Give a small penalty for bishop for each pawn on the same colored square

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index cb5e284644e92bbbc0f548e281c1d0cc2c451fde..3481b03d7c77ad2a01622eb7abd1960ffab7ca4a 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -88,7 +88,7 @@ namespace {
   //
   // Values modified by Joona Kiiski
   const Score WeightsInternal[] = {
-      S(252, 344), S(216, 266), S(46, 0), S(247, 0), S(259, 0)
+      S(289, 344), S(221, 273), S(46, 0), S(271, 0), S(307, 0)
   };
 
   // MobilityBonus[PieceType][attacked] contains mobility bonuses for middle and
@@ -289,14 +289,6 @@ namespace Eval {
     Weights[KingDangerUs]   = weight_option("Cowardice", "Cowardice", WeightsInternal[KingDangerUs]);
     Weights[KingDangerThem] = weight_option("Aggressiveness", "Aggressiveness", WeightsInternal[KingDangerThem]);
 
-    // King safety is asymmetrical. Our king danger level is weighted by
-    // "Cowardice" UCI parameter, instead the opponent one by "Aggressiveness".
-    // If running in analysis mode, make sure we use symmetrical king safety. We
-    // do this by replacing both Weights[kingDangerUs] and Weights[kingDangerThem]
-    // by their average.
-    if (Options["UCI_AnalyseMode"])
-        Weights[KingDangerUs] = Weights[KingDangerThem] = (Weights[KingDangerUs] + Weights[KingDangerThem]) / 2;
-
     const int MaxSlope = 30;
     const int Peak = 1280;
 
@@ -590,6 +582,10 @@ Value do_evaluate(const Position& pos, Value& margin) {
                  && !more_than_one(BetweenBB[s][pos.king_square(Them)] & pos.pieces()))
                  score += BishopPinBonus;
 
+        // Penalty for bishop with same coloured pawns
+        if (Piece == BISHOP)
+            score -= make_score(4, 4) * ei.pi->same_colored_pawn_count(s, Us); 
+
         // Bishop and knight outposts squares
         if (    (Piece == BISHOP || Piece == KNIGHT)
             && !(pos.pieces(Them, PAWN) & attack_span_mask(Us, s)))