/*
- Glaurung, a UCI chess playing engine.
- Copyright (C) 2004-2008 Tord Romstad
+ Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+ Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+ Copyright (C) 2008 Marco Costalba
- Glaurung is free software: you can redistribute it and/or modify
+ 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.
-
- Glaurung is distributed in the hope that it will be useful,
+
+ 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/>.
*/
////
#include <cassert>
+#include <map>
#include "material.h"
const Value BishopPairMidgameBonus = Value(100);
const Value BishopPairEndgameBonus = Value(100);
- Key KPKMaterialKey, KKPMaterialKey;
- Key KBNKMaterialKey, KKBNMaterialKey;
- Key KRKPMaterialKey, KPKRMaterialKey;
- Key KRKBMaterialKey, KBKRMaterialKey;
- Key KRKNMaterialKey, KNKRMaterialKey;
- Key KQKRMaterialKey, KRKQMaterialKey;
Key KRPKRMaterialKey, KRKRPMaterialKey;
- Key KRPPKRPMaterialKey, KRPKRPPMaterialKey;
- Key KNNKMaterialKey, KKNNMaterialKey;
+ Key KNNKMaterialKey, KKNNMaterialKey;
Key KBPKBMaterialKey, KBKBPMaterialKey;
Key KBPKNMaterialKey, KNKBPMaterialKey;
- Key KNPKMaterialKey, KKNPMaterialKey;
+ Key KNPKMaterialKey, KKNPMaterialKey;
Key KPKPMaterialKey;
+ Key KRPPKRPMaterialKey, KRPKRPPMaterialKey;
-};
+ std::map<Key, EndgameEvaluationFunction*> EEFmap;
+
+ void EEFAdd(Key k, EndgameEvaluationFunction* f) {
+
+ EEFmap.insert(std::pair<Key, EndgameEvaluationFunction*>(k, f));
+ }
+}
////
//// Functions
////
-/// MaterialInfo::init() is called during program initialization. It
+/// MaterialInfo::init() is called during program initialization. It
/// precomputes material hash keys for a few basic endgames, in order
/// to make it easy to recognize such endgames when they occur.
void MaterialInfo::init() {
- KPKMaterialKey = Position::zobMaterial[WHITE][PAWN][1];
- KKPMaterialKey = Position::zobMaterial[BLACK][PAWN][1];
- KBNKMaterialKey =
- Position::zobMaterial[WHITE][BISHOP][1] ^
- Position::zobMaterial[WHITE][KNIGHT][1];
- KKBNMaterialKey =
- Position::zobMaterial[BLACK][BISHOP][1] ^
- Position::zobMaterial[BLACK][KNIGHT][1];
- KRKPMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[BLACK][PAWN][1];
- KPKRMaterialKey =
- Position::zobMaterial[WHITE][PAWN][1] ^
- Position::zobMaterial[BLACK][ROOK][1];
- KRKBMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[BLACK][BISHOP][1];
- KBKRMaterialKey =
- Position::zobMaterial[WHITE][BISHOP][1] ^
- Position::zobMaterial[BLACK][ROOK][1];
- KRKNMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[BLACK][KNIGHT][1];
- KNKRMaterialKey =
- Position::zobMaterial[WHITE][KNIGHT][1] ^
- Position::zobMaterial[BLACK][ROOK][1];
- KQKRMaterialKey =
- Position::zobMaterial[WHITE][QUEEN][1] ^
- Position::zobMaterial[BLACK][ROOK][1];
- KRKQMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[BLACK][QUEEN][1];
- KRPKRMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[WHITE][PAWN][1] ^
- Position::zobMaterial[BLACK][ROOK][1];
- KRKRPMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[BLACK][ROOK][1] ^
- Position::zobMaterial[BLACK][PAWN][1];
+
+ typedef Key ZM[2][8][16];
+ const ZM& z = Position::zobMaterial;
+
+ static const Color W = WHITE;
+ static const Color B = BLACK;
+
+ EEFAdd(z[W][PAWN][1], &EvaluateKPK);
+ EEFAdd(z[B][PAWN][1], &EvaluateKKP);
+
+ EEFAdd(z[W][BISHOP][1] ^ z[W][KNIGHT][1], &EvaluateKBNK);
+ EEFAdd(z[B][BISHOP][1] ^ z[B][KNIGHT][1], &EvaluateKKBN);
+ EEFAdd(z[W][ROOK][1] ^ z[B][PAWN][1], &EvaluateKRKP);
+ EEFAdd(z[W][PAWN][1] ^ z[B][ROOK][1], &EvaluateKPKR);
+ EEFAdd(z[W][ROOK][1] ^ z[B][BISHOP][1], &EvaluateKRKB);
+ EEFAdd(z[W][BISHOP][1] ^ z[B][ROOK][1], &EvaluateKBKR);
+ EEFAdd(z[W][ROOK][1] ^ z[B][KNIGHT][1], &EvaluateKRKN);
+ EEFAdd(z[W][KNIGHT][1] ^ z[B][ROOK][1], &EvaluateKNKR);
+ EEFAdd(z[W][QUEEN][1] ^ z[B][ROOK][1], &EvaluateKQKR);
+ EEFAdd(z[W][ROOK][1] ^ z[B][QUEEN][1], &EvaluateKRKQ);
+
+ KRPKRMaterialKey = z[W][ROOK][1]
+ ^ z[W][PAWN][1]
+ ^ z[B][ROOK][1];
+
+ KRKRPMaterialKey = z[W][ROOK][1]
+ ^ z[B][ROOK][1]
+ ^ z[B][PAWN][1];
+
KRPPKRPMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[WHITE][PAWN][1] ^
- Position::zobMaterial[WHITE][PAWN][2] ^
- Position::zobMaterial[BLACK][ROOK][1] ^
- Position::zobMaterial[BLACK][PAWN][1];
+ z[W][ROOK][1] ^
+ z[W][PAWN][1] ^
+ z[W][PAWN][2] ^
+ z[B][ROOK][1] ^
+ z[B][PAWN][1];
KRPKRPPMaterialKey =
- Position::zobMaterial[WHITE][ROOK][1] ^
- Position::zobMaterial[WHITE][PAWN][1] ^
- Position::zobMaterial[BLACK][ROOK][1] ^
- Position::zobMaterial[BLACK][PAWN][1] ^
- Position::zobMaterial[BLACK][PAWN][2];
+ z[W][ROOK][1] ^
+ z[W][PAWN][1] ^
+ z[B][ROOK][1] ^
+ z[B][PAWN][1] ^
+ z[B][PAWN][2];
KNNKMaterialKey =
- Position::zobMaterial[WHITE][KNIGHT][1] ^
- Position::zobMaterial[WHITE][KNIGHT][2];
+ z[W][KNIGHT][1] ^
+ z[W][KNIGHT][2];
KKNNMaterialKey =
- Position::zobMaterial[BLACK][KNIGHT][1] ^
- Position::zobMaterial[BLACK][KNIGHT][2];
+ z[B][KNIGHT][1] ^
+ z[B][KNIGHT][2];
KBPKBMaterialKey =
- Position::zobMaterial[WHITE][BISHOP][1] ^
- Position::zobMaterial[WHITE][PAWN][1] ^
- Position::zobMaterial[BLACK][BISHOP][1];
+ z[W][BISHOP][1] ^
+ z[W][PAWN][1] ^
+ z[B][BISHOP][1];
KBKBPMaterialKey =
- Position::zobMaterial[WHITE][BISHOP][1] ^
- Position::zobMaterial[BLACK][BISHOP][1] ^
- Position::zobMaterial[BLACK][PAWN][1];
+ z[W][BISHOP][1] ^
+ z[B][BISHOP][1] ^
+ z[B][PAWN][1];
KBPKNMaterialKey =
- Position::zobMaterial[WHITE][BISHOP][1] ^
- Position::zobMaterial[WHITE][PAWN][1] ^
- Position::zobMaterial[BLACK][KNIGHT][1];
+ z[W][BISHOP][1] ^
+ z[W][PAWN][1] ^
+ z[B][KNIGHT][1];
KNKBPMaterialKey =
- Position::zobMaterial[WHITE][KNIGHT][1] ^
- Position::zobMaterial[BLACK][BISHOP][1] ^
- Position::zobMaterial[BLACK][PAWN][1];
+ z[W][KNIGHT][1] ^
+ z[B][BISHOP][1] ^
+ z[B][PAWN][1];
KNPKMaterialKey =
- Position::zobMaterial[WHITE][KNIGHT][1] ^
- Position::zobMaterial[WHITE][PAWN][1];
+ z[W][KNIGHT][1] ^
+ z[W][PAWN][1];
KKNPMaterialKey =
- Position::zobMaterial[BLACK][KNIGHT][1] ^
- Position::zobMaterial[BLACK][PAWN][1];
+ z[B][KNIGHT][1] ^
+ z[B][PAWN][1];
KPKPMaterialKey =
- Position::zobMaterial[WHITE][PAWN][1] ^
- Position::zobMaterial[BLACK][PAWN][1];
+ z[W][PAWN][1] ^
+ z[B][PAWN][1];
+
+
}
/// Constructor for the MaterialInfoTable class.
MaterialInfoTable::MaterialInfoTable(unsigned numOfEntries) {
+
size = numOfEntries;
entries = new MaterialInfo[size];
- if(entries == NULL) {
- std::cerr << "Failed to allocate " << (numOfEntries * sizeof(MaterialInfo))
- << " bytes for material hash table." << std::endl;
- exit(EXIT_FAILURE);
+ if (!entries)
+ {
+ std::cerr << "Failed to allocate " << (numOfEntries * sizeof(MaterialInfo))
+ << " bytes for material hash table." << std::endl;
+ exit(EXIT_FAILURE);
}
- this->clear();
+ clear();
}
/// Destructor for the MaterialInfoTable class.
MaterialInfoTable::~MaterialInfoTable() {
+
delete [] entries;
}
/// all entries to 0.
void MaterialInfoTable::clear() {
+
memset(entries, 0, size * sizeof(MaterialInfo));
}
/// MaterialInfoTable::get_material_info() takes a position object as input,
/// computes or looks up a MaterialInfo object, and returns a pointer to it.
/// If the material configuration is not already present in the table, it
-/// is stored there, so we don't have to recompute everything when the
+/// is stored there, so we don't have to recompute everything when the
/// same material configuration occurs again.
MaterialInfo *MaterialInfoTable::get_material_info(const Position &pos) {
+
Key key = pos.get_material_key();
int index = key & (size - 1);
MaterialInfo *mi = entries + index;
- // If mi->key matches the position's material hash key, it means that we
+ // If mi->key matches the position's material hash key, it means that we
// have analysed this material configuration before, and we can simply
// return the information we found the last time instead of recomputing it:
if(mi->key == key)
// A special case before looking for a specialized evaluation function:
// KNN vs K is a draw:
- if(key == KNNKMaterialKey || key == KKNNMaterialKey) {
+ if (key == KNNKMaterialKey || key == KKNNMaterialKey)
+ {
mi->factor[WHITE] = mi->factor[BLACK] = 0;
return mi;
}
// Let's look if we have a specialized evaluation function for this
- // particular material configuration:
- if(key == KPKMaterialKey) {
- mi->evaluationFunction = &EvaluateKPK;
- return mi;
- }
- else if(key == KKPMaterialKey) {
- mi->evaluationFunction = &EvaluateKKP;
- return mi;
+ // particular material configuration
+ if (EEFmap.find(key) != EEFmap.end())
+ {
+ mi->evaluationFunction = EEFmap[key];
+ return mi;
}
- else if(key == KBNKMaterialKey) {
- mi->evaluationFunction = &EvaluateKBNK;
- return mi;
+ else if ( pos.non_pawn_material(BLACK) == Value(0)
+ && pos.piece_count(BLACK, PAWN) == 0
+ && pos.non_pawn_material(WHITE) >= RookValueEndgame)
+ {
+ mi->evaluationFunction = &EvaluateKXK;
+ return mi;
}
- else if(key == KKBNMaterialKey) {
- mi->evaluationFunction = &EvaluateKKBN;
- return mi;
- }
- else if(key == KRKPMaterialKey) {
- mi->evaluationFunction = &EvaluateKRKP;
- return mi;
- }
- else if(key == KPKRMaterialKey) {
- mi->evaluationFunction = &EvaluateKPKR;
- return mi;
- }
- else if(key == KRKBMaterialKey) {
- mi->evaluationFunction = &EvaluateKRKB;
- return mi;
- }
- else if(key == KBKRMaterialKey) {
- mi->evaluationFunction = &EvaluateKBKR;
- return mi;
- }
- else if(key == KRKNMaterialKey) {
- mi->evaluationFunction = &EvaluateKRKN;
- return mi;
- }
- else if(key == KNKRMaterialKey) {
- mi->evaluationFunction = &EvaluateKNKR;
- return mi;
- }
- else if(key == KQKRMaterialKey) {
- mi->evaluationFunction = &EvaluateKQKR;
- return mi;
- }
- else if(key == KRKQMaterialKey) {
- mi->evaluationFunction = &EvaluateKRKQ;
- return mi;
- }
- else if(pos.non_pawn_material(BLACK) == Value(0) &&
- pos.pawn_count(BLACK) == 0 &&
- pos.non_pawn_material(WHITE) >= RookValueEndgame) {
- mi->evaluationFunction = &EvaluateKXK;
- return mi;
- }
- else if(pos.non_pawn_material(WHITE) == Value(0) &&
- pos.pawn_count(WHITE) == 0 &&
- pos.non_pawn_material(BLACK) >= RookValueEndgame) {
- mi->evaluationFunction = &EvaluateKKX;
- return mi;
+ else if ( pos.non_pawn_material(WHITE) == Value(0)
+ && pos.piece_count(WHITE, PAWN) == 0
+ && pos.non_pawn_material(BLACK) >= RookValueEndgame)
+ {
+ mi->evaluationFunction = &EvaluateKKX;
+ return mi;
}
// OK, we didn't find any special evaluation function for the current
- // material configuration. Is there a suitable scaling function?
+ // material configuration. Is there a suitable scaling function?
//
// The code below is rather messy, and it could easily get worse later,
// if we decide to add more special cases. We face problems when there
}
if(pos.non_pawn_material(WHITE) == BishopValueMidgame &&
- pos.bishop_count(WHITE) == 1 && pos.pawn_count(WHITE) >= 1)
+ pos.piece_count(WHITE, BISHOP) == 1 && pos.piece_count(WHITE, PAWN) >= 1)
mi->scalingFunction[WHITE] = &ScaleKBPK;
if(pos.non_pawn_material(BLACK) == BishopValueMidgame &&
- pos.bishop_count(BLACK) == 1 && pos.pawn_count(BLACK) >= 1)
+ pos.piece_count(BLACK, BISHOP) == 1 && pos.piece_count(BLACK, PAWN) >= 1)
mi->scalingFunction[BLACK] = &ScaleKKBP;
- if(pos.pawn_count(WHITE) == 0 &&
+ if(pos.piece_count(WHITE, PAWN) == 0 &&
pos.non_pawn_material(WHITE) == QueenValueMidgame &&
- pos.queen_count(WHITE) == 1 &&
- pos.rook_count(BLACK) == 1 && pos.pawn_count(BLACK) >= 1)
+ pos.piece_count(WHITE, QUEEN) == 1 &&
+ pos.piece_count(BLACK, ROOK) == 1 && pos.piece_count(BLACK, PAWN) >= 1)
mi->scalingFunction[WHITE] = &ScaleKQKRP;
- else if(pos.pawn_count(BLACK) == 0 &&
+ else if(pos.piece_count(BLACK, PAWN) == 0 &&
pos.non_pawn_material(BLACK) == QueenValueMidgame &&
- pos.queen_count(BLACK) == 1 &&
- pos.rook_count(WHITE) == 1 && pos.pawn_count(WHITE) >= 1)
+ pos.piece_count(BLACK, QUEEN) == 1 &&
+ pos.piece_count(WHITE, ROOK) == 1 && pos.piece_count(WHITE, PAWN) >= 1)
mi->scalingFunction[BLACK] = &ScaleKRPKQ;
if(pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) == Value(0)) {
- if(pos.pawn_count(BLACK) == 0) {
- assert(pos.pawn_count(WHITE) >= 2);
+ if(pos.piece_count(BLACK, PAWN) == 0) {
+ assert(pos.piece_count(WHITE, PAWN) >= 2);
mi->scalingFunction[WHITE] = &ScaleKPsK;
}
- else if(pos.pawn_count(WHITE) == 0) {
- assert(pos.pawn_count(BLACK) >= 2);
+ else if(pos.piece_count(WHITE, PAWN) == 0) {
+ assert(pos.piece_count(BLACK, PAWN) >= 2);
mi->scalingFunction[BLACK] = &ScaleKKPs;
}
- else if(pos.pawn_count(WHITE) == 1 && pos.pawn_count(BLACK) == 1) {
+ else if(pos.piece_count(WHITE, PAWN) == 1 && pos.piece_count(BLACK, PAWN) == 1) {
mi->scalingFunction[WHITE] = &ScaleKPKPw;
mi->scalingFunction[BLACK] = &ScaleKPKPb;
}
}
// Evaluate the material balance.
-
+
Color c;
int sign;
Value egValue = Value(0), mgValue = Value(0);
-
+
for(c = WHITE, sign = 1; c <= BLACK; c++, sign = -sign) {
// No pawns makes it difficult to win, even with a material advantage:
- if(pos.pawn_count(c) == 0 &&
+ if(pos.piece_count(c, PAWN) == 0 &&
pos.non_pawn_material(c) - pos.non_pawn_material(opposite_color(c))
<= BishopValueMidgame) {
if(pos.non_pawn_material(c) == pos.non_pawn_material(opposite_color(c)))
else if(pos.non_pawn_material(c) < RookValueMidgame)
mi->factor[c] = 0;
else {
- switch(pos.bishop_count(c)) {
+ switch(pos.piece_count(c, BISHOP)) {
case 2:
mi->factor[c] = 32; break;
case 1:
}
}
}
-
+
// Bishop pair:
- if(pos.bishop_count(c) >= 2) {
+ if(pos.piece_count(c, BISHOP) >= 2) {
mgValue += sign * BishopPairMidgameBonus;
egValue += sign * BishopPairEndgameBonus;
}
- // Knights are stronger when there are many pawns on the board. The
+ // Knights are stronger when there are many pawns on the board. The
// formula is taken from Larry Kaufman's paper "The Evaluation of Material
- // Imbalances in Chess":
+ // Imbalances in Chess":
// http://mywebpages.comcast.net/danheisman/Articles/evaluation_of_material_imbalance.htm
- mgValue += sign * Value(pos.knight_count(c)*(pos.pawn_count(c)-5)*16);
- egValue += sign * Value(pos.knight_count(c)*(pos.pawn_count(c)-5)*16);
+ mgValue += sign * Value(pos.piece_count(c, KNIGHT)*(pos.piece_count(c, PAWN)-5)*16);
+ egValue += sign * Value(pos.piece_count(c, KNIGHT)*(pos.piece_count(c, PAWN)-5)*16);
// Redundancy of major pieces, again based on Kaufman's paper:
- if(pos.rook_count(c) >= 1) {
- Value v = Value((pos.rook_count(c) - 1) * 32 + pos.queen_count(c) * 16);
+ if(pos.piece_count(c, ROOK) >= 1) {
+ Value v = Value((pos.piece_count(c, ROOK) - 1) * 32 + pos.piece_count(c, QUEEN) * 16);
mgValue -= sign * v;
egValue -= sign * v;
}
-
+
}
mi->mgValue = int16_t(mgValue);