Assorted trivial cleanups 5/2019

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 86f73563ef262a9e2914597320b0adfef8818e59..3ff1460b562742a12c3f79883839d3b7db69e914 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -74,7 +74,7 @@ using namespace Trace;
 namespace {
 
   // Threshold for lazy and space evaluation
-  constexpr Value LazyThreshold  = Value(1500);
+  constexpr Value LazyThreshold  = Value(1400);
   constexpr Value SpaceThreshold = Value(12222);
 
   // KingAttackWeights[PieceType] contains king attack weights by piece type
@@ -141,7 +141,7 @@ namespace {
   constexpr Score KnightOnQueen      = S( 16, 12);
   constexpr Score LongDiagonalBishop = S( 45,  0);
   constexpr Score MinorBehindPawn    = S( 18,  3);
-  constexpr Score Outpost            = S(  9,  3);
+  constexpr Score Outpost            = S( 36, 12);
   constexpr Score PawnlessFlank      = S( 17, 95);
   constexpr Score RestrictedPiece    = S(  7,  7);
   constexpr Score RookOnPawn         = S( 10, 32);
@@ -152,7 +152,6 @@ namespace {
   constexpr Score ThreatBySafePawn   = S(173, 94);
   constexpr Score TrappedRook        = S( 47,  4);
   constexpr Score WeakQueen          = S( 49, 15);
-  constexpr Score WeakUnopposedPawn  = S( 12, 23);
 
 #undef S
 
@@ -191,10 +190,8 @@ namespace {
     // color, including x-rays. But diagonal x-rays through pawns are not computed.
     Bitboard attackedBy2[COLOR_NB];
 
-    // kingRing[color] are the squares adjacent to the king, plus (only for a
-    // king on its first rank) the squares two ranks in front. For instance,
-    // if black's king is on g8, kingRing[BLACK] is f8, h8, f7, g7, h7, f6, g6
-    // and h6.
+    // kingRing[color] are the squares adjacent to the king plus some other
+    // very near squares, depending on king position.
     Bitboard kingRing[COLOR_NB];
 
     // kingAttackersCount[color] is the number of pieces of the given color
@@ -305,14 +302,12 @@ namespace {
         if (Pt == BISHOP || Pt == KNIGHT)
         {
             // Bonus if piece is on an outpost square or can reach one
-            bb = OutpostRanks & ~pe->pawn_attacks_span(Them);
+            bb = OutpostRanks & attackedBy[Us][PAWN] & ~pe->pawn_attacks_span(Them);
             if (bb & s)
-                score += Outpost * (Pt == KNIGHT ? 4 : 2)
-                                 * ((attackedBy[Us][PAWN] & s) ? 2 : 1);
+                score += Outpost * (Pt == KNIGHT ? 2 : 1);
 
-            else if (bb &= b & ~pos.pieces(Us))
-                score += Outpost * (Pt == KNIGHT ? 2 : 1)
-                                 * ((attackedBy[Us][PAWN] & bb) ? 2 : 1);
+            else if (bb & b & ~pos.pieces(Us))
+                score += Outpost / (Pt == KNIGHT ? 1 : 2);
 
             // Knight and Bishop bonus for being right behind a pawn
             if (shift<Down>(pos.pieces(PAWN)) & s)
@@ -557,10 +552,6 @@ namespace {
 
     score += RestrictedPiece * popcount(b);
 
-    // Bonus for enemy unopposed weak pawns
-    if (pos.pieces(Us, ROOK, QUEEN))
-        score += WeakUnopposedPawn * pe->weak_unopposed(Them);
-
     // Find squares where our pawns can push on the next move
     b  = shift<Up>(pos.pieces(Us, PAWN)) & ~pos.pieces();
     b |= shift<Up>(b & TRank3BB) & ~pos.pieces();
@@ -661,13 +652,9 @@ namespace {
                 // assign a smaller bonus if the block square isn't attacked.
                 int k = !unsafeSquares ? 20 : !(unsafeSquares & blockSq) ? 9 : 0;
 
-                // If the path to the queen is fully defended, assign a big bonus.
-                // Otherwise assign a smaller bonus if the block square is defended.
-                if (defendedSquares == squaresToQueen)
-                    k += 6;
-
-                else if (defendedSquares & blockSq)
-                    k += 4;
+                // Assign a larger bonus if the block square is defended.
+                if (defendedSquares & blockSq)
+                    k += 5;
 
                 bonus += make_score(k * w, k * w);
             }
@@ -813,7 +800,7 @@ namespace {
 
     // Early exit if score is high
     Value v = (mg_value(score) + eg_value(score)) / 2;
-    if (abs(v) > LazyThreshold)
+    if (abs(v) > LazyThreshold + pos.non_pawn_material() / 64)
        return pos.side_to_move() == WHITE ? v : -v;
 
     // Main evaluation begins here