/**
* Generate and return a list of pseudo-legal moves.
* Pseudo-legal means that the moves doesn't necessarily defend from check threats.
*/
public MoveList pseudoLegalMoves(Position pos)
{
MoveList moveList = getMoveListObj();
ulong occupied = pos.whiteBB | pos.blackBB;
if (pos.whiteMove) {
int sq = 0;
ulong m = 0;
// Queen moves
ulong squares = pos.pieceTypeBB[Piece.WQUEEN];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = (BitBoard.rookAttacks(sq, occupied) | BitBoard.bishopAttacks(sq, occupied)) & ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Rook moves
squares = pos.pieceTypeBB[Piece.WROOK];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.rookAttacks(sq, occupied) & ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Bishop moves
squares = pos.pieceTypeBB[Piece.WBISHOP];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.bishopAttacks(sq, occupied) & ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// King moves
{
sq = pos.getKingSq(true);
m = BitBoard.kingAttacks[sq] & ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
int k0 = 4;
if (sq == k0) {
ulong OO_SQ = 0x60L;
ulong OOO_SQ = 0xEL;
if (((pos.getCastleMask() & (1 << Position.H1_CASTLE)) != 0) &&
((OO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 + 3) == Piece.WROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 + 1)) {
setMove(moveList, k0, k0 + 2, Piece.EMPTY);
}
if (((pos.getCastleMask() & (1 << Position.A1_CASTLE)) != 0) &&
((OOO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 - 4) == Piece.WROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 - 1)) {
setMove(moveList, k0, k0 - 2, Piece.EMPTY);
}
}
}
// Knight moves
ulong knights = pos.pieceTypeBB[Piece.WKNIGHT];
while (knights != 0) {
sq = BitBoard.numberOfTrailingZeros(knights);
m = BitBoard.knightAttacks[sq] & ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
knights &= knights-1;
}
// Pawn moves
ulong pawns = pos.pieceTypeBB[Piece.WPAWN];
m = (pawns << 8) & ~occupied;
if (addPawnMovesByMask(moveList, pos, m, -8, true)) return moveList;
m = ((m & BitBoard.maskRow3) << 8) & ~occupied;
addPawnDoubleMovesByMask(moveList, pos, m, -16);
int epSquare = pos.getEpSquare();
ulong epMask = (epSquare >= 0) ? (1UL << epSquare) : 0L;
m = (pawns << 7) & BitBoard.maskAToGFiles & (pos.blackBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, -7, true)) return moveList;
m = (pawns << 9) & BitBoard.maskBToHFiles & (pos.blackBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, -9, true)) return moveList;
} else {
int sq = 0;
ulong m = 0;
// Queen moves
ulong squares = pos.pieceTypeBB[Piece.BQUEEN];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = (BitBoard.rookAttacks(sq, occupied) | BitBoard.bishopAttacks(sq, occupied)) & ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Rook moves
squares = pos.pieceTypeBB[Piece.BROOK];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.rookAttacks(sq, occupied) & ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Bishop moves
squares = pos.pieceTypeBB[Piece.BBISHOP];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.bishopAttacks(sq, occupied) & ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// King moves
{
sq = pos.getKingSq(false);
m = BitBoard.kingAttacks[sq] & ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
int k0 = 60;
if (sq == k0) {
ulong OO_SQ = 0x6000000000000000L;
ulong OOO_SQ = 0xE00000000000000L;
if (((pos.getCastleMask() & (1 << Position.H8_CASTLE)) != 0) &&
((OO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 + 3) == Piece.BROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 + 1)) {
setMove(moveList, k0, k0 + 2, Piece.EMPTY);
}
if (((pos.getCastleMask() & (1 << Position.A8_CASTLE)) != 0) &&
((OOO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 - 4) == Piece.BROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 - 1)) {
setMove(moveList, k0, k0 - 2, Piece.EMPTY);
}
}
}
// Knight moves
ulong knights = pos.pieceTypeBB[Piece.BKNIGHT];
while (knights != 0) {
sq = BitBoard.numberOfTrailingZeros(knights);
m = BitBoard.knightAttacks[sq] & ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
knights &= knights-1;
}
// Pawn moves
ulong pawns = pos.pieceTypeBB[Piece.BPAWN];
m = (pawns >> 8) & ~occupied;
if (addPawnMovesByMask(moveList, pos, m, 8, true)) return moveList;
m = ((m & BitBoard.maskRow6) >> 8) & ~occupied;
addPawnDoubleMovesByMask(moveList, pos, m, 16);
int epSquare = pos.getEpSquare();
ulong epMask = (epSquare >= 0) ? (1UL << epSquare) : 0L;
m = (pawns >> 9) & BitBoard.maskAToGFiles & (pos.whiteBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, 9, true)) return moveList;
m = (pawns >> 7) & BitBoard.maskBToHFiles & (pos.whiteBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, 7, true)) return moveList;
}
return moveList;
}
/** Score castling ability. */
private int castleBonus(Position pos)
{
if (pos.getCastleMask() == 0) return 0;
int k1 = kt1b[7*8+6] - kt1b[7*8+4];
int k2 = kt2b[7*8+6] - kt2b[7*8+4];
int t1 = qV + 2 * rV + 2 * bV;
int t2 = rV;
int t = pos.bMtrl - pos.bMtrlPawns;
int ks = interpolate(t, t2, k2, t1, k1);
int castleValue = ks + rt1b[7*8+5] - rt1b[7*8+7];
if (castleValue <= 0)
return 0;
ulong occupied = pos.whiteBB | pos.blackBB;
int tmp = (int) (occupied & 0x6E);
if (pos.a1Castle()) tmp |= 1;
if (pos.h1Castle()) tmp |= (1 << 7);
int wBonus = (castleValue * castleFactor[tmp]) >> 10;
tmp = (int) ((occupied >> 56) & 0x6E);
if (pos.a8Castle()) tmp |= 1;
if (pos.h8Castle()) tmp |= (1 << 7);
int bBonus = (castleValue * castleFactor[tmp]) >> 10;
return wBonus - bBonus;
}
/** Generate captures, checks, and possibly some other moves that are too hard to filter out. */
public MoveList pseudoLegalCapturesAndChecks(Position pos)
{
MoveList moveList = getMoveListObj();
ulong occupied = pos.whiteBB | pos.blackBB;
if (pos.whiteMove) {
int sq = 0;
ulong m = 0;
int bKingSq = pos.getKingSq(false);
ulong discovered = 0; // Squares that could generate discovered checks
ulong kRookAtk = BitBoard.rookAttacks(bKingSq, occupied);
if ((BitBoard.rookAttacks(bKingSq, occupied & ~kRookAtk) &
(pos.pieceTypeBB[Piece.WQUEEN] | pos.pieceTypeBB[Piece.WROOK])) != 0)
discovered |= kRookAtk;
ulong kBishAtk = BitBoard.bishopAttacks(bKingSq, occupied);
if ((BitBoard.bishopAttacks(bKingSq, occupied & ~kBishAtk) &
(pos.pieceTypeBB[Piece.WQUEEN] | pos.pieceTypeBB[Piece.WBISHOP])) != 0)
discovered |= kBishAtk;
// Queen moves
ulong squares = pos.pieceTypeBB[Piece.WQUEEN];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = (BitBoard.rookAttacks(sq, occupied) | BitBoard.bishopAttacks(sq, occupied));
if ((discovered & (1UL<<sq)) == 0) m &= (pos.blackBB | kRookAtk | kBishAtk);
m &= ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Rook moves
squares = pos.pieceTypeBB[Piece.WROOK];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.rookAttacks(sq, occupied);
if ((discovered & (1UL<<sq)) == 0) m &= (pos.blackBB | kRookAtk);
m &= ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Bishop moves
squares = pos.pieceTypeBB[Piece.WBISHOP];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.bishopAttacks(sq, occupied);
if ((discovered & (1UL<<sq)) == 0) m &= (pos.blackBB | kBishAtk);
m &= ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// King moves
{
sq = pos.getKingSq(true);
m = BitBoard.kingAttacks[sq];
m &= ((discovered & (1UL<<sq)) == 0) ? pos.blackBB : ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
int k0 = 4;
if (sq == k0) {
ulong OO_SQ = 0x60L;
ulong OOO_SQ = 0xEL;
if (((pos.getCastleMask() & (1 << Position.H1_CASTLE)) != 0) &&
((OO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 + 3) == Piece.WROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 + 1)) {
setMove(moveList, k0, k0 + 2, Piece.EMPTY);
}
if (((pos.getCastleMask() & (1 << Position.A1_CASTLE)) != 0) &&
((OOO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 - 4) == Piece.WROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 - 1)) {
setMove(moveList, k0, k0 - 2, Piece.EMPTY);
}
}
}
// Knight moves
ulong knights = pos.pieceTypeBB[Piece.WKNIGHT];
ulong kKnightAtk = BitBoard.knightAttacks[bKingSq];
while (knights != 0) {
sq = BitBoard.numberOfTrailingZeros(knights);
m = BitBoard.knightAttacks[sq] & ~pos.whiteBB;
if ((discovered & (1UL<<sq)) == 0) m &= (pos.blackBB | kKnightAtk);
m &= ~pos.whiteBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
knights &= knights-1;
}
// Pawn moves
// Captures
ulong pawns = pos.pieceTypeBB[Piece.WPAWN];
int epSquare = pos.getEpSquare();
ulong epMask = (epSquare >= 0) ? (1UL << epSquare) : 0L;
m = (pawns << 7) & BitBoard.maskAToGFiles & (pos.blackBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, -7, false)) return moveList;
m = (pawns << 9) & BitBoard.maskBToHFiles & (pos.blackBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, -9, false)) return moveList;
// Discovered checks and promotions
ulong pawnAll = discovered | BitBoard.maskRow7;
m = ((pawns & pawnAll) << 8) & ~(pos.whiteBB | pos.blackBB);
if (addPawnMovesByMask(moveList, pos, m, -8, false)) return moveList;
m = ((m & BitBoard.maskRow3) << 8) & ~(pos.whiteBB | pos.blackBB);
addPawnDoubleMovesByMask(moveList, pos, m, -16);
// Normal checks
m = ((pawns & ~pawnAll) << 8) & ~(pos.whiteBB | pos.blackBB);
if (addPawnMovesByMask(moveList, pos, m & BitBoard.bPawnAttacks[bKingSq], -8, false)) return moveList;
m = ((m & BitBoard.maskRow3) << 8) & ~(pos.whiteBB | pos.blackBB);
addPawnDoubleMovesByMask(moveList, pos, m & BitBoard.bPawnAttacks[bKingSq], -16);
} else {
int sq = 0;
ulong m = 0;
int wKingSq = pos.getKingSq(true);
ulong discovered = 0; // Squares that could generate discovered checks
ulong kRookAtk = BitBoard.rookAttacks(wKingSq, occupied);
if ((BitBoard.rookAttacks(wKingSq, occupied & ~kRookAtk) &
(pos.pieceTypeBB[Piece.BQUEEN] | pos.pieceTypeBB[Piece.BROOK])) != 0)
discovered |= kRookAtk;
ulong kBishAtk = BitBoard.bishopAttacks(wKingSq, occupied);
if ((BitBoard.bishopAttacks(wKingSq, occupied & ~kBishAtk) &
(pos.pieceTypeBB[Piece.BQUEEN] | pos.pieceTypeBB[Piece.BBISHOP])) != 0)
discovered |= kBishAtk;
// Queen moves
ulong squares = pos.pieceTypeBB[Piece.BQUEEN];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = (BitBoard.rookAttacks(sq, occupied) | BitBoard.bishopAttacks(sq, occupied));
if ((discovered & (1UL<<sq)) == 0) m &= pos.whiteBB | kRookAtk | kBishAtk;
m &= ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Rook moves
squares = pos.pieceTypeBB[Piece.BROOK];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.rookAttacks(sq, occupied);
if ((discovered & (1UL<<sq)) == 0) m &= pos.whiteBB | kRookAtk;
m &= ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// Bishop moves
squares = pos.pieceTypeBB[Piece.BBISHOP];
while (squares != 0) {
sq = BitBoard.numberOfTrailingZeros(squares);
m = BitBoard.bishopAttacks(sq, occupied);
if ((discovered & (1UL<<sq)) == 0) m &= pos.whiteBB | kBishAtk;
m &= ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
squares &= squares-1;
}
// King moves
{
sq = pos.getKingSq(false);
m = BitBoard.kingAttacks[sq];
m &= ((discovered & (1UL<<sq)) == 0) ? pos.whiteBB : ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
int k0 = 60;
if (sq == k0) {
ulong OO_SQ = 0x6000000000000000L;
ulong OOO_SQ = 0xE00000000000000L;
if (((pos.getCastleMask() & (1 << Position.H8_CASTLE)) != 0) &&
((OO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 + 3) == Piece.BROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 + 1)) {
setMove(moveList, k0, k0 + 2, Piece.EMPTY);
}
if (((pos.getCastleMask() & (1 << Position.A8_CASTLE)) != 0) &&
((OOO_SQ & (pos.whiteBB | pos.blackBB)) == 0) &&
(pos.getPiece(k0 - 4) == Piece.BROOK) &&
!sqAttacked(pos, k0) &&
!sqAttacked(pos, k0 - 1)) {
setMove(moveList, k0, k0 - 2, Piece.EMPTY);
}
}
}
// Knight moves
ulong knights = pos.pieceTypeBB[Piece.BKNIGHT];
ulong kKnightAtk = BitBoard.knightAttacks[wKingSq];
while (knights != 0) {
sq = BitBoard.numberOfTrailingZeros(knights);
m = BitBoard.knightAttacks[sq] & ~pos.blackBB;
if ((discovered & (1UL<<sq)) == 0) m &= pos.whiteBB | kKnightAtk;
m &= ~pos.blackBB;
if (addMovesByMask(moveList, pos, sq, m)) return moveList;
knights &= knights-1;
}
// Pawn moves
// Captures
ulong pawns = pos.pieceTypeBB[Piece.BPAWN];
int epSquare = pos.getEpSquare();
ulong epMask = (epSquare >= 0) ? (1UL << epSquare) : 0L;
m = (pawns >> 9) & BitBoard.maskAToGFiles & (pos.whiteBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, 9, false)) return moveList;
m = (pawns >> 7) & BitBoard.maskBToHFiles & (pos.whiteBB | epMask);
if (addPawnMovesByMask(moveList, pos, m, 7, false)) return moveList;
// Discovered checks and promotions
ulong pawnAll = discovered | BitBoard.maskRow2;
m = ((pawns & pawnAll) >> 8) & ~(pos.whiteBB | pos.blackBB);
if (addPawnMovesByMask(moveList, pos, m, 8, false)) return moveList;
m = ((m & BitBoard.maskRow6) >> 8) & ~(pos.whiteBB | pos.blackBB);
addPawnDoubleMovesByMask(moveList, pos, m, 16);
// Normal checks
m = ((pawns & ~pawnAll) >> 8) & ~(pos.whiteBB | pos.blackBB);
if (addPawnMovesByMask(moveList, pos, m & BitBoard.wPawnAttacks[wKingSq], 8, false)) return moveList;
m = ((m & BitBoard.maskRow6) >> 8) & ~(pos.whiteBB | pos.blackBB);
addPawnDoubleMovesByMask(moveList, pos, m & BitBoard.wPawnAttacks[wKingSq], 16);
}
return moveList;
}
