Small renaming in material weights

Also dropped some temporary variable: compiler
is more than able to push on stack temp values
by itself (verified).

No functional change.

src/material.cpp

@@ -29,10 +29,10 @@ namespace {
 
   // Polynomial material balance parameters
 
-  //                                  pair  pawn knight bishop rook queen
-  const int LinearCoefficients[6] = { 1852, -162, -1122, -183,  249, -154 };
+  //                      pair  pawn knight bishop rook queen
+  const int Linear[6] = { 1852, -162, -1122, -183,  249, -154 };
 
-  const int QuadraticCoefficientsSameSide[][PIECE_TYPE_NB] = {
+  const int QuadraticSameSide[][PIECE_TYPE_NB] = {
     //            OUR PIECES
     // pair pawn knight bishop rook queen
     {   0                               }, // Bishop pair
@@ -43,7 +43,7 @@ namespace {
     {-177,   25, 129,   142,  -137,   0 }  // Queen
   };
 
-  const int QuadraticCoefficientsOppositeSide[][PIECE_TYPE_NB] = {
+  const int QuadraticOppositeSide[][PIECE_TYPE_NB] = {
     //           THEIR PIECES
     // pair pawn knight bishop rook queen
     {   0                               }, // Bishop pair
@@ -93,26 +93,24 @@ namespace {
 
     const Color Them = (Us == WHITE ? BLACK : WHITE);
 
-    int pt1, pt2, pc, v;
-    int value = 0;
+    int bonus = 0;
 
     // Second-degree polynomial material imbalance by Tord Romstad
-    for (pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
+    for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
     {
-        pc = pieceCount[Us][pt1];
-        if (!pc)
+        if (!pieceCount[Us][pt1])
             continue;
 
-        v = LinearCoefficients[pt1];
+        int v = Linear[pt1];
 
-        for (pt2 = NO_PIECE_TYPE; pt2 <= pt1; ++pt2)
-            v +=  QuadraticCoefficientsSameSide[pt1][pt2] * pieceCount[Us][pt2]
-                + QuadraticCoefficientsOppositeSide[pt1][pt2] * pieceCount[Them][pt2];
+        for (int pt2 = NO_PIECE_TYPE; pt2 <= pt1; ++pt2)
+            v +=  QuadraticSameSide[pt1][pt2] * pieceCount[Us][pt2]
+                + QuadraticOppositeSide[pt1][pt2] * pieceCount[Them][pt2];
 
-        value += pc * v;
+        bonus += pieceCount[Us][pt1] * v;
     }
 
-    return value;
+    return bonus;
   }
 
 } // namespace