X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=ad76fc8d727b145e5815cafcc44e5f1e094cbc47;hp=cb1ad1f420060ef6d7fa1e0b076f1a04ac3388b3;hb=e5cfa14f40a38d99d11a9c048c34858e3145fbcd;hpb=36e4a86c08a4b79965d819b7893709245cad840a

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index cb1ad1f4..ad76fc8d 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -347,8 +347,8 @@ namespace {
             if (relative_rank(Us, s) >= RANK_5)
                 score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]);
 
-            // Bonus for rook on same file as their queen
-            if (file_bb(s) & pos.pieces(Them, QUEEN))
+            // Bonus for rook on the same file as a queen
+            if (file_bb(s) & pos.pieces(QUEEN))
                 score += RookOnQueenFile;
 
             // Bonus for rook on an open or semi-open file
@@ -725,12 +725,17 @@ namespace {
     bool pawnsOnBothFlanks =   (pos.pieces(PAWN) & QueenSide)
                             && (pos.pieces(PAWN) & KingSide);
 
+    bool almostUnwinnable =   !pe->passed_count()
+                           &&  outflanking < 0
+                           && !pawnsOnBothFlanks;
+
     // Compute the initiative bonus for the attacking side
     int complexity =   9 * pe->passed_count()
                     + 11 * pos.count<PAWN>()
                     +  9 * outflanking
                     + 18 * pawnsOnBothFlanks
                     + 49 * !pos.non_pawn_material()
+                    - 36 * almostUnwinnable
                     -103 ;
 
     // Now apply the bonus: note that we find the attacking side by extracting