/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
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 two kings in basic endgames.
const int DistanceBonus[8] = { 0, 0, 100, 80, 60, 40, 20, 10 };
- // Build corresponding key code for the opposite color: "KBPKN" -> "KNKBP"
- const string swap_colors(const string& keyCode) {
+ // Get the material key of a Position out of the given endgame key code
+ // like "KBPKN". The trick here is to first forge an ad-hoc fen string
+ // and then let a Position object to do the work for us. Note that the
+ // fen string could correspond to an illegal position.
+ Key key(const string& code, Color c) {
- size_t idx = keyCode.find('K', 1);
- return keyCode.substr(idx) + keyCode.substr(0, idx);
- }
-
- // Get the material key of a position out of the given endgame key code
- // like "KBPKN". The trick here is to first build up a FEN string and then
- // let a Position object to do the work for us. Note that the FEN string
- // could correspond to an illegal position.
- Key mat_key(const string& keyCode) {
+ assert(code.length() > 0 && code.length() < 8);
+ assert(code[0] == 'K');
- assert(keyCode.length() > 0 && keyCode.length() < 8);
- assert(keyCode[0] == 'K');
+ string sides[] = { code.substr(code.find('K', 1)), // Weaker
+ code.substr(0, code.find('K', 1)) }; // Stronger
- string fen;
- size_t i = 0;
+ transform(sides[c].begin(), sides[c].end(), sides[c].begin(), tolower);
- // First add white and then black pieces
- do fen += keyCode[i]; while (keyCode[++i] != 'K');
- do fen += char(tolower(keyCode[i])); while (++i < keyCode.length());
+ string fen = sides[0] + char('0' + int(8 - code.length()))
+ + sides[1] + "/8/8/8/8/8/8/8 w - - 0 10";
- // Add file padding and remaining empty ranks
- fen += string(1, '0' + int(8 - keyCode.length())) + "/8/8/8/8/8/8/8 w - - 0 10";
-
- // Build a Position out of the fen string and get its material key
return Position(fen, false, 0).material_key();
}
} // namespace
-/// Endgames member definitions
-
-template<> const Endgames::M1& Endgames::map<Endgames::M1>() const { return m1; }
-template<> const Endgames::M2& Endgames::map<Endgames::M2>() const { return m2; }
+/// Endgames members definitions
Endgames::Endgames() {
}
template<EndgameType E>
-void Endgames::add(const string& keyCode) {
+void Endgames::add(const string& code) {
typedef typename eg_family<E>::type T;
- typedef typename Map<T>::type M;
- const_cast<M&>(map<M>()).insert(std::make_pair(mat_key(keyCode), new Endgame<E>(WHITE)));
- const_cast<M&>(map<M>()).insert(std::make_pair(mat_key(swap_colors(keyCode)), new Endgame<E>(BLACK)));
+ map((T*)0)[key(code, WHITE)] = new Endgame<E>(WHITE);
+ map((T*)0)[key(code, BLACK)] = new Endgame<E>(BLACK);
}
result += Value(square_distance(bksq, nsq) * 32);
// Bonus for restricting the knight's mobility
- result += Value((8 - count_1s<CNT32_MAX15>(pos.attacks_from<KNIGHT>(nsq))) * 8);
+ result += Value((8 - popcount<Max15>(pos.attacks_from<KNIGHT>(nsq))) * 8);
return strongerSide == pos.side_to_move() ? result : -result;
}