Improve identification of e.p. victim

[xboard.git] / moves.c

diff --git a/moves.c b/moves.c
index 91f0072..876564c 100644 (file)
--- a/moves.c
+++ b/moves.c
@@ -809,9 +809,10 @@ GenPseudoLegal (Board board, int flags, MoveCallback callback, VOIDSTAR closure,
                               rf, ff, rf + 1, ff + s, closure);
                  }
                  if (rf >= BOARD_HEIGHT+1>>1) {// [HGM] grand: 4th & 5th rank on 10-board
+                     int victimFile = (board[LAST_FILE] == 100 ? ff + s : board[LAST_FILE]);
                       if (ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
-                         (epfile == ff + s || epfile == EP_UNKNOWN) && rf < BOARD_HEIGHT-3 &&
-                          board[rf][ff + s] == BlackPawn &&
+                         (board[EP_FILE] == ff + s || epfile == EP_UNKNOWN) && rf < BOARD_HEIGHT-3 &&
+                          (board[rf][victimFile] == BlackPawn || board[rf][victimFile] == BlackLance) &&
                           board[rf+1][ff + s] == EmptySquare) {
                          callback(board, flags, WhiteCapturesEnPassant,
                                   rf, ff, rf+1, ff + s, closure);
@@ -859,9 +860,10 @@ GenPseudoLegal (Board board, int flags, MoveCallback callback, VOIDSTAR closure,
                               rf, ff, rf - 1, ff + s, closure);
                  }
                  if (rf < BOARD_HEIGHT>>1) {
+                     int victimFile = (board[LAST_FILE] == 100 ? ff + s : board[LAST_FILE]);
                       if (ff + s >= BOARD_LEFT && ff + s < BOARD_RGHT &&
-                         (epfile == ff + s || epfile == EP_UNKNOWN) && rf > 2 &&
-                         board[rf][ff + s] == WhitePawn &&
+                         (board[EP_FILE] == ff + s || epfile == EP_UNKNOWN) && rf > 2 &&
+                         (board[rf][victimFile] == WhitePawn || board[rf][victimFile] == WhiteLance) &&
                          board[rf-1][ff + s] == EmptySquare) {
                          callback(board, flags, BlackCapturesEnPassant,
                                   rf, ff, rf-1, ff + s, closure);
@@ -1735,6 +1737,8 @@ CheckTest (Board board, int flags, int rf, int ff, int rt, int ft, int enPassant
        }
     }
 
+    if(PieceToChar(king) == '.') return 0; // never in check if the royal piece does not participate
+
     if (rt >= 0) {
        if (enPassant) {
            captured = board[rf][ft];
@@ -2163,6 +2167,11 @@ Disambiguate (Board board, int flags, DisambiguateClosure *closure)
        }
     } else if(pieceDefs && closure->count > 1 && closure->rtIn >=0) { // [HGM] gen: move is ambiguous under engine-defined rules (and not one-click)
        DisambiguateClosure spare = *closure;
+        if(gameInfo.variant == VariantXiangqi && closure->pieceIn == EmptySquare && closure->ffIn < 0) {
+            closure->ffIn = closure->ftIn; //closure->pieceIn = (flags & 1 ? BlackPawn : WhitePawn); // forward Pawn push has priority
+            Disambiguate(board, flags, closure);
+            return;
+        }
        pieceDefs = FALSE; spare.count = 0;     // See if the (erroneous) built-in rules would resolve that
         GenLegal(board, flags, DisambiguateCallback, (VOIDSTAR) &spare, closure->pieceIn);
        if(spare.count == 1) *closure = spare;  // It does, so use those in stead (game from file saved before gen patch?)