Small Queen simplification

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 58058b1ba53b7b31d9923922526e03ec956f99ed..068aad9a7d590c7ccbb74c691148ec95b751b641 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -211,10 +211,10 @@ namespace {
 
   // Penalties for enemy's safe checks
   const int QueenContactCheck = 89;
-  const int QueenCheck        = 52;
-  const int RookCheck         = 45;
-  const int BishopCheck       = 5;
-  const int KnightCheck       = 17;
+  const int QueenCheck        = 62;
+  const int RookCheck         = 57;
+  const int BishopCheck       = 48;
+  const int KnightCheck       = 78;
 
 
   // eval_init() initializes king and attack bitboards for a given color
@@ -348,6 +348,13 @@ namespace {
                     score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us));
             }
         }
+
+        if (Pt == QUEEN)
+        {
+            // Penalty if any relative pin or discovered attack against the queen
+            if (pos.slider_blockers(pos.pieces(), pos.pieces(Them, ROOK, BISHOP), s))
+                score -= WeakQueen;
+        }
     }
 
     if (DoTrace)
@@ -399,8 +406,8 @@ namespace {
         // the pawn shelter (current 'score' value).
         attackUnits =  std::min(72, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them])
                      +  9 * ei.kingAdjacentZoneAttacksCount[Them]
-                     + 27 * popcount(undefended)
-                     + 11 * (popcount(b) + !!ei.pinnedPieces[Us])
+                     + 21 * popcount(undefended)
+                     + 12 * (popcount(b) + !!ei.pinnedPieces[Us])
                      - 64 * !pos.count<QUEEN>(Them)
                      - mg_value(score) / 8;
 
@@ -489,13 +496,6 @@ namespace {
         & ~(ei.attackedBy[Us][ALL_PIECES] | ei.attackedBy[Them][ALL_PIECES]))
         score += LooseEnemies;
 
-    // Bonus for pin or discovered attack on the opponent queen
-    if (   pos.count<QUEEN>(Them) == 1
-        && pos.slider_blockers(pos.pieces(),
-                               pos.pieces(Us, ROOK, BISHOP),
-                               pos.square<QUEEN>(Them)))
-        score += WeakQueen;
-
     // Non-pawn enemies attacked by a pawn
     weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Us][PAWN];