2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
6 Stockfish is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 Stockfish is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
30 #include "ucioption.h"
34 // Struct EvalInfo contains various information computed and collected
35 // by the evaluation functions.
38 // Pointers to material and pawn hash table entries
42 // attackedBy[color][piece type] is a bitboard representing all squares
43 // attacked by a given color and piece type, attackedBy[color][0] contains
44 // all squares attacked by the given color.
45 Bitboard attackedBy[2][8];
47 // kingRing[color] is the zone around the king which is considered
48 // by the king safety evaluation. This consists of the squares directly
49 // adjacent to the king, and the three (or two, for a king on an edge file)
50 // squares two ranks in front of the king. For instance, if black's king
51 // is on g8, kingRing[BLACK] is a bitboard containing the squares f8, h8,
52 // f7, g7, h7, f6, g6 and h6.
55 // kingAttackersCount[color] is the number of pieces of the given color
56 // which attack a square in the kingRing of the enemy king.
57 int kingAttackersCount[2];
59 // kingAttackersWeight[color] is the sum of the "weight" of the pieces of the
60 // given color which attack a square in the kingRing of the enemy king. The
61 // weights of the individual piece types are given by the variables
62 // QueenAttackWeight, RookAttackWeight, BishopAttackWeight and
63 // KnightAttackWeight in evaluate.cpp
64 int kingAttackersWeight[2];
66 // kingAdjacentZoneAttacksCount[color] is the number of attacks to squares
67 // directly adjacent to the king of the given color. Pieces which attack
68 // more than one square are counted multiple times. For instance, if black's
69 // king is on g8 and there's a white knight on g5, this knight adds
70 // 2 to kingAdjacentZoneAttacksCount[BLACK].
71 int kingAdjacentZoneAttacksCount[2];
74 // Evaluation grain size, must be a power of 2
75 const int GrainSize = 8;
77 // Evaluation weights, initialized from UCI options
78 enum { Mobility, PassedPawns, Space, KingDangerUs, KingDangerThem };
82 #define S(mg, eg) make_score(mg, eg)
84 // Internal evaluation weights. These are applied on top of the evaluation
85 // weights read from UCI parameters. The purpose is to be able to change
86 // the evaluation weights while keeping the default values of the UCI
87 // parameters at 100, which looks prettier.
89 // Values modified by Joona Kiiski
90 const Score WeightsInternal[] = {
91 S(252, 344), S(216, 266), S(46, 0), S(247, 0), S(259, 0)
94 // MobilityBonus[PieceType][attacked] contains mobility bonuses for middle and
95 // end game, indexed by piece type and number of attacked squares not occupied
96 // by friendly pieces.
97 const Score MobilityBonus[][32] = {
99 { S(-38,-33), S(-25,-23), S(-12,-13), S( 0, -3), S(12, 7), S(25, 17), // Knights
100 S( 31, 22), S( 38, 27), S( 38, 27) },
101 { S(-25,-30), S(-11,-16), S( 3, -2), S(17, 12), S(31, 26), S(45, 40), // Bishops
102 S( 57, 52), S( 65, 60), S( 71, 65), S(74, 69), S(76, 71), S(78, 73),
103 S( 79, 74), S( 80, 75), S( 81, 76), S(81, 76) },
104 { S(-20,-36), S(-14,-19), S( -8, -3), S(-2, 13), S( 4, 29), S(10, 46), // Rooks
105 S( 14, 62), S( 19, 79), S( 23, 95), S(26,106), S(27,111), S(28,114),
106 S( 29,116), S( 30,117), S( 31,118), S(32,118) },
107 { S(-10,-18), S( -8,-13), S( -6, -7), S(-3, -2), S(-1, 3), S( 1, 8), // Queens
108 S( 3, 13), S( 5, 19), S( 8, 23), S(10, 27), S(12, 32), S(15, 34),
109 S( 16, 35), S( 17, 35), S( 18, 35), S(20, 35), S(20, 35), S(20, 35),
110 S( 20, 35), S( 20, 35), S( 20, 35), S(20, 35), S(20, 35), S(20, 35),
111 S( 20, 35), S( 20, 35), S( 20, 35), S(20, 35), S(20, 35), S(20, 35),
112 S( 20, 35), S( 20, 35) }
115 // OutpostBonus[PieceType][Square] contains outpost bonuses of knights and
116 // bishops, indexed by piece type and square (from white's point of view).
117 const Value OutpostBonus[][64] = {
120 V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Knights
121 V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0),
122 V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0),
123 V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0),
124 V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0),
125 V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0) },
127 V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Bishops
128 V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0),
129 V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0),
130 V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0),
131 V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0),
132 V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0) }
135 // ThreatBonus[attacking][attacked] contains threat bonuses according to
136 // which piece type attacks which one.
137 const Score ThreatBonus[][8] = {
139 { S(0, 0), S( 7, 39), S( 0, 0), S(24, 49), S(41,100), S(41,100) }, // KNIGHT
140 { S(0, 0), S( 7, 39), S(24, 49), S( 0, 0), S(41,100), S(41,100) }, // BISHOP
141 { S(0, 0), S( 0, 22), S(15, 49), S(15, 49), S( 0, 0), S(24, 49) }, // ROOK
142 { S(0, 0), S(15, 39), S(15, 39), S(15, 39), S(15, 39), S( 0, 0) } // QUEEN
145 // ThreatenedByPawnPenalty[PieceType] contains a penalty according to which
146 // piece type is attacked by an enemy pawn.
147 const Score ThreatenedByPawnPenalty[] = {
148 S(0, 0), S(0, 0), S(56, 70), S(56, 70), S(76, 99), S(86, 118)
153 // Bonus for having the side to move (modified by Joona Kiiski)
154 const Score Tempo = make_score(24, 11);
156 // Rooks and queens on the 7th rank
157 const Score RookOn7thBonus = make_score(3, 20);
158 const Score QueenOn7thBonus = make_score(1, 8);
160 // Rooks and queens attacking pawns on the same rank
161 const Score RookOnPawnBonus = make_score(3, 48);
162 const Score QueenOnPawnBonus = make_score(1, 40);
164 // Rooks on open files (modified by Joona Kiiski)
165 const Score RookOpenFileBonus = make_score(43, 21);
166 const Score RookHalfOpenFileBonus = make_score(19, 10);
168 // Penalty for rooks trapped inside a friendly king which has lost the
170 const Value TrappedRookPenalty = Value(180);
172 // Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by
173 // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only
174 // happen in Chess960 games.
175 const Score TrappedBishopA1H1Penalty = make_score(100, 100);
177 // Penalty for an undefended bishop or knight
178 const Score UndefendedMinorPenalty = make_score(25, 10);
180 // The SpaceMask[Color] contains the area of the board which is considered
181 // by the space evaluation. In the middle game, each side is given a bonus
182 // based on how many squares inside this area are safe and available for
183 // friendly minor pieces.
184 const Bitboard SpaceMask[] = {
185 (1ULL << SQ_C2) | (1ULL << SQ_D2) | (1ULL << SQ_E2) | (1ULL << SQ_F2) |
186 (1ULL << SQ_C3) | (1ULL << SQ_D3) | (1ULL << SQ_E3) | (1ULL << SQ_F3) |
187 (1ULL << SQ_C4) | (1ULL << SQ_D4) | (1ULL << SQ_E4) | (1ULL << SQ_F4),
188 (1ULL << SQ_C7) | (1ULL << SQ_D7) | (1ULL << SQ_E7) | (1ULL << SQ_F7) |
189 (1ULL << SQ_C6) | (1ULL << SQ_D6) | (1ULL << SQ_E6) | (1ULL << SQ_F6) |
190 (1ULL << SQ_C5) | (1ULL << SQ_D5) | (1ULL << SQ_E5) | (1ULL << SQ_F5)
193 // King danger constants and variables. The king danger scores are taken
194 // from the KingDangerTable[]. Various little "meta-bonuses" measuring
195 // the strength of the enemy attack are added up into an integer, which
196 // is used as an index to KingDangerTable[].
198 // KingAttackWeights[PieceType] contains king attack weights by piece type
199 const int KingAttackWeights[] = { 0, 0, 2, 2, 3, 5 };
201 // Bonuses for enemy's safe checks
202 const int QueenContactCheckBonus = 6;
203 const int RookContactCheckBonus = 4;
204 const int QueenCheckBonus = 3;
205 const int RookCheckBonus = 2;
206 const int BishopCheckBonus = 1;
207 const int KnightCheckBonus = 1;
209 // InitKingDanger[Square] contains penalties based on the position of the
210 // defending king, indexed by king's square (from white's point of view).
211 const int InitKingDanger[] = {
212 2, 0, 2, 5, 5, 2, 0, 2,
213 2, 2, 4, 8, 8, 4, 2, 2,
214 7, 10, 12, 12, 12, 12, 10, 7,
215 15, 15, 15, 15, 15, 15, 15, 15,
216 15, 15, 15, 15, 15, 15, 15, 15,
217 15, 15, 15, 15, 15, 15, 15, 15,
218 15, 15, 15, 15, 15, 15, 15, 15,
219 15, 15, 15, 15, 15, 15, 15, 15
222 // KingDangerTable[Color][attackUnits] contains the actual king danger
223 // weighted scores, indexed by color and by a calculated integer number.
224 Score KingDangerTable[2][128];
226 // TracedTerms[Color][PieceType || TracedType] contains a breakdown of the
227 // evaluation terms, used when tracing.
228 Score TracedScores[2][16];
229 std::stringstream TraceStream;
232 PST = 8, IMBALANCE = 9, MOBILITY = 10, THREAT = 11,
233 PASSED = 12, UNSTOPPABLE = 13, SPACE = 14, TOTAL = 15
236 // Function prototypes
238 Value do_evaluate(const Position& pos, Value& margin);
241 void init_eval_info(const Position& pos, EvalInfo& ei);
243 template<Color Us, bool Trace>
244 Score evaluate_pieces_of_color(const Position& pos, EvalInfo& ei, Score& mobility);
246 template<Color Us, bool Trace>
247 Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]);
250 Score evaluate_threats(const Position& pos, EvalInfo& ei);
253 int evaluate_space(const Position& pos, EvalInfo& ei);
256 Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei);
258 Score evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei);
260 Value interpolate(const Score& v, Phase ph, ScaleFactor sf);
261 Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight);
262 double to_cp(Value v);
263 void trace_add(int idx, Score term_w, Score term_b = SCORE_ZERO);
264 void trace_row(const char* name, int idx);
271 Value ValueDrawContempt;
273 /// evaluate() is the main evaluation function. It always computes two
274 /// values, an endgame score and a middle game score, and interpolates
275 /// between them based on the remaining material.
277 Value evaluate(const Position& pos, Value& margin) {
278 return do_evaluate<false>(pos, margin);
282 /// init() computes evaluation weights from the corresponding UCI parameters
283 /// and setup king tables.
287 Weights[Mobility] = weight_option("Mobility (Middle Game)", "Mobility (Endgame)", WeightsInternal[Mobility]);
288 Weights[PassedPawns] = weight_option("Passed Pawns (Middle Game)", "Passed Pawns (Endgame)", WeightsInternal[PassedPawns]);
289 Weights[Space] = weight_option("Space", "Space", WeightsInternal[Space]);
290 Weights[KingDangerUs] = weight_option("Cowardice", "Cowardice", WeightsInternal[KingDangerUs]);
291 Weights[KingDangerThem] = weight_option("Aggressiveness", "Aggressiveness", WeightsInternal[KingDangerThem]);
293 // King safety is asymmetrical. Our king danger level is weighted by
294 // "Cowardice" UCI parameter, instead the opponent one by "Aggressiveness".
295 // If running in analysis mode, make sure we use symmetrical king safety. We
296 // do this by replacing both Weights[kingDangerUs] and Weights[kingDangerThem]
298 if (Options["UCI_AnalyseMode"])
299 Weights[KingDangerUs] = Weights[KingDangerThem] = (Weights[KingDangerUs] + Weights[KingDangerThem]) / 2;
301 const int MaxSlope = 30;
302 const int Peak = 1280;
304 for (int t = 0, i = 1; i < 100; i++)
306 t = std::min(Peak, std::min(int(0.4 * i * i), t + MaxSlope));
308 KingDangerTable[1][i] = apply_weight(make_score(t, 0), Weights[KingDangerUs]);
309 KingDangerTable[0][i] = apply_weight(make_score(t, 0), Weights[KingDangerThem]);
312 ValueDrawContempt = VALUE_DRAW - Options["Contempt Factor"] * PawnValueMg / 100;
316 /// trace() is like evaluate() but instead of a value returns a string suitable
317 /// to be print on stdout with the detailed descriptions and values of each
318 /// evaluation term. Used mainly for debugging.
320 std::string trace(const Position& pos) {
325 RootColor = pos.side_to_move();
328 TraceStream << std::showpoint << std::showpos << std::fixed << std::setprecision(2);
329 memset(TracedScores, 0, 2 * 16 * sizeof(Score));
331 do_evaluate<true>(pos, margin);
333 totals = TraceStream.str();
336 TraceStream << std::setw(21) << "Eval term " << "| White | Black | Total \n"
337 << " | MG EG | MG EG | MG EG \n"
338 << "---------------------+-------------+-------------+---------------\n";
340 trace_row("Material, PST, Tempo", PST);
341 trace_row("Material imbalance", IMBALANCE);
342 trace_row("Pawns", PAWN);
343 trace_row("Knights", KNIGHT);
344 trace_row("Bishops", BISHOP);
345 trace_row("Rooks", ROOK);
346 trace_row("Queens", QUEEN);
347 trace_row("Mobility", MOBILITY);
348 trace_row("King safety", KING);
349 trace_row("Threats", THREAT);
350 trace_row("Passed pawns", PASSED);
351 trace_row("Unstoppable pawns", UNSTOPPABLE);
352 trace_row("Space", SPACE);
354 TraceStream << "---------------------+-------------+-------------+---------------\n";
355 trace_row("Total", TOTAL);
356 TraceStream << totals;
358 return TraceStream.str();
367 Value do_evaluate(const Position& pos, Value& margin) {
369 assert(!pos.in_check());
373 Score score, mobilityWhite, mobilityBlack;
375 // margins[] store the uncertainty estimation of position's evaluation
376 // that typically is used by the search for pruning decisions.
377 margins[WHITE] = margins[BLACK] = VALUE_ZERO;
379 // Initialize score by reading the incrementally updated scores included
380 // in the position object (material + piece square tables) and adding
381 // Tempo bonus. Score is computed from the point of view of white.
382 score = pos.psq_score() + (pos.side_to_move() == WHITE ? Tempo : -Tempo);
384 // Probe the material hash table
385 ei.mi = pos.this_thread()->materialTable.probe(pos);
386 score += ei.mi->material_value();
388 // If we have a specialized evaluation function for the current material
389 // configuration, call it and return.
390 if (ei.mi->specialized_eval_exists())
393 return ei.mi->evaluate(pos);
396 // Probe the pawn hash table
397 ei.pi = pos.this_thread()->pawnTable.probe(pos);
398 score += ei.pi->pawns_value();
400 // Initialize attack and king safety bitboards
401 init_eval_info<WHITE>(pos, ei);
402 init_eval_info<BLACK>(pos, ei);
404 // Evaluate pieces and mobility
405 score += evaluate_pieces_of_color<WHITE, Trace>(pos, ei, mobilityWhite)
406 - evaluate_pieces_of_color<BLACK, Trace>(pos, ei, mobilityBlack);
408 score += apply_weight(mobilityWhite - mobilityBlack, Weights[Mobility]);
410 // Evaluate kings after all other pieces because we need complete attack
411 // information when computing the king safety evaluation.
412 score += evaluate_king<WHITE, Trace>(pos, ei, margins)
413 - evaluate_king<BLACK, Trace>(pos, ei, margins);
415 // Evaluate tactical threats, we need full attack information including king
416 score += evaluate_threats<WHITE>(pos, ei)
417 - evaluate_threats<BLACK>(pos, ei);
419 // Evaluate passed pawns, we need full attack information including king
420 score += evaluate_passed_pawns<WHITE>(pos, ei)
421 - evaluate_passed_pawns<BLACK>(pos, ei);
423 // If one side has only a king, check whether exists any unstoppable passed pawn
424 if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK))
425 score += evaluate_unstoppable_pawns(pos, ei);
427 // Evaluate space for both sides, only in middle-game.
428 if (ei.mi->space_weight())
430 int s = evaluate_space<WHITE>(pos, ei) - evaluate_space<BLACK>(pos, ei);
431 score += apply_weight(make_score(s * ei.mi->space_weight(), 0), Weights[Space]);
434 // Scale winning side if position is more drawish that what it appears
435 ScaleFactor sf = eg_value(score) > VALUE_DRAW ? ei.mi->scale_factor(pos, WHITE)
436 : ei.mi->scale_factor(pos, BLACK);
438 // If we don't already have an unusual scale factor, check for opposite
439 // colored bishop endgames, and use a lower scale for those.
440 if ( ei.mi->game_phase() < PHASE_MIDGAME
441 && pos.opposite_bishops()
442 && sf == SCALE_FACTOR_NORMAL)
444 // Only the two bishops ?
445 if ( pos.non_pawn_material(WHITE) == BishopValueMg
446 && pos.non_pawn_material(BLACK) == BishopValueMg)
448 // Check for KBP vs KB with only a single pawn that is almost
449 // certainly a draw or at least two pawns.
450 bool one_pawn = (pos.piece_count(WHITE, PAWN) + pos.piece_count(BLACK, PAWN) == 1);
451 sf = one_pawn ? ScaleFactor(8) : ScaleFactor(32);
454 // Endgame with opposite-colored bishops, but also other pieces. Still
455 // a bit drawish, but not as drawish as with only the two bishops.
456 sf = ScaleFactor(50);
459 margin = margins[pos.side_to_move()];
460 Value v = interpolate(score, ei.mi->game_phase(), sf);
462 // In case of tracing add all single evaluation contributions for both white and black
465 trace_add(PST, pos.psq_score());
466 trace_add(IMBALANCE, ei.mi->material_value());
467 trace_add(PAWN, ei.pi->pawns_value());
468 trace_add(MOBILITY, apply_weight(mobilityWhite, Weights[Mobility]), apply_weight(mobilityBlack, Weights[Mobility]));
469 trace_add(THREAT, evaluate_threats<WHITE>(pos, ei), evaluate_threats<BLACK>(pos, ei));
470 trace_add(PASSED, evaluate_passed_pawns<WHITE>(pos, ei), evaluate_passed_pawns<BLACK>(pos, ei));
471 trace_add(UNSTOPPABLE, evaluate_unstoppable_pawns(pos, ei));
472 Score w = make_score(ei.mi->space_weight() * evaluate_space<WHITE>(pos, ei), 0);
473 Score b = make_score(ei.mi->space_weight() * evaluate_space<BLACK>(pos, ei), 0);
474 trace_add(SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space]));
475 trace_add(TOTAL, score);
476 TraceStream << "\nUncertainty margin: White: " << to_cp(margins[WHITE])
477 << ", Black: " << to_cp(margins[BLACK])
478 << "\nScaling: " << std::noshowpos
479 << std::setw(6) << 100.0 * ei.mi->game_phase() / 128.0 << "% MG, "
480 << std::setw(6) << 100.0 * (1.0 - ei.mi->game_phase() / 128.0) << "% * "
481 << std::setw(6) << (100.0 * sf) / SCALE_FACTOR_NORMAL << "% EG.\n"
482 << "Total evaluation: " << to_cp(v);
485 return pos.side_to_move() == WHITE ? v : -v;
489 // init_eval_info() initializes king bitboards for given color adding
490 // pawn attacks. To be done at the beginning of the evaluation.
493 void init_eval_info(const Position& pos, EvalInfo& ei) {
495 const Color Them = (Us == WHITE ? BLACK : WHITE);
497 Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from<KING>(pos.king_square(Them));
498 ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us);
500 // Init king safety tables only if we are going to use them
501 if ( pos.piece_count(Us, QUEEN)
502 && pos.non_pawn_material(Us) >= QueenValueMg + RookValueMg)
504 ei.kingRing[Them] = (b | (Us == WHITE ? b >> 8 : b << 8));
505 b &= ei.attackedBy[Us][PAWN];
506 ei.kingAttackersCount[Us] = b ? popcount<Max15>(b) / 2 : 0;
507 ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0;
509 ei.kingRing[Them] = ei.kingAttackersCount[Us] = 0;
513 // evaluate_outposts() evaluates bishop and knight outposts squares
515 template<PieceType Piece, Color Us>
516 Score evaluate_outposts(const Position& pos, EvalInfo& ei, Square s) {
518 const Color Them = (Us == WHITE ? BLACK : WHITE);
520 assert (Piece == BISHOP || Piece == KNIGHT);
522 // Initial bonus based on square
523 Value bonus = OutpostBonus[Piece == BISHOP][relative_square(Us, s)];
525 // Increase bonus if supported by pawn, especially if the opponent has
526 // no minor piece which can exchange the outpost piece.
527 if (bonus && (ei.attackedBy[Us][PAWN] & s))
529 if ( !pos.pieces(Them, KNIGHT)
530 && !(same_color_squares(s) & pos.pieces(Them, BISHOP)))
531 bonus += bonus + bonus / 2;
535 return make_score(bonus, bonus);
539 // evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given color
541 template<PieceType Piece, Color Us, bool Trace>
542 Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score& mobility, Bitboard mobilityArea) {
548 Score score = SCORE_ZERO;
550 const Color Them = (Us == WHITE ? BLACK : WHITE);
551 const Square* pl = pos.piece_list(Us, Piece);
553 ei.attackedBy[Us][Piece] = 0;
555 while ((s = *pl++) != SQ_NONE)
557 // Find attacked squares, including x-ray attacks for bishops and rooks
558 if (Piece == KNIGHT || Piece == QUEEN)
559 b = pos.attacks_from<Piece>(s);
560 else if (Piece == BISHOP)
561 b = attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(Us, QUEEN));
562 else if (Piece == ROOK)
563 b = attacks_bb<ROOK>(s, pos.pieces() ^ pos.pieces(Us, ROOK, QUEEN));
567 ei.attackedBy[Us][Piece] |= b;
569 if (b & ei.kingRing[Them])
571 ei.kingAttackersCount[Us]++;
572 ei.kingAttackersWeight[Us] += KingAttackWeights[Piece];
573 Bitboard bb = (b & ei.attackedBy[Them][KING]);
575 ei.kingAdjacentZoneAttacksCount[Us] += popcount<Max15>(bb);
578 mob = (Piece != QUEEN ? popcount<Max15>(b & mobilityArea)
579 : popcount<Full >(b & mobilityArea));
581 mobility += MobilityBonus[Piece][mob];
583 // Add a bonus if a slider is pinning an enemy piece
584 if ( (Piece == BISHOP || Piece == ROOK || Piece == QUEEN)
585 && (PseudoAttacks[Piece][pos.king_square(Them)] & s))
587 b = BetweenBB[s][pos.king_square(Them)] & pos.pieces();
591 if (!more_than_one(b) && (b & pos.pieces(Them)))
592 score += ThreatBonus[Piece][type_of(pos.piece_on(lsb(b)))];
595 // Decrease score if we are attacked by an enemy pawn. Remaining part
596 // of threat evaluation must be done later when we have full attack info.
597 if (ei.attackedBy[Them][PAWN] & s)
598 score -= ThreatenedByPawnPenalty[Piece];
600 // Bishop and knight outposts squares
601 if ( (Piece == BISHOP || Piece == KNIGHT)
602 && !(pos.pieces(Them, PAWN) & attack_span_mask(Us, s)))
603 score += evaluate_outposts<Piece, Us>(pos, ei, s);
605 if ((Piece == ROOK || Piece == QUEEN) && relative_rank(Us, s) >= RANK_5)
607 // Major piece on 7th rank
608 if ( relative_rank(Us, s) == RANK_7
609 && relative_rank(Us, pos.king_square(Them)) == RANK_8)
610 score += (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus);
612 // Major piece attacking pawns on the same rank
613 Bitboard pawns = pos.pieces(Them, PAWN) & rank_bb(s);
615 score += (Piece == ROOK ? RookOnPawnBonus
616 : QueenOnPawnBonus) * popcount<Max15>(pawns);
619 // Special extra evaluation for bishops
620 if (Piece == BISHOP && pos.is_chess960())
622 // An important Chess960 pattern: A cornered bishop blocked by
623 // a friendly pawn diagonally in front of it is a very serious
624 // problem, especially when that pawn is also blocked.
625 if (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))
627 Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W);
628 if (pos.piece_on(s + d) == make_piece(Us, PAWN))
630 if (!pos.is_empty(s + d + pawn_push(Us)))
631 score -= 2*TrappedBishopA1H1Penalty;
632 else if (pos.piece_on(s + 2*d) == make_piece(Us, PAWN))
633 score -= TrappedBishopA1H1Penalty;
635 score -= TrappedBishopA1H1Penalty / 2;
640 // Special extra evaluation for rooks
643 // Open and half-open files
645 if (ei.pi->file_is_half_open(Us, f))
647 if (ei.pi->file_is_half_open(Them, f))
648 score += RookOpenFileBonus;
650 score += RookHalfOpenFileBonus;
653 // Penalize rooks which are trapped inside a king. Penalize more if
654 // king has lost right to castle.
655 if (mob > 6 || ei.pi->file_is_half_open(Us, f))
658 ksq = pos.king_square(Us);
660 if ( file_of(ksq) >= FILE_E
661 && file_of(s) > file_of(ksq)
662 && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(s)))
664 // Is there a half-open file between the king and the edge of the board?
665 if (!ei.pi->has_open_file_to_right(Us, file_of(ksq)))
666 score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
667 : (TrappedRookPenalty - mob * 16), 0);
669 else if ( file_of(ksq) <= FILE_D
670 && file_of(s) < file_of(ksq)
671 && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(s)))
673 // Is there a half-open file between the king and the edge of the board?
674 if (!ei.pi->has_open_file_to_left(Us, file_of(ksq)))
675 score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
676 : (TrappedRookPenalty - mob * 16), 0);
682 TracedScores[Us][Piece] = score;
688 // evaluate_threats<>() assigns bonuses according to the type of attacking piece
689 // and the type of attacked one.
692 Score evaluate_threats(const Position& pos, EvalInfo& ei) {
694 const Color Them = (Us == WHITE ? BLACK : WHITE);
696 Bitboard b, undefendedMinors, weakEnemies;
697 Score score = SCORE_ZERO;
699 // Undefended minors get penalized even if not under attack
700 undefendedMinors = pos.pieces(Them)
701 & (pos.pieces(BISHOP) | pos.pieces(KNIGHT))
702 & ~ei.attackedBy[Them][0];
704 if (undefendedMinors)
705 score += more_than_one(undefendedMinors) ? UndefendedMinorPenalty * 2
706 : UndefendedMinorPenalty;
708 // Enemy pieces not defended by a pawn and under our attack
709 weakEnemies = pos.pieces(Them)
710 & ~ei.attackedBy[Them][PAWN]
711 & ei.attackedBy[Us][0];
716 // Add bonus according to type of attacked enemy piece and to the
717 // type of attacking piece, from knights to queens. Kings are not
718 // considered because are already handled in king evaluation.
719 for (PieceType pt1 = KNIGHT; pt1 < KING; pt1++)
721 b = ei.attackedBy[Us][pt1] & weakEnemies;
723 for (PieceType pt2 = PAWN; pt2 < KING; pt2++)
724 if (b & pos.pieces(pt2))
725 score += ThreatBonus[pt1][pt2];
731 // evaluate_pieces_of_color<>() assigns bonuses and penalties to all the
732 // pieces of a given color.
734 template<Color Us, bool Trace>
735 Score evaluate_pieces_of_color(const Position& pos, EvalInfo& ei, Score& mobility) {
737 const Color Them = (Us == WHITE ? BLACK : WHITE);
739 Score score = mobility = SCORE_ZERO;
741 // Do not include in mobility squares protected by enemy pawns or occupied by our pieces
742 const Bitboard mobilityArea = ~(ei.attackedBy[Them][PAWN] | pos.pieces(Us));
744 score += evaluate_pieces<KNIGHT, Us, Trace>(pos, ei, mobility, mobilityArea);
745 score += evaluate_pieces<BISHOP, Us, Trace>(pos, ei, mobility, mobilityArea);
746 score += evaluate_pieces<ROOK, Us, Trace>(pos, ei, mobility, mobilityArea);
747 score += evaluate_pieces<QUEEN, Us, Trace>(pos, ei, mobility, mobilityArea);
749 // Sum up all attacked squares
750 ei.attackedBy[Us][0] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
751 | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
752 | ei.attackedBy[Us][QUEEN] | ei.attackedBy[Us][KING];
757 // evaluate_king<>() assigns bonuses and penalties to a king of a given color
759 template<Color Us, bool Trace>
760 Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]) {
762 const Color Them = (Us == WHITE ? BLACK : WHITE);
764 Bitboard undefended, b, b1, b2, safe;
766 const Square ksq = pos.king_square(Us);
768 // King shelter and enemy pawns storm
769 Score score = ei.pi->king_safety<Us>(pos, ksq);
771 // King safety. This is quite complicated, and is almost certainly far
772 // from optimally tuned.
773 if ( ei.kingAttackersCount[Them] >= 2
774 && ei.kingAdjacentZoneAttacksCount[Them])
776 // Find the attacked squares around the king which has no defenders
777 // apart from the king itself
778 undefended = ei.attackedBy[Them][0] & ei.attackedBy[Us][KING];
779 undefended &= ~( ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
780 | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
781 | ei.attackedBy[Us][QUEEN]);
783 // Initialize the 'attackUnits' variable, which is used later on as an
784 // index to the KingDangerTable[] array. The initial value is based on
785 // the number and types of the enemy's attacking pieces, the number of
786 // attacked and undefended squares around our king, the square of the
787 // king, and the quality of the pawn shelter.
788 attackUnits = std::min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
789 + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount<Max15>(undefended))
790 + InitKingDanger[relative_square(Us, ksq)]
791 - mg_value(score) / 32;
793 // Analyse enemy's safe queen contact checks. First find undefended
794 // squares around the king attacked by enemy queen...
795 b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them);
798 // ...then remove squares not supported by another enemy piece
799 b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT]
800 | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]);
802 attackUnits += QueenContactCheckBonus
804 * (Them == pos.side_to_move() ? 2 : 1);
807 // Analyse enemy's safe rook contact checks. First find undefended
808 // squares around the king attacked by enemy rooks...
809 b = undefended & ei.attackedBy[Them][ROOK] & ~pos.pieces(Them);
811 // Consider only squares where the enemy rook gives check
812 b &= PseudoAttacks[ROOK][ksq];
816 // ...then remove squares not supported by another enemy piece
817 b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT]
818 | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][QUEEN]);
820 attackUnits += RookContactCheckBonus
822 * (Them == pos.side_to_move() ? 2 : 1);
825 // Analyse enemy's safe distance checks for sliders and knights
826 safe = ~(pos.pieces(Them) | ei.attackedBy[Us][0]);
828 b1 = pos.attacks_from<ROOK>(ksq) & safe;
829 b2 = pos.attacks_from<BISHOP>(ksq) & safe;
831 // Enemy queen safe checks
832 b = (b1 | b2) & ei.attackedBy[Them][QUEEN];
834 attackUnits += QueenCheckBonus * popcount<Max15>(b);
836 // Enemy rooks safe checks
837 b = b1 & ei.attackedBy[Them][ROOK];
839 attackUnits += RookCheckBonus * popcount<Max15>(b);
841 // Enemy bishops safe checks
842 b = b2 & ei.attackedBy[Them][BISHOP];
844 attackUnits += BishopCheckBonus * popcount<Max15>(b);
846 // Enemy knights safe checks
847 b = pos.attacks_from<KNIGHT>(ksq) & ei.attackedBy[Them][KNIGHT] & safe;
849 attackUnits += KnightCheckBonus * popcount<Max15>(b);
851 // To index KingDangerTable[] attackUnits must be in [0, 99] range
852 attackUnits = std::min(99, std::max(0, attackUnits));
854 // Finally, extract the king danger score from the KingDangerTable[]
855 // array and subtract the score from evaluation. Set also margins[]
856 // value that will be used for pruning because this value can sometimes
857 // be very big, and so capturing a single attacking piece can therefore
858 // result in a score change far bigger than the value of the captured piece.
859 score -= KingDangerTable[Us == Eval::RootColor][attackUnits];
860 margins[Us] += mg_value(KingDangerTable[Us == Eval::RootColor][attackUnits]);
864 TracedScores[Us][KING] = score;
870 // evaluate_passed_pawns<>() evaluates the passed pawns of the given color
873 Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei) {
875 const Color Them = (Us == WHITE ? BLACK : WHITE);
877 Bitboard b, squaresToQueen, defendedSquares, unsafeSquares, supportingPawns;
878 Score score = SCORE_ZERO;
880 b = ei.pi->passed_pawns(Us);
886 Square s = pop_lsb(&b);
888 assert(pos.pawn_is_passed(Us, s));
890 int r = int(relative_rank(Us, s) - RANK_2);
891 int rr = r * (r - 1);
893 // Base bonus based on rank
894 Value mbonus = Value(20 * rr);
895 Value ebonus = Value(10 * (rr + r + 1));
899 Square blockSq = s + pawn_push(Us);
901 // Adjust bonus based on kings proximity
902 ebonus += Value(square_distance(pos.king_square(Them), blockSq) * 5 * rr);
903 ebonus -= Value(square_distance(pos.king_square(Us), blockSq) * 2 * rr);
905 // If blockSq is not the queening square then consider also a second push
906 if (rank_of(blockSq) != (Us == WHITE ? RANK_8 : RANK_1))
907 ebonus -= Value(square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * rr);
909 // If the pawn is free to advance, increase bonus
910 if (pos.is_empty(blockSq))
912 squaresToQueen = forward_bb(Us, s);
913 defendedSquares = squaresToQueen & ei.attackedBy[Us][0];
915 // If there is an enemy rook or queen attacking the pawn from behind,
916 // add all X-ray attacks by the rook or queen. Otherwise consider only
917 // the squares in the pawn's path attacked or occupied by the enemy.
918 if ( (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN))
919 && (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN) & pos.attacks_from<ROOK>(s)))
920 unsafeSquares = squaresToQueen;
922 unsafeSquares = squaresToQueen & (ei.attackedBy[Them][0] | pos.pieces(Them));
924 // If there aren't enemy attacks or pieces along the path to queen give
925 // huge bonus. Even bigger if we protect the pawn's path.
927 ebonus += Value(rr * (squaresToQueen == defendedSquares ? 17 : 15));
929 // OK, there are enemy attacks or pieces (but not pawns). Are those
930 // squares which are attacked by the enemy also attacked by us ?
931 // If yes, big bonus (but smaller than when there are no enemy attacks),
932 // if no, somewhat smaller bonus.
933 ebonus += Value(rr * ((unsafeSquares & defendedSquares) == unsafeSquares ? 13 : 8));
937 // Increase the bonus if the passed pawn is supported by a friendly pawn
938 // on the same rank and a bit smaller if it's on the previous rank.
939 supportingPawns = pos.pieces(Us, PAWN) & adjacent_files_bb(file_of(s));
940 if (supportingPawns & rank_bb(s))
941 ebonus += Value(r * 20);
943 else if (supportingPawns & rank_bb(s - pawn_push(Us)))
944 ebonus += Value(r * 12);
946 // Rook pawns are a special case: They are sometimes worse, and
947 // sometimes better than other passed pawns. It is difficult to find
948 // good rules for determining whether they are good or bad. For now,
949 // we try the following: Increase the value for rook pawns if the
950 // other side has no pieces apart from a knight, and decrease the
951 // value if the other side has a rook or queen.
952 if (file_of(s) == FILE_A || file_of(s) == FILE_H)
954 if (pos.non_pawn_material(Them) <= KnightValueMg)
955 ebonus += ebonus / 4;
956 else if (pos.pieces(Them, ROOK, QUEEN))
957 ebonus -= ebonus / 4;
959 score += make_score(mbonus, ebonus);
963 // Add the scores to the middle game and endgame eval
964 return apply_weight(score, Weights[PassedPawns]);
968 // evaluate_unstoppable_pawns() evaluates the unstoppable passed pawns for both sides, this is quite
969 // conservative and returns a winning score only when we are very sure that the pawn is winning.
971 Score evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei) {
973 Bitboard b, b2, blockers, supporters, queeningPath, candidates;
974 Square s, blockSq, queeningSquare;
975 Color c, winnerSide, loserSide;
976 bool pathDefended, opposed;
977 int pliesToGo, movesToGo, oppMovesToGo, sacptg, blockersCount, minKingDist, kingptg, d;
978 int pliesToQueen[] = { 256, 256 };
980 // Step 1. Hunt for unstoppable passed pawns. If we find at least one,
981 // record how many plies are required for promotion.
982 for (c = WHITE; c <= BLACK; c++)
984 // Skip if other side has non-pawn pieces
985 if (pos.non_pawn_material(~c))
988 b = ei.pi->passed_pawns(c);
993 queeningSquare = relative_square(c, file_of(s) | RANK_8);
994 queeningPath = forward_bb(c, s);
996 // Compute plies to queening and check direct advancement
997 movesToGo = rank_distance(s, queeningSquare) - int(relative_rank(c, s) == RANK_2);
998 oppMovesToGo = square_distance(pos.king_square(~c), queeningSquare) - int(c != pos.side_to_move());
999 pathDefended = ((ei.attackedBy[c][0] & queeningPath) == queeningPath);
1001 if (movesToGo >= oppMovesToGo && !pathDefended)
1004 // Opponent king cannot block because path is defended and position
1005 // is not in check. So only friendly pieces can be blockers.
1006 assert(!pos.in_check());
1007 assert((queeningPath & pos.pieces()) == (queeningPath & pos.pieces(c)));
1009 // Add moves needed to free the path from friendly pieces and retest condition
1010 movesToGo += popcount<Max15>(queeningPath & pos.pieces(c));
1012 if (movesToGo >= oppMovesToGo && !pathDefended)
1015 pliesToGo = 2 * movesToGo - int(c == pos.side_to_move());
1016 pliesToQueen[c] = std::min(pliesToQueen[c], pliesToGo);
1020 // Step 2. If either side cannot promote at least three plies before the other side then situation
1021 // becomes too complex and we give up. Otherwise we determine the possibly "winning side"
1022 if (abs(pliesToQueen[WHITE] - pliesToQueen[BLACK]) < 3)
1025 winnerSide = (pliesToQueen[WHITE] < pliesToQueen[BLACK] ? WHITE : BLACK);
1026 loserSide = ~winnerSide;
1028 // Step 3. Can the losing side possibly create a new passed pawn and thus prevent the loss?
1029 b = candidates = pos.pieces(loserSide, PAWN);
1035 // Compute plies from queening
1036 queeningSquare = relative_square(loserSide, file_of(s) | RANK_8);
1037 movesToGo = rank_distance(s, queeningSquare) - int(relative_rank(loserSide, s) == RANK_2);
1038 pliesToGo = 2 * movesToGo - int(loserSide == pos.side_to_move());
1040 // Check if (without even considering any obstacles) we're too far away or doubled
1041 if ( pliesToQueen[winnerSide] + 3 <= pliesToGo
1042 || (forward_bb(loserSide, s) & pos.pieces(loserSide, PAWN)))
1046 // If any candidate is already a passed pawn it _may_ promote in time. We give up.
1047 if (candidates & ei.pi->passed_pawns(loserSide))
1050 // Step 4. Check new passed pawn creation through king capturing and pawn sacrifices
1056 sacptg = blockersCount = 0;
1057 minKingDist = kingptg = 256;
1059 // Compute plies from queening
1060 queeningSquare = relative_square(loserSide, file_of(s) | RANK_8);
1061 movesToGo = rank_distance(s, queeningSquare) - int(relative_rank(loserSide, s) == RANK_2);
1062 pliesToGo = 2 * movesToGo - int(loserSide == pos.side_to_move());
1064 // Generate list of blocking pawns and supporters
1065 supporters = adjacent_files_bb(file_of(s)) & candidates;
1066 opposed = forward_bb(loserSide, s) & pos.pieces(winnerSide, PAWN);
1067 blockers = passed_pawn_mask(loserSide, s) & pos.pieces(winnerSide, PAWN);
1071 // How many plies does it take to remove all the blocking pawns?
1074 blockSq = pop_lsb(&blockers);
1077 // Check pawns that can give support to overcome obstacle, for instance
1078 // black pawns: a4, b4 white: b2 then pawn in b4 is giving support.
1081 b2 = supporters & in_front_bb(winnerSide, blockSq + pawn_push(winnerSide));
1083 while (b2) // This while-loop could be replaced with LSB/MSB (depending on color)
1085 d = square_distance(blockSq, pop_lsb(&b2)) - 2;
1086 movesToGo = std::min(movesToGo, d);
1090 // Check pawns that can be sacrificed against the blocking pawn
1091 b2 = attack_span_mask(winnerSide, blockSq) & candidates & ~(1ULL << s);
1093 while (b2) // This while-loop could be replaced with LSB/MSB (depending on color)
1095 d = square_distance(blockSq, pop_lsb(&b2)) - 2;
1096 movesToGo = std::min(movesToGo, d);
1099 // If obstacle can be destroyed with an immediate pawn exchange / sacrifice,
1100 // it's not a real obstacle and we have nothing to add to pliesToGo.
1104 // Plies needed to sacrifice against all the blocking pawns
1105 sacptg += movesToGo * 2;
1108 // Plies needed for the king to capture all the blocking pawns
1109 d = square_distance(pos.king_square(loserSide), blockSq);
1110 minKingDist = std::min(minKingDist, d);
1111 kingptg = (minKingDist + blockersCount) * 2;
1114 // Check if pawn sacrifice plan _may_ save the day
1115 if (pliesToQueen[winnerSide] + 3 > pliesToGo + sacptg)
1118 // Check if king capture plan _may_ save the day (contains some false positives)
1119 if (pliesToQueen[winnerSide] + 3 > pliesToGo + kingptg)
1123 // Winning pawn is unstoppable and will promote as first, return big score
1124 Score score = make_score(0, (Value) 1280 - 32 * pliesToQueen[winnerSide]);
1125 return winnerSide == WHITE ? score : -score;
1129 // evaluate_space() computes the space evaluation for a given side. The
1130 // space evaluation is a simple bonus based on the number of safe squares
1131 // available for minor pieces on the central four files on ranks 2--4. Safe
1132 // squares one, two or three squares behind a friendly pawn are counted
1133 // twice. Finally, the space bonus is scaled by a weight taken from the
1134 // material hash table. The aim is to improve play on game opening.
1136 int evaluate_space(const Position& pos, EvalInfo& ei) {
1138 const Color Them = (Us == WHITE ? BLACK : WHITE);
1140 // Find the safe squares for our pieces inside the area defined by
1141 // SpaceMask[]. A square is unsafe if it is attacked by an enemy
1142 // pawn, or if it is undefended and attacked by an enemy piece.
1143 Bitboard safe = SpaceMask[Us]
1144 & ~pos.pieces(Us, PAWN)
1145 & ~ei.attackedBy[Them][PAWN]
1146 & (ei.attackedBy[Us][0] | ~ei.attackedBy[Them][0]);
1148 // Find all squares which are at most three squares behind some friendly pawn
1149 Bitboard behind = pos.pieces(Us, PAWN);
1150 behind |= (Us == WHITE ? behind >> 8 : behind << 8);
1151 behind |= (Us == WHITE ? behind >> 16 : behind << 16);
1153 return popcount<Max15>(safe) + popcount<Max15>(behind & safe);
1157 // interpolate() interpolates between a middle game and an endgame score,
1158 // based on game phase. It also scales the return value by a ScaleFactor array.
1160 Value interpolate(const Score& v, Phase ph, ScaleFactor sf) {
1162 assert(mg_value(v) > -VALUE_INFINITE && mg_value(v) < VALUE_INFINITE);
1163 assert(eg_value(v) > -VALUE_INFINITE && eg_value(v) < VALUE_INFINITE);
1164 assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
1166 int ev = (eg_value(v) * int(sf)) / SCALE_FACTOR_NORMAL;
1167 int result = (mg_value(v) * int(ph) + ev * int(128 - ph)) / 128;
1168 return Value((result + GrainSize / 2) & ~(GrainSize - 1));
1172 // weight_option() computes the value of an evaluation weight, by combining
1173 // two UCI-configurable weights (midgame and endgame) with an internal weight.
1175 Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) {
1177 // Scale option value from 100 to 256
1178 int mg = Options[mgOpt] * 256 / 100;
1179 int eg = Options[egOpt] * 256 / 100;
1181 return apply_weight(make_score(mg, eg), internalWeight);
1185 // A couple of little helpers used by tracing code, to_cp() converts a value to
1186 // a double in centipawns scale, trace_add() stores white and black scores.
1188 double to_cp(Value v) { return double(v) / double(PawnValueMg); }
1190 void trace_add(int idx, Score wScore, Score bScore) {
1192 TracedScores[WHITE][idx] = wScore;
1193 TracedScores[BLACK][idx] = bScore;
1197 // trace_row() is an helper function used by tracing code to register the
1198 // values of a single evaluation term.
1200 void trace_row(const char* name, int idx) {
1202 Score wScore = TracedScores[WHITE][idx];
1203 Score bScore = TracedScores[BLACK][idx];
1206 case PST: case IMBALANCE: case PAWN: case UNSTOPPABLE: case TOTAL:
1207 TraceStream << std::setw(20) << name << " | --- --- | --- --- | "
1208 << std::setw(6) << to_cp(mg_value(wScore)) << " "
1209 << std::setw(6) << to_cp(eg_value(wScore)) << " \n";
1212 TraceStream << std::setw(20) << name << " | " << std::noshowpos
1213 << std::setw(5) << to_cp(mg_value(wScore)) << " "
1214 << std::setw(5) << to_cp(eg_value(wScore)) << " | "
1215 << std::setw(5) << to_cp(mg_value(bScore)) << " "
1216 << std::setw(5) << to_cp(eg_value(bScore)) << " | "
1218 << std::setw(6) << to_cp(mg_value(wScore - bScore)) << " "
1219 << std::setw(6) << to_cp(eg_value(wScore - bScore)) << " \n";