////
#include <cassert>
+#include <iostream>
+#include <iomanip>
+#include <sstream>
#include "bitcount.h"
#include "evaluate.h"
V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0),
V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0),
V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0),
- V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0),
- V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0),
- V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) },
+ V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0) },
{
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Bishops
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0),
V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0),
V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0),
V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0),
- V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0),
- V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0),
- V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }
+ V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0) }
};
// ThreatBonus[attacking][attacked] contains threat bonuses according to
// right to castle.
const Value TrappedRookPenalty = Value(180);
+ // 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);
+
// 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
// based on how many squares inside this area are safe and available for
const int KingAttackWeights[] = { 0, 0, 2, 2, 3, 5 };
// Bonuses for enemy's safe checks
- const int QueenContactCheckBonus = 3;
- const int QueenCheckBonus = 2;
- const int RookCheckBonus = 1;
+ const int QueenContactCheckBonus = 6;
+ const int RookContactCheckBonus = 4;
+ const int QueenCheckBonus = 3;
+ const int RookCheckBonus = 2;
const int BishopCheckBonus = 1;
const int KnightCheckBonus = 1;
// weighted scores, indexed by color and by a calculated integer number.
Score KingDangerTable[2][128];
+ // TracedTerms[Color][PieceType || TracedType] contains a breakdown of the
+ // evaluation terms, used when tracing.
+ Score TracedTerms[2][16];
+ std::stringstream TraceStream;
+
+ enum TracedType {
+ PST = 8, IMBALANCE = 9, MOBILITY = 10, THREAT = 11,
+ PASSED = 12, UNSTOPPABLE = 13, SPACE = 14, TOTAL = 15
+ };
+
// Pawn and material hash tables, indexed by the current thread id.
- // Note that they will be initialized at 0 being global variables.
+ // We use per-thread tables so that once we get a pointer to an entry
+ // its life time is unlimited and we don't have to care about someone
+ // changing the entry under our feet.
MaterialInfoTable* MaterialTable[MAX_THREADS];
PawnInfoTable* PawnTable[MAX_THREADS];
// Function prototypes
- template<bool HasPopCnt>
- Value do_evaluate(const Position& pos, Value margins[]);
+ template<bool HasPopCnt, bool Trace>
+ Value do_evaluate(const Position& pos, Value& margin);
template<Color Us, bool HasPopCnt>
void init_eval_info(const Position& pos, EvalInfo& ei);
- template<Color Us, bool HasPopCnt>
+ template<Color Us, bool HasPopCnt, bool Trace>
Score evaluate_pieces_of_color(const Position& pos, EvalInfo& ei, Score& mobility);
- template<Color Us, bool HasPopCnt>
+ template<Color Us, bool HasPopCnt, bool Trace>
Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]);
template<Color Us>
template<Color Us>
Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei);
- Score apply_weight(Score v, Score weight);
- Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]);
+ template<bool HasPopCnt>
+ 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);
Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight);
void init_safety();
}
-////
-//// Functions
-////
-
+/// prefetchTables() is called in do_move() to prefetch pawn and material
+/// hash tables data that will be needed shortly after in evaluation.
-/// Prefetches in pawn hash tables
+void prefetchTables(Key pKey, Key mKey, int threadID) {
-void prefetchPawn(Key key, int threadID) {
-
- PawnTable[threadID]->prefetch(key);
+ PawnTable[threadID]->prefetch(pKey);
+ MaterialTable[threadID]->prefetch(mKey);
}
/// 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 margins[]) {
+Value evaluate(const Position& pos, Value& margin) {
- return CpuHasPOPCNT ? do_evaluate<true>(pos, margins)
- : do_evaluate<false>(pos, margins);
+ return CpuHasPOPCNT ? do_evaluate<true, false>(pos, margin)
+ : do_evaluate<false, false>(pos, margin);
}
namespace {
-template<bool HasPopCnt>
-Value do_evaluate(const Position& pos, Value margins[]) {
+double to_cp(Value v) { return double(v) / double(PawnValueMidgame); }
+
+void trace_add(int idx, Score term_w, Score term_b = Score(0)) {
+
+ TracedTerms[WHITE][idx] = term_w;
+ TracedTerms[BLACK][idx] = term_b;
+}
+
+template<bool HasPopCnt, bool Trace>
+Value do_evaluate(const Position& pos, Value& margin) {
EvalInfo ei;
- ScaleFactor factor[2];
+ Value margins[2];
Score mobilityWhite, mobilityBlack;
assert(pos.is_ok());
// in the position object (material + piece square tables).
Score bonus = pos.value();
- // margins[color] is the uncertainty estimation of position's evaluation
- // and typically is used by the search for pruning decisions.
+ // 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;
// Probe the material hash table
// If we have a specialized evaluation function for the current material
// configuration, call it and return.
if (mi->specialized_eval_exists())
+ {
+ margin = VALUE_ZERO;
return mi->evaluate(pos);
-
- // After get_material_info() call that modifies them
- factor[WHITE] = mi->scale_factor(pos, WHITE);
- factor[BLACK] = mi->scale_factor(pos, BLACK);
+ }
// Probe the pawn hash table
ei.pi = PawnTable[pos.thread()]->get_pawn_info(pos);
init_eval_info<BLACK, HasPopCnt>(pos, ei);
// Evaluate pieces and mobility
- bonus += evaluate_pieces_of_color<WHITE, HasPopCnt>(pos, ei, mobilityWhite)
- - evaluate_pieces_of_color<BLACK, HasPopCnt>(pos, ei, mobilityBlack);
+ bonus += evaluate_pieces_of_color<WHITE, HasPopCnt, Trace>(pos, ei, mobilityWhite)
+ - evaluate_pieces_of_color<BLACK, HasPopCnt, Trace>(pos, ei, mobilityBlack);
bonus += apply_weight(mobilityWhite - mobilityBlack, Weights[Mobility]);
// Evaluate kings after all other pieces because we need complete attack
// information when computing the king safety evaluation.
- bonus += evaluate_king<WHITE, HasPopCnt>(pos, ei, margins)
- - evaluate_king<BLACK, HasPopCnt>(pos, ei, margins);
+ bonus += evaluate_king<WHITE, HasPopCnt, Trace>(pos, ei, margins)
+ - evaluate_king<BLACK, HasPopCnt, Trace>(pos, ei, margins);
// Evaluate tactical threats, we need full attack information including king
bonus += evaluate_threats<WHITE>(pos, ei)
bonus += evaluate_passed_pawns<WHITE>(pos, ei)
- evaluate_passed_pawns<BLACK>(pos, ei);
- Phase phase = mi->game_phase();
-
- // Middle-game specific evaluation terms
- if (phase > PHASE_ENDGAME)
+ // If one side has only a king, check whether exists any unstoppable passed pawn
+ if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK))
{
- // Evaluate pawn storms in positions with opposite castling
- if ( square_file(pos.king_square(WHITE)) >= FILE_E
- && square_file(pos.king_square(BLACK)) <= FILE_D)
-
- bonus += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0);
+ bonus += evaluate_unstoppable_pawns<HasPopCnt>(pos, ei);
- else if ( square_file(pos.king_square(WHITE)) <= FILE_D
- && square_file(pos.king_square(BLACK)) >= FILE_E)
+ if (Trace)
+ trace_add(UNSTOPPABLE, evaluate_unstoppable_pawns<HasPopCnt>(pos, ei));
+ }
- bonus += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0);
+ // Evaluate space for both sides, only in middle-game.
+ if (mi->space_weight())
+ {
+ int s_w = evaluate_space<WHITE, HasPopCnt>(pos, ei);
+ int s_b = evaluate_space<BLACK, HasPopCnt>(pos, ei);
+ bonus += apply_weight(make_score((s_w - s_b) * mi->space_weight(), 0), Weights[Space]);
- // Evaluate space for both sides
- if (mi->space_weight() > 0)
- {
- int s = evaluate_space<WHITE, HasPopCnt>(pos, ei) - evaluate_space<BLACK, HasPopCnt>(pos, ei);
- bonus += apply_weight(make_score(s * mi->space_weight(), 0), Weights[Space]);
- }
+ if (Trace)
+ trace_add(SPACE, apply_weight(make_score(s_w * mi->space_weight(), make_score(0, 0)), Weights[Space]),
+ apply_weight(make_score(s_b * mi->space_weight(), make_score(0, 0)), Weights[Space]));
}
+ // Scale winning side if position is more drawish that what it appears
+ ScaleFactor sf = eg_value(bonus) > VALUE_DRAW ? mi->scale_factor(pos, WHITE)
+ : mi->scale_factor(pos, BLACK);
+ Phase phase = mi->game_phase();
+
// If we don't already have an unusual scale factor, check for opposite
- // colored bishop endgames, and use a lower scale for those
+ // colored bishop endgames, and use a lower scale for those.
if ( phase < PHASE_MIDGAME
&& pos.opposite_colored_bishops()
- && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && eg_value(bonus) > VALUE_ZERO)
- || (factor[BLACK] == SCALE_FACTOR_NORMAL && eg_value(bonus) < VALUE_ZERO)))
+ && sf == SCALE_FACTOR_NORMAL)
{
- ScaleFactor sf;
-
// Only the two bishops ?
if ( pos.non_pawn_material(WHITE) == BishopValueMidgame
&& pos.non_pawn_material(BLACK) == BishopValueMidgame)
// Endgame with opposite-colored bishops, but also other pieces. Still
// a bit drawish, but not as drawish as with only the two bishops.
sf = ScaleFactor(50);
-
- if (factor[WHITE] == SCALE_FACTOR_NORMAL)
- factor[WHITE] = sf;
- if (factor[BLACK] == SCALE_FACTOR_NORMAL)
- factor[BLACK] = sf;
}
// Interpolate between the middle game and the endgame score
- Value v = scale_by_game_phase(bonus, phase, factor);
+ margin = margins[pos.side_to_move()];
+ Value v = scale_by_game_phase(bonus, phase, sf);
+
+ if (Trace)
+ {
+ trace_add(PST, pos.value());
+ trace_add(IMBALANCE, mi->material_value());
+ trace_add(PAWN, apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]));
+ trace_add(MOBILITY, apply_weight(mobilityWhite, Weights[Mobility]), apply_weight(mobilityBlack, Weights[Mobility]));
+ trace_add(THREAT, evaluate_threats<WHITE>(pos, ei), evaluate_threats<BLACK>(pos, ei));
+ trace_add(PASSED, evaluate_passed_pawns<WHITE>(pos, ei), evaluate_passed_pawns<BLACK>(pos, ei));
+ trace_add(TOTAL, bonus);
+ TraceStream << "\nUncertainty margin: White: " << to_cp(margins[WHITE])
+ << ", Black: " << to_cp(margins[BLACK])
+ << "\nScaling: " << std::noshowpos
+ << std::setw(6) << 100.0 * phase/128.0 << "% MG, "
+ << std::setw(6) << 100.0 * (1.0 - phase/128.0) << "% * "
+ << std::setw(6) << (100.0 * sf) / SCALE_FACTOR_NORMAL << "% EG.\n"
+ << "Total evaluation: " << to_cp(v);
+ }
+
return pos.side_to_move() == WHITE ? v : -v;
}
/// read_weights() reads evaluation weights from the corresponding UCI parameters
-void read_weights(Color us) {
+void read_evaluation_uci_options(Color us) {
// 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.
- if (get_option_value_bool("UCI_AnalyseMode"))
+ if (Options["UCI_AnalyseMode"].value<bool>())
Weights[kingDangerUs] = Weights[kingDangerThem] = (Weights[kingDangerUs] + Weights[kingDangerThem]) / 2;
init_safety();
template<Color Us, bool HasPopCnt>
void init_eval_info(const Position& pos, EvalInfo& ei) {
+ const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15;
const Color Them = (Us == WHITE ? BLACK : WHITE);
Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from<KING>(pos.king_square(Them));
- ei.kingZone[Us] = (b | (Us == WHITE ? b >> 8 : b << 8));
ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us);
- b &= ei.attackedBy[Us][PAWN];
- ei.kingAttackersCount[Us] = b ? count_1s_max_15<HasPopCnt>(b) / 2 : EmptyBoardBB;
- ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = EmptyBoardBB;
+
+ // 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)
+ {
+ ei.kingZone[Us] = (b | (Us == WHITE ? b >> 8 : b << 8));
+ b &= ei.attackedBy[Us][PAWN];
+ ei.kingAttackersCount[Us] = b ? count_1s<Max15>(b) / 2 : 0;
+ ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0;
+ } else
+ ei.kingZone[Us] = ei.kingAttackersCount[Us] = 0;
}
// evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given color
- template<PieceType Piece, Color Us, bool HasPopCnt>
- Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score& mobility, Bitboard no_mob_area) {
+ template<PieceType Piece, Color Us, bool HasPopCnt, bool Trace>
+ Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score& mobility, Bitboard mobilityArea) {
Bitboard b;
Square s, ksq;
File f;
Score bonus = SCORE_ZERO;
+ const BitCountType Full = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64 : CNT32;
+ const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15;
const Color Them = (Us == WHITE ? BLACK : WHITE);
const Square* ptr = pos.piece_list_begin(Us, Piece);
ei.kingAttackersWeight[Us] += KingAttackWeights[Piece];
Bitboard bb = (b & ei.attackedBy[Them][KING]);
if (bb)
- ei.kingAdjacentZoneAttacksCount[Us] += count_1s_max_15<HasPopCnt>(bb);
+ ei.kingAdjacentZoneAttacksCount[Us] += count_1s<Max15>(bb);
}
// Mobility
- mob = (Piece != QUEEN ? count_1s_max_15<HasPopCnt>(b & no_mob_area)
- : count_1s<HasPopCnt>(b & no_mob_area));
+ mob = (Piece != QUEEN ? count_1s<Max15>(b & mobilityArea)
+ : count_1s<Full >(b & mobilityArea));
mobility += MobilityBonus[Piece][mob];
bonus += (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus);
}
+ // Special extra evaluation for bishops
+ if (Piece == BISHOP && pos.is_chess960())
+ {
+ // 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) + (square_file(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)))
+ bonus -= 2*TrappedBishopA1H1Penalty;
+ else if (pos.piece_on(s + 2*d) == make_piece(Us, PAWN))
+ bonus -= TrappedBishopA1H1Penalty;
+ else
+ bonus -= TrappedBishopA1H1Penalty / 2;
+ }
+ }
+ }
+
// Special extra evaluation for rooks
if (Piece == ROOK)
{
}
}
}
+
+ if (Trace)
+ TracedTerms[Us][Piece] = bonus;
+
return bonus;
}
// evaluate_pieces_of_color<>() assigns bonuses and penalties to all the
// pieces of a given color.
- template<Color Us, bool HasPopCnt>
+ template<Color Us, bool HasPopCnt, bool Trace>
Score evaluate_pieces_of_color(const Position& pos, EvalInfo& ei, Score& mobility) {
const Color Them = (Us == WHITE ? BLACK : WHITE);
Score bonus = mobility = SCORE_ZERO;
// Do not include in mobility squares protected by enemy pawns or occupied by our pieces
- const Bitboard no_mob_area = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us));
+ const Bitboard mobilityArea = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us));
- bonus += evaluate_pieces<KNIGHT, Us, HasPopCnt>(pos, ei, mobility, no_mob_area);
- bonus += evaluate_pieces<BISHOP, Us, HasPopCnt>(pos, ei, mobility, no_mob_area);
- bonus += evaluate_pieces<ROOK, Us, HasPopCnt>(pos, ei, mobility, no_mob_area);
- bonus += evaluate_pieces<QUEEN, Us, HasPopCnt>(pos, ei, mobility, no_mob_area);
+ bonus += evaluate_pieces<KNIGHT, Us, HasPopCnt, Trace>(pos, ei, mobility, mobilityArea);
+ bonus += evaluate_pieces<BISHOP, Us, HasPopCnt, Trace>(pos, ei, mobility, mobilityArea);
+ bonus += evaluate_pieces<ROOK, Us, HasPopCnt, Trace>(pos, ei, mobility, mobilityArea);
+ bonus += evaluate_pieces<QUEEN, Us, HasPopCnt, Trace>(pos, ei, mobility, mobilityArea);
// Sum up all attacked squares
ei.attackedBy[Us][0] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
// evaluate_king<>() assigns bonuses and penalties to a king of a given color
- template<Color Us, bool HasPopCnt>
+ template<Color Us, bool HasPopCnt, bool Trace>
Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]) {
+ const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15;
const Color Them = (Us == WHITE ? BLACK : WHITE);
Bitboard undefended, b, b1, b2, safe;
// King safety. This is quite complicated, and is almost certainly far
// from optimally tuned.
- if ( ei.kingAttackersCount[Them] >= 2
- && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame
- && pos.piece_count(Them, QUEEN) >= 1
+ if ( ei.kingAttackersCount[Them] >= 2
&& ei.kingAdjacentZoneAttacksCount[Them])
{
// Find the attacked squares around the king which has no defenders
// attacked and undefended squares around our king, the square of the
// king, and the quality of the pawn shelter.
attackUnits = Min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
- + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s_max_15<HasPopCnt>(undefended))
+ + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s<Max15>(undefended))
+ InitKingDanger[relative_square(Us, ksq)]
- mg_value(ei.pi->king_shelter<Us>(pos, ksq)) / 32;
| ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]);
if (b)
attackUnits += QueenContactCheckBonus
- * count_1s_max_15<HasPopCnt>(b)
+ * count_1s<Max15>(b)
+ * (Them == pos.side_to_move() ? 2 : 1);
+ }
+
+ // Analyse enemy's safe rook contact checks. First find undefended
+ // squares around the king attacked by enemy rooks...
+ b = undefended & ei.attackedBy[Them][ROOK] & ~pos.pieces_of_color(Them);
+
+ // Consider only squares where the enemy rook gives check
+ b &= RookPseudoAttacks[ksq];
+
+ if (b)
+ {
+ // ...then remove squares not supported by another enemy piece
+ b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT]
+ | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][QUEEN]);
+ if (b)
+ attackUnits += RookContactCheckBonus
+ * count_1s<Max15>(b)
* (Them == pos.side_to_move() ? 2 : 1);
}
// Enemy queen safe checks
b = (b1 | b2) & ei.attackedBy[Them][QUEEN];
if (b)
- attackUnits += QueenCheckBonus * count_1s_max_15<HasPopCnt>(b);
+ attackUnits += QueenCheckBonus * count_1s<Max15>(b);
// Enemy rooks safe checks
b = b1 & ei.attackedBy[Them][ROOK];
if (b)
- attackUnits += RookCheckBonus * count_1s_max_15<HasPopCnt>(b);
+ attackUnits += RookCheckBonus * count_1s<Max15>(b);
// Enemy bishops safe checks
b = b2 & ei.attackedBy[Them][BISHOP];
if (b)
- attackUnits += BishopCheckBonus * count_1s_max_15<HasPopCnt>(b);
+ attackUnits += BishopCheckBonus * count_1s<Max15>(b);
// Enemy knights safe checks
b = pos.attacks_from<KNIGHT>(ksq) & ei.attackedBy[Them][KNIGHT] & safe;
if (b)
- attackUnits += KnightCheckBonus * count_1s_max_15<HasPopCnt>(b);
+ attackUnits += KnightCheckBonus * count_1s<Max15>(b);
// To index KingDangerTable[] attackUnits must be in [0, 99] range
attackUnits = Min(99, Max(0, attackUnits));
bonus -= KingDangerTable[Us][attackUnits];
margins[Us] += mg_value(KingDangerTable[Us][attackUnits]);
}
+
+ if (Trace)
+ TracedTerms[Us][KING] = bonus;
+
return bonus;
}
// 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_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them))
- && (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from<ROOK>(s)))
+ 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)))
unsafeSquares = squaresToQueen;
else
unsafeSquares = squaresToQueen & (ei.attackedBy[Them][0] | pos.pieces_of_color(Them));
return apply_weight(bonus, Weights[PassedPawns]);
}
+ // evaluate_unstoppable_pawns() evaluates the unstoppable passed pawns for both sides
+ template<bool HasPopCnt>
+ Score evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei) {
+
+ const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15;
+
+ // Step 1. Hunt for unstoppable pawns. If we find at least one, record how many plies
+ // are required for promotion
+ int pliesToGo[2] = {256, 256};
+
+ for (Color c = WHITE; c <= BLACK; c++)
+ {
+ // Skip if other side has non-pawn pieces
+ if (pos.non_pawn_material(opposite_color(c)))
+ continue;
+
+ Bitboard b = ei.pi->passed_pawns(c);
+
+ while (b)
+ {
+ Square s = pop_1st_bit(&b);
+ Square queeningSquare = relative_square(c, make_square(square_file(s), RANK_8));
+
+ int mtg = RANK_8 - relative_rank(c, s) - int(relative_rank(c, s) == RANK_2);
+ int oppmtg = square_distance(pos.king_square(opposite_color(c)), queeningSquare) - int(c != pos.side_to_move());
+ bool pathDefended = ((ei.attackedBy[c][0] & squares_in_front_of(c, s)) == squares_in_front_of(c, s));
+
+ if (mtg >= oppmtg && !pathDefended)
+ continue;
+
+ int blockerCount = count_1s<Max15>(squares_in_front_of(c, s) & pos.occupied_squares());
+ mtg += blockerCount;
+
+ if (mtg >= oppmtg && !pathDefended)
+ continue;
+
+ int ptg = 2 * mtg - int(c == pos.side_to_move());
+
+ if (ptg < pliesToGo[c])
+ pliesToGo[c] = ptg;
+ }
+ }
+
+ // Step 2. If either side cannot promote at least three plies before the other side then
+ // situation becomes too complex and we give up. Otherwise we determine the possibly "winning side"
+ if (abs(pliesToGo[WHITE] - pliesToGo[BLACK]) < 3)
+ return make_score(0, 0);
+
+ Color winnerSide = (pliesToGo[WHITE] < pliesToGo[BLACK] ? WHITE : BLACK);
+ Color loserSide = opposite_color(winnerSide);
+
+ // Step 3. Can the losing side possibly create a new passed pawn and thus prevent the loss?
+ // We collect the potential candidates in potentialBB.
+ Bitboard pawnBB = pos.pieces(PAWN, loserSide);
+ Bitboard potentialBB = pawnBB;
+ const Bitboard passedBB = ei.pi->passed_pawns(loserSide);
+
+ while(pawnBB)
+ {
+ Square psq = pop_1st_bit(&pawnBB);
+
+ // Check direct advancement
+ int mtg = RANK_8 - relative_rank(loserSide, psq) - int(relative_rank(loserSide, psq) == RANK_2);
+ int ptg = 2 * mtg - int(loserSide == pos.side_to_move());
+
+ // Check if (without even considering any obstacles) we're too far away
+ if (pliesToGo[winnerSide] + 3 <= ptg)
+ {
+ clear_bit(&potentialBB, psq);
+ continue;
+ }
+
+ // If this is passed pawn, then it _may_ promote in time. We give up.
+ if (bit_is_set(passedBB, psq))
+ return make_score(0, 0);
+
+ // Doubled pawn is worthless
+ if (squares_in_front_of(loserSide, psq) & (pos.pieces(PAWN, loserSide)))
+ {
+ clear_bit(&potentialBB, psq);
+ continue;
+ }
+ }
+
+ // Step 4. Check new passed pawn creation through king capturing and sacrifises
+ pawnBB = potentialBB;
+
+ while(pawnBB)
+ {
+ Square psq = pop_1st_bit(&pawnBB);
+
+ int mtg = RANK_8 - relative_rank(loserSide, psq) - int(relative_rank(loserSide, psq) == RANK_2);
+ int ptg = 2 * mtg - int(loserSide == pos.side_to_move());
+
+ // Generate list of obstacles
+ Bitboard obsBB = passed_pawn_mask(loserSide, psq) & pos.pieces(PAWN, winnerSide);
+ const bool pawnIsOpposed = squares_in_front_of(loserSide, psq) & obsBB;
+ assert(obsBB);
+
+ // How many plies does it take to remove all the obstacles?
+ int sacptg = 0;
+ int realObsCount = 0;
+ int minKingDist = 256;
+
+ while(obsBB)
+ {
+ Square obSq = pop_1st_bit(&obsBB);
+ int minMoves = 256;
+
+ // Check pawns that can give support to overcome obstacle (Eg. wp: a4,b4 bp: b2. b4 is giving support)
+ if (!pawnIsOpposed && square_file(psq) != square_file(obSq))
+ {
+ Bitboard supBB = in_front_bb(winnerSide, Square(obSq + (winnerSide == WHITE ? 8 : -8)))
+ & neighboring_files_bb(psq) & potentialBB;
+
+ while(supBB) // This while-loop could be replaced with supSq = LSB/MSB(supBB) (depending on color)
+ {
+ Square supSq = pop_1st_bit(&supBB);
+ int dist = square_distance(obSq, supSq);
+ minMoves = Min(minMoves, dist - 2);
+ }
+
+ }
+
+ // Check pawns that can be sacrifised
+ Bitboard sacBB = passed_pawn_mask(winnerSide, obSq) & neighboring_files_bb(obSq) & potentialBB & ~(1ULL << psq);
+
+ while(sacBB) // This while-loop could be replaced with sacSq = LSB/MSB(sacBB) (depending on color)
+ {
+ Square sacSq = pop_1st_bit(&sacBB);
+ int dist = square_distance(obSq, sacSq);
+ minMoves = Min(minMoves, dist - 2);
+ }
+
+ // If obstacle can be destroyed with immediate pawn sacrifise, it's not real obstacle
+ if (minMoves <= 0)
+ continue;
+
+ // Pawn sac calculations
+ sacptg += minMoves * 2;
+
+ // King capture calc
+ realObsCount++;
+ int kingDist = square_distance(pos.king_square(loserSide), obSq);
+ minKingDist = Min(minKingDist, kingDist);
+ }
+
+ // Check if pawn sac plan _may_ save the day
+ if (pliesToGo[winnerSide] + 3 > ptg + sacptg)
+ return make_score(0, 0);
+
+ // Check if king capture plan _may_ save the day (contains some false positives)
+ int kingptg = (minKingDist + realObsCount) * 2;
+ if (pliesToGo[winnerSide] + 3 > ptg + kingptg)
+ return make_score(0, 0);
+ }
+
+ // Step 5. Assign bonus
+ const int Sign[2] = {1, -1};
+ return Sign[winnerSide] * make_score(0, (Value) 0x500 - 0x20 * pliesToGo[winnerSide]);
+ }
+
// evaluate_space() computes the space evaluation for a given side. The
// space evaluation is a simple bonus based on the number of safe squares
template<Color Us, bool HasPopCnt>
int evaluate_space(const Position& pos, EvalInfo& ei) {
+ const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15;
const Color Them = (Us == WHITE ? BLACK : WHITE);
// Find the safe squares for our pieces inside the area defined by
behind |= (Us == WHITE ? behind >> 8 : behind << 8);
behind |= (Us == WHITE ? behind >> 16 : behind << 16);
- return count_1s_max_15<HasPopCnt>(safe) + count_1s_max_15<HasPopCnt>(behind & safe);
+ return count_1s<Max15>(safe) + count_1s<Max15>(behind & safe);
}
// scale_by_game_phase() 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, const ScaleFactor sf[]) {
+ Value scale_by_game_phase(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);
assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
- Value eg = eg_value(v);
- ScaleFactor f = sf[eg > VALUE_ZERO ? WHITE : BLACK];
- Value ev = Value((eg * int(f)) / SCALE_FACTOR_NORMAL);
-
+ int ev = (eg_value(v) * int(sf)) / SCALE_FACTOR_NORMAL;
int result = (mg_value(v) * int(ph) + ev * int(128 - ph)) / 128;
- return Value(result & ~(GrainSize - 1));
+ return Value((result + GrainSize / 2) & ~(GrainSize - 1));
}
Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) {
// Scale option value from 100 to 256
- int mg = get_option_value_int(mgOpt) * 256 / 100;
- int eg = get_option_value_int(egOpt) * 256 / 100;
+ int mg = Options[mgOpt].value<int>() * 256 / 100;
+ int eg = Options[egOpt].value<int>() * 256 / 100;
return apply_weight(make_score(mg, eg), internalWeight);
}
for (int i = 0; i < 100; i++)
KingDangerTable[c][i] = apply_weight(make_score(t[i], 0), Weights[KingDangerUs + c]);
}
+
+
+ // 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) {
+
+ Score term_w = TracedTerms[WHITE][idx];
+ Score term_b = TracedTerms[BLACK][idx];
+
+ switch (idx) {
+ case PST: case IMBALANCE: case PAWN: case UNSTOPPABLE: case TOTAL:
+ TraceStream << std::setw(20) << name << " | --- --- | --- --- | "
+ << std::setw(6) << to_cp(mg_value(term_w)) << " "
+ << std::setw(6) << to_cp(eg_value(term_w)) << " \n";
+ break;
+ default:
+ TraceStream << std::setw(20) << name << " | " << std::noshowpos
+ << std::setw(5) << to_cp(mg_value(term_w)) << " "
+ << std::setw(5) << to_cp(eg_value(term_w)) << " | "
+ << std::setw(5) << to_cp(mg_value(term_b)) << " "
+ << std::setw(5) << to_cp(eg_value(term_b)) << " | "
+ << std::showpos
+ << std::setw(6) << to_cp(mg_value(term_w - term_b)) << " "
+ << std::setw(6) << to_cp(eg_value(term_w - term_b)) << " \n";
+ }
+ }
+}
+
+
+/// 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(TracedTerms, 0, 2 * 16 * sizeof(Score));
+
+ do_evaluate<false, 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