Bench: 3511579

ElbertoOne · Jan 24, 2019 · 5a7f074 · 5a7f074
1 parent d20458f
commit 5a7f074
Showing 1 changed file with 15 additions and 18 deletions.
diff --git a/src/evaluate.cpp b/src/evaluate.cpp
@@ -626,16 +626,25 @@ namespace {
         int r = relative_rank(Us, s);
 
         Score bonus = PassedRank[r];
-        Square blockSq = s + Up;
 
         if (r > RANK_3)
         {
             int w = (r-2) * (r-2) + 2;
+            Square blockSq = s + Up;
 
             // Adjust bonus based on the king's proximity
             bonus += make_score(0, (  king_proximity(Them, blockSq) * 5
                                     - king_proximity(Us,   blockSq) * 2) * w);
 
+            bool supportingMinors = pos.count<KNIGHT>(Us) > 0 || pos.count<BISHOP>(Us) == 2;
+            if (!supportingMinors && pos.count<BISHOP>(Us) == 1)
+            {
+                File f = file_of(blockSq);
+                Square queeningSq = make_square(f, Us == WHITE ? RANK_8 : RANK_1);
+                Square sb = pos.square<BISHOP>(Us);
+                supportingMinors = !opposite_colors(queeningSq, sb);
+            }
+
             // If blockSq is not the queening square then consider also a second push
             if (r != RANK_7)
                 bonus -= make_score(0, king_proximity(Us, blockSq + Up) * w);
@@ -668,8 +677,13 @@ namespace {
                 else if (defendedSquares & blockSq)
                     k += 4;
 
+                if (k > 0 && !supportingMinors)
+                    k -= 2;
+
                 bonus += make_score(k * w, k * w);
             }
+            else if (!supportingMinors) //block square is occupied and there are no minors to help reach the queening square
+                bonus = bonus / 2;
         } // rank > RANK_3
 
 
@@ -678,23 +692,6 @@ namespace {
         if (   !pos.pawn_passed(Us, s + Up)
             || (pos.pieces(PAWN) & forward_file_bb(Us, s)))
             bonus = bonus / 2;
-        // Scale down bonus if queening square is defended and there are no minors that could help with queening
-        else if (r == RANK_7 && !pos.pieces(Us, KNIGHT) && ((attackedBy[Them][ALL_PIECES] | pos.pieces(Them)) & blockSq))
-        {
-            bool hasBishops = false;
-            Bitboard bbs = pos.pieces(Us, BISHOP);
-            while (bbs)
-            {
-                Square sb = pop_lsb(&bbs);
-                if (!opposite_colors(blockSq, sb))
-                {
-                    hasBishops = true;
-                    break;
-                }
-            }
-            if (!hasBishops)
-                bonus = bonus / 2;
-        }
 
         score += bonus + PassedFile[file_of(s)];
     }