X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fendgame.cpp;h=ec54d4e69ea5114265e0d47d05a4fd0cc68f2c4b;hb=7eb6a488ade31254151fd516aa4c94fc56b84a1f;hp=8280131753b859ea1ea784230eb1abde1c23f7d8;hpb=14df99130f53a2a5f57260eb830b4c0029bd4e99;p=stockfish
diff --git a/src/endgame.cpp b/src/endgame.cpp
index 82801317..ec54d4e6 100644
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -1,7 +1,7 @@
/*
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
@@ -17,12 +17,12 @@
along with this program. If not, see .
*/
-#include
#include
+#include
#include "bitcount.h"
#include "endgame.h"
-#include "pawns.h"
+#include "movegen.h"
using std::string;
@@ -60,43 +60,33 @@ namespace {
// 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) {
-
- 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) {
+ // 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) {
- assert(keyCode.length() > 0 && keyCode.length() < 8);
- assert(keyCode[0] == 'K');
+ assert(code.length() > 0 && code.length() < 8);
+ assert(code[0] == 'K');
- string fen;
- size_t i = 0;
+ string sides[] = { code.substr(code.find('K', 1)), // Weaker
+ code.substr(0, code.find('K', 1)) }; // Stronger
- // 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());
+ transform(sides[c].begin(), sides[c].end(), sides[c].begin(), tolower);
- // 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";
+ string fen = sides[0] + char('0' + int(8 - code.length()))
+ + sides[1] + "/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).get_material_key();
+ return Position(fen, false, 0).material_key();
}
-} // namespace
+ template
+ void delete_endgame(const typename M::value_type& p) { delete p.second; }
+} // namespace
-/// Endgames member definitions
-template<> const Endgames::M1& Endgames::map() const { return m1; }
-template<> const Endgames::M2& Endgames::map() const { return m2; }
+/// Endgames members definitions
Endgames::Endgames() {
@@ -119,21 +109,17 @@ Endgames::Endgames() {
Endgames::~Endgames() {
- for (M1::const_iterator it = m1.begin(); it != m1.end(); ++it)
- delete it->second;
-
- for (M2::const_iterator it = m2.begin(); it != m2.end(); ++it)
- delete it->second;
+ for_each(m1.begin(), m1.end(), delete_endgame);
+ for_each(m2.begin(), m2.end(), delete_endgame);
}
template
-void Endgames::add(const string& keyCode) {
+void Endgames::add(const string& code) {
typedef typename eg_family::type T;
- typedef typename Map::type M;
- const_cast(map()).insert(std::make_pair(mat_key(keyCode), new Endgame(WHITE)));
- const_cast(map()).insert(std::make_pair(mat_key(swap_colors(keyCode)), new Endgame(BLACK)));
+ map((T*)0)[key(code, WHITE)] = new Endgame(WHITE);
+ map((T*)0)[key(code, BLACK)] = new Endgame(BLACK);
}
@@ -147,6 +133,13 @@ Value Endgame::operator()(const Position& pos) const {
assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO);
assert(pos.piece_count(weakerSide, PAWN) == VALUE_ZERO);
+ // Stalemate detection with lone king
+ if ( pos.side_to_move() == weakerSide
+ && !pos.in_check()
+ && !MoveList(pos).size()) {
+ return VALUE_DRAW;
+ }
+
Square winnerKSq = pos.king_square(strongerSide);
Square loserKSq = pos.king_square(weakerSide);
@@ -157,9 +150,9 @@ Value Endgame::operator()(const Position& pos) const {
if ( pos.piece_count(strongerSide, QUEEN)
|| pos.piece_count(strongerSide, ROOK)
- || pos.piece_count(strongerSide, BISHOP) > 1)
- // TODO: check for two equal-colored bishops!
- result += VALUE_KNOWN_WIN;
+ || pos.both_color_bishops(strongerSide)) {
+ result += VALUE_KNOWN_WIN;
+ }
return strongerSide == pos.side_to_move() ? result : -result;
}
@@ -219,10 +212,10 @@ Value Endgame::operator()(const Position& pos) const {
}
else
{
- wksq = flip(pos.king_square(BLACK));
- bksq = flip(pos.king_square(WHITE));
- wpsq = flip(pos.piece_list(BLACK, PAWN)[0]);
- stm = flip(pos.side_to_move());
+ wksq = ~pos.king_square(BLACK);
+ bksq = ~pos.king_square(WHITE);
+ wpsq = ~pos.piece_list(BLACK, PAWN)[0];
+ stm = ~pos.side_to_move();
}
if (file_of(wpsq) >= FILE_E)
@@ -265,10 +258,10 @@ Value Endgame::operator()(const Position& pos) const {
if (strongerSide == BLACK)
{
- wksq = flip(wksq);
- wrsq = flip(wrsq);
- bksq = flip(bksq);
- bpsq = flip(bpsq);
+ wksq = ~wksq;
+ wrsq = ~wrsq;
+ bksq = ~bksq;
+ bpsq = ~bpsq;
}
Square queeningSq = make_square(file_of(bpsq), RANK_1);
@@ -383,7 +376,7 @@ Value Endgame::operator()(const Position& pos) const {
result += Value(square_distance(bksq, nsq) * 32);
// Bonus for restricting the knight's mobility
- result += Value((8 - count_1s(pos.attacks_from(nsq))) * 8);
+ result += Value((8 - popcount(pos.attacks_from(nsq))) * 8);
return strongerSide == pos.side_to_move() ? result : -result;
}
@@ -430,7 +423,7 @@ ScaleFactor Endgame::operator()(const Position& pos) const {
&& abs(file_of(kingSq) - pawnFile) <= 1)
{
// The bishop has the wrong color, and the defending king is on the
- // file of the pawn(s) or the neighboring file. Find the rank of the
+ // file of the pawn(s) or the adjacent file. Find the rank of the
// frontmost pawn.
Rank rank;
if (strongerSide == WHITE)
@@ -505,11 +498,11 @@ ScaleFactor Endgame::operator()(const Position& pos) const {
// pawn is on the left half of the board.
if (strongerSide == BLACK)
{
- wksq = flip(wksq);
- wrsq = flip(wrsq);
- wpsq = flip(wpsq);
- bksq = flip(bksq);
- brsq = flip(brsq);
+ wksq = ~wksq;
+ wrsq = ~wrsq;
+ wpsq = ~wpsq;
+ bksq = ~bksq;
+ brsq = ~brsq;
}
if (file_of(wpsq) > FILE_D)
{
@@ -782,7 +775,7 @@ ScaleFactor Endgame::operator()(const Position& pos) const {
return SCALE_FACTOR_NONE;
case 1:
- // Pawns on neighboring files. Draw if defender firmly controls the square
+ // Pawns on adjacent files. Draw if defender firmly controls the square
// in front of the frontmost pawn's path, and the square diagonally behind
// this square on the file of the other pawn.
if ( ksq == blockSq1
@@ -881,10 +874,10 @@ ScaleFactor Endgame::operator()(const Position& pos) const {
if (strongerSide == BLACK)
{
- wksq = flip(wksq);
- bksq = flip(bksq);
- wpsq = flip(wpsq);
- stm = flip(stm);
+ wksq = ~wksq;
+ bksq = ~bksq;
+ wpsq = ~wpsq;
+ stm = ~stm;
}
if (file_of(wpsq) >= FILE_E)