X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=121f2c603293845e3b2ff29998a9e4a4e8c89fbb;hp=3228c9a129df5e84903d2984e7e581a24482f07c;hb=2f92e3b5251e8da1c573a9860b8f42afca4f9366;hpb=0510112f9184db3be86492267a4564035f954ec6 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 3228c9a1..121f2c60 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -206,199 +206,37 @@ namespace { // scores, indexed by color and by a calculated integer number. Score KingDanger[COLOR_NB][128]; - // Function prototypes - template - Value do_evaluate(const Position& pos); - - template - void init_eval_info(const Position& pos, EvalInfo& ei); - - template - Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility, Bitboard* mobilityArea); - - template - Score evaluate_king(const Position& pos, const EvalInfo& ei); - - template - Score evaluate_threats(const Position& pos, const EvalInfo& ei); - template - Score evaluate_passed_pawns(const Position& pos, const EvalInfo& ei); - - template - int evaluate_space(const Position& pos, const EvalInfo& ei); - - Score evaluate_unstoppable_pawns(const Position& pos, Color us, const EvalInfo& ei); - - Value interpolate(const Score& v, Phase ph, ScaleFactor sf); - Score apply_weight(Score v, const Weight& w); - Weight weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight); -} - - -namespace Eval { - - /// evaluate() is the main evaluation function. It always computes two - /// values, an endgame score and a middlegame score, and interpolates - /// between them based on the remaining material. - - Value evaluate(const Position& pos) { - return do_evaluate(pos); - } - - - /// trace() is like evaluate(), but instead of returning a value, it returns - /// a string (suitable for outputting to stdout) that contains the detailed - /// descriptions and values of each evaluation term. It's mainly used for - /// debugging. - std::string trace(const Position& pos) { - return Tracing::do_trace(pos); + // apply_weight() weights score v by score 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); } - /// init() computes evaluation weights from the corresponding UCI parameters - /// and setup king tables. - - void init() { - - Weights[Mobility] = weight_option("Mobility (Midgame)", "Mobility (Endgame)", WeightsInternal[Mobility]); - Weights[PawnStructure] = weight_option("Pawn Structure (Midgame)", "Pawn Structure (Endgame)", WeightsInternal[PawnStructure]); - Weights[PassedPawns] = weight_option("Passed Pawns (Midgame)", "Passed Pawns (Endgame)", WeightsInternal[PassedPawns]); - Weights[Space] = weight_option("Space", "Space", WeightsInternal[Space]); - Weights[KingDangerUs] = weight_option("Cowardice", "Cowardice", WeightsInternal[KingDangerUs]); - Weights[KingDangerThem] = weight_option("Aggressiveness", "Aggressiveness", WeightsInternal[KingDangerThem]); - - const int MaxSlope = 30; - const int Peak = 1280; + // weight_option() computes the value of an evaluation weight, by combining + // two UCI-configurable weights (midgame and endgame) with an internal weight. - for (int t = 0, i = 1; i < 100; ++i) - { - t = std::min(Peak, std::min(int(0.4 * i * i), t + MaxSlope)); + Weight weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) { - KingDanger[1][i] = apply_weight(make_score(t, 0), Weights[KingDangerUs]); - KingDanger[0][i] = apply_weight(make_score(t, 0), Weights[KingDangerThem]); - } + Weight w = { Options[mgOpt] * mg_value(internalWeight) / 100, + Options[egOpt] * eg_value(internalWeight) / 100 }; + return w; } -} // namespace Eval - - -namespace { - -template -Value do_evaluate(const Position& pos) { - assert(!pos.checkers()); - - EvalInfo ei; - Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; - Thread* thisThread = pos.this_thread(); - - // Initialize score by reading the incrementally updated scores included - // in the position object (material + piece square tables) and adding a - // 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 = Material::probe(pos, thisThread->materialTable, thisThread->endgames); - score += ei.mi->material_value(); - - // If we have a specialized evaluation function for the current material - // configuration, call it and return. - if (ei.mi->specialized_eval_exists()) - return ei.mi->evaluate(pos); - - // Probe the pawn hash table - ei.pi = Pawns::probe(pos, thisThread->pawnsTable); - score += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); - - // Initialize attack and king safety bitboards - init_eval_info(pos, ei); - init_eval_info(pos, ei); - - ei.attackedBy[WHITE][ALL_PIECES] |= ei.attackedBy[WHITE][KING]; - ei.attackedBy[BLACK][ALL_PIECES] |= ei.attackedBy[BLACK][KING]; - - // Do not include in mobility squares protected by enemy pawns or occupied by our pieces - Bitboard mobilityArea[] = { ~(ei.attackedBy[BLACK][PAWN] | pos.pieces(WHITE, PAWN, KING)), - ~(ei.attackedBy[WHITE][PAWN] | pos.pieces(BLACK, PAWN, KING)) }; - - // Evaluate pieces and mobility - score += evaluate_pieces(pos, ei, mobility, mobilityArea); - score += apply_weight(mobility[WHITE] - mobility[BLACK], Weights[Mobility]); - - // Evaluate kings after all other pieces because we need complete attack - // information when computing the king safety evaluation. - score += evaluate_king(pos, ei) - - evaluate_king(pos, ei); - - // Evaluate tactical threats, we need full attack information including king - score += evaluate_threats(pos, ei) - - evaluate_threats(pos, ei); - - // Evaluate passed pawns, we need full attack information including king - score += evaluate_passed_pawns(pos, ei) - - evaluate_passed_pawns(pos, ei); - - // If one side has only a king, score for potential unstoppable pawns - if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK)) - score += evaluate_unstoppable_pawns(pos, WHITE, ei) - - evaluate_unstoppable_pawns(pos, BLACK, ei); - - // 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]); - } - - // Scale winning side if position is more drawish than it appears - ScaleFactor sf = eg_value(score) > VALUE_DRAW ? ei.mi->scale_factor(pos, WHITE) - : ei.mi->scale_factor(pos, BLACK); + // interpolate() interpolates between a middlegame and an endgame score, + // based on game phase. It also scales the return value by a ScaleFactor array. - // 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_bishops() - && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) - { - // Ignoring any pawns, do both sides only have a single bishop and no - // other pieces? - if ( pos.non_pawn_material(WHITE) == BishopValueMg - && pos.non_pawn_material(BLACK) == BishopValueMg) - { - // Check for KBP vs KB with only a single pawn that is almost - // certainly a draw or at least two pawns. - bool one_pawn = (pos.count(WHITE) + pos.count(BLACK) == 1); - sf = one_pawn ? ScaleFactor(8) : ScaleFactor(32); - } - else - // Endgame with opposite-colored bishops, but also other pieces. Still - // a bit drawish, but not as drawish as with only the two bishops. - sf = ScaleFactor(50 * sf / SCALE_FACTOR_NORMAL); - } + Value interpolate(const Score& v, Phase ph, ScaleFactor sf) { - Value v = interpolate(score, ei.mi->game_phase(), sf); + assert(-VALUE_INFINITE < mg_value(v) && mg_value(v) < VALUE_INFINITE); + assert(-VALUE_INFINITE < eg_value(v) && eg_value(v) < VALUE_INFINITE); + assert(PHASE_ENDGAME <= ph && ph <= PHASE_MIDGAME); - // In case of tracing add all single evaluation contributions for both white and black - if (Trace) - { - Tracing::add_term(Tracing::PST, pos.psq_score()); - Tracing::add_term(Tracing::IMBALANCE, ei.mi->material_value()); - Tracing::add_term(PAWN, ei.pi->pawns_value()); - Tracing::add_term(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); - Tracing::add_term(Tracing::SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space])); - Tracing::add_term(Tracing::TOTAL, score); - Tracing::ei = ei; - Tracing::sf = sf; + int eg = (eg_value(v) * int(sf)) / SCALE_FACTOR_NORMAL; + return Value((mg_value(v) * int(ph) + eg * int(PHASE_MIDGAME - ph)) / PHASE_MIDGAME); } - return pos.side_to_move() == WHITE ? v : -v; -} - // init_eval_info() initializes king bitboards for given color adding // pawn attacks. To be done at the beginning of the evaluation. @@ -463,6 +301,7 @@ Value do_evaluate(const Position& pos) { Square s; Score score = SCORE_ZERO; + const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); const Color Them = (Us == WHITE ? BLACK : WHITE); const Square* pl = pos.list(Us); @@ -574,8 +413,6 @@ Value do_evaluate(const Position& pos) { if (Trace) Tracing::terms[Us][Pt] = score; - const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); - return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } @@ -899,33 +736,120 @@ Value do_evaluate(const Position& pos) { } - // interpolate() interpolates between a middlegame and an endgame score, - // based on game phase. It also scales the return value by a ScaleFactor array. + // do_evaluate() is the evaluation entry point, called directly from evaluate() - Value interpolate(const Score& v, Phase ph, ScaleFactor sf) { + template + Value do_evaluate(const Position& pos) { - assert(-VALUE_INFINITE < mg_value(v) && mg_value(v) < VALUE_INFINITE); - assert(-VALUE_INFINITE < eg_value(v) && eg_value(v) < VALUE_INFINITE); - assert(PHASE_ENDGAME <= ph && ph <= PHASE_MIDGAME); + assert(!pos.checkers()); - int eg = (eg_value(v) * int(sf)) / SCALE_FACTOR_NORMAL; - return Value((mg_value(v) * int(ph) + eg * int(PHASE_MIDGAME - ph)) / PHASE_MIDGAME); - } + EvalInfo ei; + Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; + Thread* thisThread = pos.this_thread(); + + // Initialize score by reading the incrementally updated scores included + // in the position object (material + piece square tables) and adding a + // 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 = Material::probe(pos, thisThread->materialTable, thisThread->endgames); + score += ei.mi->material_value(); + + // If we have a specialized evaluation function for the current material + // configuration, call it and return. + if (ei.mi->specialized_eval_exists()) + return ei.mi->evaluate(pos); + + // Probe the pawn hash table + ei.pi = Pawns::probe(pos, thisThread->pawnsTable); + score += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); + + // Initialize attack and king safety bitboards + init_eval_info(pos, ei); + init_eval_info(pos, ei); + + ei.attackedBy[WHITE][ALL_PIECES] |= ei.attackedBy[WHITE][KING]; + ei.attackedBy[BLACK][ALL_PIECES] |= ei.attackedBy[BLACK][KING]; + + // Do not include in mobility squares protected by enemy pawns or occupied by our pieces + Bitboard mobilityArea[] = { ~(ei.attackedBy[BLACK][PAWN] | pos.pieces(WHITE, PAWN, KING)), + ~(ei.attackedBy[WHITE][PAWN] | pos.pieces(BLACK, PAWN, KING)) }; + + // Evaluate pieces and mobility + score += evaluate_pieces(pos, ei, mobility, mobilityArea); + score += apply_weight(mobility[WHITE] - mobility[BLACK], Weights[Mobility]); + + // Evaluate kings after all other pieces because we need complete attack + // information when computing the king safety evaluation. + score += evaluate_king(pos, ei) + - evaluate_king(pos, ei); + + // Evaluate tactical threats, we need full attack information including king + score += evaluate_threats(pos, ei) + - evaluate_threats(pos, ei); + + // Evaluate passed pawns, we need full attack information including king + score += evaluate_passed_pawns(pos, ei) + - evaluate_passed_pawns(pos, ei); + + // If one side has only a king, score for potential unstoppable pawns + if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK)) + score += evaluate_unstoppable_pawns(pos, WHITE, ei) + - evaluate_unstoppable_pawns(pos, BLACK, ei); + + // 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]); + } - // apply_weight() weights score v by score w trying to prevent overflow - Score apply_weight(Score v, const Weight& w) { + // Scale winning side if position is more drawish than it appears + ScaleFactor sf = eg_value(score) > VALUE_DRAW ? ei.mi->scale_factor(pos, WHITE) + : ei.mi->scale_factor(pos, BLACK); - return make_score(mg_value(v) * w.mg / 256, eg_value(v) * w.eg / 256); - } + // 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_bishops() + && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) + { + // Ignoring any pawns, do both sides only have a single bishop and no + // other pieces? + if ( pos.non_pawn_material(WHITE) == BishopValueMg + && pos.non_pawn_material(BLACK) == BishopValueMg) + { + // Check for KBP vs KB with only a single pawn that is almost + // certainly a draw or at least two pawns. + bool one_pawn = (pos.count(WHITE) + pos.count(BLACK) == 1); + sf = one_pawn ? ScaleFactor(8) : ScaleFactor(32); + } + else + // Endgame with opposite-colored bishops, but also other pieces. Still + // a bit drawish, but not as drawish as with only the two bishops. + sf = ScaleFactor(50 * sf / SCALE_FACTOR_NORMAL); + } - // weight_option() computes the value of an evaluation weight, by combining - // two UCI-configurable weights (midgame and endgame) with an internal weight. + Value v = interpolate(score, ei.mi->game_phase(), sf); - Weight weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) { + // In case of tracing add all single evaluation contributions for both white and black + if (Trace) + { + Tracing::add_term(Tracing::PST, pos.psq_score()); + Tracing::add_term(Tracing::IMBALANCE, ei.mi->material_value()); + Tracing::add_term(PAWN, ei.pi->pawns_value()); + Tracing::add_term(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); + Tracing::add_term(Tracing::SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space])); + Tracing::add_term(Tracing::TOTAL, score); + Tracing::ei = ei; + Tracing::sf = sf; + } - Weight w = { Options[mgOpt] * mg_value(internalWeight) / 100, - Options[egOpt] * eg_value(internalWeight) / 100 }; - return w; + return pos.side_to_move() == WHITE ? v : -v; } @@ -994,4 +918,52 @@ Value do_evaluate(const Position& pos) { return ss.str(); } -} + +} // namespace + + +namespace Eval { + + /// evaluate() is the main evaluation function. It always computes two + /// values, an endgame score and a middlegame score, and interpolates + /// between them based on the remaining material. + + Value evaluate(const Position& pos) { + return do_evaluate(pos); + } + + + /// trace() is like evaluate(), but instead of returning a value, it returns + /// a string (suitable for outputting to stdout) that contains the detailed + /// descriptions and values of each evaluation term. It's mainly used for + /// debugging. + std::string trace(const Position& pos) { + return Tracing::do_trace(pos); + } + + + /// init() computes evaluation weights from the corresponding UCI parameters + /// and setup king tables. + + void init() { + + Weights[Mobility] = weight_option("Mobility (Midgame)", "Mobility (Endgame)", WeightsInternal[Mobility]); + Weights[PawnStructure] = weight_option("Pawn Structure (Midgame)", "Pawn Structure (Endgame)", WeightsInternal[PawnStructure]); + Weights[PassedPawns] = weight_option("Passed Pawns (Midgame)", "Passed Pawns (Endgame)", WeightsInternal[PassedPawns]); + Weights[Space] = weight_option("Space", "Space", WeightsInternal[Space]); + Weights[KingDangerUs] = weight_option("Cowardice", "Cowardice", WeightsInternal[KingDangerUs]); + Weights[KingDangerThem] = weight_option("Aggressiveness", "Aggressiveness", WeightsInternal[KingDangerThem]); + + const int MaxSlope = 30; + const int Peak = 1280; + + for (int t = 0, i = 1; i < 100; ++i) + { + t = std::min(Peak, std::min(int(0.4 * i * i), t + MaxSlope)); + + KingDanger[1][i] = apply_weight(make_score(t, 0), Weights[KingDangerUs]); + KingDanger[0][i] = apply_weight(make_score(t, 0), Weights[KingDangerThem]); + } + } + +} // namespace Eval