Use single value for KingProtector.

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 2fb0e55a9d47b08ed61fa7319aca386200140390..b1e94ab7cf86e38a5765fbd465709e3cbfecdcfd 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -154,9 +154,6 @@ namespace {
   // PassedDanger[Rank] contains a term to weight the passed score
   constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 3, 7, 11, 20 };
 
-  // KingProtector[knight/bishop] contains a penalty according to distance from king
-  constexpr Score KingProtector[] = { S(5, 6), S(6, 5) };
-
   // Assorted bonuses and penalties
   constexpr Score BishopPawns        = S(  3,  7);
   constexpr Score CloseEnemies       = S(  6,  0);
@@ -164,6 +161,7 @@ namespace {
   constexpr Score CorneredBishop     = S( 50, 50);
   constexpr Score Hanging            = S( 52, 30);
   constexpr Score HinderPassedPawn   = S(  4,  0);
+  constexpr Score KingProtector      = S(  6,  6);
   constexpr Score KnightOnQueen      = S( 21, 11);
   constexpr Score LongDiagonalBishop = S( 22,  0);
   constexpr Score MinorBehindPawn    = S( 16,  0);
@@ -342,7 +340,7 @@ namespace {
                 score += MinorBehindPawn;
 
             // Penalty if the piece is far from the king
-            score -= KingProtector[Pt == BISHOP] * distance(s, pos.square<KING>(Us));
+            score -= KingProtector * distance(s, pos.square<KING>(Us));
 
             if (Pt == BISHOP)
             {