X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=8a7fcb8dc6f7f9d53367246dfd44562c7177de35;hp=22953cff6d8d4328706cb1ffe4299d46214d2c05;hb=a3a0df92a3ed5ce7c98ff596e687d3d6533590c8;hpb=4ede49cd850392f28bc9da9537c111d2c3f0b297

diff --git a/src/material.cpp b/src/material.cpp
index 22953cff..8a7fcb8d 100644
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -39,7 +39,7 @@ namespace {
   const Value RedundantRook  = Value(554);
 
   //                                  pair  pawn knight bishop rook queen
-  const int LinearCoefficients[6] = { 1617, -162, -1172, -190,  105,  26 };
+  const int LinearCoefficients[6] = { 1817, -162, -1122, -190,  105,  26 };
 
   const int QuadraticCoefficientsSameColor[][PIECE_TYPE_NB] = {
     // pair pawn knight bishop rook queen
@@ -113,7 +113,7 @@ namespace {
                 + RedundantQueen * pieceCount[Us][QUEEN];
 
     // Second-degree polynomial material imbalance by Tord Romstad
-    for (pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++)
+    for (pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
     {
         pc = pieceCount[Us][pt1];
         if (!pc)
@@ -121,7 +121,7 @@ namespace {
 
         v = LinearCoefficients[pt1];
 
-        for (pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++)
+        for (pt2 = NO_PIECE_TYPE; pt2 <= pt1; ++pt2)
             v +=  QuadraticCoefficientsSameColor[pt1][pt2] * pieceCount[Us][pt2]
                 + QuadraticCoefficientsOppositeColor[pt1][pt2] * pieceCount[Them][pt2];
 
@@ -240,7 +240,8 @@ Entry* probe(const Position& pos, Table& entries, Endgames& endgames) {
       }
   }
 
-  // No pawns makes it difficult to win, even with a material advantage
+  // No pawns makes it difficult to win, even with a material advantage. This
+  // catches some trivial draws like KK, KBK and KNK
   if (!pos.count<PAWN>(WHITE) && npm_w - npm_b <= BishopValueMg)
   {
       e->factor[WHITE] = (uint8_t)
@@ -259,7 +260,7 @@ Entry* probe(const Position& pos, Table& entries, Endgames& endgames) {
       int minorPieceCount =  pos.count<KNIGHT>(WHITE) + pos.count<BISHOP>(WHITE)
                            + pos.count<KNIGHT>(BLACK) + pos.count<BISHOP>(BLACK);
 
-      e->spaceWeight = minorPieceCount * minorPieceCount;
+      e->spaceWeight = make_score(minorPieceCount * minorPieceCount, 0);
   }
 
   // Evaluate the material imbalance. We use PIECE_TYPE_NONE as a place holder