Castle with nearest rather than corner piece

[xboard.git] / backend.c

diff --git a/backend.c b/backend.c
index be8956f..670eb4b 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -8667,12 +8667,13 @@ FakeBookMove: // [HGM] book: we jump here to simulate machine moves after book h
            safeStrCpy(firstLeg, machineMove, 20); // just remember it for processing when second leg arrives
            return;
        } else if(firstLeg[0]) { // there was a previous leg;
-           // only support case where same piece makes two step (and don't even test that!)
+           // only support case where same piece makes two step
            char buf[20], *p = machineMove+1, *q = buf+1, f;
            safeStrCpy(buf, machineMove, 20);
            while(isdigit(*q)) q++; // find start of to-square
            safeStrCpy(machineMove, firstLeg, 20);
-           while(isdigit(*p)) p++;
+           while(isdigit(*p)) p++; // to-square of first leg (which is now copied to machineMove)
+           if(*p == *buf)          // if first-leg to not equal to second-leg from first leg says unmodified (assume it ia King move of castling)
            safeStrCpy(p, q, 20); // glue to-square of second leg to from-square of first, to process over-all move
            sscanf(buf, "%c%d", &f, &killY); killX = f - AAA; killY -= ONE - '0'; // pass intermediate square to MakeMove in global
            firstLeg[0] = NULLCHAR;
@@ -10010,8 +10011,8 @@ ApplyMove (int fromX, int fromY, int toX, int toY, int promoChar, Board board)
      if(gameInfo.variant == VariantKnightmate)
          king += (int) WhiteUnicorn - (int) WhiteKing;
 
-    if(piece != WhiteKing && piece != BlackKing && pieceDesc[piece] && killX >= 0 && strchr(pieceDesc[piece], 'O') // Betza castling-enabled
-       && (piece < BlackPawn ? killed < BlackPawn : killed >= BlackPawn)) {    // and captures own
+    if(pieceDesc[piece] && killX >= 0 && strchr(pieceDesc[piece], 'O') // Betza castling-enabled
+       && (piece < BlackPawn ? killed < BlackPawn : killed >= BlackPawn)) {    // and tramples own
        board[toY][toX] = piece; board[fromY][fromX] = EmptySquare;
        board[toY][toX + (killX < fromX ? 1 : -1)] = killed;
         board[EP_STATUS] = EP_NONE; // capture was fake!
@@ -10043,19 +10044,19 @@ ApplyMove (int fromX, int fromY, int toX, int toY, int promoChar, Board board)
     } else if (board[fromY][fromX] == king
         && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1 // [HGM] cylinder */
         && toY == fromY && toX > fromX+1) {
+       for(rookX=fromX+1; board[toY][rookX] == EmptySquare && rookX < BOARD_RGHT-1; rookX++); // castle with nearest piece
+        board[fromY][toX-1] = board[fromY][rookX];
+        board[fromY][rookX] = EmptySquare;
        board[fromY][fromX] = EmptySquare;
         board[toY][toX] = king;
-       for(rookX=BOARD_RGHT-1; board[toY][rookX] == DarkSquare && rookX > toX + 1; rookX--);
-        board[toY][toX-1] = board[fromY][rookX];
-        board[fromY][rookX] = EmptySquare;
     } else if (board[fromY][fromX] == king
         && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1 // [HGM] cylinder */
                && toY == fromY && toX < fromX-1) {
+       for(rookX=fromX-1; board[toY][rookX] == EmptySquare && rookX > 0; rookX--); // castle with nearest piece
+        board[fromY][toX+1] = board[fromY][rookX];
+        board[fromY][rookX] = EmptySquare;
        board[fromY][fromX] = EmptySquare;
         board[toY][toX] = king;
-       for(rookX=BOARD_LEFT; board[toY][rookX] == DarkSquare && rookX < toX - 1; rookX++);
-        board[toY][toX+1] = board[fromY][rookX];
-        board[fromY][rookX] = EmptySquare;
     } else if ((board[fromY][fromX] == WhitePawn && gameInfo.variant != VariantXiangqi ||
                 board[fromY][fromX] == WhiteLance && gameInfo.variant != VariantSuper && gameInfo.variant != VariantChu)
                && toY >= BOARD_HEIGHT-promoRank && promoChar // defaulting to Q is done elsewhere
@@ -10094,19 +10095,19 @@ ApplyMove (int fromX, int fromY, int toX, int toY, int promoChar, Board board)
     } else if (board[fromY][fromX] == king
         && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1 // [HGM] cylinder */
                && toY == fromY && toX > fromX+1) {
+       for(rookX=toX+1; board[toY][rookX] == EmptySquare && rookX < BOARD_RGHT - 1; rookX++);
+        board[fromY][toX-1] = board[fromY][rookX];
+        board[fromY][rookX] = EmptySquare;
        board[fromY][fromX] = EmptySquare;
         board[toY][toX] = king;
-       for(rookX=BOARD_RGHT-1; board[toY][rookX] == DarkSquare && rookX > toX + 1; rookX--);
-        board[toY][toX-1] = board[fromY][rookX];
-        board[fromY][rookX] = EmptySquare;
     } else if (board[fromY][fromX] == king
         && fromX != BOARD_LEFT && fromX != BOARD_RGHT-1 // [HGM] cylinder */
                && toY == fromY && toX < fromX-1) {
+       for(rookX=toX-1; board[toY][rookX] == EmptySquare && rookX > 0; rookX--);
+        board[fromY][toX+1] = board[fromY][rookX];
+        board[fromY][rookX] = EmptySquare;
        board[fromY][fromX] = EmptySquare;
         board[toY][toX] = king;
-       for(rookX=BOARD_LEFT; board[toY][rookX] == DarkSquare && rookX < toX - 1; rookX++);
-        board[toY][toX+1] = board[fromY][rookX];
-        board[fromY][rookX] = EmptySquare;
     } else if (fromY == 7 && fromX == 3
               && board[fromY][fromX] == BlackKing
               && toY == 7 && toX == 5) {