Simplify previous condition

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 5a8a292f9a24c34596309562f6c86c79a29fb4c0..fe4eef57493c8ed3a601120dc7fee3233e7a1b5d 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -642,31 +642,19 @@ Value do_evaluate(const Position& pos, Value& margin) {
                     score += RookHalfOpenFileBonus;
             }
 
-            // Penalize rooks which are trapped inside a king. Penalize more if
-            // king has lost right to castle.
             if (mob > 6 || ei.pi->file_is_half_open(Us, f))
                 continue;
 
             ksq = pos.king_square(Us);
 
-            if (    file_of(ksq) >= FILE_E
-                &&  file_of(s) > file_of(ksq)
-                && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(s)))
-            {
-                // Is there a half-open file between the king and the edge of the board?
-                if (!ei.pi->has_open_file_to_right(Us, file_of(ksq)))
-                    score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
-                                                           : (TrappedRookPenalty - mob * 16), 0);
-            }
-            else if (    file_of(ksq) <= FILE_D
-                     &&  file_of(s) < file_of(ksq)
-                     && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(s)))
-            {
-                // Is there a half-open file between the king and the edge of the board?
-                if (!ei.pi->has_open_file_to_left(Us, file_of(ksq)))
-                    score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
-                                                           : (TrappedRookPenalty - mob * 16), 0);
-            }
+            // Penalize rooks which are trapped inside a king. Penalize more if
+            // king has lost right to castle.
+            if (   ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq)))
+                && rank_of(ksq) == rank_of(s)
+                && relative_rank(Us, ksq) == RANK_1
+                && !ei.pi->has_open_file_on_side(Us, file_of(ksq), file_of(ksq) < FILE_E))
+                score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
+                                                       : (TrappedRookPenalty - mob * 16), 0);
         }
     }