2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
5 Stockfish is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
10 Stockfish is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
31 auto constexpr S = make_score;
33 // 'Bonus' contains Piece-Square parameters.
34 // Scores are explicit for files A to D, implicitly mirrored for E to H.
35 constexpr Score Bonus[][RANK_NB][int(FILE_NB) / 2] = {
39 { S(-175, -96), S(-92,-65), S(-74,-49), S(-73,-21) },
40 { S( -77, -67), S(-41,-54), S(-27,-18), S(-15, 8) },
41 { S( -61, -40), S(-17,-27), S( 6, -8), S( 12, 29) },
42 { S( -35, -35), S( 8, -2), S( 40, 13), S( 49, 28) },
43 { S( -34, -45), S( 13,-16), S( 44, 9), S( 51, 39) },
44 { S( -9, -51), S( 22,-44), S( 58,-16), S( 53, 17) },
45 { S( -67, -69), S(-27,-50), S( 4,-51), S( 37, 12) },
46 { S(-201,-100), S(-83,-88), S(-56,-56), S(-26,-17) }
49 { S(-37,-40), S(-4 ,-21), S( -6,-26), S(-16, -8) },
50 { S(-11,-26), S( 6, -9), S( 13,-12), S( 3, 1) },
51 { S(-5 ,-11), S( 15, -1), S( -4, -1), S( 12, 7) },
52 { S(-4 ,-14), S( 8, -4), S( 18, 0), S( 27, 12) },
53 { S(-8 ,-12), S( 20, -1), S( 15,-10), S( 22, 11) },
54 { S(-11,-21), S( 4, 4), S( 1, 3), S( 8, 4) },
55 { S(-12,-22), S(-10,-14), S( 4, -1), S( 0, 1) },
56 { S(-34,-32), S( 1,-29), S(-10,-26), S(-16,-17) }
59 { S(-31, -9), S(-20,-13), S(-14,-10), S(-5, -9) },
60 { S(-21,-12), S(-13, -9), S( -8, -1), S( 6, -2) },
61 { S(-25, 6), S(-11, -8), S( -1, -2), S( 3, -6) },
62 { S(-13, -6), S( -5, 1), S( -4, -9), S(-6, 7) },
63 { S(-27, -5), S(-15, 8), S( -4, 7), S( 3, -6) },
64 { S(-22, 6), S( -2, 1), S( 6, -7), S(12, 10) },
65 { S( -2, 4), S( 12, 5), S( 16, 20), S(18, -5) },
66 { S(-17, 18), S(-19, 0), S( -1, 19), S( 9, 13) }
69 { S( 3,-69), S(-5,-57), S(-5,-47), S( 4,-26) },
70 { S(-3,-55), S( 5,-31), S( 8,-22), S(12, -4) },
71 { S(-3,-39), S( 6,-18), S(13, -9), S( 7, 3) },
72 { S( 4,-23), S( 5, -3), S( 9, 13), S( 8, 24) },
73 { S( 0,-29), S(14, -6), S(12, 9), S( 5, 21) },
74 { S(-4,-38), S(10,-18), S( 6,-12), S( 8, 1) },
75 { S(-5,-50), S( 6,-27), S(10,-24), S( 8, -8) },
76 { S(-2,-75), S(-2,-52), S( 1,-43), S(-2,-36) }
79 { S(271, 1), S(327, 45), S(271, 85), S(198, 76) },
80 { S(278, 53), S(303,100), S(234,133), S(179,135) },
81 { S(195, 88), S(258,130), S(169,169), S(120,175) },
82 { S(164,103), S(190,156), S(138,172), S( 98,172) },
83 { S(154, 96), S(179,166), S(105,199), S( 70,199) },
84 { S(123, 92), S(145,172), S( 81,184), S( 31,191) },
85 { S( 88, 47), S(120,121), S( 65,116), S( 33,131) },
86 { S( 59, 11), S( 89, 59), S( 45, 73), S( -1, 78) }
90 constexpr Score PBonus[RANK_NB][FILE_NB] =
91 { // Pawn (asymmetric distribution)
93 { S( 3,-10), S( 3, -6), S( 10, 10), S( 19, 0), S( 16, 14), S( 19, 7), S( 7, -5), S( -5,-19) },
94 { S( -9,-10), S(-15,-10), S( 11,-10), S( 15, 4), S( 32, 4), S( 22, 3), S( 5, -6), S(-22, -4) },
95 { S( -4, 6), S(-23, -2), S( 6, -8), S( 20, -4), S( 40,-13), S( 17,-12), S( 4,-10), S( -8, -9) },
96 { S( 13, 10), S( 0, 5), S(-13, 4), S( 1, -5), S( 11, -5), S( -2, -5), S(-13, 14), S( 5, 9) },
97 { S( 5, 28), S(-12, 20), S( -7, 21), S( 22, 28), S( -8, 30), S( -5, 7), S(-15, 6), S( -8, 13) },
98 { S( -7, 0), S( 7,-11), S( -3, 12), S(-13, 21), S( 5, 25), S(-16, 19), S( 10, 4), S( -8, 7) }
107 Score psq[PIECE_NB][SQUARE_NB];
109 // PSQT::init() initializes piece-square tables: the white halves of the tables are
110 // copied from Bonus[] and PBonus[], adding the piece value, then the black halves of
111 // the tables are initialized by flipping and changing the sign of the white scores.
114 for (Piece pc : {W_PAWN, W_KNIGHT, W_BISHOP, W_ROOK, W_QUEEN, W_KING})
116 Score score = make_score(PieceValue[MG][pc], PieceValue[EG][pc]);
118 for (Square s = SQ_A1; s <= SQ_H8; ++s)
120 File f = File(edge_distance(file_of(s)));
121 psq[ pc][s] = score + (type_of(pc) == PAWN ? PBonus[rank_of(s)][file_of(s)]
122 : Bonus[pc][rank_of(s)][f]);
123 psq[~pc][flip_rank(s)] = -psq[pc][s];