// Pointer to pawn hash table entry
PawnInfo* pi;
+ // updateKingTables[color] is set to true if we have enough material
+ // to trigger the opponent's king safety calculation. When is false we
+ // skip the time consuming update of the king attackers tables.
+ bool updateKingTables[2];
+
// attackedBy[color][piece type] is a bitboard representing all squares
// attacked by a given color and piece type, attackedBy[color][0] contains
// all squares attacked by the given color.
const int KingAttackWeights[] = { 0, 0, 2, 2, 3, 5 };
// Bonuses for enemy's safe checks
- const int QueenContactCheckBonus = 3;
- const int QueenCheckBonus = 2;
- const int RookCheckBonus = 1;
+ const int QueenContactCheckBonus = 6;
+ const int QueenCheckBonus = 3;
+ const int RookCheckBonus = 2;
const int BishopCheckBonus = 1;
const int KnightCheckBonus = 1;
Phase phase = mi->game_phase();
- // Middle-game specific evaluation terms
- if (phase > PHASE_ENDGAME)
+ // Evaluate space for both sides, only in middle-game.
+ if (phase > PHASE_ENDGAME && mi->space_weight() > 0)
{
- // Evaluate pawn storms in positions with opposite castling
- if ( square_file(pos.king_square(WHITE)) >= FILE_E
- && square_file(pos.king_square(BLACK)) <= FILE_D)
-
- bonus += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0);
-
- else if ( square_file(pos.king_square(WHITE)) <= FILE_D
- && square_file(pos.king_square(BLACK)) >= FILE_E)
-
- bonus += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0);
-
- // Evaluate space for both sides
- if (mi->space_weight() > 0)
- {
- int s = evaluate_space<WHITE, HasPopCnt>(pos, ei) - evaluate_space<BLACK, HasPopCnt>(pos, ei);
- bonus += apply_weight(make_score(s * mi->space_weight(), 0), Weights[Space]);
- }
+ int s = evaluate_space<WHITE, HasPopCnt>(pos, ei) - evaluate_space<BLACK, HasPopCnt>(pos, ei);
+ bonus += apply_weight(make_score(s * mi->space_weight(), 0), Weights[Space]);
}
// If we don't already have an unusual scale factor, check for opposite
Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from<KING>(pos.king_square(Them));
ei.kingZone[Us] = (b | (Us == WHITE ? b >> 8 : b << 8));
ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us);
- b &= ei.attackedBy[Us][PAWN];
- ei.kingAttackersCount[Us] = b ? count_1s_max_15<HasPopCnt>(b) / 2 : EmptyBoardBB;
- ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = EmptyBoardBB;
+ ei.updateKingTables[Us] = pos.piece_count(Us, QUEEN) && pos.non_pawn_material(Us) >= QueenValueMidgame + RookValueMidgame;
+ if (ei.updateKingTables[Us])
+ {
+ b &= ei.attackedBy[Us][PAWN];
+ ei.kingAttackersCount[Us] = b ? count_1s_max_15<HasPopCnt>(b) / 2 : EmptyBoardBB;
+ ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = EmptyBoardBB;
+ }
}
ei.attackedBy[Us][Piece] |= b;
// King attacks
- if (b & ei.kingZone[Us])
+ if (ei.updateKingTables[Us] && (b & ei.kingZone[Us]))
{
ei.kingAttackersCount[Us]++;
ei.kingAttackersWeight[Us] += KingAttackWeights[Piece];
const Square ksq = pos.king_square(Us);
// King shelter
- Score bonus = ei.pi->king_shelter(pos, Us, ksq);
+ Score bonus = ei.pi->king_shelter<Us>(pos, ksq);
// King safety. This is quite complicated, and is almost certainly far
// from optimally tuned.
- if ( ei.kingAttackersCount[Them] >= 2
- && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame
- && pos.piece_count(Them, QUEEN) >= 1
+ if ( ei.updateKingTables[Them]
+ && ei.kingAttackersCount[Them] >= 2
&& ei.kingAdjacentZoneAttacksCount[Them])
{
// Find the attacked squares around the king which has no defenders
attackUnits = Min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
+ 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s_max_15<HasPopCnt>(undefended))
+ InitKingDanger[relative_square(Us, ksq)]
- - mg_value(ei.pi->king_shelter(pos, Us, ksq)) / 32;
+ - mg_value(ei.pi->king_shelter<Us>(pos, ksq)) / 32;
// Analyse enemy's safe queen contact checks. First find undefended
// squares around the king attacked by enemy queen...