}
// Evaluate the material balance
-
- const int bishopsPair_count[2] = { pos.piece_count(WHITE, BISHOP) > 1, pos.piece_count(BLACK, BISHOP) > 1 };
+ const int pieceCount[2][6] = { { pos.piece_count(WHITE, BISHOP) > 1, pos.piece_count(WHITE, PAWN), pos.piece_count(WHITE, KNIGHT),
+ pos.piece_count(WHITE, BISHOP), pos.piece_count(WHITE, ROOK), pos.piece_count(WHITE, QUEEN) },
+ { pos.piece_count(BLACK, BISHOP) > 1, pos.piece_count(BLACK, PAWN), pos.piece_count(BLACK, KNIGHT),
+ pos.piece_count(BLACK, BISHOP), pos.piece_count(BLACK, ROOK), pos.piece_count(BLACK, QUEEN) } };
Color c, them;
int sign;
int matValue = 0;
// Redundancy of major pieces, formula based on Kaufman's paper
// "The Evaluation of Material Imbalances in Chess"
// http://mywebpages.comcast.net/danheisman/Articles/evaluation_of_material_imbalance.htm
- if (pos.piece_count(c, ROOK) >= 1)
- matValue -= sign * ((pos.piece_count(c, ROOK) - 1) * RedundantRookPenalty + pos.piece_count(c, QUEEN) * RedundantQueenPenalty);
+ if (pieceCount[c][ROOK] >= 1)
+ matValue -= sign * ((pieceCount[c][ROOK] - 1) * RedundantRookPenalty + pieceCount[c][QUEEN] * RedundantQueenPenalty);
// Second-degree polynomial material imbalance by Tord Romstad
//
// We use NO_PIECE_TYPE as a place holder for the bishop pair "extended piece",
// this allow us to be more flexible in defining bishop pair bonuses.
them = opposite_color(c);
- for (PieceType pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++)
+ for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++)
{
- int c1, c2, c3;
- c1 = sign * (pt1 != NO_PIECE_TYPE ? pos.piece_count(c, pt1) : bishopsPair_count[c]);
+ int c1 = sign * pieceCount[c][pt1];
if (!c1)
continue;
matValue += c1 * LinearCoefficients[pt1];
- for (PieceType pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++)
+ for (int pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++)
{
- c2 = (pt2 != NO_PIECE_TYPE ? pos.piece_count(c, pt2) : bishopsPair_count[c]);
- c3 = (pt2 != NO_PIECE_TYPE ? pos.piece_count(them, pt2) : bishopsPair_count[them]);
- matValue += c1 * c2 * QuadraticCoefficientsSameColor[pt1][pt2];
- matValue += c1 * c3 * QuadraticCoefficientsOppositeColor[pt1][pt2];
+ matValue += c1 * pieceCount[c][pt2] * QuadraticCoefficientsSameColor[pt1][pt2];
+ matValue += c1 * pieceCount[them][pt2] * QuadraticCoefficientsOppositeColor[pt1][pt2];
}
}
}