X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=ac9cf90bdcb314aad1198af283f0ab8d9662eb6c;hp=76ffcf039a65622a978520c0353e493801bcff59;hb=a4eda3056ef7f6f69ae15925255621cb32443de9;hpb=38471697b7e414f4509fb7dbf41f3f679711edb4

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 76ffcf03..ac9cf90b 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -540,6 +540,9 @@ namespace {
             score += ThreatByMinor[type_of(pos.piece_on(s))];
             if (type_of(pos.piece_on(s)) != PAWN)
                 score += ThreatByRank * (int)relative_rank(Them, s);
+
+            else if (pos.blockers_for_king(Them) & s)
+                score += ThreatByRank * (int)relative_rank(Them, s) / 2;
         }
 
         b = weak & attackedBy[Us][ROOK];
@@ -549,9 +552,11 @@ namespace {
             score += ThreatByRook[type_of(pos.piece_on(s))];
             if (type_of(pos.piece_on(s)) != PAWN)
                 score += ThreatByRank * (int)relative_rank(Them, s);
+
+            else if (pos.blockers_for_king(Them) & s)
+                score += ThreatByRank * (int)relative_rank(Them, s) / 2;
         }
 
-        // Bonus for king attacks on pawns or pieces which are not pawn-defended
         if (weak & attackedBy[Us][KING])
             score += ThreatByKing;
 
@@ -576,7 +581,7 @@ namespace {
     b  = shift<Up>(pos.pieces(Us, PAWN)) & ~pos.pieces();
     b |= shift<Up>(b & TRank3BB) & ~pos.pieces();
 
-    // Keep only the squares which are not completely unsafe
+    // Keep only the squares which are relatively safe
     b &= ~attackedBy[Them][PAWN]
         & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]);