/*
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
struct EvalInfo {
// Pointers to material and pawn hash table entries
- MaterialEntry* mi;
- PawnEntry* 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
const int GrainSize = 8;
// Evaluation weights, initialized from UCI options
- enum { Mobility, PassedPawns, Space, KingDangerUs, KingDangerThem };
- Score Weights[6];
+ enum { Mobility, PassedPawns, Space };
+ Score Weights[3];
typedef Value V;
#define S(mg, eg) make_score(mg, eg)
//
// Values modified by Joona Kiiski
const Score WeightsInternal[] = {
- S(252, 344), S(216, 266), S(46, 0), S(247, 0), S(259, 0)
+ S(252, 344), S(216, 266), S(46, 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
+ const Score BishopPinBonus = make_score(66, 11);
+
// Bonus for having the side to move (modified by Joona Kiiski)
const Score Tempo = make_score(24, 11);
- // 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 and queens on the 7th rank
+ const Score RookOn7thBonus = make_score(3, 20);
+ const Score QueenOn7thBonus = make_score(1, 8);
+
+ // Rooks and queens attacking pawns on the same rank
+ const Score RookOnPawnBonus = make_score(3, 48);
+ const Score QueenOnPawnBonus = make_score(1, 40);
// Rooks on open files (modified by Joona Kiiski)
- const Score RookOpenFileBonus = make_score(43, 21);
+ const Score RookOpenFileBonus = make_score(43, 21);
const Score RookHalfOpenFileBonus = make_score(19, 10);
// Penalty for rooks trapped inside a friendly king which has lost the
// the strength of the enemy attack are added up into an integer, which
// is used as an index to KingDangerTable[].
//
+ // King safety evaluation is asymmetrical and different for us (root color)
+ // and for our opponent. These values are used to init KingDangerTable.
+ const int KingDangerWeights[] = { 259, 247 };
+
// KingAttackWeights[PieceType] contains king attack weights by piece type
const int KingAttackWeights[] = { 0, 0, 2, 2, 3, 5 };
// 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 {
namespace Eval {
- Color RootColor;
-
/// 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.
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]);
-
- // King safety is asymmetrical. Our king danger level is weighted by
- // "Cowardice" UCI parameter, instead the opponent one by "Aggressiveness".
- // 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.
+ 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]);
+
+ int KingDanger[] = { KingDangerWeights[0], KingDangerWeights[1] };
+
+ // If running in analysis mode, make sure we use symmetrical king safety.
+ // We do so by replacing both KingDanger weights by their average.
if (Options["UCI_AnalyseMode"])
- Weights[KingDangerUs] = Weights[KingDangerThem] = (Weights[KingDangerUs] + Weights[KingDangerThem]) / 2;
+ KingDanger[0] = KingDanger[1] = (KingDanger[0] + KingDanger[1]) / 2;
const int MaxSlope = 30;
const int Peak = 1280;
{
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]);
+ KingDangerTable[0][i] = apply_weight(make_score(t, 0), make_score(KingDanger[0], 0));
+ KingDangerTable[1][i] = apply_weight(make_score(t, 0), make_score(KingDanger[1], 0));
}
}
Value margin;
std::string totals;
- RootColor = pos.side_to_move();
+ Search::RootColor = pos.side_to_move();
TraceStream.str("");
TraceStream << std::showpoint << std::showpos << std::fixed << std::setprecision(2);
template<bool Trace>
Value do_evaluate(const Position& pos, Value& margin) {
- assert(!pos.in_check());
+ assert(!pos.checkers());
EvalInfo ei;
- Value margins[2];
+ Value margins[COLOR_NB];
Score score, mobilityWhite, mobilityBlack;
+ Thread* th = pos.this_thread();
// margins[] store the uncertainty estimation of position's evaluation
// that typically is used by the search for pruning decisions.
score = pos.psq_score() + (pos.side_to_move() == WHITE ? Tempo : -Tempo);
// Probe the material hash table
- ei.mi = pos.this_thread()->materialTable.probe(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 = pos.this_thread()->pawnTable.probe(pos);
+ ei.pi = Pawns::probe(pos, th->pawnsTable);
score += ei.pi->pawns_value();
// Initialize attack and king safety bitboards
&& 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.
// 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];
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.pieces();
-
- assert(b);
-
- if (!more_than_one(b) && (b & pos.pieces(Them)))
- score += ThreatBonus[Piece][type_of(pos.piece_on(lsb(b)))];
- }
-
// 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;
+
// Bishop and knight outposts squares
if ( (Piece == BISHOP || Piece == KNIGHT)
&& !(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)
+ if ((Piece == ROOK || Piece == QUEEN) && relative_rank(Us, s) >= RANK_5)
{
- score += (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus);
+ // Major piece on 7th rank
+ if ( relative_rank(Us, s) == RANK_7
+ && relative_rank(Us, pos.king_square(Them)) == RANK_8)
+ score += (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus);
+
+ // Major piece attacking pawns on the same rank
+ Bitboard pawns = pos.pieces(Them, PAWN) & rank_bb(s);
+ if (pawns)
+ score += (Piece == ROOK ? RookOnPawnBonus
+ : QueenOnPawnBonus) * popcount<Max15>(pawns);
}
// Special extra evaluation for bishops
// Undefended minors get penalized even if not under attack
undefendedMinors = pos.pieces(Them)
& (pos.pieces(BISHOP) | pos.pieces(KNIGHT))
- & ~ei.attackedBy[Them][0];
+ & ~ei.attackedBy[Them][ALL_PIECES];
if (undefendedMinors)
- score += more_than_one(undefendedMinors) ? UndefendedMinorPenalty * 2
- : UndefendedMinorPenalty;
+ score += UndefendedMinorPenalty;
// Enemy pieces not defended by a pawn and under our attack
weakEnemies = pos.pieces(Them)
& ~ei.attackedBy[Them][PAWN]
- & ei.attackedBy[Us][0];
+ & ei.attackedBy[Us][ALL_PIECES];
if (!weakEnemies)
return score;
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;
}
{
// 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]);
}
// 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 == Eval::RootColor][attackUnits];
- margins[Us] += mg_value(KingDangerTable[Us == Eval::RootColor][attackUnits]);
+ score -= KingDangerTable[Us == Search::RootColor][attackUnits];
+ margins[Us] += mg_value(KingDangerTable[Us == Search::RootColor][attackUnits]);
}
if (Trace)
if (pos.is_empty(blockSq))
{
squaresToQueen = forward_bb(Us, s);
- defendedSquares = squaresToQueen & ei.attackedBy[Us][0];
+ 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
&& (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.
// 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(Them, ROOK, QUEEN))
ebonus -= ebonus / 4;
// 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(!pos.checkers());
assert((queeningPath & pos.pieces()) == (queeningPath & pos.pieces(c)));
// Add moves needed to free the path from friendly pieces and retest condition
Bitboard safe = SpaceMask[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(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);
+
+ // Count safe + (behind & safe) with a single popcount
+ return popcount<Full>((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe));
}
// 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) {
projects / stockfish / blobdiff