git.sesse.net Git - stockfish/blob - src/nnue/features/half_ka_v2_hm.cpp

   1 /*
   2   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   3   Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
   4
   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.
   9
  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.
  14
  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/>.
  17 */
  18
  19 //Definition of input features HalfKAv2_hm of NNUE evaluation function
  20
  21 #include "half_ka_v2_hm.h"
  22
  23 #include "../../bitboard.h"
  24 #include "../../position.h"
  25 #include "../../types.h"
  26 #include "../nnue_common.h"
  27
  28 namespace Stockfish::Eval::NNUE::Features {
  29
  30 // Index of a feature for a given king position and another piece on some square
  31 template<Color Perspective>
  32 inline IndexType HalfKAv2_hm::make_index(Square s, Piece pc, Square ksq) {
  33     return IndexType((int(s) ^ OrientTBL[Perspective][ksq]) + PieceSquareIndex[Perspective][pc]
  34                      + KingBuckets[Perspective][ksq]);
  35 }
  36
  37 // Get a list of indices for active features
  38 template<Color Perspective>
  39 void HalfKAv2_hm::append_active_indices(const Position& pos, IndexList& active) {
  40     Square   ksq = pos.square<KING>(Perspective);
  41     Bitboard bb  = pos.pieces();
  42     while (bb)
  43     {
  44         Square s = pop_lsb(bb);
  45         active.push_back(make_index<Perspective>(s, pos.piece_on(s), ksq));
  46     }
  47 }
  48
  49 // Explicit template instantiations
  50 template void HalfKAv2_hm::append_active_indices<WHITE>(const Position& pos, IndexList& active);
  51 template void HalfKAv2_hm::append_active_indices<BLACK>(const Position& pos, IndexList& active);
  52
  53 // Get a list of indices for recently changed features
  54 template<Color Perspective>
  55 void HalfKAv2_hm::append_changed_indices(Square            ksq,
  56                                          const DirtyPiece& dp,
  57                                          IndexList&        removed,
  58                                          IndexList&        added) {
  59     for (int i = 0; i < dp.dirty_num; ++i)
  60     {
  61         if (dp.from[i] != SQ_NONE)
  62             removed.push_back(make_index<Perspective>(dp.from[i], dp.piece[i], ksq));
  63         if (dp.to[i] != SQ_NONE)
  64             added.push_back(make_index<Perspective>(dp.to[i], dp.piece[i], ksq));
  65     }
  66 }
  67
  68 // Explicit template instantiations
  69 template void HalfKAv2_hm::append_changed_indices<WHITE>(Square            ksq,
  70                                                          const DirtyPiece& dp,
  71                                                          IndexList&        removed,
  72                                                          IndexList&        added);
  73 template void HalfKAv2_hm::append_changed_indices<BLACK>(Square            ksq,
  74                                                          const DirtyPiece& dp,
  75                                                          IndexList&        removed,
  76                                                          IndexList&        added);
  77
  78 int HalfKAv2_hm::update_cost(const StateInfo* st) { return st->dirtyPiece.dirty_num; }
  79
  80 int HalfKAv2_hm::refresh_cost(const Position& pos) { return pos.count<ALL_PIECES>(); }
  81
  82 bool HalfKAv2_hm::requires_refresh(const StateInfo* st, Color perspective) {
  83     return st->dirtyPiece.piece[0] == make_piece(perspective, KING);
  84 }
  85
  86 }  // namespace Stockfish::Eval::NNUE::Features