/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include "thread.h"
#include "ucioption.h"
-Color EvalRootColor;
-
namespace {
// Struct EvalInfo contains various information computed and collected
struct EvalInfo {
// Pointers to material and pawn hash table entries
- MaterialInfo* mi;
- PawnInfo* pi;
+ Material::Entry* mi;
+ Pawns::Entry* pi;
// attackedBy[color][piece type] is a bitboard representing all squares
- // attacked by a given color and piece type, attackedBy[color][0] contains
- // all squares attacked by the given color.
- Bitboard attackedBy[2][8];
+ // attacked by a given color and piece type, attackedBy[color][ALL_PIECES]
+ // contains all squares attacked by the given color.
+ Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB];
// kingRing[color] is the zone around the king which is considered
// by the king safety evaluation. This consists of the squares directly
// squares two ranks in front of the king. For instance, if black's king
// is on g8, kingRing[BLACK] is a bitboard containing the squares f8, h8,
// f7, g7, h7, f6, g6 and h6.
- Bitboard kingRing[2];
+ Bitboard kingRing[COLOR_NB];
// kingAttackersCount[color] is the number of pieces of the given color
// which attack a square in the kingRing of the enemy king.
- int kingAttackersCount[2];
+ int kingAttackersCount[COLOR_NB];
// 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
- int kingAttackersWeight[2];
+ int kingAttackersWeight[COLOR_NB];
// kingAdjacentZoneAttacksCount[color] is the number of attacks to squares
// directly adjacent to the king of the given color. Pieces which attack
// more than one square are counted multiple times. For instance, if black's
// king is on g8 and there's a white knight on g5, this knight adds
// 2 to kingAdjacentZoneAttacksCount[BLACK].
- int kingAdjacentZoneAttacksCount[2];
+ int kingAdjacentZoneAttacksCount[COLOR_NB];
};
// Evaluation grain size, must be a power of 2
//
// Values modified by Joona Kiiski
const Score WeightsInternal[] = {
- S(252, 344), S(216, 266), S(46, 0), S(247, 0), S(259, 0)
+ S(289, 344), S(221, 273), S(46, 0), S(271, 0), S(307, 0)
};
// MobilityBonus[PieceType][attacked] contains mobility bonuses for middle and
// OutpostBonus[PieceType][Square] contains outpost bonuses of knights and
// bishops, indexed by piece type and square (from white's point of view).
- const Value OutpostBonus[][64] = {
+ const Value OutpostBonus[][SQUARE_NB] = {
{
// A B C D E F G H
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Knights
// ThreatBonus[attacking][attacked] contains threat bonuses according to
// which piece type attacks which one.
- const Score ThreatBonus[][8] = {
+ const Score ThreatBonus[][PIECE_TYPE_NB] = {
{}, {},
{ S(0, 0), S( 7, 39), S( 0, 0), S(24, 49), S(41,100), S(41,100) }, // KNIGHT
{ S(0, 0), S( 7, 39), S(24, 49), S( 0, 0), S(41,100), S(41,100) }, // BISHOP
- { S(0, 0), S(-1, 29), S(15, 49), S(15, 49), S( 0, 0), S(24, 49) }, // ROOK
+ { S(0, 0), S( 0, 22), S(15, 49), S(15, 49), S( 0, 0), S(24, 49) }, // ROOK
{ S(0, 0), S(15, 39), S(15, 39), S(15, 39), S(15, 39), S( 0, 0) } // QUEEN
};
#undef S
- // 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);
-
- // Rooks on open files (modified by Joona Kiiski)
- const Score RookOpenFileBonus = make_score(43, 21);
- const Score RookHalfOpenFileBonus = make_score(19, 10);
+ const Score Tempo = make_score(24, 11);
- // Penalty for rooks trapped inside a friendly king which has lost the
- // right to castle.
- const Value TrappedRookPenalty = Value(180);
+ const Score BishopPinBonus = make_score(66, 11);
+ const Score RookOn7thBonus = make_score(11, 20);
+ const Score QueenOn7thBonus = make_score( 3, 8);
+ const Score RookOnPawnBonus = make_score(10, 28);
+ const Score QueenOnPawnBonus = make_score( 4, 20);
+ const Score RookOpenFileBonus = make_score(43, 21);
+ const Score RookHalfOpenFileBonus = make_score(19, 10);
+ const Score BishopPawnsPenalty = make_score(8, 12);
+ const Score UndefendedMinorPenalty = make_score(25, 10);
+ const Score TrappedRookPenalty = make_score(90, 0);
// 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
// happen in Chess960 games.
- const Score TrappedBishopA1H1Penalty = make_score(100, 100);
+ const Score TrappedBishopA1H1Penalty = make_score(50, 50);
// The SpaceMask[Color] contains the area of the board which is considered
// by the space evaluation. In the middle game, each side is given a bonus
// KingDangerTable[Color][attackUnits] contains the actual king danger
// weighted scores, indexed by color and by a calculated integer number.
- Score KingDangerTable[2][128];
+ Score KingDangerTable[COLOR_NB][128];
// TracedTerms[Color][PieceType || TracedType] contains a breakdown of the
// evaluation terms, used when tracing.
- Score TracedScores[2][16];
+ Score TracedScores[COLOR_NB][16];
std::stringstream TraceStream;
enum TracedType {
- PST = 8, IMBALANCE = 9, MOBILITY = 10, THREAT = 11,
- PASSED = 12, UNSTOPPABLE = 13, SPACE = 14, TOTAL = 15
+ PST = 8, IMBALANCE = 9, MOBILITY = 10, THREAT = 11,
+ PASSED = 12, UNSTOPPABLE = 13, SPACE = 14, TOTAL = 15
};
// Function prototypes
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);
+ void trace_row(const char* name, int idx);
}
-/// evaluate() is the main evaluation function. It always computes two
-/// values, an endgame score and a middle game score, and interpolates
-/// between them based on the remaining material.
-Value evaluate(const Position& pos, Value& margin) { return do_evaluate<false>(pos, margin); }
+namespace Eval {
+
+ /// evaluate() is the main evaluation function. It always computes two
+ /// values, an endgame score and a middle game score, and interpolates
+ /// between them based on the remaining material.
+
+ Value evaluate(const Position& pos, Value& margin) {
+ return do_evaluate<false>(pos, margin);
+ }
+
+
+ /// init() computes evaluation weights from the corresponding UCI parameters
+ /// and setup king tables.
+
+ void init() {
+
+ Weights[Mobility] = weight_option("Mobility (Middle Game)", "Mobility (Endgame)", WeightsInternal[Mobility]);
+ Weights[PassedPawns] = weight_option("Passed Pawns (Middle Game)", "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));
+
+ KingDangerTable[1][i] = apply_weight(make_score(t, 0), Weights[KingDangerUs]);
+ KingDangerTable[0][i] = apply_weight(make_score(t, 0), Weights[KingDangerThem]);
+ }
+ }
+
+
+ /// trace() is like evaluate() but instead of a value returns a string suitable
+ /// to be print on stdout with the detailed descriptions and values of each
+ /// evaluation term. Used mainly for debugging.
+
+ std::string trace(const Position& pos) {
+
+ Value margin;
+ std::string totals;
+
+ Search::RootColor = pos.side_to_move();
+
+ TraceStream.str("");
+ TraceStream << std::showpoint << std::showpos << std::fixed << std::setprecision(2);
+ memset(TracedScores, 0, 2 * 16 * sizeof(Score));
+
+ do_evaluate<true>(pos, margin);
+
+ totals = TraceStream.str();
+ TraceStream.str("");
+
+ TraceStream << std::setw(21) << "Eval term " << "| White | Black | Total \n"
+ << " | MG EG | MG EG | MG EG \n"
+ << "---------------------+-------------+-------------+---------------\n";
+
+ trace_row("Material, PST, Tempo", PST);
+ trace_row("Material imbalance", IMBALANCE);
+ trace_row("Pawns", PAWN);
+ trace_row("Knights", KNIGHT);
+ trace_row("Bishops", BISHOP);
+ trace_row("Rooks", ROOK);
+ trace_row("Queens", QUEEN);
+ trace_row("Mobility", MOBILITY);
+ trace_row("King safety", KING);
+ trace_row("Threats", THREAT);
+ trace_row("Passed pawns", PASSED);
+ trace_row("Unstoppable pawns", UNSTOPPABLE);
+ trace_row("Space", SPACE);
+
+ TraceStream << "---------------------+-------------+-------------+---------------\n";
+ trace_row("Total", TOTAL);
+ TraceStream << totals;
+
+ return TraceStream.str();
+ }
+
+} // namespace Eval
+
namespace {
template<bool Trace>
Value do_evaluate(const Position& pos, Value& margin) {
+ assert(!pos.checkers());
+
EvalInfo ei;
- Value margins[2];
+ Value margins[COLOR_NB];
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();
+ Thread* th = pos.this_thread();
// 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 = Material::probe(pos, th->materialTable, th->endgames);
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 = Pawns::probe(pos, th->pawnsTable);
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 ?
- if ( pos.non_pawn_material(WHITE) == BishopValueMidgame
- && pos.non_pawn_material(BLACK) == BishopValueMidgame)
+ 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.
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]));
return pos.side_to_move() == WHITE ? v : -v;
}
-} // namespace
-
-
-/// eval_init() reads evaluation weights from the corresponding UCI parameters
-/// and setup weights and tables.
-void eval_init() {
-
- const Value MaxSlope = Value(30);
- const Value Peak = Value(1280);
- Value t[100];
-
- // King safety is asymmetrical. Our king danger level is weighted by
- // "Cowardice" UCI parameter, instead the opponent one by "Aggressiveness".
- Weights[Mobility] = weight_option("Mobility (Middle Game)", "Mobility (Endgame)", WeightsInternal[Mobility]);
- Weights[PassedPawns] = weight_option("Passed Pawns (Middle Game)", "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]);
-
- // If running in analysis mode, make sure we use symmetrical king safety. We do this
- // by replacing both Weights[kingDangerUs] and Weights[kingDangerThem] by their average.
- if (Options["UCI_AnalyseMode"])
- Weights[KingDangerUs] = Weights[KingDangerThem] = (Weights[KingDangerUs] + Weights[KingDangerThem]) / 2;
-
- // First setup the base table
- for (int i = 0; i < 100; i++)
- {
- t[i] = Value(int(0.4 * i * i));
-
- if (i > 0)
- t[i] = std::min(t[i], t[i - 1] + MaxSlope);
-
- t[i] = std::min(t[i], Peak);
- }
-
- // Then apply the weights and get the final KingDangerTable[] array
- for (Color c = WHITE; c <= BLACK; c++)
- for (int i = 0; i < 100; i++)
- KingDangerTable[c == WHITE][i] = apply_weight(make_score(t[i], 0), Weights[KingDangerUs + c]);
-}
-
-
-namespace {
// init_eval_info() initializes king bitboards for given color adding
// pawn attacks. To be done at the beginning of the evaluation.
// Init king safety tables only if we are going to use them
if ( pos.piece_count(Us, QUEEN)
- && pos.non_pawn_material(Us) >= QueenValueMidgame + RookValueMidgame)
+ && pos.non_pawn_material(Us) > QueenValueMg + PawnValueMg)
{
ei.kingRing[Them] = (b | (Us == WHITE ? b >> 8 : b << 8));
b &= ei.attackedBy[Us][PAWN];
// no minor piece which can exchange the outpost piece.
if (bonus && (ei.attackedBy[Us][PAWN] & s))
{
- if ( !pos.pieces(KNIGHT, Them)
- && !(same_color_squares(s) & pos.pieces(BISHOP, Them)))
+ if ( !pos.pieces(Them, KNIGHT)
+ && !(same_color_squares(s) & pos.pieces(Them, BISHOP)))
bonus += bonus + bonus / 2;
else
bonus += bonus / 2;
Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score& mobility, Bitboard mobilityArea) {
Bitboard b;
- Square s, ksq;
- int mob;
- File f;
+ Square s;
Score score = SCORE_ZERO;
const Color Them = (Us == WHITE ? BLACK : WHITE);
while ((s = *pl++) != SQ_NONE)
{
// Find attacked squares, including x-ray attacks for bishops and rooks
- if (Piece == KNIGHT || Piece == QUEEN)
- b = pos.attacks_from<Piece>(s);
- else if (Piece == BISHOP)
- b = attacks_bb<BISHOP>(s, pos.occupied_squares() & ~pos.pieces(QUEEN, Us));
- else if (Piece == ROOK)
- b = attacks_bb<ROOK>(s, pos.occupied_squares() & ~pos.pieces(ROOK, QUEEN, Us));
- else
- assert(false);
+ b = Piece == BISHOP ? attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(Us, QUEEN))
+ : Piece == ROOK ? attacks_bb< ROOK>(s, pos.pieces() ^ pos.pieces(Us, ROOK, QUEEN))
+ : pos.attacks_from<Piece>(s);
ei.attackedBy[Us][Piece] |= b;
ei.kingAdjacentZoneAttacksCount[Us] += popcount<Max15>(bb);
}
- mob = (Piece != QUEEN ? popcount<Max15>(b & mobilityArea)
- : popcount<Full >(b & mobilityArea));
-
+ int mob = popcount<Piece == QUEEN ? Full : Max15>(b & mobilityArea);
mobility += MobilityBonus[Piece][mob];
- // Add a bonus if a slider is pinning an enemy piece
- if ( (Piece == BISHOP || Piece == ROOK || Piece == QUEEN)
- && (PseudoAttacks[Piece][pos.king_square(Them)] & s))
- {
- b = BetweenBB[s][pos.king_square(Them)] & pos.occupied_squares();
-
- assert(b);
-
- if (single_bit(b) && (b & pos.pieces(Them)))
- score += ThreatBonus[Piece][type_of(pos.piece_on(first_1(b)))] / 2;
- }
-
// Decrease score if we are attacked by an enemy pawn. Remaining part
// of threat evaluation must be done later when we have full attack info.
if (ei.attackedBy[Them][PAWN] & s)
score -= ThreatenedByPawnPenalty[Piece];
+ // Otherwise give a bonus if we are a bishop and can pin a piece or can
+ // give a discovered check through an x-ray attack.
+ else if ( Piece == BISHOP
+ && (PseudoAttacks[Piece][pos.king_square(Them)] & s)
+ && !more_than_one(BetweenBB[s][pos.king_square(Them)] & pos.pieces()))
+ score += BishopPinBonus;
+
+ // Penalty for bishop with same coloured pawns
+ if (Piece == BISHOP)
+ score -= BishopPawnsPenalty * ei.pi->pawns_on_same_color_squares(Us, s);
+
// Bishop and knight outposts squares
if ( (Piece == BISHOP || Piece == KNIGHT)
- && !(pos.pieces(PAWN, Them) & attack_span_mask(Us, s)))
+ && !(pos.pieces(Them, PAWN) & attack_span_mask(Us, s)))
score += evaluate_outposts<Piece, Us>(pos, ei, s);
- // Queen or rook on 7th rank
if ( (Piece == ROOK || Piece == QUEEN)
- && relative_rank(Us, s) == RANK_7
- && relative_rank(Us, pos.king_square(Them)) == RANK_8)
- {
- score += (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus);
- }
-
- // Special extra evaluation for bishops
- if (Piece == BISHOP && pos.is_chess960())
+ && relative_rank(Us, s) >= RANK_5)
{
- // 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 (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))
- {
- if (!pos.square_is_empty(s + d + pawn_push(Us)))
- score -= 2*TrappedBishopA1H1Penalty;
- else if (pos.piece_on(s + 2*d) == make_piece(Us, PAWN))
- score -= TrappedBishopA1H1Penalty;
- else
- score -= TrappedBishopA1H1Penalty / 2;
- }
- }
+ // Major piece on 7th rank and enemy king trapped on 8th
+ if ( relative_rank(Us, s) == RANK_7
+ && relative_rank(Us, pos.king_square(Them)) == RANK_8)
+ score += Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus;
+
+ // Major piece attacking enemy pawns on the same rank
+ Bitboard pawns = pos.pieces(Them, PAWN) & rank_bb(s);
+ if (pawns)
+ score += popcount<Max15>(pawns) * (Piece == ROOK ? RookOnPawnBonus : QueenOnPawnBonus);
}
// Special extra evaluation for rooks
if (Piece == ROOK)
{
- // Open and half-open files
- f = file_of(s);
- if (ei.pi->file_is_half_open(Us, f))
- {
- if (ei.pi->file_is_half_open(Them, f))
- score += RookOpenFileBonus;
- else
- score += RookHalfOpenFileBonus;
- }
+ // Give a bonus for a rook on a open or half-open file
+ if (ei.pi->half_open(Us, file_of(s)))
+ score += ei.pi->half_open(Them, file_of(s)) ? RookOpenFileBonus
+ : RookHalfOpenFileBonus;
+ if (mob > 6 || ei.pi->half_open(Us, file_of(s)))
+ continue;
+
+ Square ksq = pos.king_square(Us);
// Penalize rooks which are trapped inside a king. Penalize more if
// king has lost right to castle.
- if (mob > 6 || ei.pi->file_is_half_open(Us, f))
- continue;
-
- ksq = pos.king_square(Us);
+ 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->half_open_on_side(Us, file_of(ksq), file_of(ksq) < FILE_E))
+ score -= (TrappedRookPenalty - make_score(mob * 8, 0)) * (pos.can_castle(Us) ? 1 : 2);
+ }
- if ( file_of(ksq) >= FILE_E
- && file_of(s) > file_of(ksq)
- && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_right(Us, file_of(ksq)))
- score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
- : (TrappedRookPenalty - mob * 16), 0);
- }
- else if ( file_of(ksq) <= FILE_D
- && file_of(s) < file_of(ksq)
- && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_left(Us, file_of(ksq)))
- score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
- : (TrappedRookPenalty - mob * 16), 0);
- }
+ // 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 ( Piece == BISHOP
+ && pos.is_chess960()
+ && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1)))
+ {
+ const enum Piece P = make_piece(Us, PAWN);
+ Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W);
+ if (pos.piece_on(s + d) == P)
+ score -= !pos.is_empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1Penalty * 4
+ : pos.piece_on(s + d + d) == P ? TrappedBishopA1H1Penalty * 2
+ : 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
+ undefendedMinors = pos.pieces(Them, BISHOP, KNIGHT)
+ & ~ei.attackedBy[Them][ALL_PIECES];
+
+ if (undefendedMinors)
+ score += UndefendedMinorPenalty;
+
// Enemy pieces not defended by a pawn and under our attack
- Bitboard weakEnemies = pos.pieces(Them)
- & ~ei.attackedBy[Them][PAWN]
- & ei.attackedBy[Us][0];
+ weakEnemies = pos.pieces(Them)
+ & ~ei.attackedBy[Them][PAWN]
+ & ei.attackedBy[Us][ALL_PIECES];
+
if (!weakEnemies)
- return SCORE_ZERO;
+ return score;
// Add bonus according to type of attacked enemy piece and to the
// type of attacking piece, from knights to queens. Kings are not
Score score = mobility = SCORE_ZERO;
// Do not include in mobility squares protected by enemy pawns or occupied by our pieces
- const Bitboard mobilityArea = ~(ei.attackedBy[Them][PAWN] | pos.pieces(Us));
+ const Bitboard mobilityArea = ~(ei.attackedBy[Them][PAWN] | pos.pieces(Us, PAWN, KING));
score += evaluate_pieces<KNIGHT, Us, Trace>(pos, ei, mobility, mobilityArea);
score += evaluate_pieces<BISHOP, Us, Trace>(pos, ei, mobility, mobilityArea);
score += evaluate_pieces<QUEEN, Us, Trace>(pos, ei, mobility, mobilityArea);
// Sum up all attacked squares
- ei.attackedBy[Us][0] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
- | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
- | ei.attackedBy[Us][QUEEN] | ei.attackedBy[Us][KING];
+ ei.attackedBy[Us][ALL_PIECES] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
+ | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
+ | ei.attackedBy[Us][QUEEN] | ei.attackedBy[Us][KING];
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.
{
// Find the attacked squares around the king which has no defenders
// apart from the king itself
- undefended = ei.attackedBy[Them][0] & ei.attackedBy[Us][KING];
+ undefended = ei.attackedBy[Them][ALL_PIECES] & ei.attackedBy[Us][KING];
undefended &= ~( ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
| ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
| ei.attackedBy[Us][QUEEN]);
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(score) / 32;
// Analyse enemy's safe queen contact checks. First find undefended
// squares around the king attacked by enemy queen...
}
// Analyse enemy's safe distance checks for sliders and knights
- safe = ~(pos.pieces(Them) | ei.attackedBy[Us][0]);
+ safe = ~(pos.pieces(Them) | ei.attackedBy[Us][ALL_PIECES]);
b1 = pos.attacks_from<ROOK>(ksq) & safe;
b2 = pos.attacks_from<BISHOP>(ksq) & safe;
// value that will be used for pruning because this value can sometimes
// be very big, and so capturing a single attacking piece can therefore
// result in a score change far bigger than the value of the captured piece.
- score -= KingDangerTable[Us == EvalRootColor][attackUnits];
- margins[Us] += mg_value(KingDangerTable[Us == EvalRootColor][attackUnits]);
+ score -= KingDangerTable[Us == Search::RootColor][attackUnits];
+ margins[Us] += mg_value(KingDangerTable[Us == Search::RootColor][attackUnits]);
}
if (Trace)
return SCORE_ZERO;
do {
- Square s = pop_1st_bit(&b);
+ Square s = pop_lsb(&b);
assert(pos.pawn_is_passed(Us, s));
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.is_empty(blockSq))
{
- squaresToQueen = squares_in_front_of(Us, s);
- defendedSquares = squaresToQueen & ei.attackedBy[Us][0];
+ squaresToQueen = forward_bb(Us, s);
+ defendedSquares = squaresToQueen & ei.attackedBy[Us][ALL_PIECES];
// If there is an enemy rook or queen attacking the pawn from behind,
// add all X-ray attacks by the rook or queen. Otherwise consider only
// the squares in the pawn's path attacked or occupied by the enemy.
- if ( (squares_in_front_of(Them, s) & pos.pieces(ROOK, QUEEN, Them))
- && (squares_in_front_of(Them, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from<ROOK>(s)))
+ if ( (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN))
+ && (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN) & pos.attacks_from<ROOK>(s)))
unsafeSquares = squaresToQueen;
else
- unsafeSquares = squaresToQueen & (ei.attackedBy[Them][0] | pos.pieces(Them));
+ unsafeSquares = squaresToQueen & (ei.attackedBy[Them][ALL_PIECES] | pos.pieces(Them));
- // If there aren't enemy attacks or pieces along the path to queen give
- // huge bonus. Even bigger if we protect the pawn's path.
- if (!unsafeSquares)
- ebonus += Value(rr * (squaresToQueen == defendedSquares ? 17 : 15));
- else
- // OK, there are enemy attacks or pieces (but not pawns). Are those
- // squares which are attacked by the enemy also attacked by us ?
- // If yes, big bonus (but smaller than when there are no enemy attacks),
- // if no, somewhat smaller bonus.
- ebonus += Value(rr * ((unsafeSquares & defendedSquares) == unsafeSquares ? 13 : 8));
+ // If there aren't enemy attacks huge bonus, a bit smaller if at
+ // least block square is not attacked, otherwise smallest bonus.
+ int k = !unsafeSquares ? 15 : !(unsafeSquares & blockSq) ? 9 : 3;
+
+ // Big bonus if the path to queen is fully defended, a bit less
+ // if at least block square is defended.
+ if (defendedSquares == squaresToQueen)
+ k += 6;
+
+ else if (defendedSquares & blockSq)
+ k += (unsafeSquares & defendedSquares) == unsafeSquares ? 4 : 2;
+
+ mbonus += Value(k * rr), ebonus += Value(k * rr);
}
} // rr != 0
// Increase the bonus if the passed pawn is supported by a friendly pawn
// on the same rank and a bit smaller if it's on the previous rank.
- supportingPawns = pos.pieces(PAWN, Us) & adjacent_files_bb(file_of(s));
+ supportingPawns = pos.pieces(Us, PAWN) & adjacent_files_bb(file_of(s));
if (supportingPawns & rank_bb(s))
ebonus += Value(r * 20);
// value if the other side has a rook or queen.
if (file_of(s) == FILE_A || file_of(s) == FILE_H)
{
- if (pos.non_pawn_material(Them) <= KnightValueMidgame)
+ if (pos.non_pawn_material(Them) <= KnightValueMg)
ebonus += ebonus / 4;
- else if (pos.pieces(ROOK, QUEEN, Them))
+ else if (pos.pieces(Them, ROOK, QUEEN))
ebonus -= ebonus / 4;
}
score += make_score(mbonus, ebonus);
while (b)
{
- s = pop_1st_bit(&b);
- queeningSquare = relative_square(c, make_square(file_of(s), RANK_8));
- queeningPath = squares_in_front_of(c, s);
+ s = pop_lsb(&b);
+ queeningSquare = relative_square(c, file_of(s) | RANK_8);
+ queeningPath = forward_bb(c, s);
// Compute plies to queening and check direct advancement
movesToGo = rank_distance(s, queeningSquare) - int(relative_rank(c, s) == RANK_2);
oppMovesToGo = square_distance(pos.king_square(~c), queeningSquare) - int(c != pos.side_to_move());
- pathDefended = ((ei.attackedBy[c][0] & queeningPath) == queeningPath);
+ pathDefended = ((ei.attackedBy[c][ALL_PIECES] & queeningPath) == queeningPath);
if (movesToGo >= oppMovesToGo && !pathDefended)
continue;
// Opponent king cannot block because path is defended and position
// is not in check. So only friendly pieces can be blockers.
- assert(!pos.in_check());
- assert((queeningPath & pos.occupied_squares()) == (queeningPath & pos.pieces(c)));
+ assert(!pos.checkers());
+ assert((queeningPath & pos.pieces()) == (queeningPath & pos.pieces(c)));
// Add moves needed to free the path from friendly pieces and retest condition
movesToGo += popcount<Max15>(queeningPath & pos.pieces(c));
loserSide = ~winnerSide;
// Step 3. Can the losing side possibly create a new passed pawn and thus prevent the loss?
- b = candidates = pos.pieces(PAWN, loserSide);
+ b = candidates = pos.pieces(loserSide, PAWN);
while (b)
{
- s = pop_1st_bit(&b);
+ s = pop_lsb(&b);
// Compute plies from queening
- queeningSquare = relative_square(loserSide, make_square(file_of(s), RANK_8));
+ queeningSquare = relative_square(loserSide, file_of(s) | RANK_8);
movesToGo = rank_distance(s, queeningSquare) - int(relative_rank(loserSide, s) == RANK_2);
pliesToGo = 2 * movesToGo - int(loserSide == pos.side_to_move());
// Check if (without even considering any obstacles) we're too far away or doubled
if ( pliesToQueen[winnerSide] + 3 <= pliesToGo
- || (squares_in_front_of(loserSide, s) & pos.pieces(PAWN, loserSide)))
+ || (forward_bb(loserSide, s) & pos.pieces(loserSide, PAWN)))
candidates ^= s;
}
while (b)
{
- s = pop_1st_bit(&b);
+ s = pop_lsb(&b);
sacptg = blockersCount = 0;
minKingDist = kingptg = 256;
// Compute plies from queening
- queeningSquare = relative_square(loserSide, make_square(file_of(s), RANK_8));
+ queeningSquare = relative_square(loserSide, file_of(s) | RANK_8);
movesToGo = rank_distance(s, queeningSquare) - int(relative_rank(loserSide, s) == RANK_2);
pliesToGo = 2 * movesToGo - int(loserSide == pos.side_to_move());
// Generate list of blocking pawns and supporters
supporters = adjacent_files_bb(file_of(s)) & candidates;
- opposed = squares_in_front_of(loserSide, s) & pos.pieces(PAWN, winnerSide);
- blockers = passed_pawn_mask(loserSide, s) & pos.pieces(PAWN, winnerSide);
+ opposed = forward_bb(loserSide, s) & pos.pieces(winnerSide, PAWN);
+ blockers = passed_pawn_mask(loserSide, s) & pos.pieces(winnerSide, PAWN);
assert(blockers);
// How many plies does it take to remove all the blocking pawns?
while (blockers)
{
- blockSq = pop_1st_bit(&blockers);
+ blockSq = pop_lsb(&blockers);
movesToGo = 256;
// Check pawns that can give support to overcome obstacle, for instance
while (b2) // This while-loop could be replaced with LSB/MSB (depending on color)
{
- d = square_distance(blockSq, pop_1st_bit(&b2)) - 2;
+ d = square_distance(blockSq, pop_lsb(&b2)) - 2;
movesToGo = std::min(movesToGo, d);
}
}
while (b2) // This while-loop could be replaced with LSB/MSB (depending on color)
{
- d = square_distance(blockSq, pop_1st_bit(&b2)) - 2;
+ d = square_distance(blockSq, pop_lsb(&b2)) - 2;
movesToGo = std::min(movesToGo, d);
}
}
// Winning pawn is unstoppable and will promote as first, return big score
- Score score = make_score(0, (Value) 0x500 - 0x20 * pliesToQueen[winnerSide]);
+ Score score = make_score(0, (Value) 1280 - 32 * pliesToQueen[winnerSide]);
return winnerSide == WHITE ? score : -score;
}
// SpaceMask[]. A square is unsafe if it is attacked by an enemy
// pawn, or if it is undefended and attacked by an enemy piece.
Bitboard safe = SpaceMask[Us]
- & ~pos.pieces(PAWN, Us)
+ & ~pos.pieces(Us, PAWN)
& ~ei.attackedBy[Them][PAWN]
- & (ei.attackedBy[Us][0] | ~ei.attackedBy[Them][0]);
+ & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]);
// Find all squares which are at most three squares behind some friendly pawn
- Bitboard behind = pos.pieces(PAWN, Us);
+ Bitboard behind = pos.pieces(Us, PAWN);
behind |= (Us == WHITE ? behind >> 8 : behind << 8);
behind |= (Us == WHITE ? behind >> 16 : behind << 16);
- return popcount<Max15>(safe) + popcount<Max15>(behind & safe);
- }
-
+ // Since SpaceMask[Us] is fully on our half of the board
+ assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 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);
+ // Count safe + (behind & safe) with a single popcount
+ return popcount<Full>((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe));
}
- // 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);
// A couple of little helpers used by tracing code, to_cp() converts a value to
// a double in centipawns scale, trace_add() stores white and black scores.
- double to_cp(Value v) { return double(v) / double(PawnValueMidgame); }
+ double to_cp(Value v) { return double(v) / double(PawnValueMg); }
void trace_add(int idx, Score wScore, Score bScore) {
- TracedScores[WHITE][idx] = wScore;
- TracedScores[BLACK][idx] = bScore;
+ TracedScores[WHITE][idx] = wScore;
+ TracedScores[BLACK][idx] = bScore;
}
+
// trace_row() is an helper function used by tracing code to register the
// values of a single evaluation term.
- void trace_row(const char *name, int idx) {
+ void trace_row(const char* name, int idx) {
Score wScore = TracedScores[WHITE][idx];
Score bScore = TracedScores[BLACK][idx];
}
}
}
-
-
-/// trace_evaluate() is like evaluate() but instead of a value returns a string
-/// suitable to be print on stdout with the detailed descriptions and values of
-/// each evaluation term. Used mainly for debugging.
-
-std::string trace_evaluate(const Position& pos) {
-
- Value margin;
- std::string totals;
-
- TraceStream.str("");
- TraceStream << std::showpoint << std::showpos << std::fixed << std::setprecision(2);
- memset(TracedScores, 0, 2 * 16 * sizeof(Score));
-
- do_evaluate<true>(pos, margin);
-
- totals = TraceStream.str();
- TraceStream.str("");
-
- TraceStream << std::setw(21) << "Eval term " << "| White | Black | Total \n"
- << " | MG EG | MG EG | MG EG \n"
- << "---------------------+-------------+-------------+---------------\n";
-
- trace_row("Material, PST, Tempo", PST);
- trace_row("Material imbalance", IMBALANCE);
- trace_row("Pawns", PAWN);
- trace_row("Knights", KNIGHT);
- trace_row("Bishops", BISHOP);
- trace_row("Rooks", ROOK);
- trace_row("Queens", QUEEN);
- trace_row("Mobility", MOBILITY);
- trace_row("King safety", KING);
- trace_row("Threats", THREAT);
- trace_row("Passed pawns", PASSED);
- trace_row("Unstoppable pawns", UNSTOPPABLE);
- trace_row("Space", SPACE);
-
- TraceStream << "---------------------+-------------+-------------+---------------\n";
- trace_row("Total", TOTAL);
- TraceStream << totals;
-
- return TraceStream.str();
-}
projects / stockfish / blobdiff