Remove Overload bonus

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 297d8c65070c0118d71e4a54f819dcf72e19e6d5..f1bb861dcca629e08de695df7bb0c8ff4ccf0b2f 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -2,7 +2,7 @@
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
   Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
-  Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+  Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -152,25 +152,25 @@ namespace {
   };
 
   // Assorted bonuses and penalties
-  constexpr Score BishopPawns        = S(  3,  7);
-  constexpr Score CloseEnemies       = S(  6,  0);
+  constexpr Score BishopPawns        = S(  3,  8);
+  constexpr Score CloseEnemies       = S(  7,  0);
   constexpr Score CorneredBishop     = S( 50, 50);
-  constexpr Score Hanging            = S( 57, 32);
-  constexpr Score KingProtector      = S(  6,  6);
-  constexpr Score KnightOnQueen      = S( 21, 11);
-  constexpr Score LongDiagonalBishop = S( 46,  0);
+  constexpr Score Hanging            = S( 62, 34);
+  constexpr Score KingProtector      = S(  6,  7);
+  constexpr Score KnightOnQueen      = S( 20, 12);
+  constexpr Score LongDiagonalBishop = S( 44,  0);
   constexpr Score MinorBehindPawn    = S( 16,  0);
-  constexpr Score Overload           = S( 13,  6);
-  constexpr Score PawnlessFlank      = S( 19, 84);
-  constexpr Score RookOnPawn         = S( 10, 29);
-  constexpr Score SliderOnQueen      = S( 42, 21);
-  constexpr Score ThreatByKing       = S( 22, 78);
-  constexpr Score ThreatByPawnPush   = S( 45, 40);
-  constexpr Score ThreatByRank       = S( 16,  3);
-  constexpr Score ThreatBySafePawn   = S(173,102);
-  constexpr Score TrappedRook        = S( 96,  5);
-  constexpr Score WeakQueen          = S( 50, 10);
-  constexpr Score WeakUnopposedPawn  = S( 15, 19);
+  constexpr Score PawnlessFlank      = S( 18, 94);
+  constexpr Score RestrictedPiece    = S(  7,  6);
+  constexpr Score RookOnPawn         = S( 10, 28);
+  constexpr Score SliderOnQueen      = S( 49, 21);
+  constexpr Score ThreatByKing       = S( 21, 84);
+  constexpr Score ThreatByPawnPush   = S( 48, 42);
+  constexpr Score ThreatByRank       = S( 14,  3);
+  constexpr Score ThreatBySafePawn   = S(169, 99);
+  constexpr Score TrappedRook        = S( 98,  5);
+  constexpr Score WeakQueen          = S( 51, 10);
+  constexpr Score WeakUnopposedPawn  = S( 14, 20);
 
 #undef S
 
@@ -257,6 +257,7 @@ namespace {
     attackedBy[Us][PAWN] = pe->pawn_attacks(Us);
     attackedBy[Us][ALL_PIECES] = attackedBy[Us][KING] | attackedBy[Us][PAWN];
     attackedBy2[Us]            = attackedBy[Us][KING] & attackedBy[Us][PAWN];
+
     kingRing[Us] = kingAttackersCount[Them] = 0;
 
     // Init our king safety tables only if we are going to use them
@@ -473,7 +474,7 @@ namespace {
                      +  69 * kingAttacksCount[Them]
                      + 185 * popcount(kingRing[Us] & weak)
                      + 150 * popcount(pos.blockers_for_king(Us) | unsafeChecks)
-                     +   4 * tropism
+                     +       tropism * tropism / 4
                      - 873 * !pos.count<QUEEN>(Them)
                      -   6 * mg_value(score) / 8
                      +       mg_value(mobility[Them] - mobility[Us])
@@ -507,7 +508,7 @@ namespace {
     constexpr Direction Up       = (Us == WHITE ? NORTH   : SOUTH);
     constexpr Bitboard  TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
 
-    Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safe;
+    Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safe, restricted;
     Score score = SCORE_ZERO;
 
     // Non-pawn enemies
@@ -551,12 +552,18 @@ namespace {
         if (weak & attackedBy[Us][KING])
             score += ThreatByKing;
 
-        score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]);
-
-        b = weak & nonPawnEnemies & attackedBy[Them][ALL_PIECES];
-        score += Overload * popcount(b);
+        b =  ~attackedBy[Them][ALL_PIECES]
+           | (nonPawnEnemies & attackedBy2[Us]);
+        score += Hanging * popcount(weak & b);
     }
 
+    // Bonus for restricting their piece moves
+    restricted =   attackedBy[Them][ALL_PIECES]
+                & ~attackedBy[Them][PAWN]
+                & ~attackedBy2[Them]
+                &  attackedBy[Us][ALL_PIECES];
+    score += RestrictedPiece * popcount(restricted);
+
     // Bonus for enemy unopposed weak pawns
     if (pos.pieces(Us, ROOK, QUEEN))
         score += WeakUnopposedPawn * pe->weak_unopposed(Them);