/// Constructors of the MovePicker class. As arguments we pass information
/// to help it to return the (presumably) good moves first, to decide which
/// moves to return (in the quiescence search, for instance, we only want to
/// search captures, promotions and some checks) and how important good move
/// ordering is at the current node.
internal MovePicker(
Position p,
MoveT ttm,
Depth d,
HistoryStats h,
CounterMovesHistoryStats cmh,
MoveT cm,
StackArrayWrapper s)
{
endBadCaptures = new ExtMoveArrayWrapper(moves, _.MAX_MOVES - 1);
cur = new ExtMoveArrayWrapper(moves);
endMoves = new ExtMoveArrayWrapper(moves);
pos = p;
history = h;
counterMovesHistory = cmh;
ss = s;
countermove = cm;
depth = d;
Debug.Assert(d > Depth.DEPTH_ZERO);
stage = pos.checkers() != 0 ? Stages.EVASION : Stages.MAIN_SEARCH;
ttMove = ttm != 0 && pos.pseudo_legal(ttm) ? ttm : Move.MOVE_NONE;
endMoves += ttMove != Move.MOVE_NONE ? 1 : 0;
}
internal MovePicker(Position p, MoveT ttm, Depth d, HistoryStats h, CounterMovesHistoryStats cmh, SquareT s)
{
endBadCaptures = new ExtMoveArrayWrapper(moves, _.MAX_MOVES - 1);
cur = new ExtMoveArrayWrapper(moves);
endMoves = new ExtMoveArrayWrapper(moves);
pos = p;
history = h;
counterMovesHistory = cmh;
Debug.Assert(d <= Depth.DEPTH_ZERO_C);
if (pos.checkers() != 0)
{
stage = Stages.EVASION;
}
else if (d > Depth.DEPTH_QS_NO_CHECKS)
{
stage = Stages.QSEARCH_WITH_CHECKS;
}
else if (d > Depth.DEPTH_QS_RECAPTURES)
{
stage = Stages.QSEARCH_WITHOUT_CHECKS;
}
else
{
stage = Stages.RECAPTURE;
recaptureSquare = s;
ttm = Move.MOVE_NONE;
}
ttMove = ttm != 0 && pos.pseudo_legal(ttm) ? ttm : Move.MOVE_NONE;
endMoves += (ttMove != Move.MOVE_NONE) ? 1 : 0;
}
/// Search::reset() clears all search memory, to obtain reproducible search results
internal static void reset()
{
TranspositionTable.clear();
History = new HistoryStats();
CounterMovesHistory = new CounterMovesHistoryStats();
Countermoves = new MovesStats();
}
internal MovePicker(Position p, MoveT ttm, HistoryStats h, CounterMovesHistoryStats cmh, ValueT th)
{
endBadCaptures = new ExtMoveArrayWrapper(moves, _.MAX_MOVES - 1);
cur = new ExtMoveArrayWrapper(moves);
endMoves = new ExtMoveArrayWrapper(moves);
pos = p;
history = h;
counterMovesHistory = cmh;
threshold = th;
Debug.Assert(pos.checkers() == 0);
stage = Stages.PROBCUT;
// In ProbCut we generate captures with SEE higher than the given threshold
ttMove = ttm != 0 && pos.pseudo_legal(ttm) && pos.capture(ttm)
&& pos.see(ttm) > threshold
? ttm
: Move.MOVE_NONE;
endMoves += (ttMove != Move.MOVE_NONE) ? 1 : 0;
}
