X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;ds=sidebyside;f=src%2Fendgame.cpp;h=97274946b00c243e50852fd854b8ca8c52f25953;hb=95212222c7444538b84326208e433ac12f15e9fb;hp=0d9d3c26c216b2fbeb394b5a887c21530ac90425;hpb=4f3fe89fb6e957fd971a76080687ba358ec27603;p=stockfish

diff --git a/src/endgame.cpp b/src/endgame.cpp
index 0d9d3c26..97274946 100644
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -26,6 +26,7 @@
 
 #include "bitcount.h"
 #include "endgame.h"
+#include "pawns.h"
 
 
 ////
@@ -155,7 +156,7 @@ Value EvaluationFunction<KBNK>::apply(const Position& pos) const {
   // kbnk_mate_table() tries to drive toward corners A1 or H8,
   // if we have a bishop that cannot reach the above squares we
   // mirror the kings so to drive enemy toward corners A8 or H1.
-  if (!same_color_squares(bishopSquare, SQ_A1))
+  if (opposite_color_squares(bishopSquare, SQ_A1))
   {
       winnerKSq = flop_square(winnerKSq);
       loserKSq = flop_square(loserKSq);
@@ -401,8 +402,8 @@ ScaleFactor ScalingFunction<KBPsK>::apply(const Position& pos) const {
       Square queeningSq = relative_square(strongerSide, make_square(pawnFile, RANK_8));
       Square kingSq = pos.king_square(weakerSide);
 
-      if (  !same_color_squares(queeningSq, bishopSq)
-          && file_distance(square_file(kingSq), pawnFile) <= 1)
+      if (   opposite_color_squares(queeningSq, bishopSq)
+          && abs(square_file(kingSq) - pawnFile) <= 1)
       {
           // The bishop has the wrong color, and the defending king is on the
           // file of the pawn(s) or the neighboring file. Find the rank of the
@@ -678,12 +679,12 @@ ScaleFactor ScalingFunction<KBPKB>::apply(const Position& pos) const {
   // Case 1: Defending king blocks the pawn, and cannot be driven away
   if (   square_file(weakerKingSq) == square_file(pawnSq)
       && relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq)
-      && (  !same_color_squares(weakerKingSq, strongerBishopSq)
+      && (   opposite_color_squares(weakerKingSq, strongerBishopSq)
           || relative_rank(strongerSide, weakerKingSq) <= RANK_6))
       return SCALE_FACTOR_ZERO;
 
   // Case 2: Opposite colored bishops
-  if (!same_color_squares(strongerBishopSq, weakerBishopSq))
+  if (opposite_color_squares(strongerBishopSq, weakerBishopSq))
   {
       // We assume that the position is drawn in the following three situations:
       //
@@ -728,8 +729,7 @@ ScaleFactor ScalingFunction<KBPPKB>::apply(const Position& pos) const {
   Square wbsq = pos.piece_list(strongerSide, BISHOP, 0);
   Square bbsq = pos.piece_list(weakerSide, BISHOP, 0);
 
-  if (same_color_squares(wbsq, bbsq))
-      // Not opposite-colored bishops, no scaling
+  if (!opposite_color_squares(wbsq, bbsq))
       return SCALE_FACTOR_NONE;
 
   Square ksq = pos.king_square(weakerSide);
@@ -757,7 +757,7 @@ ScaleFactor ScalingFunction<KBPPKB>::apply(const Position& pos) const {
     // some square in the frontmost pawn's path.
     if (   square_file(ksq) == square_file(blockSq1)
         && relative_rank(strongerSide, ksq) >= relative_rank(strongerSide, blockSq1)
-        && !same_color_squares(ksq, wbsq))
+        && opposite_color_squares(ksq, wbsq))
         return SCALE_FACTOR_ZERO;
     else
         return SCALE_FACTOR_NONE;
@@ -767,14 +767,14 @@ ScaleFactor ScalingFunction<KBPPKB>::apply(const Position& pos) const {
     // in front of the frontmost pawn's path, and the square diagonally behind
     // this square on the file of the other pawn.
     if (   ksq == blockSq1
-        && !same_color_squares(ksq, wbsq)
+        && opposite_color_squares(ksq, wbsq)
         && (   bbsq == blockSq2
             || (pos.attacks_from<BISHOP>(blockSq2) & pos.pieces(BISHOP, weakerSide))
-            || rank_distance(r1, r2) >= 2))
+            || abs(r1 - r2) >= 2))
         return SCALE_FACTOR_ZERO;
 
     else if (   ksq == blockSq2
-             && !same_color_squares(ksq, wbsq)
+             && opposite_color_squares(ksq, wbsq)
              && (   bbsq == blockSq1
                  || (pos.attacks_from<BISHOP>(blockSq1) & pos.pieces(BISHOP, weakerSide))))
         return SCALE_FACTOR_ZERO;
@@ -808,7 +808,7 @@ ScaleFactor ScalingFunction<KBPKN>::apply(const Position& pos) const {
 
   if (   square_file(weakerKingSq) == square_file(pawnSq)
       && relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq)
-      && (  !same_color_squares(weakerKingSq, strongerBishopSq)
+      && (   opposite_color_squares(weakerKingSq, strongerBishopSq)
           || relative_rank(strongerSide, weakerKingSq) <= RANK_6))
       return SCALE_FACTOR_ZERO;