Add bonuses for Minors attacking enemy pieces(except pawns) even when they are protec...

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 7fb3a8cb141d4294c969b8292b4e4ca3c288813b..f17c575d2cfeb775a5c54afacf6875988becde80 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -496,9 +496,17 @@ namespace {
 
     const Color Them = (Us == WHITE ? BLACK : WHITE);
 
-    Bitboard b, weakEnemies;
+    Bitboard b, weakEnemies, protectedEnemies;
     Score score = SCORE_ZERO;
 
+    // Protected enemies
+    protectedEnemies = (pos.pieces(Them) ^ pos.pieces(Them,PAWN))
+                      & ei.attackedBy[Them][PAWN]
+                      & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]);
+
+    if(protectedEnemies)
+        score += Threat[0][type_of(pos.piece_on(lsb(protectedEnemies)))];
+
     // Enemies not defended by a pawn and under our attack
     weakEnemies =  pos.pieces(Them)
                  & ~ei.attackedBy[Them][PAWN]