#define V Value
#define S(mg, eg) make_score(mg, eg)
- // Doubled pawn penalty by file
- const Score Doubled[FILE_NB] = {
- S(13, 43), S(20, 48), S(23, 48), S(23, 48),
- S(23, 48), S(23, 48), S(20, 48), S(13, 43) };
-
// Isolated pawn penalty by opposed flag and file
const Score Isolated[2][FILE_NB] = {
- { S(37, 45), S(54, 52), S(60, 52), S(60, 52),
- S(60, 52), S(60, 52), S(54, 52), S(37, 45) },
- { S(25, 30), S(36, 35), S(40, 35), S(40, 35),
- S(40, 35), S(40, 35), S(36, 35), S(25, 30) } };
-
- // Backward pawn penalty by opposed flag and file
- const Score Backward[2][FILE_NB] = {
- { S(30, 42), S(43, 46), S(49, 46), S(49, 46),
- S(49, 46), S(49, 46), S(43, 46), S(30, 42) },
- { S(20, 28), S(29, 31), S(33, 31), S(33, 31),
- S(33, 31), S(33, 31), S(29, 31), S(20, 28) } };
+ { S(37, 45), S(54, 52), S(60, 52), S(60, 52),
+ S(60, 52), S(60, 52), S(54, 52), S(37, 45) },
+ { S(25, 30), S(36, 35), S(40, 35), S(40, 35),
+ S(40, 35), S(40, 35), S(36, 35), S(25, 30) } };
+
+ // Backward pawn penalty by opposed flag
+ const Score Backward[2] = { S(67, 42), S(49, 24) };
+
+ // Unsupported pawn penalty, for pawns which are neither isolated or backward
+ const Score Unsupported = S(20, 10);
// Connected pawn bonus by opposed, phalanx, twice supported and rank
Score Connected[2][2][2][RANK_NB];
+
+ // Doubled pawn penalty by file
+ const Score Doubled[FILE_NB] = {
+ S(13, 43), S(20, 48), S(23, 48), S(23, 48),
+ S(23, 48), S(23, 48), S(20, 48), S(13, 43) };
- // Levers bonus by rank
+ // Lever bonus by rank
const Score Lever[RANK_NB] = {
- S( 0, 0), S( 0, 0), S(0, 0), S(0, 0),
- S(20,20), S(40,40), S(0, 0), S(0, 0) };
-
- // Unsupported pawn penalty
- const Score UnsupportedPawnPenalty = S(20, 10);
-
- // Center bind bonus: Two pawns controlling the same central square
- const Bitboard CenterBindMask[COLOR_NB] = {
- (FileDBB | FileEBB) & (Rank5BB | Rank6BB | Rank7BB),
- (FileDBB | FileEBB) & (Rank4BB | Rank3BB | Rank2BB)
- };
+ S( 0, 0), S( 0, 0), S(0, 0), S(0, 0),
+ S(20, 20), S(40, 40), S(0, 0), S(0, 0) };
+ // Center bind bonus, when two pawns controls the same central square
const Score CenterBind = S(16, 0);
// Weakness of our pawn shelter in front of the king by [distance from edge][rank]
const Value ShelterWeakness[][RANK_NB] = {
- { V( 99), V(20), V(26), V(54), V(85), V( 92), V(108) },
- { V(117), V( 1), V(27), V(71), V(94), V(104), V(118) },
- { V(104), V( 4), V(51), V(76), V(82), V(102), V( 97) },
- { V( 80), V(12), V(43), V(65), V(88), V( 91), V(115) } };
+ { V( 97), V(21), V(26), V(51), V(87), V( 89), V( 99) },
+ { V(120), V( 0), V(28), V(76), V(88), V(103), V(104) },
+ { V(101), V( 7), V(54), V(78), V(77), V( 92), V(101) },
+ { V( 80), V(11), V(44), V(68), V(87), V( 90), V(119) } };
// Danger of enemy pawns moving toward our king by [type][distance from edge][rank]
const Value StormDanger[][4][RANK_NB] = {
- { { V( 0), V( 65), V( 126), V(36), V(30) },
- { V( 0), V( 55), V( 135), V(36), V(23) },
- { V( 0), V( 47), V( 116), V(45), V(26) },
- { V( 0), V( 62), V( 127), V(57), V(34) } },
- { { V(21), V( 45), V( 93), V(50), V(19) },
- { V(23), V( 24), V( 105), V(41), V(13) },
- { V(23), V( 36), V( 101), V(38), V(20) },
- { V(30), V( 19), V( 110), V(41), V(27) } },
- { { V( 0), V( 0), V( 81), V(14), V( 4) },
- { V( 0), V( 0), V( 169), V(30), V( 3) },
- { V( 0), V( 0), V( 168), V(24), V( 5) },
- { V( 0), V( 0), V( 162), V(26), V(10) } },
- { { V( 0), V(-283), V(-298), V(57), V(29) },
- { V( 0), V( 63), V( 137), V(42), V(18) },
- { V( 0), V( 67), V( 145), V(49), V(33) },
- { V( 0), V( 62), V( 126), V(53), V(21) } } };
+ { { V( 0), V( 67), V( 134), V(38), V(32) },
+ { V( 0), V( 57), V( 139), V(37), V(22) },
+ { V( 0), V( 43), V( 115), V(43), V(27) },
+ { V( 0), V( 68), V( 124), V(57), V(32) } },
+ { { V(20), V( 43), V( 100), V(56), V(20) },
+ { V(23), V( 20), V( 98), V(40), V(15) },
+ { V(23), V( 39), V( 103), V(36), V(18) },
+ { V(28), V( 19), V( 108), V(42), V(26) } },
+ { { V( 0), V( 0), V( 75), V(14), V( 2) },
+ { V( 0), V( 0), V( 150), V(30), V( 4) },
+ { V( 0), V( 0), V( 160), V(22), V( 5) },
+ { V( 0), V( 0), V( 166), V(24), V(13) } },
+ { { V( 0), V(-283), V(-281), V(57), V(31) },
+ { V( 0), V( 58), V( 141), V(39), V(18) },
+ { V( 0), V( 65), V( 142), V(48), V(32) },
+ { V( 0), V( 60), V( 126), V(51), V(19) } } };
// Max bonus for king safety. Corresponds to start position with all the pawns
// in front of the king and no enemy pawn on the horizon.
const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW);
const Square Left = (Us == WHITE ? DELTA_NW : DELTA_SE);
+ const Bitboard CenterBindMask =
+ Us == WHITE ? (FileDBB | FileEBB) & (Rank5BB | Rank6BB | Rank7BB)
+ : (FileDBB | FileEBB) & (Rank4BB | Rank3BB | Rank2BB);
+
Bitboard b, neighbours, doubled, supported, phalanx;
Square s;
bool passed, isolated, opposed, backward, lever, connected;
Score score = SCORE_ZERO;
- const Square* pl = pos.
list<PAWN>(Us);
+ const Square* pl = pos.
squares<PAWN>(Us);
const Bitboard* pawnAttacksBB = StepAttacksBB[make_piece(Us, PAWN)];
Bitboard ourPawns = pos.pieces(Us , PAWN);
Bitboard theirPawns = pos.pieces(Them, PAWN);
- e->passedPawns[Us] = 0;
+ e->passedPawns[Us] = e->pawnAttacksSpan[Us] = 0;
e->kingSquares[Us] = SQ_NONE;
e->semiopenFiles[Us] = 0xFF;
e->pawnAttacks[Us] = shift_bb<Right>(ourPawns) | shift_bb<Left>(ourPawns);
File f = file_of(s);
- // This file cannot be semi-open
e->semiopenFiles[Us] &= ~(1 << f);
+ e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s);
// Flag the pawn
neighbours = ourPawns & adjacent_files_bb(f);
// Test for backward pawn.
// If the pawn is passed, isolated, lever or connected it cannot be
// backward. If there are friendly pawns behind on adjacent files
- // it cannot be backward either.
+ // or if it is sufficiently advanced, it cannot be backward either.
if ( (passed | isolated | lever | connected)
- || (ourPawns & pawn_attack_span(Them, s)))
+ || (ourPawns & pawn_attack_span(Them, s))
+ || (relative_rank(Us, s) >= RANK_5))
backward = false;
else
{
assert(opposed | passed | (pawn_attack_span(Us, s) & theirPawns));
// Passed pawns will be properly scored in evaluation because we need
- // full attack info to evaluate passed pawns. Only the frontmost passed
+ // full attack info to evaluate them. Only the frontmost passed
// pawn on each file is considered a true passed pawn.
if (passed && !doubled)
e->passedPawns[Us] |= s;
if (isolated)
score -= Isolated[opposed][f];
- if (!supported && !isolated)
- score -= UnsupportedPawnPenalty;
+ else if (backward)
+ score -= Backward[opposed];
- if (doubled)
- score -= Doubled[f] / distance<Rank>(s, frontmost_sq(Us, doubled));
-
- if (backward)
- score -= Backward[opposed][f];
+ else if (!supported)
+ score -= Unsupported;
if (connected)
score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)];
+ if (doubled)
+ score -= Doubled[f] / distance<Rank>(s, frontmost_sq(Us, doubled));
+
if (lever)
score += Lever[relative_rank(Us, s)];
}
b = e->semiopenFiles[Us] ^ 0xFF;
e->pawnSpan[Us] = b ? int(msb(b) - lsb(b)) : 0;
- // Center binds: Two pawns controlling the same central square
- b = shift_bb<Right>(ourPawns) & shift_bb<Left>(ourPawns) & CenterBindMask[Us];
- score += popcount<Max15>(b) * CenterBind;
+ b = shift_bb<Right>(ourPawns) & shift_bb<Left>(ourPawns) & CenterBindMask;
+ score += CenterBind * popcount<Max15>(b);
return score;
}
e->key = key;
e->score = evaluate<WHITE>(pos, e) - evaluate<BLACK>(pos, e);
+ e->asymmetry = popcount<Max15>(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
return e;
}
projects / stockfish / blobdiff