- mi->mgValue = int16_t(mgValue);
- mi->egValue = int16_t(egValue);
- return mi;
-}
-
-
-/// EndgameFunctions members definition. This helper class is used to
-/// store the maps of end game and scaling functions that MaterialInfoTable
-/// will query for each key. The maps are constant, and are populated only
-/// at construction. Being per thread avoids to use locks to access them.
-
-EndgameFunctions::EndgameFunctions() {
-
- typedef Key ZM[2][8][16];
- const ZM& z = Position::zobMaterial;
-
- static const Color W = WHITE;
- static const Color B = BLACK;
-
- KNNKMaterialKey = z[W][KNIGHT][1] ^ z[W][KNIGHT][2];
- KKNNMaterialKey = z[B][KNIGHT][1] ^ z[B][KNIGHT][2];
-
- add(z[W][PAWN][1], &EvaluateKPK);
- add(z[B][PAWN][1], &EvaluateKKP);
-
- add(z[W][BISHOP][1] ^ z[W][KNIGHT][1], &EvaluateKBNK);
- add(z[B][BISHOP][1] ^ z[B][KNIGHT][1], &EvaluateKKBN);
- add(z[W][ROOK][1] ^ z[B][PAWN][1], &EvaluateKRKP);
- add(z[W][PAWN][1] ^ z[B][ROOK][1], &EvaluateKPKR);
- add(z[W][ROOK][1] ^ z[B][BISHOP][1], &EvaluateKRKB);
- add(z[W][BISHOP][1] ^ z[B][ROOK][1], &EvaluateKBKR);
- add(z[W][ROOK][1] ^ z[B][KNIGHT][1], &EvaluateKRKN);
- add(z[W][KNIGHT][1] ^ z[B][ROOK][1], &EvaluateKNKR);
- add(z[W][QUEEN][1] ^ z[B][ROOK][1], &EvaluateKQKR);
- add(z[W][ROOK][1] ^ z[B][QUEEN][1], &EvaluateKRKQ);
-
- add(z[W][KNIGHT][1] ^ z[W][PAWN][1], W, &ScaleKNPK);
- add(z[B][KNIGHT][1] ^ z[B][PAWN][1], B, &ScaleKKNP);
-
- add(z[W][ROOK][1] ^ z[W][PAWN][1] ^ z[B][ROOK][1] , W, &ScaleKRPKR);
- add(z[W][ROOK][1] ^ z[B][ROOK][1] ^ z[B][PAWN][1] , B, &ScaleKRKRP);
- add(z[W][BISHOP][1] ^ z[W][PAWN][1] ^ z[B][BISHOP][1], W, &ScaleKBPKB);
- add(z[W][BISHOP][1] ^ z[B][BISHOP][1] ^ z[B][PAWN][1] , B, &ScaleKBKBP);
- add(z[W][BISHOP][1] ^ z[W][PAWN][1] ^ z[B][KNIGHT][1], W, &ScaleKBPKN);
- add(z[W][KNIGHT][1] ^ z[B][BISHOP][1] ^ z[B][PAWN][1] , B, &ScaleKNKBP);
-
- add(z[W][ROOK][1] ^ z[W][PAWN][1] ^ z[W][PAWN][2] ^ z[B][ROOK][1] ^ z[B][PAWN][1], W, &ScaleKRPPKRP);
- add(z[W][ROOK][1] ^ z[W][PAWN][1] ^ z[B][ROOK][1] ^ z[B][PAWN][1] ^ z[B][PAWN][2], B, &ScaleKRPKRPP);
-}
-
-void EndgameFunctions::add(Key k, EndgameEvaluationFunction* f) {
-
- EEFmap.insert(std::pair<Key, EndgameEvaluationFunction*>(k, f));
+ // Evaluate the material imbalance. We use PIECE_TYPE_NONE as a place holder
+ // for the bishop pair "extended piece", which allows us to be more flexible
+ // in defining bishop pair bonuses.
+ const int pieceCount[COLOR_NB][PIECE_TYPE_NB] = {
+ { pos.count<BISHOP>(WHITE) > 1, pos.count<PAWN>(WHITE), pos.count<KNIGHT>(WHITE),
+ pos.count<BISHOP>(WHITE) , pos.count<ROOK>(WHITE), pos.count<QUEEN >(WHITE) },
+ { pos.count<BISHOP>(BLACK) > 1, pos.count<PAWN>(BLACK), pos.count<KNIGHT>(BLACK),
+ pos.count<BISHOP>(BLACK) , pos.count<ROOK>(BLACK), pos.count<QUEEN >(BLACK) } };
+
+ e->value = (int16_t)((imbalance<WHITE>(pieceCount) - imbalance<BLACK>(pieceCount)) / 16);
+ return e;