#include "evaluate.h"
#include "material.h"
#include "pawns.h"
-#include "scale.h"
#include "thread.h"
#include "ucioption.h"
// ThreatBonus[attacking][attacked] contains bonus according to which
// piece type attacks which one.
const Score ThreatBonus[8][8] = {
- {},
- { S(0, 0), S(18,37), S( 0, 0), S(37,47), S(55,97), S(55,97) }, // KNIGHT
- { S(0, 0), S(18,37), S(37,47), S( 0, 0), S(55,97), S(55,97) }, // BISHOP
- { S(0, 0), S( 9,27), S(27,47), S(27,47), S( 0, 0), S(37,47) }, // ROOK
- { S(0, 0), S(27,37), S(27,37), S(27,37), S(27,37), S( 0, 0) }, // QUEEN
- {}, {}, {}
+ {}, {},
+ { 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(15, 39), S(15, 39), S(15, 39), S(15, 39), S( 0, 0) } // QUEEN
};
// ThreatedByPawnPenalty[] contains a penalty according to which piece
// Bonuses for enemy's safe checks
const int QueenContactCheckBonus = 3;
- const int DiscoveredCheckBonus = 3;
const int QueenCheckBonus = 2;
const int RookCheckBonus = 1;
const int BishopCheckBonus = 1;
const int KnightCheckBonus = 1;
- // Scan for queen contact mates?
- const bool QueenContactMates = true;
-
- // Bonus for having a mate threat
- const int MateThreatBonus = 3;
-
// InitKingDanger[] contains bonuses based on the position of the defending
// king.
const int InitKingDanger[64] = {
// Function prototypes
template<bool HasPopCnt>
- Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID);
+ Value do_evaluate(const Position& pos, EvalInfo& ei);
+
+ template<Color Us, bool HasPopCnt>
+ void init_attack_tables(const Position& pos, EvalInfo& ei);
template<Color Us, bool HasPopCnt>
void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei);
void evaluate_threats(const Position& pos, EvalInfo& ei);
template<Color Us, bool HasPopCnt>
- void evaluate_space(const Position& pos, EvalInfo& ei);
+ int evaluate_space(const Position& pos, EvalInfo& ei);
template<Color Us>
void evaluate_passed_pawns(const Position& pos, EvalInfo& ei);
/// 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, EvalInfo& ei, int threadID) {
+Value evaluate(const Position& pos, EvalInfo& ei) {
- return CpuHasPOPCNT ? do_evaluate<true>(pos, ei, threadID)
- : do_evaluate<false>(pos, ei, threadID);
+ return CpuHasPOPCNT ? do_evaluate<true>(pos, ei)
+ : do_evaluate<false>(pos, ei);
}
namespace {
template<bool HasPopCnt>
-Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) {
+Value do_evaluate(const Position& pos, EvalInfo& ei) {
- Bitboard b;
ScaleFactor factor[2];
assert(pos.is_ok());
- assert(threadID >= 0 && threadID < MAX_THREADS);
+ assert(pos.thread() >= 0 && pos.thread() < MAX_THREADS);
assert(!pos.is_check());
memset(&ei, 0, sizeof(EvalInfo));
ei.value = pos.value();
// Probe the material hash table
- ei.mi = MaterialTable[threadID]->get_material_info(pos);
+ ei.mi = MaterialTable[pos.thread()]->get_material_info(pos);
ei.value += ei.mi->material_value();
// If we have a specialized evaluation function for the current material
factor[BLACK] = ei.mi->scale_factor(pos, BLACK);
// Probe the pawn hash table
- ei.pi = PawnTable[threadID]->get_pawn_info(pos);
+ ei.pi = PawnTable[pos.thread()]->get_pawn_info(pos);
ei.value += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]);
- // Initialize king attack bitboards and king attack zones for both sides
- ei.attackedBy[WHITE][KING] = pos.attacks_from<KING>(pos.king_square(WHITE));
- ei.attackedBy[BLACK][KING] = pos.attacks_from<KING>(pos.king_square(BLACK));
- ei.kingZone[WHITE] = ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8);
- ei.kingZone[BLACK] = ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8);
-
- // Initialize pawn attack bitboards for both sides
- ei.attackedBy[WHITE][PAWN] = ei.pi->pawn_attacks(WHITE);
- b = ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING];
- if (b)
- ei.kingAttackersCount[WHITE] = count_1s_max_15<HasPopCnt>(b)/2;
-
- ei.attackedBy[BLACK][PAWN] = ei.pi->pawn_attacks(BLACK);
- b = ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING];
- if (b)
- ei.kingAttackersCount[BLACK] = count_1s_max_15<HasPopCnt>(b)/2;
+ // Initialize attack bitboards with pawns evaluation
+ init_attack_tables<WHITE, HasPopCnt>(pos, ei);
+ init_attack_tables<BLACK, HasPopCnt>(pos, ei);
// Evaluate pieces
evaluate_pieces_of_color<WHITE, HasPopCnt>(pos, ei);
// Middle-game specific evaluation terms
if (phase > PHASE_ENDGAME)
{
- // Pawn storms in positions with opposite castling
- if ( square_file(pos.king_square(WHITE)) >= FILE_E
- && square_file(pos.king_square(BLACK)) <= FILE_D)
+ // Pawn storms in positions with opposite castling
+ if ( square_file(pos.king_square(WHITE)) >= FILE_E
+ && square_file(pos.king_square(BLACK)) <= FILE_D)
- ei.value += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0);
+ ei.value += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0);
- else if ( square_file(pos.king_square(WHITE)) <= FILE_D
- && square_file(pos.king_square(BLACK)) >= FILE_E)
+ else if ( square_file(pos.king_square(WHITE)) <= FILE_D
+ && square_file(pos.king_square(BLACK)) >= FILE_E)
- ei.value += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0);
+ ei.value += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0);
- // Evaluate space for both sides
- if (ei.mi->space_weight() > 0)
- {
- evaluate_space<WHITE, HasPopCnt>(pos, ei);
- evaluate_space<BLACK, HasPopCnt>(pos, ei);
- }
+ // Evaluate space for both sides
+ if (ei.mi->space_weight() > 0)
+ {
+ int s = evaluate_space<WHITE, HasPopCnt>(pos, ei) - evaluate_space<BLACK, HasPopCnt>(pos, ei);
+ ei.value += apply_weight(make_score(s * ei.mi->space_weight(), 0), Weights[Space]);
+ }
}
// Mobility
}
// Interpolate between the middle game and the endgame score
- Color stm = pos.side_to_move();
-
- Value v = Sign[stm] * scale_by_game_phase(ei.value, phase, factor);
-
- return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v);
+ return Sign[pos.side_to_move()] * scale_by_game_phase(ei.value, phase, factor);
}
} // namespace
namespace {
+ // init_attack_tables() initializes king bitboards for both sides adding
+ // pawn attacks. To be done before other evaluations.
+
+ template<Color Us, bool HasPopCnt>
+ void init_attack_tables(const Position& pos, EvalInfo& ei) {
+
+ 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];
+ if (b)
+ ei.kingAttackersCount[Us] = count_1s_max_15<HasPopCnt>(b) / 2;
+ }
+
+
// evaluate_outposts() evaluates bishop and knight outposts squares
template<PieceType Piece, Color Us>
ei.value -= Sign[Us] * ThreatedByPawnPenalty[Piece];
// Bishop and knight outposts squares
- if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Them))
+ if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Us))
evaluate_outposts<Piece, Us>(pos, ei, s);
// Special patterns: trapped bishops on a7/h7/a2/h2
const Color Them = (Us == WHITE ? BLACK : WHITE);
- Bitboard undefended, attackedByOthers, escapeSquares, occ, b, b1, b2, safe;
- Square from, to;
+ Bitboard undefended, b, b1, b2, safe;
bool sente;
int attackUnits, shelter = 0;
const Square ksq = pos.king_square(Us);
// King safety. This is quite complicated, and is almost certainly far
// from optimally tuned.
if ( pos.piece_count(Them, QUEEN) >= 1
- && ei.kingAttackersCount[Them] >= 2
- && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame
+ && ei.kingAttackersCount[Them] >= 2
+ && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame
&& ei.kingAdjacentZoneAttacksCount[Them])
{
// Is it the attackers turn to move?
+ InitKingDanger[relative_square(Us, ksq)]
- shelter / 32;
- // Analyse safe queen contact checks
+ // Analyse enemy's safe queen contact checks. First find undefended
+ // squares around the king attacked by enemy queen...
b = undefended & ei.attacked_by(Them, QUEEN) & ~pos.pieces_of_color(Them);
if (b)
{
- attackedByOthers = ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT)
- | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK);
-
- b &= attackedByOthers;
-
- // Squares attacked by the queen and supported by another enemy piece and
- // not defended by other pieces but our king.
+ // ...then remove squares not supported by another enemy piece
+ b &= ( ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT)
+ | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK));
if (b)
- {
- // The bitboard b now contains the squares available for safe queen
- // contact checks.
attackUnits += QueenContactCheckBonus * count_1s_max_15<HasPopCnt>(b) * (sente ? 2 : 1);
-
- // Is there a mate threat?
- if (QueenContactMates && !pos.is_check())
- {
- escapeSquares = pos.attacks_from<KING>(ksq) & ~pos.pieces_of_color(Us) & ~attackedByOthers;
- occ = pos.occupied_squares();
- while (b)
- {
- to = pop_1st_bit(&b);
-
- // Do we have escape squares from queen contact check attack ?
- if (!(escapeSquares & ~queen_attacks_bb(to, occ & ClearMaskBB[ksq])))
- {
- // We have a mate, unless the queen is pinned or there
- // is an X-ray attack through the queen.
- for (int i = 0; i < pos.piece_count(Them, QUEEN); i++)
- {
- from = pos.piece_list(Them, QUEEN, i);
- if ( bit_is_set(pos.attacks_from<QUEEN>(from), to)
- && !bit_is_set(pos.pinned_pieces(Them), from)
- && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(ROOK, QUEEN, Us))
- && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(BISHOP, QUEEN, Us)))
-
- // Set the mate threat move
- ei.mateThreat[Them] = make_move(from, to);
- }
- }
- }
- }
- }
}
- // Analyse enemy's safe distance checks
+ // Analyse enemy's safe distance checks for sliders and knights
safe = ~(pos.pieces_of_color(Them) | ei.attacked_by(Us));
b1 = pos.attacks_from<ROOK>(ksq) & safe;
b2 = pos.attacks_from<BISHOP>(ksq) & safe;
+ // Enemy queen safe checks
+ b = (b1 | b2) & ei.attacked_by(Them, QUEEN);
+ if (b)
+ attackUnits += QueenCheckBonus * count_1s_max_15<HasPopCnt>(b);
+
// Enemy rooks safe checks
b = b1 & ei.attacked_by(Them, ROOK);
if (b)
if (b)
attackUnits += BishopCheckBonus * count_1s_max_15<HasPopCnt>(b);
- // Enemy queens safe checks
- b = (b1 | b2) & ei.attacked_by(Them, QUEEN);
- if (b)
- attackUnits += QueenCheckBonus * count_1s_max_15<HasPopCnt>(b);
-
// Enemy knights safe checks
b = pos.attacks_from<KNIGHT>(ksq) & ei.attacked_by(Them, KNIGHT) & safe;
if (b)
attackUnits += KnightCheckBonus * count_1s_max_15<HasPopCnt>(b);
- // Analyse discovered checks (only for non-pawns right now, consider
- // adding pawns later).
- b = pos.discovered_check_candidates(Them) & ~pos.pieces(PAWN);
- if (b)
- attackUnits += DiscoveredCheckBonus * count_1s_max_15<HasPopCnt>(b) * (sente ? 2 : 1);
-
- // Has a mate threat been found? We don't do anything here if the
- // side with the mating move is the side to move, because in that
- // case the mating side will get a huge bonus at the end of the main
- // evaluation function instead.
- if (ei.mateThreat[Them] != MOVE_NONE)
- attackUnits += MateThreatBonus;
-
- // Ensure that attackUnits is between 0 and 99, in order to avoid array
- // out of bounds errors.
+ // To index KingDangerTable[] attackUnits must be in [0, 99] range
attackUnits = Min(99, Max(0, attackUnits));
// Finally, extract the king danger score from the KingDangerTable[]
const Color Them = (Us == WHITE ? BLACK : WHITE);
+ Bitboard squaresToQueen, defendedSquares, unsafeSquares, supportingPawns;
Bitboard b = ei.pi->passed_pawns() & pos.pieces_of_color(Us);
while (b)
{
Square s = pop_1st_bit(&b);
- assert(pos.piece_on(s) == piece_of_color_and_type(Us, PAWN));
assert(pos.pawn_is_passed(Us, s));
int r = int(relative_rank(Us, s) - RANK_2);
- int tr = Max(0, r * (r - 1));
+ int tr = r * (r - 1);
// Base bonus based on rank
Value mbonus = Value(20 * tr);
Value ebonus = Value(10 + r * r * 10);
- // Adjust bonus based on king proximity
if (tr)
{
Square blockSq = s + pawn_push(Us);
+ // Adjust bonus based on kings proximity
ebonus -= Value(square_distance(pos.king_square(Us), blockSq) * 3 * tr);
ebonus -= Value(square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * 1 * tr);
ebonus += Value(square_distance(pos.king_square(Them), blockSq) * 6 * tr);
// If the pawn is free to advance, increase bonus
if (pos.square_is_empty(blockSq))
{
- // There are no enemy pawns in the pawn's path
- Bitboard b2 = squares_in_front_of(Us, s);
-
- assert((b2 & pos.pieces(PAWN, Them)) == EmptyBoardBB);
-
- // Squares attacked by us
- Bitboard b4 = b2 & ei.attacked_by(Us);
-
- // Squares attacked or occupied by enemy pieces
- Bitboard b3 = b2 & (ei.attacked_by(Them) | pos.pieces_of_color(Them));
+ squaresToQueen = squares_in_front_of(Us, s);
+ defendedSquares = squaresToQueen & ei.attacked_by(Us);
// If there is an enemy rook or queen attacking the pawn from behind,
- // add all X-ray attacks by the rook or queen.
+ // 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<QUEEN>(s)))
- b3 = b2;
+ unsafeSquares = squaresToQueen;
+ else
+ unsafeSquares = squaresToQueen & (ei.attacked_by(Them) | pos.pieces_of_color(Them));
- // Are any of the squares in the pawn's path attacked or occupied by the enemy?
- if (b3 == EmptyBoardBB)
- // No enemy attacks or pieces, huge bonus!
- // Even bigger if we protect the pawn's path
- ebonus += Value(tr * (b2 == b4 ? 17 : 15));
+ // 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(tr * (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(tr * ((b3 & b4) == b3 ? 13 : 8));
+ ebonus += Value(tr * ((unsafeSquares & defendedSquares) == unsafeSquares ? 13 : 8));
// At last, add a small bonus when there are no *friendly* pieces
// in the pawn's path.
- if ((b2 & pos.pieces_of_color(Us)) == EmptyBoardBB)
+ if (!(squaresToQueen & pos.pieces_of_color(Us)))
ebonus += Value(tr);
}
} // tr != 0
- // If the pawn is supported by a friendly pawn, increase bonus
- Bitboard b1 = pos.pieces(PAWN, Us) & neighboring_files_bb(s);
- if (b1 & rank_bb(s))
+ // 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) & neighboring_files_bb(s);
+ if (supportingPawns & rank_bb(s))
ebonus += Value(r * 20);
- else if (pos.attacks_from<PAWN>(s, Them) & b1)
+ else if (supportingPawns & rank_bb(s - pawn_push(Us)))
ebonus += Value(r * 12);
// Rook pawns are a special case: They are sometimes worse, and
// value if the other side has a rook or queen.
if (square_file(s) == FILE_A || square_file(s) == FILE_H)
{
- if ( pos.non_pawn_material(Them) <= KnightValueMidgame
- && pos.piece_count(Them, KNIGHT) <= 1)
+ if (pos.non_pawn_material(Them) <= KnightValueMidgame)
ebonus += ebonus / 4;
else if (pos.pieces(ROOK, QUEEN, Them))
ebonus -= ebonus / 4;
Square s = pop_1st_bit(&b);
Square queeningSquare = relative_square(c, make_square(square_file(s), RANK_8));
int d = square_distance(s, queeningSquare)
+ - int(relative_rank(c, s) == RANK_2) // Double pawn push
- square_distance(pos.king_square(opposite_color(c)), queeningSquare)
+ int(c != pos.side_to_move());
- if (d < 0)
+ // Do we protect the path to queening ?
+ bool pathDefended = (ei.attacked_by(c) & squares_in_front_of(c, s)) == squares_in_front_of(c, s);
+
+ if (d < 0 || pathDefended)
{
int mtg = RANK_8 - relative_rank(c, s);
int blockerCount = count_1s_max_15(squares_in_front_of(c, s) & pos.occupied_squares());
mtg += blockerCount;
d += blockerCount;
- if (d < 0 && (!movesToGo[c] || movesToGo[c] > mtg))
+ if ((d < 0 || pathDefended) && (!movesToGo[c] || movesToGo[c] > mtg))
{
movesToGo[c] = mtg;
pawnToGo[c] = s;
// twice. Finally, the space bonus is scaled by a weight taken from the
// material hash table.
template<Color Us, bool HasPopCnt>
- void evaluate_space(const Position& pos, EvalInfo& ei) {
+ int evaluate_space(const Position& pos, EvalInfo& ei) {
const Color Them = (Us == WHITE ? BLACK : WHITE);
// Find the safe squares for our pieces inside the area defined by
// SpaceMask[us]. 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)
+ & ~ei.attacked_by(Them, PAWN)
+ & (ei.attacked_by(Us) | ~ei.attacked_by(Them));
- Bitboard safeSquares = SpaceMask[Us]
- & ~pos.pieces(PAWN, Us)
- & ~ei.attacked_by(Them, PAWN)
- & ~(~ei.attacked_by(Us) & ei.attacked_by(Them));
+ // Find all squares which are at most three squares behind some friendly pawn
+ Bitboard behind = pos.pieces(PAWN, Us);
+ behind |= (Us == WHITE ? behind >> 8 : behind << 8);
+ behind |= (Us == WHITE ? behind >> 16 : behind << 16);
- // Find all squares which are at most three squares behind some friendly
- // pawn.
- Bitboard behindFriendlyPawns = pos.pieces(PAWN, Us);
- behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 8 : behindFriendlyPawns << 8);
- behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 16 : behindFriendlyPawns << 16);
-
- int space = count_1s_max_15<HasPopCnt>(safeSquares)
- + count_1s_max_15<HasPopCnt>(behindFriendlyPawns & safeSquares);
-
- ei.value += Sign[Us] * apply_weight(make_score(space * ei.mi->space_weight(), 0), Weights[Space]);
+ return count_1s_max_15<HasPopCnt>(safe) + count_1s_max_15<HasPopCnt>(behind & safe);
}
assert(eg_value(v) > -VALUE_INFINITE && eg_value(v) < VALUE_INFINITE);
assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
- Value ev = apply_scale_factor(eg_value(v), sf[(eg_value(v) > Value(0) ? WHITE : BLACK)]);
+ Value eg = eg_value(v);
+ ScaleFactor f = sf[eg > Value(0) ? WHITE : BLACK];
+ Value ev = Value((eg * f) / int(SCALE_FACTOR_NORMAL));
int result = (mg_value(v) * ph + ev * (128 - ph)) / 128;
return Value(result & ~(GrainSize - 1));
Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) {
- Score uciWeight = make_score(get_option_value_int(mgOpt), get_option_value_int(egOpt));
-
- // Convert to integer to prevent overflow
- int mg = mg_value(uciWeight);
- int eg = eg_value(uciWeight);
+ // 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;
- mg = (mg * 0x100) / 100;
- eg = (eg * 0x100) / 100;
- mg = (mg * mg_value(internalWeight)) / 0x100;
- eg = (eg * eg_value(internalWeight)) / 0x100;
- return make_score(mg, eg);
+ return apply_weight(make_score(mg, eg), internalWeight);
}
// init_safety() initizes the king safety evaluation, based on UCI
void init_safety() {
- int maxSlope = 30;
- int peak = 0x500;
- double a = 0.4;
- double b = 0.0;
+ const Value MaxSlope = Value(30);
+ const Value Peak = Value(1280);
Value t[100];
// First setup the base table
for (int i = 0; i < 100; i++)
{
- if (i < b)
- t[i] = Value(0);
- else
- t[i] = Value((int)(a * (i - b) * (i - b)));
- }
+ t[i] = Value(int(0.4 * i * i));
- for (int i = 1; i < 100; i++)
- {
- if (t[i] - t[i - 1] > maxSlope)
- t[i] = t[i - 1] + Value(maxSlope);
+ if (i > 0)
+ t[i] = Min(t[i], t[i - 1] + MaxSlope);
- if (t[i] > Value(peak))
- t[i] = Value(peak);
+ t[i] = Min(t[i], Peak);
}
// Then apply the weights and get the final KingDangerTable[] array
projects / stockfish / blobdiff