void Position::UnmakeMove()
{
if (m_undoSize == 0) return;
Undo& undo = m_undos[--m_undoSize];
Move mv = undo.m_mv;
m_ep = undo.m_ep;
m_castlings = undo.m_castlings;
m_fifty = undo.m_fifty;
FLD from = mv.From();
FLD to = mv.To();
PIECE piece = mv.Piece();
PIECE captured = mv.Captured();
COLOR side = m_side ^ 1;
m_hash ^= s_hashSide[1];
Remove(to);
Put(from, piece);
if (captured)
{
if (to == m_ep)
Put(to + 8 - 16 * side, captured);
else
Put(to, captured);
}
--m_ply;
m_side ^= 1;
if (piece == KW)
{
m_Kings[WHITE] = from;
if (from == E1 && to == G1)
{
Remove(F1);
Put(H1, RW);
}
else if (from == E1 && to == C1)
{
Remove(D1);
Put(A1, RW);
}
}
else if (piece == KB)
{
m_Kings[BLACK] = from;
if (from == E8 && to == G8)
{
Remove(F8);
Put(H8, RB);
}
else if (from == E8 && to == C8)
{
Remove(D8);
Put(A8, RB);
}
}
}
bool Position::MakeMove(Move mv)
{
Undo& undo = _undos[_undoSize++];
undo.m_castlings = m_castlings;
undo.m_ep = m_ep;
undo.m_fifty = m_fifty;
undo.m_hash = m_hash;
undo.m_mv = mv;
FLD from = mv.From();
FLD to = mv.To();
PIECE piece = mv.Piece();
PIECE captured = mv.Captured();
PIECE promotion = mv.Promotion();
COLOR side = m_side;
COLOR opp = side ^ 1;
m_hash ^= s_hashSide[1];
++m_fifty;
if (captured)
{
m_fifty = 0;
if (to == m_ep)
Remove(to + 8 - 16 * side);
else
Remove(to);
}
Remove(from);
Put(to, piece);
m_ep = NF;
switch (piece)
{
case PW:
case PB:
m_fifty = 0;
if (to - from == -16 + 32 * side)
m_ep = to + 8 - 16 * side;
else if (promotion)
{
Remove(to);
Put(to, promotion);
}
break;
case KW:
m_Kings[WHITE] = to;
if (from == E1)
{
if (to == G1)
{
Remove(H1);
Put(F1, RW);
m_castlings ^= WHITE_DID_O_O;
}
else if (to == C1)
{
Remove(A1);
Put(D1, RW);
m_castlings ^= WHITE_DID_O_O_O;
}
}
break;
case KB:
m_Kings[BLACK] = to;
if (from == E8)
{
if (to == G8)
{
Remove(H8);
Put(F8, RB);
m_castlings ^= BLACK_DID_O_O;
}
else if (to == C8)
{
Remove(A8);
Put(D8, RB);
m_castlings ^= BLACK_DID_O_O_O;
}
}
break;
default:
break;
}
static const U8 castlingDelta[64] =
{
0xf7, 0xff, 0xff, 0xff, 0xf3, 0xff, 0xff, 0xfb,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xfd, 0xff, 0xff, 0xff, 0xfc, 0xff, 0xff, 0xfe
};
m_castlings &= castlingDelta[from];
m_castlings &= castlingDelta[to];
++m_ply;
m_side ^= 1;
if (IsAttacked(m_Kings[side], opp))
{
UnmakeMove();
return false;
}
return true;
}
string MoveToStrShort(Move mv, Position& pos, MoveList* mvlist)
{
if (mv.Piece() == KW && mv.From() == E1 && mv.To() == G1) return "O-O";
if (mv.Piece() == KW && mv.From() == E1 && mv.To() == C1) return "O-O-O";
if (mv.Piece() == KB && mv.From() == E8 && mv.To() == G8) return "O-O";
if (mv.Piece() == KB && mv.From() == E8 && mv.To() == C8) return "O-O-O";
FLD from = mv.From();
FLD to = mv.To();
PIECE piece = mv.Piece();
PIECE captured = mv.Captured();
PIECE promotion = mv.Promotion();
string strPiece, strFrom, strTo, strCapture, strPromotion;
switch (piece)
{
case PW: case PB: break;
case NW: case NB: strPiece = "N"; break;
case BW: case BB: strPiece = "B"; break;
case RW: case RB: strPiece = "R"; break;
case QW: case QB: strPiece = "Q"; break;
case KW: case KB: strPiece = "K"; break;
default: break;
}
strTo = FldToStr(to);
if (captured)
{
strCapture = "x";
if (piece == PW || piece == PB)
strFrom = FldToStr(from).substr(0, 1);
}
switch (promotion)
{
case QW: case QB: strPromotion += "=Q"; break;
case RW: case RB: strPromotion += "=R"; break;
case BW: case BB: strPromotion += "=B"; break;
case NW: case NB: strPromotion += "=N"; break;
}
bool ambiguity = false;
bool uniqRow = true;
bool uniqCol = true;
if (piece != PW && piece != PB)
{
for (MoveList* ptr = mvlist; ptr->mv; ++ptr)
{
Move mv1 = ptr->mv;
if (mv1 == mv) continue;
if (mv1.To() != to) continue;
if (mv1.Piece() != piece) continue;
if (!pos.MakeMove(mv1)) continue;
pos.UnmakeMove();
ambiguity = true;
if (Row(mv1.From()) == Row(from)) uniqRow = false;
if (Col(mv1.From()) == Col(from)) uniqCol = false;
}
}
if (ambiguity)
{
if (uniqCol)
strFrom = FldToStr(from).substr(0, 1);
else if (uniqRow)
strFrom = FldToStr(from).substr(1, 1);
else
strFrom = FldToStr(from);
}
return strPiece + strFrom + strCapture + strTo + strPromotion;
}
std::string MoveToStrShort(Move mv, Position& pos)
{
if (mv == Move(E1, G1, KW) || mv == Move(E8, G8, KB))
return "O-O";
if (mv == Move(E1, C1, KW) || mv == Move(E8, C8, KB))
return "O-O-O";
PIECE piece = mv.Piece();
FLD from = mv.From();
FLD to = mv.To();
PIECE captured = mv.Captured();
PIECE promotion = mv.Promotion();
std::string strFrom, strTo, strPiece, strCaptured, strPromotion;
switch (piece)
{
case PW: case PB:
if (captured)
strFrom = FldToStr(from).substr(0, 1);
break;
case NW: case NB: strPiece = "N"; break;
case BW: case BB: strPiece = "B"; break;
case RW: case RB: strPiece = "R"; break;
case QW: case QB: strPiece = "Q"; break;
case KW: case KB: strPiece = "K"; break;
default: break;
}
if (captured)
strCaptured = "x";
strTo = FldToStr(to);
switch (promotion)
{
case QW: case QB: strPromotion = "=Q"; break;
case RW: case RB: strPromotion = "=R"; break;
case BW: case BB: strPromotion = "=B"; break;
case NW: case NB: strPromotion = "=N"; break;
default: break;
}
// resolve ambiguity
int uniq_col = 1;
int uniq_row = 1;
bool ambiguity = false;
int row0 = Row(from);
int col0 = Col(from);
MoveList mvlist;
mvlist.GenAllMoves(pos);
for (int i = 0; i < mvlist.Size(); ++i)
{
Move mvi = mvlist[i].m_mv;
if (mvi.To() != to)
continue;
if (mvi.Piece() != piece)
continue;
if (mvi.From() == from)
continue;
if (!pos.MakeMove(mvi))
continue;
pos.UnmakeMove();
ambiguity = true; // two or more pieces of the same type can move to field
int row1 = Row(mvi.From());
int col1 = Col(mvi.From());
if (row0 == row1)
uniq_row = 0;
if (col0 == col1)
uniq_col = 0;
}
if (ambiguity)
{
if (uniq_col)
strFrom = FldToStr(from).substr(0, 1);
else if (uniq_row)
strFrom = FldToStr(from).substr(1, 1);
else
strFrom = FldToStr(from);
}
return strPiece + strFrom + strCaptured + strTo + strPromotion;
}
