From 6933f05f4b1b7b1bd2c072029bf5a06cbeac5b0b Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Sat, 27 Dec 2014 10:47:21 +0100 Subject: [PATCH 1/1] Use score and value consistently And other assorted small fixing, code style tweaks and reshuffles in evaluate.cpp No functional change. --- src/evaluate.cpp | 176 ++++++++++++++++++++++------------------------- src/material.cpp | 2 +- src/material.h | 4 +- src/pawns.cpp | 18 ++--- src/pawns.h | 4 +- 5 files changed, 98 insertions(+), 106 deletions(-) diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 38f2d604..85ac0dab 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -94,7 +94,7 @@ namespace { {289, 344}, {233, 201}, {221, 273}, {46, 0}, {318, 0} }; - typedef Value V; + #define V(v) Value(v) #define S(mg, eg) make_score(mg, eg) // MobilityBonus[PieceType][attacked] contains bonuses for middle and end @@ -152,16 +152,16 @@ namespace { }; // Assorted bonuses and penalties used by evaluation - const Score KingOnOne = S( 2, 58); - const Score KingOnMany = S( 6,125); - const Score RookOnPawn = S( 7, 27); - const Score RookOpenFile = S(43, 21); - const Score RookSemiOpenFile = S(19, 10); - const Score BishopPawns = S( 8, 12); - const Score MinorBehindPawn = S(16, 0); - const Score TrappedRook = S(92, 0); - const Score Unstoppable = S( 0, 20); - const Score Hanging = S(31, 26); + const Score KingOnOne = S( 2, 58); + const Score KingOnMany = S( 6,125); + const Score RookOnPawn = S( 7, 27); + const Score RookOnOpenFile = S(43, 21); + const Score RookOnSemiOpenFile = S(19, 10); + const Score BishopPawns = S( 8, 12); + const Score MinorBehindPawn = S(16, 0); + const Score TrappedRook = S(92, 0); + const Score Unstoppable = S( 0, 20); + const Score Hanging = S(31, 26); // Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only @@ -169,6 +169,7 @@ namespace { const Score TrappedBishopA1H1 = S(50, 50); #undef S + #undef V // SpaceMask[Color] contains the area of the board which is considered // by the space evaluation. In the middlegame, each side is given a bonus @@ -179,8 +180,8 @@ namespace { (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank7BB | Rank6BB | Rank5BB) }; - // King danger constants and variables. The king danger scores are taken - // from KingDanger[]. Various little "meta-bonuses" measuring the strength + // King danger constants and variables. The king danger scores are looked-up + // in KingDanger[]. Various little "meta-bonuses" measuring the strength // of the enemy attack are added up into an integer, which is used as an // index to KingDanger[]. // @@ -199,9 +200,9 @@ namespace { // scores, indexed by a calculated integer number. Score KingDanger[128]; - // apply_weight() weighs score 'v' by weight 'w' trying to prevent overflow - Score apply_weight(Score v, const Weight& w) { - return make_score(mg_value(v) * w.mg / 256, eg_value(v) * w.eg / 256); + // apply_weight() weighs score 's' by weight 'w' trying to prevent overflow + Score apply_weight(Score s, const Weight& w) { + return make_score(mg_value(s) * w.mg / 256, eg_value(s) * w.eg / 256); } @@ -312,65 +313,65 @@ namespace { if (Pt == BISHOP || Pt == KNIGHT) { - // Penalty for bishop with same colored pawns - if (Pt == BISHOP) - score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s); - - // Bishop and knight outpost square + // Bonus for outpost square if (!(pos.pieces(Them, PAWN) & pawn_attack_span(Us, s))) score += evaluate_outpost(pos, ei, s); - // Bishop or knight behind a pawn + // Bonus when behind a pawn if ( relative_rank(Us, s) < RANK_5 && (pos.pieces(PAWN) & (s + pawn_push(Us)))) score += MinorBehindPawn; + + // Penalty for pawns on same color square of bishop + if (Pt == BISHOP) + score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s); + + // An important Chess960 pattern: A cornered bishop blocked by a friendly + // pawn diagonally in front of it is a very serious problem, especially + // when that pawn is also blocked. + if ( Pt == BISHOP + && pos.is_chess960() + && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) + { + Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W); + if (pos.piece_on(s + d) == make_piece(Us, PAWN)) + score -= !pos.empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1 * 4 + : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? TrappedBishopA1H1 * 2 + : TrappedBishopA1H1; + } } if (Pt == ROOK) { - // Rook piece attacking enemy pawns on the same rank/file + // Bonus for aligning with enemy pawns on the same rank/file if (relative_rank(Us, s) >= RANK_5) { - Bitboard pawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; - if (pawns) - score += popcount(pawns) * RookOnPawn; + Bitboard alignedPawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; + if (alignedPawns) + score += popcount(alignedPawns) * RookOnPawn; } - // Give a bonus for a rook on a open or semi-open file + // Bonus when on an open or semi-open file if (ei.pi->semiopen_file(Us, file_of(s))) - score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOpenFile : RookSemiOpenFile; - - if (mob > 3 || ei.pi->semiopen_file(Us, file_of(s))) - continue; - - Square ksq = pos.king_square(Us); + score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOnOpenFile : RookOnSemiOpenFile; - // Penalize rooks which are trapped by a king. Penalize more if the - // king has lost its castling capability. - if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) - && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1) - && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) - score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us)); - } + // Penalize when trapped by the king, even more if king cannot castle + if (mob <= 3 && !ei.pi->semiopen_file(Us, file_of(s))) + { + Square ksq = pos.king_square(Us); - // An important Chess960 pattern: A cornered bishop blocked by a friendly - // pawn diagonally in front of it is a very serious problem, especially - // when that pawn is also blocked. - if ( Pt == BISHOP - && pos.is_chess960() - && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) - { - Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W); - if (pos.piece_on(s + d) == make_piece(Us, PAWN)) - score -= !pos.empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1 * 4 - : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? TrappedBishopA1H1 * 2 - : TrappedBishopA1H1; + if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) + && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1) + && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) + score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us)); + } } } if (Trace) Tracing::write(Pt, Us, score); + // Recursively call evaluate_pieces() of next piece type until KING excluded return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } @@ -406,7 +407,7 @@ namespace { | ei.attackedBy[Us][QUEEN]); // Initialize the 'attackUnits' variable, which is used later on as an - // index to the KingDanger[] array. The initial value is based on the + // index into the KingDanger[] array. The initial value is based on the // number and types of the enemy's attacking pieces, the number of // attacked and undefended squares around our king and the quality of // the pawn shelter (current 'score' value). @@ -417,22 +418,20 @@ namespace { - !pos.count(Them) * 15; // Analyse the enemy's safe queen contact checks. Firstly, find the - // undefended squares around the king that are attacked by the enemy's - // queen... + // undefended squares around the king reachable by the enemy queen... b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them); if (b) { // ...and then remove squares not supported by another enemy piece - b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] - | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]); + b &= ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]; if (b) - attackUnits += QueenContactCheck * popcount(b); + attackUnits += QueenContactCheck * popcount(b); } // Analyse the enemy's safe rook contact checks. Firstly, find the - // undefended squares around the king that are attacked by the enemy's - // rooks... + // undefended squares around the king reachable by the enemy rooks... b = undefended & ei.attackedBy[Them][ROOK] & ~pos.pieces(Them); // Consider only squares where the enemy's rook gives check @@ -445,13 +444,13 @@ namespace { | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][QUEEN]); if (b) - attackUnits += RookContactCheck * popcount(b); + attackUnits += RookContactCheck * popcount(b); } // Analyse the enemy's safe distance checks for sliders and knights - safe = ~(pos.pieces(Them) | ei.attackedBy[Us][ALL_PIECES]); + safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); - b1 = pos.attacks_from(ksq) & safe; + b1 = pos.attacks_from(ksq) & safe; b2 = pos.attacks_from(ksq) & safe; // Enemy queen safe checks @@ -474,12 +473,9 @@ namespace { if (b) attackUnits += KnightCheck * popcount(b); - // To index KingDanger[] attackUnits must be in [0, 99] range - attackUnits = std::min(99, std::max(0, attackUnits)); - // Finally, extract the king danger score from the KingDanger[] // array and subtract the score from evaluation. - score -= KingDanger[attackUnits]; + score -= KingDanger[std::max(std::min(attackUnits, 99), 0)]; } if (Trace) @@ -635,18 +631,6 @@ namespace { } - // evaluate_unstoppable_pawns() scores the most advanced passed pawn. In case - // both players have no pieces but pawns, this is somewhat related to the - // possibility that pawns are unstoppable. - - Score evaluate_unstoppable_pawns(Color us, const EvalInfo& ei) { - - Bitboard b = ei.pi->passed_pawns(us); - - return b ? Unstoppable * int(relative_rank(us, frontmost_sq(us, b))) : SCORE_ZERO; - } - - // evaluate_space() computes the space evaluation for a given side. The // space evaluation is a simple bonus based on the number of safe squares // available for minor pieces on the central four files on ranks 2--4. Safe @@ -654,7 +638,7 @@ namespace { // twice. Finally, the space bonus is scaled by a weight taken from the // material hash table. The aim is to improve play on game opening. template - int evaluate_space(const Position& pos, const EvalInfo& ei) { + Score evaluate_space(const Position& pos, const EvalInfo& ei, Score weight) { const Color Them = (Us == WHITE ? BLACK : WHITE); @@ -675,7 +659,7 @@ namespace { assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0); // Count safe + (behind & safe) with a single popcount - return popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); + return popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)) * weight; } @@ -697,7 +681,7 @@ namespace { // Probe the material hash table ei.mi = Material::probe(pos, thisThread->materialTable, thisThread->endgames); - score += ei.mi->material_value(); + score += ei.mi->imbalance(); // If we have a specialized evaluation function for the current material // configuration, call it and return. @@ -706,7 +690,7 @@ namespace { // Probe the pawn hash table ei.pi = Pawns::probe(pos, thisThread->pawnsTable); - score += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); + score += apply_weight(ei.pi->pawns_score(), Weights[PawnStructure]); // Initialize attack and king safety bitboards init_eval_info(pos, ei); @@ -738,14 +722,22 @@ namespace { // If both sides have only pawns, score for potential unstoppable pawns if (!pos.non_pawn_material(WHITE) && !pos.non_pawn_material(BLACK)) - score += evaluate_unstoppable_pawns(WHITE, ei) - - evaluate_unstoppable_pawns(BLACK, ei); + { + Bitboard b; + if ((b = ei.pi->passed_pawns(WHITE)) != 0) + score += int(relative_rank(WHITE, frontmost_sq(WHITE, b))) * Unstoppable; + + if ((b = ei.pi->passed_pawns(BLACK)) != 0) + score -= int(relative_rank(BLACK, frontmost_sq(BLACK, b))) * Unstoppable; + } // Evaluate space for both sides, only in middlegame if (ei.mi->space_weight()) { - int s = evaluate_space(pos, ei) - evaluate_space(pos, ei); - score += apply_weight(s * ei.mi->space_weight(), Weights[Space]); + Score s = evaluate_space(pos, ei, ei.mi->space_weight()) + - evaluate_space(pos, ei, ei.mi->space_weight()); + + score += apply_weight(s, Weights[Space]); } // Scale winning side if position is more drawish than it appears @@ -788,12 +780,12 @@ namespace { if (Trace) { Tracing::write(Tracing::MATERIAL, pos.psq_score()); - Tracing::write(Tracing::IMBALANCE, ei.mi->material_value()); - Tracing::write(PAWN, ei.pi->pawns_value()); + Tracing::write(Tracing::IMBALANCE, ei.mi->imbalance()); + Tracing::write(PAWN, ei.pi->pawns_score()); Tracing::write(Tracing::MOBILITY, apply_weight(mobility[WHITE], Weights[Mobility]) , apply_weight(mobility[BLACK], Weights[Mobility])); - Score w = ei.mi->space_weight() * evaluate_space(pos, ei); - Score b = ei.mi->space_weight() * evaluate_space(pos, ei); + Score w = evaluate_space(pos, ei, ei.mi->space_weight()); + Score b = evaluate_space(pos, ei, ei.mi->space_weight()); Tracing::write(Tracing::SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space])); Tracing::write(Tracing::TOTAL, score); Tracing::ei = ei; @@ -894,7 +886,7 @@ namespace Eval { } - /// init() computes evaluation weights. + /// init() computes evaluation weights, usually at startup void init() { diff --git a/src/material.cpp b/src/material.cpp index a14e3370..7047afb1 100644 --- a/src/material.cpp +++ b/src/material.cpp @@ -27,7 +27,7 @@ using namespace std; namespace { - // Polynomial material balance parameters + // Polynomial material imbalance parameters // pair pawn knight bishop rook queen const int Linear[6] = { 1852, -162, -1122, -183, 249, -154 }; diff --git a/src/material.h b/src/material.h index f05541cc..754d0523 100644 --- a/src/material.h +++ b/src/material.h @@ -28,7 +28,7 @@ namespace Material { /// Material::Entry contains various information about a material configuration. -/// It contains a material balance evaluation, a function pointer to a special +/// It contains a material imbalance evaluation, a function pointer to a special /// endgame evaluation function (which in most cases is NULL, meaning that the /// standard evaluation function will be used), and "scale factors". /// @@ -38,7 +38,7 @@ namespace Material { struct Entry { - Score material_value() const { return make_score(value, value); } + Score imbalance() const { return make_score(value, value); } Score space_weight() const { return spaceWeight; } Phase game_phase() const { return gamePhase; } bool specialized_eval_exists() const { return evaluationFunction != NULL; } diff --git a/src/pawns.cpp b/src/pawns.cpp index b26b1be6..3d98c012 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -104,7 +104,7 @@ namespace { Bitboard b, p, doubled, connected; Square s; bool passed, isolated, opposed, phalanx, backward, unsupported, lever; - Score value = SCORE_ZERO; + Score score = SCORE_ZERO; const Square* pl = pos.list(Us); const Bitboard* pawnAttacksBB = StepAttacksBB[make_piece(Us, PAWN)]; @@ -174,28 +174,28 @@ namespace { // Score this pawn if (isolated) - value -= Isolated[opposed][f]; + score -= Isolated[opposed][f]; if (unsupported && !isolated) - value -= UnsupportedPawnPenalty; + score -= UnsupportedPawnPenalty; if (doubled) - value -= Doubled[f] / distance(s, frontmost_sq(Us, doubled)); + score -= Doubled[f] / distance(s, frontmost_sq(Us, doubled)); if (backward) - value -= Backward[opposed][f]; + score -= Backward[opposed][f]; if (connected) - value += Connected[opposed][phalanx][relative_rank(Us, s)]; + score += Connected[opposed][phalanx][relative_rank(Us, s)]; if (lever) - value += Lever[relative_rank(Us, s)]; + score += Lever[relative_rank(Us, s)]; } b = e->semiopenFiles[Us] ^ 0xFF; e->pawnSpan[Us] = b ? int(msb(b) - lsb(b)) : 0; - return value; + return score; } } // namespace @@ -233,7 +233,7 @@ Entry* probe(const Position& pos, Table& entries) { return e; e->key = key; - e->value = evaluate(pos, e) - evaluate(pos, e); + e->score = evaluate(pos, e) - evaluate(pos, e); return e; } diff --git a/src/pawns.h b/src/pawns.h index 807e1b09..04aced77 100644 --- a/src/pawns.h +++ b/src/pawns.h @@ -32,7 +32,7 @@ namespace Pawns { struct Entry { - Score pawns_value() const { return value; } + Score pawns_score() const { return score; } Bitboard pawn_attacks(Color c) const { return pawnAttacks[c]; } Bitboard passed_pawns(Color c) const { return passedPawns[c]; } @@ -65,7 +65,7 @@ struct Entry { Value shelter_storm(const Position& pos, Square ksq); Key key; - Score value; + Score score; Bitboard passedPawns[COLOR_NB]; Bitboard pawnAttacks[COLOR_NB]; Square kingSquares[COLOR_NB]; -- 2.39.2