diff --git a/src/mills.cpp b/src/mills.cpp
index ba52f360..add3418e 100644
--- a/src/mills.cpp
+++ b/src/mills.cpp
@@ -378,12 +378,12 @@ void move_priority_list_shuffle()
     std::array<Square, 4> movePriorityList2;
     std::array<Square, 8> movePriorityList3;
 
-    if (rule.piecesCount == 9) {
+    if (!rule.hasDiagonalLines) {
         movePriorityList0 = { SQ_16, SQ_18, SQ_20, SQ_22 };
         movePriorityList1 = { SQ_24, SQ_26, SQ_28, SQ_30, SQ_8, SQ_10, SQ_12, SQ_14 };
         movePriorityList2 = { SQ_17, SQ_19, SQ_21, SQ_23 };
         movePriorityList3 = { SQ_25, SQ_27, SQ_29, SQ_31, SQ_9, SQ_11, SQ_13, SQ_15 };
-    } else if (rule.piecesCount == 12) {
+    } else if (rule.hasDiagonalLines) {
         movePriorityList0 = { SQ_17, SQ_19, SQ_21, SQ_23 };
         movePriorityList1 = { SQ_25, SQ_27, SQ_29, SQ_31, SQ_9, SQ_11, SQ_13, SQ_15 };
         movePriorityList2 = { SQ_16, SQ_18, SQ_20, SQ_22 };
@@ -415,7 +415,7 @@ void move_priority_list_shuffle()
         MoveList<LEGAL>::movePriorityList[i + 16] = movePriorityList3[i];
     }
 #if 0
-    if (rule.piecesCount == 9 && gameOptions.getShufflingEnabled()) {
+    if (!rule.hasDiagonalLines && gameOptions.getShufflingEnabled()) {
         const uint32_t seed = static_cast<uint32_t>(now());
         std::shuffle(MoveList<LEGAL>::movePriorityList.begin(), MoveList<LEGAL>::movePriorityList.end(), std::default_random_engine(seed));
     }
diff --git a/src/movepick.cpp b/src/movepick.cpp
index be188c5c..b1284062 100644
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -94,7 +94,7 @@ void MovePicker::score()
 
                     if (to % 2 == 0 && theirPiecesCount == 3) {
                         cur->value += RATING_BLOCK_ONE_MILL * theirMillsCount;
-                    } else if (to % 2 == 1 && theirPiecesCount == 2 && rule.piecesCount == 12) {
+                    } else if (to % 2 == 1 && theirPiecesCount == 2 && rule.hasDiagonalLines) {
                         cur->value += RATING_BLOCK_ONE_MILL * theirMillsCount;
                     }
                 }
@@ -103,9 +103,9 @@ void MovePicker::score()
 
             //cur->value += bannedCount;  // placing phrase, place nearby ban point
 
-            // for 12 men, white 's 2nd move place star point is as important as close mill (TODO)
-            if (rule.piecesCount == 12 &&
-                pos.count<ON_BOARD>(WHITE) < 2 &&    // patch: only when white's 2nd move
+            // for 12 men's morris (has diagonal), white 2nd move place star point is as important as close mill (TODO)
+            if (rule.hasDiagonalLines &&
+                pos.count<ON_BOARD>(WHITE) < 2 &&    // patch: only when white 2nd move
                 Position::is_star_square(static_cast<Square>(m))) {
                 cur->value += RATING_STAR_SQUARE;
             }
diff --git a/src/position.cpp b/src/position.cpp
index 9ae7f52e..8df68514 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -1309,7 +1309,7 @@ bool Position::is_star_square(Square s)
 
 void Position::print_board()
 {
-    if (rule.piecesCount == 12) {
+    if (rule.hasDiagonalLines) {
         printf("\n"
                     "31 ----- 24 ----- 25\n"
                     "| \\       |      / |\n"
diff --git a/src/search.cpp b/src/search.cpp
index 551f0615..bba1ed85 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -140,7 +140,7 @@ int Thread::search()
 #if 0
     // TODO: Only NMM
     if (rootPos->piece_on_board_count(BLACK) + rootPos->piece_on_board_count(WHITE) <= 1 &&
-        rule.piecesCount == 9 && gameOptions.getShufflingEnabled()) {
+        !rule.hasDiagonalLines && gameOptions.getShufflingEnabled()) {
         const uint32_t seed = static_cast<uint32_t>(now());
         std::shuffle(MoveList<LEGAL>::movePriorityList.begin(), MoveList<LEGAL>::movePriorityList.end(), std::default_random_engine(seed));
     }