Tweak kingAttackersCount and KingAttackWeights
Use the whole kingRing for pawn attackers instead of only the squares directly around the king. This tends to give quite a lot more kingAttackersCount, so to compensate and to avoid raising the king danger too fast we lower the values in the KingAttackWeights array a little bit. STC: LLR: 2.95 (-2.94,2.94) [0.00,4.00] Total: 51892 W: 10723 L: 10369 D: 30800 http://tests.stockfishchess.org/tests/view/5af6d4dd0ebc5968e652428e LTC: LLR: 2.96 (-2.94,2.94) [0.00,4.00] Total: 24536 W: 3737 L: 3515 D: 17284 http://tests.stockfishchess.org/tests/view/5af709890ebc5968e65242ac Credits to user @xoroshiro for the idea of using the kingRing for pawn attackers. How to continue? It seems that the KingAttackWeights[] array stores values which are quite Elo-sensitive, yet they have not been tuned with SPSA recently. There might be easy Elo points to get there. Closes https://github.com/official-stockfish/Stockfish/pull/1597 Bench: 5282815pull/1599/head
parent
c163c2fcb0
commit
bf01bd0755
1
AUTHORS
1
AUTHORS
|
@ -118,3 +118,4 @@ Tom Vijlbrief (tomtor)
|
|||
Torsten Franz (torfranz)
|
||||
Uri Blass (uriblass)
|
||||
Vince Negri
|
||||
xoroshiro
|
||||
|
|
|
@ -89,7 +89,7 @@ namespace {
|
|||
constexpr Value SpaceThreshold = Value(12222);
|
||||
|
||||
// KingAttackWeights[PieceType] contains king attack weights by piece type
|
||||
constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 };
|
||||
constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 77, 55, 44, 10 };
|
||||
|
||||
// Penalties for enemy's safe checks
|
||||
constexpr int QueenSafeCheck = 780;
|
||||
|
@ -281,7 +281,7 @@ namespace {
|
|||
else if (file_of(pos.square<KING>(Us)) == FILE_A)
|
||||
kingRing[Us] |= shift<EAST>(kingRing[Us]);
|
||||
|
||||
kingAttackersCount[Them] = popcount(attackedBy[Us][KING] & pe->pawn_attacks(Them));
|
||||
kingAttackersCount[Them] = popcount(kingRing[Us] & pe->pawn_attacks(Them));
|
||||
kingAttacksCount[Them] = kingAttackersWeight[Them] = 0;
|
||||
}
|
||||
else
|
||||
|
|
Loading…
Reference in New Issue