namespace {
- const Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB;
- const Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB;
- const Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB;
- const Bitboard Center = (FileDBB | FileEBB) & (Rank4BB | Rank5BB);
+ constexpr Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB;
+ constexpr Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB;
+ constexpr Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB;
+ constexpr Bitboard Center = (FileDBB | FileEBB) & (Rank4BB | Rank5BB);
- const Bitboard KingFlank[FILE_NB] = {
+ constexpr Bitboard KingFlank[FILE_NB] = {
QueenSide, QueenSide, QueenSide,
CenterFiles, CenterFiles,
KingSide, KingSide, KingSide
};
// Threshold for lazy and space evaluation
- const Value LazyThreshold = Value(1500);
- const Value SpaceThreshold = Value(12222);
+ constexpr Value LazyThreshold = Value(1500);
+ constexpr Value SpaceThreshold = Value(12222);
// KingAttackWeights[PieceType] contains king attack weights by piece type
- const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 };
+ constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 };
// Penalties for enemy's safe checks
- const int QueenSafeCheck = 780;
- const int RookSafeCheck = 880;
- const int BishopSafeCheck = 435;
- const int KnightSafeCheck = 790;
+ constexpr int QueenSafeCheck = 780;
+ constexpr int RookSafeCheck = 880;
+ constexpr int BishopSafeCheck = 435;
+ constexpr int KnightSafeCheck = 790;
#define S(mg, eg) make_score(mg, eg)
// MobilityBonus[PieceType-2][attacked] contains bonuses for middle and end game,
// indexed by piece type and number of attacked squares in the mobility area.
- const Score MobilityBonus[][32] = {
+ constexpr Score MobilityBonus[][32] = {
{ S(-75,-76), S(-57,-54), S( -9,-28), S( -2,-10), S( 6, 5), S( 14, 12), // Knights
S( 22, 26), S( 29, 29), S( 36, 29) },
{ S(-48,-59), S(-20,-23), S( 16, -3), S( 26, 13), S( 38, 24), S( 51, 42), // Bishops
// Outpost[knight/bishop][supported by pawn] contains bonuses for minor
// pieces if they occupy or can reach an outpost square, bigger if that
// square is supported by a pawn.
- const Score Outpost[][2] = {
+ constexpr Score Outpost[][2] = {
{ S(22, 6), S(36,12) }, // Knight
{ S( 9, 2), S(15, 5) } // Bishop
};
// RookOnFile[semiopen/open] contains bonuses for each rook when there is
// no (friendly) pawn on the rook file.
- const Score RookOnFile[] = { S(20, 7), S(45, 20) };
+ constexpr Score RookOnFile[] = { S(20, 7), S(45, 20) };
// ThreatByMinor/ByRook[attacked PieceType] contains bonuses according to
// which piece type attacks which one. Attacks on lesser pieces which are
// pawn-defended are not considered.
- const Score ThreatByMinor[PIECE_TYPE_NB] = {
+ constexpr Score ThreatByMinor[PIECE_TYPE_NB] = {
S(0, 0), S(0, 31), S(39, 42), S(57, 44), S(68, 112), S(47, 120)
};
- const Score ThreatByRook[PIECE_TYPE_NB] = {
+ constexpr Score ThreatByRook[PIECE_TYPE_NB] = {
S(0, 0), S(0, 24), S(38, 71), S(38, 61), S(0, 38), S(36, 38)
};
// ThreatByKing[on one/on many] contains bonuses for king attacks on
// pawns or pieces which are not pawn-defended.
- const Score ThreatByKing[] = { S(3, 65), S(9, 145) };
+ constexpr Score ThreatByKing[] = { S(3, 65), S(9, 145) };
// PassedRank[Rank] contains a bonus according to the rank of a passed pawn
- const Score PassedRank[RANK_NB] = {
+ constexpr Score PassedRank[RANK_NB] = {
S(0, 0), S(5, 7), S(5, 13), S(32, 42), S(70, 70), S(172, 170), S(217, 269)
};
// PassedFile[File] contains a bonus according to the file of a passed pawn
- const Score PassedFile[FILE_NB] = {
+ constexpr Score PassedFile[FILE_NB] = {
S( 9, 10), S(2, 10), S(1, -8), S(-20,-12),
S(-20,-12), S(1, -8), S(2, 10), S( 9, 10)
};
// PassedDanger[Rank] contains a term to weight the passed score
- const int PassedDanger[RANK_NB] = { 0, 0, 0, 2, 7, 12, 19 };
+ constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 2, 7, 12, 19 };
// KingProtector[PieceType-2] contains a penalty according to distance from king
- const Score KingProtector[] = { S(3, 5), S(4, 3), S(3, 0), S(1, -1) };
+ constexpr Score KingProtector[] = { S(3, 5), S(4, 3), S(3, 0), S(1, -1) };
// Assorted bonuses and penalties
- const Score BishopPawns = S( 8, 12);
- const Score CloseEnemies = S( 7, 0);
- const Score Connectivity = S( 3, 1);
- const Score CorneredBishop = S( 50, 50);
- const Score Hanging = S( 52, 30);
- const Score HinderPassedPawn = S( 8, 1);
- const Score KnightOnQueen = S( 21, 11);
- const Score LongDiagonalBishop = S( 22, 0);
- const Score MinorBehindPawn = S( 16, 0);
- const Score PawnlessFlank = S( 20, 80);
- const Score RookOnPawn = S( 8, 24);
- const Score SliderOnQueen = S( 42, 21);
- const Score ThreatByPawnPush = S( 47, 26);
- const Score ThreatByRank = S( 16, 3);
- const Score ThreatBySafePawn = S(175,168);
- const Score TrappedRook = S( 92, 0);
- const Score WeakQueen = S( 50, 10);
- const Score WeakUnopposedPawn = S( 5, 25);
+ constexpr Score BishopPawns = S( 8, 12);
+ constexpr Score CloseEnemies = S( 7, 0);
+ constexpr Score Connectivity = S( 3, 1);
+ constexpr Score CorneredBishop = S( 50, 50);
+ constexpr Score Hanging = S( 52, 30);
+ constexpr Score HinderPassedPawn = S( 8, 1);
+ constexpr Score KnightOnQueen = S( 21, 11);
+ constexpr Score LongDiagonalBishop = S( 22, 0);
+ constexpr Score MinorBehindPawn = S( 16, 0);
+ constexpr Score PawnlessFlank = S( 20, 80);
+ constexpr Score RookOnPawn = S( 8, 24);
+ constexpr Score SliderOnQueen = S( 42, 21);
+ constexpr Score ThreatByPawnPush = S( 47, 26);
+ constexpr Score ThreatByRank = S( 16, 3);
+ constexpr Score ThreatBySafePawn = S(175,168);
+ constexpr Score TrappedRook = S( 92, 0);
+ constexpr Score WeakQueen = S( 50, 10);
+ constexpr Score WeakUnopposedPawn = S( 5, 25);
#undef S
template<Tracing T> template<Color Us>
void Evaluation<T>::initialize() {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Direction Up = (Us == WHITE ? NORTH : SOUTH);
- const Direction Down = (Us == WHITE ? SOUTH : NORTH);
- const Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB: Rank7BB | Rank6BB);
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH);
+ constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
+ constexpr Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB: Rank7BB | Rank6BB);
// Find our pawns that are blocked or on the first two ranks
Bitboard b = pos.pieces(Us, PAWN) & (shift<Down>(pos.pieces()) | LowRanks);
template<Tracing T> template<Color Us, PieceType Pt>
Score Evaluation<T>::pieces() {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB
: Rank5BB | Rank4BB | Rank3BB);
const Square* pl = pos.squares<Pt>(Us);
template<Tracing T> template<Color Us>
Score Evaluation<T>::king() const {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB
: AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB);
const Square ksq = pos.square<KING>(Us);
template<Tracing T> template<Color Us>
Score Evaluation<T>::threats() const {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Direction Up = (Us == WHITE ? NORTH : SOUTH);
- const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH);
+ constexpr Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safeThreats;
Score score = SCORE_ZERO;
template<Tracing T> template<Color Us>
Score Evaluation<T>::passed() const {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Direction Up = (Us == WHITE ? NORTH : SOUTH);
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH);
auto king_proximity = [&](Color c, Square s) {
return std::min(distance(pos.square<KING>(c), s), 5);
template<Tracing T> template<Color Us>
Score Evaluation<T>::space() const {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Bitboard SpaceMask =
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Bitboard SpaceMask =
Us == WHITE ? CenterFiles & (Rank2BB | Rank3BB | Rank4BB)
: CenterFiles & (Rank7BB | Rank6BB | Rank5BB);