Value DrawValue[COLOR_NB];
History Hist;
Gains Gain;
+ RefutationTable Refutation;
template <NodeType NT>
Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth);
// Init futility move count array
for (d = 0; d < 32; d++)
- FutilityMoveCounts[d] = int(3.001 + 0.25 * pow(double(d), 2.0));
+ FutilityMoveCounts[d] = int(3.001 + 0.3 * pow(double(d), 1.8));
}
TT.new_search();
Hist.clear();
Gain.clear();
+ Refutation.clear();
PVSize = Options["MultiPV"];
Skill skill(Options["Skill Level"]);
split_point_start: // At split points actual search starts from here
- MovePicker mp(pos, ttMove, depth, Hist, ss, PvNode ? -VALUE_INFINITE : beta);
+ Move prevMove = (ss-1)->currentMove;
+ Square prevSq = to_sq(prevMove);
+ Piece prevP = pos.piece_on(prevSq);
+ Move refutationMove = Refutation.get(prevP, prevSq);
+
+ MovePicker mp(pos, ttMove, depth, Hist, ss, refutationMove, PvNode ? -VALUE_INFINITE : beta);
CheckInfo ci(pos);
value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
singularExtensionNode = !RootNode
// Increase history value of the cut-off move
Value bonus = Value(int(depth) * int(depth));
Hist.update(pos.piece_moved(bestMove), to_sq(bestMove), bonus);
+ Refutation.update(prevP, prevSq, bestMove);
// Decrease history of all the other played non-capture moves
for (int i = 0; i < playedMoveCount - 1; i++)