Let gatee disappear on capture of its gator

In holdingless Seirawan the piece behind a captured back-rank piece
now also is disappeared (and replaced by a dark square).

diff --git a/backend.c b/backend.c
index 9c4e220..f49b273 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -10799,16 +10799,21 @@ ApplyMove (int fromX, int fromY, int toX, int toY, int promoChar, Board board)
       }
     }
 
-    if(gameInfo.variant == VariantSChess && promoChar != NULLCHAR && promoChar != '=' && piece != WhitePawn && piece != BlackPawn) {
-       int file = fromX, white = (piece < BlackPawn);
-       if(!gameInfo.holdingsSize) {
-           int rank = fromY-2*white+1;
-           if(rank >= 0 && rank < BOARD_HEIGHT) {
-               if(board[rank][file] == DarkSquare) file = (toX > fromX ? BOARD_RGHT -1 : BOARD_LEFT); // must be castling
-               board[rank][file] = DarkSquare;
-           }
+    if(gameInfo.variant == VariantSChess) {
+      int file = fromX, white = (piece < BlackPawn);
+      int rank = fromY-2*white+1;
+      if(promoChar != NULLCHAR && promoChar != '=' && piece != WhitePawn && piece != BlackPawn) {
+       if(!gameInfo.holdingsSize && rank >= 0 && rank < BOARD_HEIGHT) {
+         if(board[rank][file] == DarkSquare) file = (toX > fromX ? BOARD_RGHT -1 : BOARD_LEFT); // must be castling
+         board[rank][file] = DarkSquare;
        }
         board[fromY][file] = CharToPiece(piece < BlackPawn ? ToUpper(promoChar) : ToLower(promoChar)); // S-Chess gating
+      }
+      if(!gameInfo.holdingsSize) {
+       rank = toY+2*white-1;
+       if(captured != EmptySquare && (rank == 0 || rank == BOARD_HEIGHT-1))
+         board[rank][toX] = DarkSquare; // gateable piece disappears with its gator
+      }
     } else
     if(promoChar == '+') {
         /* [HGM] Shogi-style promotions, to piece implied by original (Might overwrite ordinary Pawn promotion) */