// Backward pawn penalty by opposed flag
const Score Backward[2] = { S(56, 33), S(41, 19) };
- // Unsupported pawn penalty for pawns which are neither isolated or backward,
- // by number of pawns it supports [less than 2 / exactly 2].
- const Score Unsupported[2] = { S(17, 8), S(21, 12) };
+ // Unsupported pawn penalty for pawns which are neither isolated or backward
+ const Score Unsupported = S(17, 8);
// Connected pawn bonus by opposed, phalanx, twice supported and rank
Score Connected[2][2][2][RANK_NB];
// Lever bonus by rank
const Score Lever[RANK_NB] = {
S( 0, 0), S( 0, 0), S(0, 0), S(0, 0),
- S(17, 16), S(33, 32), S(0, 0), S(0, 0) };
+ S(17, 16), S(33, 32), S(0, 0), S(0, 0)
+ };
// Weakness of our pawn shelter in front of the king by [distance from edge][rank]
const Value ShelterWeakness[][RANK_NB] = {
{ 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) } };
+ { 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(-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) } } };
+ { 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.
template<Color Us>
Score evaluate(const Position& pos, Pawns::Entry* e) {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Square Up = (Us == WHITE ? DELTA_N : DELTA_S);
- const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW);
- const Square Left = (Us == WHITE ? DELTA_NW : DELTA_SE);
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+ const Square Up = (Us == WHITE ? NORTH : SOUTH);
+ const Square Right = (Us == WHITE ? NORTH_EAST : SOUTH_WEST);
+ const Square Left = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
Bitboard b, neighbours, stoppers, doubled, supported, phalanx;
Square s;
Bitboard ourPawns = pos.pieces(Us , PAWN);
Bitboard theirPawns = pos.pieces(Them, PAWN);
- e->passedPawns[Us] = e->pawnAttacksSpan[Us] = 0;
- e->kingSquares[Us] = SQ_NONE;
+ e->passedPawns[Us] = e->pawnAttacksSpan[Us] = 0;
e->semiopenFiles[Us] = 0xFF;
- e->pawnAttacks[Us] = shift_bb<Right>(ourPawns) | shift_bb<Left>(ourPawns);
+ e->kingSquares[Us] = SQ_NONE;
+ e->pawnAttacks[Us] = shift<Right>(ourPawns) | shift<Left>(ourPawns);
e->pawnsOnSquares[Us][BLACK] = popcount(ourPawns & DarkSquares);
e->pawnsOnSquares[Us][WHITE] = pos.count<PAWN>(Us) - e->pawnsOnSquares[Us][BLACK];
File f = file_of(s);
- e->semiopenFiles[Us] &= ~(1 << f);
+ e->semiopenFiles[Us] &= ~(1 << f);
e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s);
// Flag the pawn
// The pawn is backward when it cannot safely progress to that rank:
// either there is a stopper in the way on this rank, or there is a
// stopper on adjacent file which controls the way to that rank.
- backward = (b | shift_bb<Up>(b & adjacent_files_bb(f))) & stoppers;
+ backward = (b | shift<Up>(b & adjacent_files_bb(f))) & stoppers;
assert(!backward || !(pawn_attack_span(Them, s + Up) & neighbours));
}
score -= Backward[opposed];
else if (!supported)
- score -= Unsupported[more_than_one(neighbours & pawnAttacksBB[s])];
+ score -= Unsupported;
if (connected)
score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)];
/// hard-coded tables, when makes sense, we prefer to calculate them with a formula
/// to reduce independent parameters and to allow easier tuning and better insight.
-void init()
-{
+void init() {
+
static const int Seed[RANK_NB] = { 0, 8, 19, 13, 71, 94, 169, 324 };
for (int opposed = 0; opposed <= 1; ++opposed)
e->key = key;
e->score = evaluate<WHITE>(pos, e) - evaluate<BLACK>(pos, e);
e->asymmetry = popcount(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
+ e->openFiles = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
return e;
}