No influence on unsafeSquares of passers by pieces

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 8b017a5c880e8d1321cc2279ad6a97c097402ccb..23af60f36aede2d1adfa93eed2a04d56b8bd11a8 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -133,7 +133,6 @@ namespace {
   };
 
   // Assorted bonuses and penalties
-  constexpr Score AttacksOnSpaceArea = S(  4,  0);
   constexpr Score BishopPawns        = S(  3,  7);
   constexpr Score CorneredBishop     = S( 50, 50);
   constexpr Score FlankAttacks       = S(  8,  0);
@@ -642,7 +641,7 @@ namespace {
                 bb = forward_file_bb(Them, s) & pos.pieces(ROOK, QUEEN);
 
                 if (!(pos.pieces(Them) & bb))
-                    unsafeSquares &= attackedBy[Them][ALL_PIECES] | pos.pieces(Them);
+                    unsafeSquares &= attackedBy[Them][ALL_PIECES];
 
                 // If there are no enemy attacks on passed pawn span, assign a big bonus.
                 // Otherwise assign a smaller bonus if the path to queen is not attacked
@@ -663,7 +662,7 @@ namespace {
         // Scale down bonus for candidate passers which need more than one
         // pawn push to become passed, or have a pawn in front of them.
         if (   !pos.pawn_passed(Us, s + Up)
-            || (pos.pieces(PAWN) & forward_file_bb(Us, s)))
+            || (pos.pieces(PAWN) & (s + Up)))
             bonus = bonus / 2;
 
         score += bonus + PassedFile[file_of(s)];
@@ -705,12 +704,10 @@ namespace {
     behind |= shift<Down>(behind);
     behind |= shift<Down+Down>(behind);
 
-    int bonus = popcount(safe) + popcount(behind & safe);
+    int bonus = popcount(safe) + popcount(behind & safe & ~attackedBy[Them][ALL_PIECES]);
     int weight = pos.count<ALL_PIECES>(Us) - 1;
     Score score = make_score(bonus * weight * weight / 16, 0);
 
-    score -= AttacksOnSpaceArea * popcount(attackedBy[Them][ALL_PIECES] & behind & safe);
-
     if (T)
         Trace::add(SPACE, Us, score);