#undef S
+ // Bonus for having the side to move (modified by Joona Kiiski)
+ const Score Tempo = make_score(24, 11);
+
// Rooks and queens on the 7th rank (modified by Joona Kiiski)
const Score RookOn7thBonus = make_score(47, 98);
const Score QueenOn7thBonus = make_score(27, 54);
// happen in Chess960 games.
const Score TrappedBishopA1H1Penalty = make_score(100, 100);
- // Penalty for BNR that is not defended by anything
- const Score UndefendedPiecePenalty = make_score(25, 10);
+ // Penalty for an undefended bishop or knight
+ const Score UndefendedMinorPenalty = make_score(25, 10);
// The SpaceMask[Color] contains the area of the board which is considered
// by the space evaluation. In the middle game, each side is given a bonus
Value margins[2];
Score score, mobilityWhite, mobilityBlack;
- // Initialize score by reading the incrementally updated scores included
- // in the position object (material + piece square tables).
- score = pos.psq_score();
-
// margins[] store the uncertainty estimation of position's evaluation
// that typically is used by the search for pruning decisions.
margins[WHITE] = margins[BLACK] = VALUE_ZERO;
+ // Initialize score by reading the incrementally updated scores included
+ // in the position object (material + piece square tables) and adding
+ // Tempo bonus. Score is computed from the point of view of white.
+ score = pos.psq_score() + (pos.side_to_move() == WHITE ? Tempo : -Tempo);
+
// Probe the material hash table
- ei.mi = Threads[pos.this_thread()].materialTable.probe(pos);
+ ei.mi = pos.this_thread()->materialTable.probe(pos);
score += ei.mi->material_value();
// If we have a specialized evaluation function for the current material
}
// Probe the pawn hash table
- ei.pi = Threads[pos.this_thread()].pawnTable.probe(pos);
+ ei.pi = pos.this_thread()->pawnTable.probe(pos);
score += ei.pi->pawns_value();
// Initialize attack and king safety bitboards
const Color Them = (Us == WHITE ? BLACK : WHITE);
- Bitboard b, undefended, undefendedMinors, weakEnemies;
+ Bitboard b, undefendedMinors, weakEnemies;
Score score = SCORE_ZERO;
- // Undefended pieces get penalized even if not under attack
- undefended = pos.pieces(Them) & ~ei.attackedBy[Them][0];
- undefendedMinors = undefended & (pos.pieces(BISHOP) | pos.pieces(KNIGHT));
+ // Undefended minors get penalized even if not under attack
+ undefendedMinors = pos.pieces(Them)
+ & (pos.pieces(BISHOP) | pos.pieces(KNIGHT))
+ & ~ei.attackedBy[Them][0];
if (undefendedMinors)
- score += single_bit(undefendedMinors) ? UndefendedPiecePenalty
- : UndefendedPiecePenalty * 2;
- if (undefended & pos.pieces(ROOK))
- score += UndefendedPiecePenalty;
+ score += single_bit(undefendedMinors) ? UndefendedMinorPenalty
+ : UndefendedMinorPenalty * 2;
// Enemy pieces not defended by a pawn and under our attack
weakEnemies = pos.pieces(Them)