Evaluate king safety when no queen is present.

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 98ecf72de59c4c32d84210f48ff2e4c7cc3dbf00..ce98af6f8e01b50eb57ad84537dca8a533b756b3 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -221,7 +221,7 @@ namespace {
     ei.attackedBy[Us][ALL_PIECES] = ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us);
 
     // Init king safety tables only if we are going to use them
-    if (pos.count<QUEEN>(Us) && pos.non_pawn_material(Us) > QueenValueMg + PawnValueMg)
+    if (pos.non_pawn_material(Us) > QueenValueMg + PawnValueMg)
     {
         ei.kingRing[Them] = b | shift_bb<Down>(b);
         b &= ei.attackedBy[Us][PAWN];
@@ -414,7 +414,8 @@ namespace {
         attackUnits =  std::min(20, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
                      + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount<Max15>(undefended))
                      + 2 * (ei.pinnedPieces[Us] != 0)
-                     - mg_value(score) / 32;
+                     - mg_value(score) / 32
+                     - !pos.count<QUEEN>(Them) * 15;
 
         // Analyse the enemy's safe queen contact checks. Firstly, find the
         // undefended squares around the king that are attacked by the enemy's
@@ -532,7 +533,7 @@ namespace {
         b = weakEnemies & pos.pieces(Them, PAWN) & ei.attackedBy[Us][KING];
         if (b)
             score += more_than_one(b) ? KingOnPawnMany : KingOnPawnOne;
-       }
+    }
 
     if (Trace)
         Tracing::terms[Us][Tracing::THREAT] = score;