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/>.
19 //Definition of input features HalfKP of NNUE evaluation function
21 #ifndef NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED
22 #define NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED
24 #include "../nnue_common.h"
26 #include "../../evaluate.h"
27 #include "../../misc.h"
33 namespace Stockfish::Eval::NNUE::Features {
35 // Feature HalfKAv2_hm: Combination of the position of own king
36 // and the position of pieces. Position mirrored such that king always on e..h files.
39 // unique number for each piece type on each square
43 PS_B_PAWN = 1 * SQUARE_NB,
44 PS_W_KNIGHT = 2 * SQUARE_NB,
45 PS_B_KNIGHT = 3 * SQUARE_NB,
46 PS_W_BISHOP = 4 * SQUARE_NB,
47 PS_B_BISHOP = 5 * SQUARE_NB,
48 PS_W_ROOK = 6 * SQUARE_NB,
49 PS_B_ROOK = 7 * SQUARE_NB,
50 PS_W_QUEEN = 8 * SQUARE_NB,
51 PS_B_QUEEN = 9 * SQUARE_NB,
52 PS_KING = 10 * SQUARE_NB,
53 PS_NB = 11 * SQUARE_NB
56 static constexpr IndexType PieceSquareIndex[COLOR_NB][PIECE_NB] = {
57 // convention: W - us, B - them
58 // viewed from other side, W and B are reversed
59 { PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE,
60 PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE },
61 { PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE,
62 PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE }
65 // Orient a square according to perspective (rotates by 180 for black)
66 static Square orient(Color perspective, Square s, Square ksq);
68 // Index of a feature for a given king position and another piece on some square
69 static IndexType make_index(Color perspective, Square s, Piece pc, Square ksq);
73 static constexpr const char* Name = "HalfKAv2_hm(Friend)";
75 // Hash value embedded in the evaluation file
76 static constexpr std::uint32_t HashValue = 0x7f234cb8u;
78 // Number of feature dimensions
79 static constexpr IndexType Dimensions =
80 static_cast<IndexType>(SQUARE_NB) * static_cast<IndexType>(PS_NB) / 2;
82 static constexpr int KingBuckets[64] = {
83 -1, -1, -1, -1, 31, 30, 29, 28,
84 -1, -1, -1, -1, 27, 26, 25, 24,
85 -1, -1, -1, -1, 23, 22, 21, 20,
86 -1, -1, -1, -1, 19, 18, 17, 16,
87 -1, -1, -1, -1, 15, 14, 13, 12,
88 -1, -1, -1, -1, 11, 10, 9, 8,
89 -1, -1, -1, -1, 7, 6, 5, 4,
90 -1, -1, -1, -1, 3, 2, 1, 0
93 // Maximum number of simultaneously active features.
94 static constexpr IndexType MaxActiveDimensions = 32;
95 using IndexList = ValueList<IndexType, MaxActiveDimensions>;
97 // Get a list of indices for active features
98 static void append_active_indices(
103 // Get a list of indices for recently changed features
104 static void append_changed_indices(
106 const DirtyPiece& dp,
112 // Returns the cost of updating one perspective, the most costly one.
113 // Assumes no refresh needed.
114 static int update_cost(const StateInfo* st);
115 static int refresh_cost(const Position& pos);
117 // Returns whether the change stored in this StateInfo means that
118 // a full accumulator refresh is required.
119 static bool requires_refresh(const StateInfo* st, Color perspective);
122 } // namespace Stockfish::Eval::NNUE::Features
124 #endif // #ifndef NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED