Re: Huge simplification
Posted: Sat Apr 26, 2014 4:09 am
And the same goes true about implementation of closed positions.
[d]6k1/8/4p3/3pP3/3P4/8/8/6K1 w - - 0 1
With this pawn constellation, give penalty for the short-castled black king. Well, it makes some sense, as the chain is pointed towards the enemy black king, however what if:
1. there is a black pawn on f5. In this case the position on the king side is already sufficiently closed for the black king to bother
2. black has good counterplay on the queen side, in this case the pawn structure is already not that efficient
The conclusion would be that this is not a real closed position that white could frequently enough use to its advantage.
[d]6k1/5p2/4p3/3pP3/2pP4/2P5/8/6K1 w - - 0 1
Adding one more file of blocked pawns along the c file, plus an f7 pawn. Well, this is already a real closed position. The advantages of this implementation over the previous one:
1. the f7 black pawn ensures that black still has not played f5, this pawn is vulnerable, and white could use this situation to organize an efficient king side attack
2. the further pair of blocked pawns on the c file ensures that, even if black has some counterplay on the queen side, it will develop much less rapidly, as a larger portion of the board is blocked. This gives white sufficient time to organize king side attack.
Well, this is really a closed position, a closed position engines should learn to play more satisfactorily.
[d]6k1/6p1/5p2/4pP2/3pP3/3P4/8/6K1 w - - 0 1
And another closed position with the same characteristics, only shifted one file to the right. Those, with the 2 mirror black cases, are the 2 main closed position types. It is enough to code just those 2 types so that an engine has sufficient knowledge of closed positions. The second posted position from black's point of view is actually the KID itself.
[d]6k1/8/3p4/3Pp3/4Pp2/5P2/6P1/6K1 w - - 0 1
But of course, the KID is everywhere, you can enter KID structures from a very wide range of positions. And also, there are many other features and eval terms associated with KID structures, but the above simple rule is the most necessary and basic rule defining closed game with attacking opportunities for one of the sides. (to be distinguished from an entirely blocked position, or a fortress, which only ensures a draw, but gives no real winning chances for one of the sides, as in this case)
[d]6k1/8/4p3/3pP3/3P4/8/8/6K1 w - - 0 1
With this pawn constellation, give penalty for the short-castled black king. Well, it makes some sense, as the chain is pointed towards the enemy black king, however what if:
1. there is a black pawn on f5. In this case the position on the king side is already sufficiently closed for the black king to bother
2. black has good counterplay on the queen side, in this case the pawn structure is already not that efficient
The conclusion would be that this is not a real closed position that white could frequently enough use to its advantage.
[d]6k1/5p2/4p3/3pP3/2pP4/2P5/8/6K1 w - - 0 1
Adding one more file of blocked pawns along the c file, plus an f7 pawn. Well, this is already a real closed position. The advantages of this implementation over the previous one:
1. the f7 black pawn ensures that black still has not played f5, this pawn is vulnerable, and white could use this situation to organize an efficient king side attack
2. the further pair of blocked pawns on the c file ensures that, even if black has some counterplay on the queen side, it will develop much less rapidly, as a larger portion of the board is blocked. This gives white sufficient time to organize king side attack.
Well, this is really a closed position, a closed position engines should learn to play more satisfactorily.
[d]6k1/6p1/5p2/4pP2/3pP3/3P4/8/6K1 w - - 0 1
And another closed position with the same characteristics, only shifted one file to the right. Those, with the 2 mirror black cases, are the 2 main closed position types. It is enough to code just those 2 types so that an engine has sufficient knowledge of closed positions. The second posted position from black's point of view is actually the KID itself.
[d]6k1/8/3p4/3Pp3/4Pp2/5P2/6P1/6K1 w - - 0 1
But of course, the KID is everywhere, you can enter KID structures from a very wide range of positions. And also, there are many other features and eval terms associated with KID structures, but the above simple rule is the most necessary and basic rule defining closed game with attacking opportunities for one of the sides. (to be distinguished from an entirely blocked position, or a fortress, which only ensures a draw, but gives no real winning chances for one of the sides, as in this case)