X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fnnue%2Ffeatures%2Fhalf_ka_v2.cpp;fp=src%2Fnnue%2Ffeatures%2Fhalf_ka_v2.cpp;h=57f43e50f2ffdc35ea01f32d6030d8eff90236aa;hb=e8d64af1230fdac65bb0da246df3e7abe82e0838;hp=0000000000000000000000000000000000000000;hpb=f90274d8ce1aad4ad0595aacbceb74b6cbe306a8;p=stockfish

diff --git a/src/nnue/features/half_ka_v2.cpp b/src/nnue/features/half_ka_v2.cpp
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+++ b/src/nnue/features/half_ka_v2.cpp
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+/*
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+
+  Stockfish is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  Stockfish is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+//Definition of input features HalfKAv2 of NNUE evaluation function
+
+#include "half_ka_v2.h"
+
+#include "../../position.h"
+
+namespace Stockfish::Eval::NNUE::Features {
+
+  // Orient a square according to perspective (rotates by 180 for black)
+  inline Square HalfKAv2::orient(Color perspective, Square s) {
+    return Square(int(s) ^ (bool(perspective) * 56));
+  }
+
+  // Index of a feature for a given king position and another piece on some square
+  inline IndexType HalfKAv2::make_index(Color perspective, Square s, Piece pc, Square ksq) {
+    return IndexType(orient(perspective, s) + PieceSquareIndex[perspective][pc] + PS_NB * ksq);
+  }
+
+  // Get a list of indices for active features
+  void HalfKAv2::append_active_indices(
+    const Position& pos,
+    Color perspective,
+    ValueListInserter<IndexType> active
+  ) {
+    Square ksq = orient(perspective, pos.square<KING>(perspective));
+    Bitboard bb = pos.pieces();
+    while (bb)
+    {
+      Square s = pop_lsb(bb);
+      active.push_back(make_index(perspective, s, pos.piece_on(s), ksq));
+    }
+  }
+
+
+  // append_changed_indices() : get a list of indices for recently changed features
+
+  void HalfKAv2::append_changed_indices(
+    Square ksq,
+    StateInfo* st,
+    Color perspective,
+    ValueListInserter<IndexType> removed,
+    ValueListInserter<IndexType> added
+  ) {
+    const auto& dp = st->dirtyPiece;
+    Square oriented_ksq = orient(perspective, ksq);
+    for (int i = 0; i < dp.dirty_num; ++i) {
+      Piece pc = dp.piece[i];
+      if (dp.from[i] != SQ_NONE)
+        removed.push_back(make_index(perspective, dp.from[i], pc, oriented_ksq));
+      if (dp.to[i] != SQ_NONE)
+        added.push_back(make_index(perspective, dp.to[i], pc, oriented_ksq));
+    }
+  }
+
+  int HalfKAv2::update_cost(StateInfo* st) {
+    return st->dirtyPiece.dirty_num;
+  }
+
+  int HalfKAv2::refresh_cost(const Position& pos) {
+    return pos.count<ALL_PIECES>();
+  }
+
+  bool HalfKAv2::requires_refresh(StateInfo* st, Color perspective) {
+    return st->dirtyPiece.piece[0] == make_piece(perspective, KING);
+  }
+
+}  // namespace Stockfish::Eval::NNUE::Features