X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=b3c65a0f166268200fb918d4a751f2563f7de378;hp=587c9b95509224a4f396ae27ec50cf2a3aac6f50;hb=b706165527b5449fefa20bb31ac66d0274b066ea;hpb=1d0159075e916c738760b788d605b71b3736cb7c

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 587c9b95..b3c65a0f 100644
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -61,7 +61,14 @@ namespace {
     S(34,68), S(83,166), S(0, 0), S( 0, 0)
   };
 
+  const Score PawnStructureWeight = S(233, 201);
+
   #undef S
+
+  inline Score apply_weight(Score v, Score w) {
+    return make_score((int(mg_value(v)) * mg_value(w)) / 0x100,
+                      (int(eg_value(v)) * eg_value(w)) / 0x100);
+  }
 }
 
 
@@ -72,8 +79,6 @@ namespace {
 
 PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const {
 
-  assert(pos.is_ok());
-
   Key key = pos.get_pawn_key();
   PawnInfo* pi = probe(key);
 
@@ -95,9 +100,12 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const {
   pi->pawnAttacks[WHITE] = ((wPawns << 9) & ~FileABB) | ((wPawns << 7) & ~FileHBB);
   pi->pawnAttacks[BLACK] = ((bPawns >> 7) & ~FileABB) | ((bPawns >> 9) & ~FileHBB);
 
-  // Evaluate pawns for both colors
+  // Evaluate pawns for both colors and weight the result
   pi->value =  evaluate_pawns<WHITE>(pos, wPawns, bPawns, pi)
              - evaluate_pawns<BLACK>(pos, bPawns, wPawns, pi);
+
+  pi->value = apply_weight(pi->value, PawnStructureWeight);
+
   return pi;
 }
 
@@ -117,10 +125,10 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns,
   Rank r;
   bool passed, isolated, doubled, opposed, chain, backward, candidate;
   Score value = SCORE_ZERO;
-  const Square* ptr = pos.piece_list_begin(Us, PAWN);
+  const Square* pl = pos.piece_list(Us, PAWN);
 
   // Loop through all pawns of the current color and score each pawn
-  while ((s = *ptr++) != SQ_NONE)
+  while ((s = *pl++) != SQ_NONE)
   {
       assert(pos.piece_on(s) == make_piece(Us, PAWN));
 
@@ -220,7 +228,7 @@ Score PawnInfo::updateShelter(const Position& pos, Square ksq) {
       for (int i = 0; i < 3; i++)
       {
           r += Shift;
-          shelter += BitCount8Bit[(pawns >> r) & 0xFF] * (64 >> i);
+          shelter += BitCount8Bit[(pawns >> r) & 0xFF] << (6 - i);
       }
   }
   kingSquares[Us] = ksq;