qh8+ Kf7 29. Qxh7+ Ke8 30. Qxh6

Unfortunately its non materialistic style does not always work but at least there is some action on the board.