本文整理汇总了C#中Position.empty方法的典型用法代码示例。如果您正苦于以下问题:C# Position.empty方法的具体用法?C# Position.empty怎么用?C# Position.empty使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类Position
的用法示例。
在下文中一共展示了Position.empty方法的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: evaluate_passed_pawns
// evaluate_passed_pawns() evaluates the passed pawns of the given color
private static ScoreT evaluate_passed_pawns(ColorT Us, bool DoTrace, Position pos, EvalInfo ei)
{
var Them = (Us == Color.WHITE ? Color.BLACK : Color.WHITE);
var score = Score.SCORE_ZERO;
var b = ei.pi.passed_pawns(Us);
while (b!=0)
{
var s = Utils.pop_lsb(ref b);
Debug.Assert(pos.pawn_passed(Us, s));
int r = Rank.relative_rank_CtSt(Us, s) - Rank.RANK_2;
var rr = r*(r - 1);
ValueT mbonus = Passed[(int) Phase.MG][r], ebonus = Passed[(int) Phase.EG][r];
if (rr != 0)
{
var blockSq = s + Square.pawn_push(Us);
// Adjust bonus based on the king's proximity
ebonus += Utils.distance_Square(pos.square(PieceType.KING, Them), blockSq)*5*rr
- Utils.distance_Square(pos.square(PieceType.KING, Us), blockSq)*2*rr;
// If blockSq is not the queening square then consider also a second push
if (Rank.relative_rank_CtSt(Us, blockSq) != Rank.RANK_8)
{
ebonus -= Utils.distance_Square(pos.square(PieceType.KING, Us), blockSq + Square.pawn_push(Us))*rr;
}
// If the pawn is free to advance, then increase the bonus
if (pos.empty(blockSq))
{
// If there is a rook or queen attacking/defending the pawn from behind,
// consider all the squaresToQueen. Otherwise consider only the squares
// in the pawn's path attacked or occupied by the enemy.
BitboardT squaresToQueen;
BitboardT unsafeSquares;
var defendedSquares = unsafeSquares = squaresToQueen = Utils.forward_bb(Us, s);
var bb = Utils.forward_bb(Them, s) & pos.pieces_PtPt(PieceType.ROOK, PieceType.QUEEN)
& pos.attacks_from_PtS(PieceType.ROOK, s);
if ((pos.pieces_Ct(Us) & bb)==0)
{
defendedSquares &= ei.attackedBy[Us, PieceType.ALL_PIECES];
}
if ((pos.pieces_Ct(Them) & bb) == 0)
{
unsafeSquares &= ei.attackedBy[Them, PieceType.ALL_PIECES] | pos.pieces_Ct(Them);
}
// If there aren't any enemy attacks, assign a big bonus. Otherwise
// assign a smaller bonus if the block square isn't attacked.
var k = unsafeSquares == 0 ? 18 : Bitboard.AndWithSquare(unsafeSquares, blockSq)==0 ? 8 : 0;
// If the path to queen is fully defended, assign a big bonus.
// Otherwise assign a smaller bonus if the block square is defended.
if (defendedSquares == squaresToQueen)
{
k += 6;
}
else if (Bitboard.AndWithSquare(defendedSquares, blockSq)!=0)
{
k += 4;
}
mbonus += k*rr;
ebonus += k*rr;
}
else if (Bitboard.AndWithSquare(pos.pieces_Ct(Us), blockSq)!=0)
{
mbonus += rr*3 + r*2 + 3;
ebonus += rr + r*2;
}
} // rr != 0
if (pos.count(PieceType.PAWN, Us) < pos.count(PieceType.PAWN, Them))
{
ebonus += ebonus/4;
}
score += Score.make_score(mbonus, ebonus) + PassedFile[Square.file_of(s)];
}
if (DoTrace)
{
add_IdxCtSt((int) Term.PASSED, Us, Score.Multiply(score, Weights[PassedPawns]));
}
// Add the scores to the middlegame and endgame eval
return Score.Multiply(score, Weights[PassedPawns]);
}
示例2: evaluate_pieces
//.........这里部分代码省略.........
var bb = b & ei.attackedBy[Them, PieceType.KING];
if (bb!=0)
{
ei.kingAdjacentZoneAttacksCount[Us] += Bitcount.popcount_Max15(bb);
}
}
if (Pt == PieceType.QUEEN)
{
b &=
~(ei.attackedBy[Them, PieceType.KNIGHT] | ei.attackedBy[Them, PieceType.BISHOP]
| ei.attackedBy[Them, PieceType.ROOK]);
}
var mob = Pt == PieceType.QUEEN
? Bitcount.popcount_Full(b & mobilityArea[Us])
: Bitcount.popcount_Max15(b & mobilityArea[Us]);
mobility[Us] += MobilityBonus[Pt][mob];
if (Pt == PieceType.BISHOP || Pt == PieceType.KNIGHT)
{
// Bonus for outpost square
if (Rank.relative_rank_CtSt(Us, s) >= Rank.RANK_4 && Rank.relative_rank_CtSt(Us, s) <= Rank.RANK_6
&& (pos.pieces_CtPt(Them, PieceType.PAWN) & Utils.pawn_attack_span(Us, s))==0)
{
score +=
Outpost[Pt == PieceType.BISHOP ? 1 : 0][Bitboard.AndWithSquare(ei.attackedBy[Us, PieceType.PAWN], s)!=0 ? 1 : 0];
}
// Bonus when behind a pawn
if (Rank.relative_rank_CtSt(Us, s) < Rank.RANK_5 && Bitboard.AndWithSquare(pos.pieces_Pt(PieceType.PAWN), (s + Square.pawn_push(Us)))!=0)
{
score += MinorBehindPawn;
}
// Penalty for pawns on same color square of bishop
if (Pt == PieceType.BISHOP)
{
score -= BishopPawns*ei.pi.pawns_on_same_color_squares(Us, s);
}
// An important Chess960 pattern: A cornered bishop blocked by a friendly
// pawn diagonally in front of it is a very serious problem, especially
// when that pawn is also blocked.
if (Pt == PieceType.BISHOP && pos.is_chess960()
&& (s == Square.relative_square(Us, Square.SQ_A1) || s == Square.relative_square(Us, Square.SQ_H1)))
{
var d = Square.pawn_push(Us) + (Square.file_of(s) == File.FILE_A ? Square.DELTA_E : Square.DELTA_W);
if (pos.piece_on(s + d) == Piece.make_piece(Us, PieceType.PAWN))
{
score -= !pos.empty(s + d + Square.pawn_push(Us))
? TrappedBishopA1H1*4
: pos.piece_on(s + d + d) == Piece.make_piece(Us, PieceType.PAWN)
? TrappedBishopA1H1*2
: TrappedBishopA1H1;
}
}
}
if (Pt == PieceType.ROOK)
{
// Bonus for aligning with enemy pawns on the same rank/file
if (Rank.relative_rank_CtSt(Us, s) >= Rank.RANK_5)
{
var alignedPawns = pos.pieces_CtPt(Them, PieceType.PAWN) & Utils.PseudoAttacks[PieceType.ROOK, s];
if (alignedPawns!=0)
{
score += Bitcount.popcount_Max15(alignedPawns)*RookOnPawn;
}
}
// Bonus when on an open or semi-open file
if (ei.pi.semiopen_file(Us, Square.file_of(s)) != 0)
{
score += ei.pi.semiopen_file(Them, Square.file_of(s)) != 0 ? RookOnOpenFile : RookOnSemiOpenFile;
}
// Penalize when trapped by the king, even more if king cannot castle
if (mob <= 3 && 0 == ei.pi.semiopen_file(Us, Square.file_of(s)))
{
var ksq = pos.square(PieceType.KING, Us);
if (((Square.file_of(ksq) < File.FILE_E) == (Square.file_of(s) < Square.file_of(ksq)))
&& (Square.rank_of(ksq) == Square.rank_of(s) || Rank.relative_rank_CtSt(Us, ksq) == Rank.RANK_1)
&& 0 == ei.pi.semiopen_side(Us, Square.file_of(ksq), Square.file_of(s) < Square.file_of(ksq)))
{
score -= (TrappedRook - Score.make_score(mob*22, 0))*(1 + (pos.can_castle(Us) == 0 ? 1 : 0));
}
}
}
}
if (DoTrace)
{
add_IdxCtSt(Pt, Us, score);
}
// Recursively call evaluate_pieces() of next piece type until KING excluded
return score - evaluate_pieces(NextPt, Them, DoTrace, pos, ei, mobility, mobilityArea);
}