struct EvalInfo {
// Pointers to material and pawn hash table entries
- MaterialInfo* mi;
- PawnInfo* pi;
+ MaterialEntry* mi;
+ PawnEntry* pi;
// attackedBy[color][piece type] is a bitboard representing all squares
// attacked by a given color and piece type, attackedBy[color][0] contains
#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 a minor piece that is not defended by anything
+ // 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
Score evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei);
- inline Score apply_weight(Score v, Score weight);
- Value scale_by_game_phase(const Score& v, Phase ph, ScaleFactor sf);
+ Value interpolate(const Score& v, Phase ph, ScaleFactor sf);
Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight);
double to_cp(Value v);
void trace_add(int idx, Score term_w, Score term_b = SCORE_ZERO);
template<bool Trace>
Value do_evaluate(const Position& pos, Value& margin) {
+ assert(!pos.in_check());
+
EvalInfo ei;
Value margins[2];
Score score, mobilityWhite, mobilityBlack;
- assert(pos.thread() >= 0 && pos.thread() < MAX_THREADS);
- assert(!pos.in_check());
-
- // Initialize score by reading the incrementally updated scores included
- // in the position object (material + piece square tables).
- score = pos.value();
-
// 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.thread()].materialTable.material_info(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.thread()].pawnTable.pawn_info(pos);
+ ei.pi = pos.this_thread()->pawnTable.probe(pos);
score += ei.pi->pawns_value();
// Initialize attack and king safety bitboards
// If we don't already have an unusual scale factor, check for opposite
// colored bishop endgames, and use a lower scale for those.
if ( ei.mi->game_phase() < PHASE_MIDGAME
- && pos.opposite_colored_bishops()
+ && pos.opposite_bishops()
&& sf == SCALE_FACTOR_NORMAL)
{
// Only the two bishops ?
sf = ScaleFactor(50);
}
- // Interpolate between the middle game and the endgame score
margin = margins[pos.side_to_move()];
- Value v = scale_by_game_phase(score, ei.mi->game_phase(), sf);
+ Value v = interpolate(score, ei.mi->game_phase(), sf);
// In case of tracing add all single evaluation contributions for both white and black
if (Trace)
{
- trace_add(PST, pos.value());
+ trace_add(PST, pos.psq_score());
trace_add(IMBALANCE, ei.mi->material_value());
trace_add(PAWN, ei.pi->pawns_value());
trace_add(MOBILITY, apply_weight(mobilityWhite, Weights[Mobility]), apply_weight(mobilityBlack, Weights[Mobility]));
Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W);
if (pos.piece_on(s + d) == make_piece(Us, PAWN))
{
- if (!pos.square_is_empty(s + d + pawn_push(Us)))
+ if (!pos.square_empty(s + d + pawn_push(Us)))
score -= 2*TrappedBishopA1H1Penalty;
else if (pos.piece_on(s + 2*d) == make_piece(Us, PAWN))
score -= TrappedBishopA1H1Penalty;
const Color Them = (Us == WHITE ? BLACK : WHITE);
- Bitboard b;
+ Bitboard b, undefendedMinors, weakEnemies;
Score score = SCORE_ZERO;
// Undefended minors get penalized even if not under attack
- const Bitboard undefended = pos.pieces(Them)
- & (pos.pieces(BISHOP) | pos.pieces(KNIGHT))
- & ~ei.attackedBy[Them][0];
- if (undefended) {
- score += UndefendedMinorPenalty;
- if (!single_bit(undefended))
- score += UndefendedMinorPenalty;
- }
+ undefendedMinors = pos.pieces(Them)
+ & (pos.pieces(BISHOP) | pos.pieces(KNIGHT))
+ & ~ei.attackedBy[Them][0];
+
+ if (undefendedMinors)
+ score += single_bit(undefendedMinors) ? UndefendedMinorPenalty
+ : UndefendedMinorPenalty * 2;
// Enemy pieces not defended by a pawn and under our attack
- const Bitboard weakEnemies = pos.pieces(Them)
- & ~ei.attackedBy[Them][PAWN]
- & ei.attackedBy[Us][0];
+ weakEnemies = pos.pieces(Them)
+ & ~ei.attackedBy[Them][PAWN]
+ & ei.attackedBy[Us][0];
+
if (!weakEnemies)
return score;
int attackUnits;
const Square ksq = pos.king_square(Us);
- // King shelter
- Score score = ei.pi->king_shelter<Us>(pos, ksq);
+ // King shelter and enemy pawns storm
+ Score score = ei.pi->king_safety<Us>(pos, ksq);
// King safety. This is quite complicated, and is almost certainly far
// from optimally tuned.
attackUnits = std::min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
+ 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount<Max15>(undefended))
+ InitKingDanger[relative_square(Us, ksq)]
- - mg_value(ei.pi->king_shelter<Us>(pos, ksq)) / 32;
+ - mg_value(ei.pi->king_safety<Us>(pos, ksq)) / 32;
// Analyse enemy's safe queen contact checks. First find undefended
// squares around the king attacked by enemy queen...
ebonus -= Value(square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * rr);
// If the pawn is free to advance, increase bonus
- if (pos.square_is_empty(blockSq))
+ if (pos.square_empty(blockSq))
{
squaresToQueen = squares_in_front_of(Us, s);
defendedSquares = squaresToQueen & ei.attackedBy[Us][0];
}
- // apply_weight() applies an evaluation weight to a value trying to prevent overflow
-
- inline Score apply_weight(Score v, Score w) {
- return make_score((int(mg_value(v)) * mg_value(w)) / 0x100,
- (int(eg_value(v)) * eg_value(w)) / 0x100);
- }
-
-
- // scale_by_game_phase() interpolates between a middle game and an endgame score,
+ // interpolate() interpolates between a middle game and an endgame score,
// based on game phase. It also scales the return value by a ScaleFactor array.
- Value scale_by_game_phase(const Score& v, Phase ph, ScaleFactor sf) {
+ Value interpolate(const Score& v, Phase ph, ScaleFactor sf) {
assert(mg_value(v) > -VALUE_INFINITE && mg_value(v) < VALUE_INFINITE);
assert(eg_value(v) > -VALUE_INFINITE && eg_value(v) < VALUE_INFINITE);