make DistanceRing more consistent

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 1131b5e81a77cc4a02fc2133ef2221ea97fdf873..5048d4f19782b0d9e7c5a4baa6dfc2700aaa1ed1 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -32,9 +32,9 @@ namespace {
   #define S(mg, eg) make_score(mg, eg)
 
   // Pawn penalties
-  constexpr Score Isolated = S( 4, 20);
-  constexpr Score Backward = S(21, 22);
-  constexpr Score Doubled  = S(12, 54);
+ constexpr Score Isolated = S( 5, 15);
+ constexpr Score Backward = S( 9, 24);
+ constexpr Score Doubled  = S(11, 56);
 
   // Connected pawn bonus by opposed, phalanx, #support and rank
   Score Connected[2][2][3][RANK_NB];
@@ -42,25 +42,25 @@ namespace {
   // Strength of pawn shelter for our king by [distance from edge][rank].
   // RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king.
   constexpr Value ShelterStrength[int(FILE_NB) / 2][RANK_NB] = {
-    { V( 16), V(82), V( 83), V( 47), V( 19), V( 44), V(  4) },
-    { V(-51), V(56), V( 33), V(-58), V(-57), V(-50), V(-39) },
-    { V(-20), V(71), V( 16), V(-10), V( 13), V( 19), V(-30) },
-    { V(-29), V(12), V(-21), V(-40), V(-15), V(-77), V(-91) }
+    { V( -6), V( 81), V( 93), V( 58), V( 39), V( 18), V(  25) },
+    { V(-43), V( 61), V( 35), V(-49), V(-29), V(-11), V( -63) },
+    { V(-10), V( 75), V( 23), V( -2), V( 32), V(  3), V( -45) },
+    { V(-39), V(-13), V(-29), V(-52), V(-48), V(-67), V(-166) }
   };
 
   // Danger of enemy pawns moving toward our king by [distance from edge][rank].
   // RANK_1 = 0 is used for files where the enemy has no pawn, or their pawn
   // is behind our king.
   constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
-    { V(54), V( 48), V( 99), V(91), V(42), V( 32), V( 31) },
-    { V(34), V( 27), V(105), V(38), V(32), V(-19), V(  3) },
-    { V(-4), V( 28), V( 87), V(18), V(-3), V(-14), V(-11) },
-    { V(-5), V( 22), V( 75), V(14), V( 2), V( -5), V(-19) }
+    { V( 89), V(107), V(123), V(93), V(57), V( 45), V( 51) },
+    { V( 44), V(-18), V(123), V(46), V(39), V( -7), V( 23) },
+    { V(  4), V( 52), V(162), V(37), V( 7), V(-14), V( -2) },
+    { V(-10), V(-14), V( 90), V(15), V( 2), V( -7), V(-16) }
   };
 
   // Danger of blocked enemy pawns storming our king, by rank
   constexpr Value BlockedStorm[RANK_NB] =
-    { V(0), V(0), V( 81), V(-9), V(-5), V(-1), V(26) };
+    { V(0), V(0), V(66), V(6), V(5), V(1), V(15) };
 
   #undef S
   #undef V
@@ -118,7 +118,6 @@ namespace {
         // which could become passed after one or two pawn pushes when are
         // not attacked more times than defended.
         if (   !(stoppers ^ lever ^ leverPush)
-            && !(ourPawns & forward_file_bb(Us, s))
             && popcount(supported) >= popcount(lever) - 1
             && popcount(phalanx)   >= popcount(leverPush))
             e->passedPawns[Us] |= s;
@@ -208,14 +207,12 @@ Value Entry::evaluate_shelter(const Position& pos, Square ksq) {
   constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
   constexpr Bitboard  BlockRanks = (Us == WHITE ? Rank1BB | Rank2BB : Rank8BB | Rank7BB);
 
-  Bitboard b = pos.pieces(PAWN) & (forward_ranks_bb(Us, ksq) | rank_bb(ksq));
+  Bitboard b = pos.pieces(PAWN) & ~forward_ranks_bb(Them, ksq);
   Bitboard ourPawns = b & pos.pieces(Us);
   Bitboard theirPawns = b & pos.pieces(Them);
 
-  Value safety = (ourPawns & file_bb(ksq)) ? Value(5) : Value(-5);
-
-  if (shift<Down>(theirPawns) & (FileABB | FileHBB) & BlockRanks & ksq)
-      safety += Value(374);
+  Value safety = (shift<Down>(theirPawns) & (FileABB | FileHBB) & BlockRanks & ksq) ?
+                 Value(374) : Value(5);
 
   File center = std::max(FILE_B, std::min(FILE_G, file_of(ksq)));
   for (File f = File(center - 1); f <= File(center + 1); ++f)
@@ -248,7 +245,7 @@ Score Entry::do_king_safety(const Position& pos, Square ksq) {
 
   Bitboard pawns = pos.pieces(Us, PAWN);
   if (pawns)
-      while (!(DistanceRingBB[ksq][minKingPawnDistance++] & pawns)) {}
+      while (!(DistanceRingBB[ksq][++minKingPawnDistance] & pawns)) {}
 
   Value bonus = evaluate_shelter<Us>(pos, ksq);