Remove undefended minors

Tested in "no regression" mode.

Passed both STC
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 68026 W: 12277 L: 12236 D: 43513

And LTC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 85682 W: 12861 L: 12836 D: 59985

bench: 7311935

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 341b50682f64dac590dd07ac89917c1a25fa8b1a..64b1bf4cf750d8d0902ce6f9d22c189eb175480b 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -169,7 +169,6 @@ namespace {
   const Score RookSemiopenFile = make_score(19, 10);
   const Score BishopPawns      = make_score( 8, 12);
   const Score MinorBehindPawn  = make_score(16,  0);
   const Score RookSemiopenFile = make_score(19, 10);
   const Score BishopPawns      = make_score( 8, 12);
   const Score MinorBehindPawn  = make_score(16,  0);

-  const Score UndefendedMinor  = make_score(25, 10);

   const Score TrappedRook      = make_score(90,  0);
   const Score Unstoppable      = make_score( 0, 20);
 
   const Score TrappedRook      = make_score(90,  0);
   const Score Unstoppable      = make_score( 0, 20);
 


@@ -520,16 +519,9 @@ namespace {
 
     const Color Them = (Us == WHITE ? BLACK : WHITE);
 
 
     const Color Them = (Us == WHITE ? BLACK : WHITE);
 

-    Bitboard b, undefendedMinors, weakEnemies;
+    Bitboard b, weakEnemies;

     Score score = SCORE_ZERO;
 
     Score score = SCORE_ZERO;
 

-    // Undefended minors get penalized even if they are not under attack
-    undefendedMinors =  pos.pieces(Them, BISHOP, KNIGHT)
-                      & ~ei.attackedBy[Them][ALL_PIECES];
-
-    if (undefendedMinors)
-        score += UndefendedMinor;
-

     // Enemies not defended by a pawn and under our attack
     weakEnemies =  pos.pieces(Them)
                  & ~ei.attackedBy[Them][PAWN]
     // Enemies not defended by a pawn and under our attack
     weakEnemies =  pos.pieces(Them)
                  & ~ei.attackedBy[Them][PAWN]