evaluate: MOBILITY: Modify implement (WIP)

No improvement now.
Keep Disabling it.

include/config.h

@@ -25,6 +25,8 @@
 #pragma execution_character_set("utf-8")
 #endif
 
+//#define EVALUATE_MOBILITY
+
 //#undef QT_GUI_LIB
 
 //#define UCI_AUTO_RE_GO

src/evaluate.cpp

@@ -87,10 +87,7 @@ Value Evaluation::value()
         value = (pos.piece_on_board_count(BLACK) - pos.piece_on_board_count(WHITE)) * VALUE_EACH_PIECE_ONBOARD;
 
 #ifdef EVALUATE_MOBILITY
-        value += pos.get_mobility_diff(position->turn, 
-                                       position->pieceInHandCount[BLACK],
-                                       position->pieceInHandCount[WHITE], 
-                                       false) * 10;
+        value += pos.get_mobility_diff() / 5;
 #endif  /* EVALUATE_MOBILITY */
 
         switch (pos.get_action()) {

src/position.cpp

@@ -1018,27 +1018,30 @@ bool Position::check_if_game_is_over()
     return false;
 }
 
-int Position::get_mobility_diff(bool includeBanned)
+int Position::get_mobility_diff()
 {
     // TODO: Deal with rule is no ban location
     int mobilityBlack = 0;
     int mobilityWhite = 0;
-    int diff = 0;
-    int n = 0;
 
-    for (Square i = SQ_BEGIN; i < SQ_END; ++i) {
-        n = surrounded_empty_squares_count(i, includeBanned);
-
-        if (board[i] & B_STONE) {
-            mobilityBlack += n;
-        } else if (board[i] & W_STONE) {
-            mobilityWhite += n;
-        }
+    for (Square s = SQ_BEGIN; s < SQ_END; ++s) {
+        if (board[s] == NO_PIECE || board[s] == BAN_STONE) {
+            Square moveSquare;
+            for (MoveDirection d = MD_BEGIN; d < MD_NB; ++d) {
+                moveSquare = static_cast<Square>(MoveList<LEGAL>::adjacentSquares[s][d]);
+                if (moveSquare) {
+                    if (board[moveSquare] & B_STONE) {
+                        mobilityBlack++;
+                    }
+                    if (board[moveSquare] & W_STONE) {
+                        mobilityWhite++;
+                    }
+                }
+            }
+        } 
     }
 
-    diff = mobilityBlack - mobilityWhite;
-
-    return diff;
+    return mobilityBlack - mobilityWhite;
 }
 
 void Position::remove_ban_stones()
@@ -1236,30 +1239,6 @@ bool Position::is_all_in_mills(Color c)
     return true;
 }
 
-// Stat include ban
-int Position::surrounded_empty_squares_count(Square s, bool includeBanned)
-{
-    //assert(rule.hasBannedLocations == includeBanned);
-
-    int n = 0;
-
-    if (pieceOnBoardCount[sideToMove] > rule.piecesAtLeastCount ||
-        !rule.mayFly) {
-        Square moveSquare;
-        for (MoveDirection d = MD_BEGIN; d < MD_NB; ++d) {
-            moveSquare = static_cast<Square>(MoveList<LEGAL>::adjacentSquares[s][d]);
-            if (moveSquare) {
-                if (board[moveSquare] == 0x00 ||
-                    (includeBanned && board[moveSquare] == BAN_STONE)) {
-                    n++;
-                }
-            }
-        }
-    }
-
-    return n;
-}
-
 void Position::surrounded_pieces_count(Square s, int &ourPieceCount, int &theirPieceCount, int &bannedCount, int &emptyCount)
 {
     Square moveSquare;

src/position.h

@@ -105,7 +105,7 @@ public:
     enum Action get_action() const;
     const char *get_record() const;
 
-    int get_mobility_diff(bool includeBanned);
+    int get_mobility_diff();
 
     bool reset();
     bool start();
@@ -133,7 +133,6 @@ public:
     int potential_mills_count(Square to, Color c, Square from = SQ_0);
     bool is_all_in_mills(Color c);
 
-    int surrounded_empty_squares_count(Square s, bool includeBanned);
     void surrounded_pieces_count(Square s, int &nOurPieces, int &nTheirPieces, int &nBanned, int &nEmpty);
     bool is_all_surrounded(Color c, Square from = SQ_0, Square to = SQ_0) const;