X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fevaluate.cpp;h=d6239594d9165cb91578311a353e801851ac724e;hb=090e49547ecaba8c9ec696d75f2fca3020bb058a;hp=3872dd4053994fac66f9845bff2ed42a67599ccd;hpb=b92206305fb9a246c4a86a1f5235e47b70fb63ed;p=stockfish

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 3872dd40..d6239594 100644
--- 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
@@ -160,8 +160,8 @@ namespace {
   constexpr Score KnightOnQueen      = S( 20, 12);
   constexpr Score LongDiagonalBishop = S( 44,  0);
   constexpr Score MinorBehindPawn    = S( 16,  0);
-  constexpr Score Overload           = S( 12,  6);
   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);
@@ -309,7 +309,7 @@ namespace {
         attackedBy[Us][Pt] |= b;
         attackedBy[Us][ALL_PIECES] |= b;
 
-        if (b & kingRing[Them])
+        if (b & kingRing[Them] & ~double_pawn_attacks_bb<Them>(pos.pieces(Them, PAWN)))
         {
             kingAttackersCount[Us]++;
             kingAttackersWeight[Us] += KingAttackWeights[Pt];
@@ -474,7 +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])
@@ -508,7 +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
@@ -552,12 +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);