X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=b47570e86303863cc968e632ca49b15ca9e175b0;hp=c915fbfaaad9b022fd700b36841894bd5179dcb2;hb=0a1f54975fe3cb59a5274cbfee51f5b53e64071b;hpb=5605cc7684a7bfbab912482cbb43c73df511063f diff --git a/src/evaluate.cpp b/src/evaluate.cpp index c915fbfa..b47570e8 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -27,7 +27,6 @@ #include "material.h" #include "pawns.h" #include "thread.h" -#include "uci.h" namespace { @@ -58,9 +57,8 @@ namespace { // kingAttackersWeight[color] is the sum of the "weight" of the pieces of the // given color which attack a square in the kingRing of the enemy king. The - // weights of the individual piece types are given by the variables - // QueenAttackWeight, RookAttackWeight, BishopAttackWeight and - // KnightAttackWeight in evaluate.cpp + // weights of the individual piece types are given by the elements in the + // KingAttackWeights array. int kingAttackersWeight[COLOR_NB]; // kingAdjacentZoneAttacksCount[color] is the number of attacks to squares @@ -138,30 +136,32 @@ namespace { V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0) } }; - // Threat[attacking][attacked] contains bonuses according to which piece - // type attacks which one. - const Score Threat[][PIECE_TYPE_NB] = { - { S(0, 0), S(0, 38), S(32, 45), S(32, 45), S(41,100), S(35,104) }, // Minor - { S(0, 0), S(7, 28), S(20, 49), S(20, 49), S(8 , 42), S(23, 44) } // Major + // Threat[defended/weak][minor/major attacking][attacked PieceType] contains + // bonuses according to which piece type attacks which one. + const Score Threat[][2][PIECE_TYPE_NB] = { + { { S(0, 0), S( 0, 0), S(19, 37), S(24, 37), S(44, 97), S(35,106) }, // Defended Minor + { S(0, 0), S( 0, 0), S( 9, 14), S( 9, 14), S( 7, 14), S(24, 48) } }, // Defended Major + { { S(0, 0), S( 0,32), S(33, 41), S(31, 50), S(41,100), S(35,104) }, // Weak Minor + { S(0, 0), S( 0,27), S(26, 57), S(26, 57), S(0 , 43), S(23, 51) } } // Weak Major }; // ThreatenedByPawn[PieceType] contains a penalty according to which piece // type is attacked by an enemy pawn. const Score ThreatenedByPawn[] = { - S(0, 0), S(0, 0), S(80, 119), S(80, 119), S(117, 199), S(127, 218) + S(0, 0), S(0, 0), S(87, 118), S(84, 122), S(114, 203), S(121, 217) }; // Assorted bonuses and penalties used by evaluation - const Score KingOnOne = S(2 , 58); - const Score KingOnMany = S(6 ,125); - const Score RookOnPawn = S(10, 28); + 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(23, 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 @@ -199,8 +199,6 @@ namespace { // scores, indexed by a calculated integer number. Score KingDanger[128]; - const int ScalePawnSpan[2] = { 38, 56 }; - // 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); @@ -222,7 +220,7 @@ namespace { ei.attackedBy[Us][ALL_PIECES] = ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); // Init king safety tables only if we are going to use them - if (pos.non_pawn_material(Us) > QueenValueMg + PawnValueMg) + if (pos.non_pawn_material(Us) >= QueenValueMg) { ei.kingRing[Them] = b | shift_bb(b); b &= ei.attackedBy[Us][PAWN]; @@ -491,22 +489,6 @@ namespace { } - // max_piece_type() is a helper function used by evaluate_threats() to get - // the value of the biggest PieceType of color C in 'target' bitboard. - - template - inline PieceType max_piece_type(const Position& pos, const Bitboard target) { - - assert(target & (pos.pieces(C) ^ pos.pieces(C, KING))); - - for (PieceType pt = QUEEN; pt > PAWN; --pt) - if (target & pos.pieces(C, pt)) - return pt; - - return PAWN; - } - - // evaluate_threats() assigns bonuses according to the type of attacking piece // and the type of attacked one. @@ -515,40 +497,50 @@ namespace { const Color Them = (Us == WHITE ? BLACK : WHITE); + enum { Defended, Weak }; enum { Minor, Major }; - Bitboard b, weakEnemies, protectedEnemies; + Bitboard b, weak, defended; Score score = SCORE_ZERO; - // Enemies defended by a pawn and under our attack by a minor piece - protectedEnemies = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) - & ei.attackedBy[Them][PAWN] - & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + // Non-pawn enemies defended by a pawn and under our attack + defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) + & ei.attackedBy[Them][PAWN] + & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]); - if (protectedEnemies) - score += Threat[Minor][max_piece_type(pos, protectedEnemies)]; + // Add a bonus according to the kind of attacking pieces + if (defended) + { + b = defended & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + while (b) + score += Threat[Defended][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; + + b = defended & (ei.attackedBy[Us][ROOK]); + while (b) + score += Threat[Defended][Major][type_of(pos.piece_on(pop_lsb(&b)))]; + } // Enemies not defended by a pawn and under our attack - weakEnemies = pos.pieces(Them) - & ~ei.attackedBy[Them][PAWN] - & ei.attackedBy[Us][ALL_PIECES]; + weak = pos.pieces(Them) + & ~ei.attackedBy[Them][PAWN] + & ei.attackedBy[Us][ALL_PIECES]; - // Add a bonus according if the attacking pieces are minor or major - if (weakEnemies) + // Add a bonus according to the kind of attacking pieces + if (weak) { - b = weakEnemies & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); - if (b) - score += Threat[Minor][max_piece_type(pos, b)]; + b = weak & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + while (b) + score += Threat[Weak][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weakEnemies & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]); - if (b) - score += Threat[Major][max_piece_type(pos, b)]; + b = weak & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]); + while (b) + score += Threat[Weak][Major][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weakEnemies & ~ei.attackedBy[Them][ALL_PIECES]; + b = weak & ~ei.attackedBy[Them][ALL_PIECES]; if (b) score += more_than_one(b) ? Hanging * popcount(b) : Hanging; - b = weakEnemies & ei.attackedBy[Us][KING]; + b = weak & ei.attackedBy[Us][KING]; if (b) score += more_than_one(b) ? KingOnMany : KingOnOne; } @@ -589,12 +581,12 @@ namespace { Square blockSq = s + pawn_push(Us); // Adjust bonus based on the king's proximity - ebonus += square_distance(pos.king_square(Them), blockSq) * 5 * rr - - square_distance(pos.king_square(Us ), blockSq) * 2 * rr; + ebonus += distance(pos.king_square(Them), blockSq) * 5 * rr + - distance(pos.king_square(Us ), blockSq) * 2 * rr; // If blockSq is not the queening square then consider also a second push if (relative_rank(Us, blockSq) != RANK_8) - ebonus -= square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * rr; + ebonus -= distance(pos.king_square(Us), blockSq + pawn_push(Us)) * rr; // If the pawn is free to advance, then increase the bonus if (pos.empty(blockSq)) @@ -766,27 +758,25 @@ namespace { if ( ei.mi->game_phase() < PHASE_MIDGAME && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) { - if (pos.opposite_bishops()) { - // Ignoring any pawns, do both sides only have a single bishop and no - // other pieces? + if (pos.opposite_bishops()) + { + // Endgame with opposite-colored bishops and no other pieces (ignoring pawns) + // is almost a draw, in case of KBP vs KB is even more a draw. 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); - } + sf = more_than_one(pos.pieces(PAWN)) ? ScaleFactor(32) : ScaleFactor(8); + + // Endgame with opposite-colored bishops, but also other pieces. Still + // a bit drawish, but not as drawish as with only the two bishops. 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); - } else if ( abs(eg_value(score)) <= BishopValueEg - && ei.pi->pawn_span(strongSide) <= 1 - && !pos.pawn_passed(~strongSide, pos.king_square(~strongSide))) { - // Endings where weaker side can be place his king in front of the opponent's pawns are drawish. - sf = ScaleFactor(ScalePawnSpan[ei.pi->pawn_span(strongSide)]); } + // Endings where weaker side can place his king in front of the opponent's + // pawns are drawish. + else if ( abs(eg_value(score)) <= BishopValueEg + && ei.pi->pawn_span(strongSide) <= 1 + && !pos.pawn_passed(~strongSide, pos.king_square(~strongSide))) + sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(56) : ScaleFactor(38); } // Interpolate between a middlegame and a (scaled by 'sf') endgame score @@ -905,8 +895,7 @@ namespace Eval { } - /// init() computes evaluation weights from the corresponding UCI parameters - /// and setup king tables. + /// init() computes evaluation weights. void init() {