Give bonus for rooks that are alligned with enemy kingring

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 449cf6d7463f4ed3f716daf7af0bc91e34c50165..8e8cc0912e57ddd4e37c12cb579631eaee9de289 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -91,15 +91,15 @@ namespace {
   // MobilityBonus[PieceType-2][attacked] contains bonuses for middle and end game,
   // indexed by piece type and number of attacked squares in the mobility area.
   constexpr Score MobilityBonus[][32] = {
-    { S(-62,-81), S(-53,-56), S(-12,-30), S( -4,-14), S(  3,  8), S( 13, 15), // Knight
-      S( 22, 23), S( 28, 27), S( 33, 33) },
+    { S(-62,-81), S(-53,-56), S(-12,-31), S( -4,-16), S(  3,  5), S( 13, 11), // Knight
+      S( 22, 17), S( 28, 20), S( 33, 25) },
     { S(-48,-59), S(-20,-23), S( 16, -3), S( 26, 13), S( 38, 24), S( 51, 42), // Bishop
       S( 55, 54), S( 63, 57), S( 63, 65), S( 68, 73), S( 81, 78), S( 81, 86),
       S( 91, 88), S( 98, 97) },
     { S(-60,-78), S(-20,-17), S(  2, 23), S(  3, 39), S(  3, 70), S( 11, 99), // Rook
       S( 22,103), S( 31,121), S( 40,134), S( 40,139), S( 41,158), S( 48,164),
       S( 57,168), S( 57,169), S( 62,172) },
-    { S(-34,-36), S(-15,-21), S(-10, -1), S(-10, 22), S( 20, 41), S( 23, 56), // Queen
+    { S(-30,-48), S(-12,-30), S( -8, -7), S( -9, 19), S( 20, 40), S( 23, 55), // Queen
       S( 23, 59), S( 35, 75), S( 38, 78), S( 53, 96), S( 64, 96), S( 65,100),
       S( 65,121), S( 66,127), S( 67,131), S( 67,133), S( 72,136), S( 72,141),
       S( 77,147), S( 79,150), S( 93,151), S(108,168), S(108,168), S(108,171),
@@ -143,6 +143,7 @@ namespace {
   constexpr Score PassedFile          = S( 11,  8);
   constexpr Score PawnlessFlank       = S( 17, 95);
   constexpr Score RestrictedPiece     = S(  7,  7);
+  constexpr Score RookOnKingRing      = S( 16,  0);
   constexpr Score RookOnQueenFile     = S(  5,  9);
   constexpr Score SliderOnQueen       = S( 59, 18);
   constexpr Score ThreatByKing        = S( 24, 89);
@@ -287,6 +288,8 @@ namespace {
             kingAttackersWeight[Us] += KingAttackWeights[Pt];
             kingAttacksCount[Us] += popcount(b & attackedBy[Them][KING]);
         }
+        else if (Pt == ROOK && (file_bb(s) & kingRing[Them]))
+            score += RookOnKingRing;
 
         int mob = popcount(b & mobilityArea[Us]);
 
@@ -311,7 +314,7 @@ namespace {
 
             if (Pt == BISHOP)
             {
-                // Penalty according to number of pawns on the same color square as the
+                // Penalty according to the number of our pawns on the same color square as the
                 // bishop, bigger when the center files are blocked with pawns and smaller
                 // when the bishop is outside the pawn chain.
                 Bitboard blocked = pos.pieces(Us, PAWN) & shift<Down>(pos.pieces());