Improved King Safety values

From an SPSA-session on king safety.

STC:
ELO: 3.21 +-2.1 (95%) LOS: 99.8%
Total: 40000 W: 8181 L: 7812 D: 24007

LTC:
LLR: 2.95 (-2.94,2.94) [0.00,4.00]
Total: 47765 W: 8091 L: 7785 D: 31889

Bench: 8589262

Resolves #241

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 8e5a7f82042d7d88a22ca39f013e3b9473793e40..153e6eaeb987e5e77ba2f8dadd135b7413711ad9 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -91,7 +91,7 @@ namespace {
   // Evaluation weights, indexed by evaluation term
   enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety };
   const struct Weight { int mg, eg; } Weights[] = {
   // Evaluation weights, indexed by evaluation term
   enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety };
   const struct Weight { int mg, eg; } Weights[] = {

-    {289, 344}, {233, 201}, {221, 273}, {46, 0}, {324, 0}
+    {289, 344}, {233, 201}, {221, 273}, {46, 0}, {322, 0}

   };
 
   #define V(v) Value(v)
   };
 
   #define V(v) Value(v)


@@ -186,15 +186,15 @@ namespace {
   // index to KingDanger[].
   //
   // KingAttackWeights[PieceType] contains king attack weights by piece type
   // index to KingDanger[].
   //
   // KingAttackWeights[PieceType] contains king attack weights by piece type

-  const int KingAttackWeights[] = { 0, 0, 8, 4, 4, 1 };
+  const int KingAttackWeights[] = { 0, 0, 7, 5, 4, 1 };

 
   // Bonuses for enemy's safe checks
   const int QueenContactCheck = 89;
 
   // Bonuses for enemy's safe checks
   const int QueenContactCheck = 89;

-  const int RookContactCheck  = 72;
-  const int QueenCheck        = 51;
-  const int RookCheck         = 38;
-  const int BishopCheck       = 5;
-  const int KnightCheck       = 16;
+  const int RookContactCheck  = 71;
+  const int QueenCheck        = 50;
+  const int RookCheck         = 37;
+  const int BishopCheck       = 6;
+  const int KnightCheck       = 14;

 
   // KingDanger[attackUnits] contains the actual king danger weighted
   // scores, indexed by a calculated integer number.
 
   // KingDanger[attackUnits] contains the actual king danger weighted
   // scores, indexed by a calculated integer number.


@@ -412,10 +412,10 @@ namespace {
         // attacked and undefended squares around our king and the quality of
         // the pawn shelter (current 'score' value).
         attackUnits =  std::min(74, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them])
         // attacked and undefended squares around our king and the quality of
         // the pawn shelter (current 'score' value).
         attackUnits =  std::min(74, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them])

-                     + 9 * ei.kingAdjacentZoneAttacksCount[Them]
+                     + 8 * ei.kingAdjacentZoneAttacksCount[Them]

                      + 25 * popcount<Max15>(undefended)
                      + 25 * popcount<Max15>(undefended)

-                     +  10 * (ei.pinnedPieces[Us] != 0)
-                     - mg_value(score) / 8
+                     +  11 * (ei.pinnedPieces[Us] != 0)
+                     - mg_value(score) * 31 / 256

                      - !pos.count<QUEEN>(Them) * 60;
 
         // Analyse the enemy's safe queen contact checks. Firstly, find the
                      - !pos.count<QUEEN>(Them) * 60;
 
         // Analyse the enemy's safe queen contact checks. Firstly, find the


@@ -891,7 +891,7 @@ namespace Eval {
 
   void init() {
 
 
   void init() {
 

-    const double MaxSlope = 8.5;
+    const double MaxSlope = 8.7;

     const double Peak = 1280;
     double t = 0.0;
 
     const double Peak = 1280;
     double t = 0.0;
 

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 032b637e6a7680408ea039d4a591bc9cc2f417e0..ef456307cafbacb4479a53627a7a1d7b58aa362d 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -63,33 +63,33 @@ namespace {
 
   // Weakness of our pawn shelter in front of the king by [distance from edge][rank]
   const Value ShelterWeakness[][RANK_NB] = {
 
   // Weakness of our pawn shelter in front of the king by [distance from edge][rank]
   const Value ShelterWeakness[][RANK_NB] = {

-  { V( 99), V(23), V(24), V(54), V(85), V( 93), V(107) },
-  { V(119), V( 2), V(28), V(72), V(96), V(104), V(114) },
-  { V(103), V( 6), V(47), V(74), V(84), V(103), V( 94) },
-  { V( 78), V(10), V(41), V(64), V(88), V( 92), V(115) } };
+  { V( 99), V(20), V(26), V(54), V(85), V( 92), V(108) },
+  { V(117), V( 1), V(27), V(71), V(94), V(104), V(118) },
+  { V(104), V( 4), V(51), V(76), V(82), V(102), V( 97) },
+  { V( 80), V(12), V(43), V(65), V(88), V( 91), V(115) } };

 
   // Danger of enemy pawns moving toward our king by [type][distance from edge][rank]
   const Value StormDanger[][4][RANK_NB] = {
 
   // Danger of enemy pawns moving toward our king by [type][distance from edge][rank]
   const Value StormDanger[][4][RANK_NB] = {

-  { { V( 0),  V(  65), V( 125), V(37), V(30) },
-    { V( 0),  V(  57), V( 136), V(39), V(24) },
-    { V( 0),  V(  50), V( 114), V(45), V(29) },
-    { V( 0),  V(  58), V( 129), V(56), V(34) } },
-  { { V(20),  V(  45), V(  91), V(47), V(20) },
-    { V(25),  V(  23), V( 105), V(38), V(14) },
-    { V(21),  V(  37), V(  99), V(35), V(21) },
-    { V(30),  V(  18), V( 105), V(38), V(28) } },
-  { { V( 0),  V(   0), V(  81), V(13), V( 4) },
-    { V( 0),  V(   0), V( 169), V(30), V( 4) },
-    { V( 0),  V(   0), V( 166), V(24), V( 6) },
-    { V( 0),  V(   0), V( 164), V(24), V(11) } },
-  { { V( 0),  V(-289), V(-297), V(57), V(29) },
-    { V( 0),  V(  66), V( 136), V(43), V(16) },
-    { V( 0),  V(  66), V( 141), V(50), V(31) },
-    { V( 0),  V(  63), V( 126), V(52), V(23) } } };
+  { { V( 0),  V(  65), V( 126), V(36), V(30) },
+    { V( 0),  V(  55), V( 135), V(36), V(23) },
+    { V( 0),  V(  47), V( 116), V(45), V(26) },
+    { V( 0),  V(  62), V( 127), V(57), V(34) } },
+  { { V(21),  V(  45), V(  93), V(50), V(19) },
+    { V(23),  V(  24), V( 105), V(41), V(13) },
+    { V(23),  V(  36), V( 101), V(38), V(20) },
+    { V(30),  V(  19), V( 110), V(41), V(27) } },
+  { { V( 0),  V(   0), V(  81), V(14), V( 4) },
+    { V( 0),  V(   0), V( 169), V(30), V( 3) },
+    { V( 0),  V(   0), V( 168), V(24), V( 5) },
+    { V( 0),  V(   0), V( 162), V(26), V(10) } },
+  { { V( 0),  V(-283), V(-298), V(57), V(29) },
+    { V( 0),  V(  63), V( 137), V(42), V(18) },
+    { V( 0),  V(  67), V( 145), V(49), V(33) },
+    { V( 0),  V(  62), V( 126), V(53), V(21) } } };

 
   // Max bonus for king safety. Corresponds to start position with all the pawns
   // in front of the king and no enemy pawn on the horizon.
 
   // Max bonus for king safety. Corresponds to start position with all the pawns
   // in front of the king and no enemy pawn on the horizon.

-  const Value MaxSafetyBonus = V(252);
+  const Value MaxSafetyBonus = V(258);

 
   #undef S
   #undef V
 
   #undef S
   #undef V