Tuning classical and NNUE scaling terms

FauziAkram · vondele · commit c25d4c4887db · 2022-04-16T08:41:51.000+02:00
changes to parameters in both classical and NNUE scaling, following up from an earlier successful #3958 passed STC: LLR: 2.95 (-2.94,2.94) <0.00,2.50> Total: 23936 W: 6490 L: 6234 D: 11212 Ptnml(0-2): 107, 2610, 6306, 2810, 135 https://tests.stockfishchess.org/tests/view/625820aa33c40bb9d964e6ae passed LTC: LLR: 2.94 (-2.94,2.94) <0.50,3.00> Total: 50376 W: 13629 L: 13327 D: 23420 Ptnml(0-2): 20, 4979, 14920, 5217, 52 https://tests.stockfishchess.org/tests/view/62584592c1d7f5008a33a4d1 closes #3982 Bench: 6964954
diff --git a/src/evaluate.cpp b/src/evaluate.cpp
@@ -198,12 +198,12 @@ namespace {
   constexpr Value SpaceThreshold    =  Value(11551);
 
   // KingAttackWeights[PieceType] contains king attack weights by piece type
-  constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
+  constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 76, 46, 45, 14 };
 
   // SafeCheck[PieceType][single/multiple] contains safe check bonus by piece type,
   // higher if multiple safe checks are possible for that piece type.
   constexpr int SafeCheck[][2] = {
-      {}, {}, {803, 1292}, {639, 974}, {1087, 1878}, {759, 1132}
+      {}, {}, {805, 1292}, {650, 984}, {1071, 1886}, {730, 1128}
   };
 
 #define S(mg, eg) make_score(mg, eg)
@@ -1089,7 +1089,7 @@ Value Eval::evaluate(const Position& pos) {
   // but we switch to NNUE during long shuffling or with high material on the board.
   if (  !useNNUE
       || ((pos.this_thread()->depth > 9 || pos.count<ALL_PIECES>() > 7) &&
-          abs(eg_value(pos.psq_score())) * 5 > (856 + pos.non_pawn_material() / 64) * (5 + pos.rule50_count())))
+          abs(eg_value(pos.psq_score())) * 5 > (856 + pos.non_pawn_material() / 64) * (10 + pos.rule50_count())))
   {
       v = Evaluation<NO_TRACE>(pos).value();          // classical
       useClassical = abs(v) >= 297;
@@ -1099,7 +1099,7 @@ Value Eval::evaluate(const Position& pos) {
   if (useNNUE && !useClassical)
   {
        Value nnue     = NNUE::evaluate(pos, true);     // NNUE
-       int scale      = 1036 + 20 * pos.non_pawn_material() / 1024;
+       int scale      = 1036 + 22 * pos.non_pawn_material() / 1024;
        Color stm      = pos.side_to_move();
        Value optimism = pos.this_thread()->optimism[stm];
        Value psq      = (stm == WHITE ? 1 : -1) * eg_value(pos.psq_score());
@@ -1113,7 +1113,7 @@ Value Eval::evaluate(const Position& pos) {
   }
 
   // Damp down the evaluation linearly when shuffling
-  v = v * (207 - pos.rule50_count()) / 207;
+  v = v * (195 - pos.rule50_count()) / 211;
 
   // Guarantee evaluation does not hit the tablebase range
   v = std::clamp(v, VALUE_TB_LOSS_IN_MAX_PLY + 1, VALUE_TB_WIN_IN_MAX_PLY - 1);
diff --git a/src/pawns.cpp b/src/pawns.cpp
@@ -32,48 +32,48 @@ namespace {
   #define S(mg, eg) make_score(mg, eg)
 
   // Pawn penalties
-  constexpr Score Backward      = S( 9, 22);
-  constexpr Score Doubled       = S(13, 51);
-  constexpr Score DoubledEarly  = S(20,  7);
-  constexpr Score Isolated      = S( 3, 15);
-  constexpr Score WeakLever     = S( 4, 58);
-  constexpr Score WeakUnopposed = S(13, 24);
+  constexpr Score Backward      = S( 6, 19);
+  constexpr Score Doubled       = S(11, 51);
+  constexpr Score DoubledEarly  = S(17,  7);
+  constexpr Score Isolated      = S( 1, 20);
+  constexpr Score WeakLever     = S( 2, 57);
+  constexpr Score WeakUnopposed = S(15, 18);
 
   // Bonus for blocked pawns at 5th or 6th rank
-  constexpr Score BlockedPawn[2] = { S(-17, -6), S(-9, 2) };
+  constexpr Score BlockedPawn[2] = { S(-19, -8), S(-7, 3) };
 
   constexpr Score BlockedStorm[RANK_NB] = {
-    S(0, 0), S(0, 0), S(75, 78), S(-8, 16), S(-6, 10), S(-6, 6), S(0, 2)
+    S(0, 0), S(0, 0), S(64, 75), S(-3, 14), S(-12, 19), S(-7, 4), S(-10, 5)
   };
 
   // Connected pawn bonus
-  constexpr int Connected[RANK_NB] = { 0, 5, 7, 11, 23, 48, 87 };
+  constexpr int Connected[RANK_NB] = { 0, 3, 7, 7, 15, 54, 86 };
 
   // 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( -5), V( 82), V( 92), V( 54), V( 36), V( 22), V(  28) },
-    { V(-44), V( 63), V( 33), V(-50), V(-30), V(-12), V( -62) },
-    { V(-11), V( 77), V( 22), V( -6), V( 31), V(  8), V( -45) },
-    { V(-39), V(-12), V(-29), V(-50), V(-43), V(-68), V(-164) }
+    { V(-2), V(85), V(95), V(53), V(39), V(23), V(25) },
+    { V(-55), V(64), V(32), V(-55), V(-30), V(-11), V(-61) },
+    { V(-11), V(75), V(19), V(-6), V(26), V(9), V(-47) },
+    { V(-41), V(-11), V(-27), V(-58), V(-42), V(-66), V(-163) }
   };
 
   // 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. Note that UnblockedStorm[0][1-2] accommodate opponent pawn
   // on edge, likely blocked by our king.
   constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
-    { V( 87), V(-288), V(-168), V( 96), V( 47), V( 44), V( 46) },
-    { V( 42), V( -25), V( 120), V( 45), V( 34), V( -9), V( 24) },
-    { V( -8), V(  51), V( 167), V( 35), V( -4), V(-16), V(-12) },
-    { V(-17), V( -13), V( 100), V(  4), V(  9), V(-16), V(-31) }
+    { V(94), V(-280), V(-170), V(90), V(59), V(47), V(53) },
+    { V(43), V(-17), V(128), V(39), V(26), V(-17), V(15) },
+    { V(-9), V(62), V(170), V(34), V(-5), V(-20), V(-11) },
+    { V(-27), V(-19), V(106), V(10), V(2), V(-13), V(-24) }
   };
 
 
   // KingOnFile[semi-open Us][semi-open Them] contains bonuses/penalties
   // for king when the king is on a semi-open or open file.
-  constexpr Score KingOnFile[2][2] = {{ S(-21,10), S(-7, 1)  },
-                                     {  S(  0,-3), S( 9,-4) }};
+  constexpr Score KingOnFile[2][2] = {{ S(-18,11), S(-6,-3)  },
+                                     {  S(  0, 0), S( 5,-4) }};
 
   #undef S
   #undef V
