- { 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) }};
-
- // Pawn chain membership bonus by file
- const Score ChainMember[FILE_NB][RANK_NB] = {
- { S(0, 0), S(14, 0), S(16, 4), S(18, 9), S(28, 28), S(52, 104), S(118, 236) },
- { S(0, 0), S(16, 0), S(18, 5), S(20, 10), S(30, 30), S(54, 108), S(120, 240) },
- { S(0, 0), S(16, 0), S(18, 5), S(20, 10), S(30, 30), S(54, 108), S(120, 240) },
- { S(0, 0), S(17, 0), S(19, 6), S(22, 11), S(33, 33), S(59, 118), S(127, 254) },
- { S(0, 0), S(17, 0), S(19, 6), S(22, 11), S(33, 33), S(59, 118), S(127, 254) },
- { S(0, 0), S(16, 0), S(18, 5), S(20, 10), S(30, 30), S(54, 108), S(120, 240) },
- { S(0, 0), S(16, 0), S(18, 5), S(20, 10), S(30, 30), S(54, 108), S(120, 240) },
- { S(0, 0), S(14, 0), S(16, 4), S(18, 9), S(28, 28), S(52, 104), S(118, 236) }};
-
- // Candidate passed pawn bonus by rank
- const Score CandidatePassed[RANK_NB] = {
- S( 0, 0), S( 6, 13), S(6,13), S(14,29),
- S(34,68), S(83,166), S(0, 0), S( 0, 0)
+ { S(50, 52), S(63, 56), S(69, 56), S(69, 56),
+ S(69, 56), S(69, 56), S(63, 56), S(50, 52) },
+ { S(40, 38), S(49, 41), S(53, 41), S(53, 41),
+ S(53, 41), S(53, 41), S(49, 41), S(40, 38) } };
+
+ // Connected pawn bonus by opposed, phalanx, twice supported and rank
+ Score Connected[2][2][2][RANK_NB];
+
+ // Levers 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)