Add final piece count to search criteria

[xboard.git] / backend.c

diff --git a/backend.c b/backend.c
index f05359c..c81e0fd 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -12364,12 +12364,26 @@ QuickCompare (Board board, int *minCounts, int *maxCounts)
 int
 QuickScan (Board board, Move *move)
 {   // reconstruct game,and compare all positions in it
-    int cnt=0, stretch=0, total = MakePieceList(board, counts);
+    int cnt=0, stretch=0, found = -1, total = MakePieceList(board, counts);
     do {
        int piece = move->piece;
        int to = move->to, from = pieceList[piece];
+       if(!found) { // if already found just scan to game end for final piece count
+         if(QuickCompare(soughtBoard, minSought, maxSought) ||
+          appData.ignoreColors && QuickCompare(reverseBoard, minReverse, maxReverse) ||
+          flipSearch && (QuickCompare(flipBoard, minSought, maxSought) ||
+                               appData.ignoreColors && QuickCompare(rotateBoard, minReverse, maxReverse))
+           ) {
+           static int lastCounts[EmptySquare+1];
+           int i;
+           if(stretch) for(i=0; i<EmptySquare; i++) if(lastCounts[i] != counts[i]) { stretch = 0; break; } // reset if material changes
+           if(stretch++ == 0) for(i=0; i<EmptySquare; i++) lastCounts[i] = counts[i]; // remember actual material
+         } else stretch = 0;
+         if(stretch && (appData.searchMode == 1 || stretch >= appData.stretch)) found = cnt + 1 - stretch;
+         if(found && !appData.minPieces) return found;
+       }
        if(piece <= Q_PROMO) { // special moves encoded by otherwise invalid piece numbers 1-4
-         if(!piece) return -1;
+         if(!piece) return (appData.minPieces && (total < appData.minPieces || total > appData.maxPieces) ? -1 : found);
          if(piece == Q_PROMO) { // promotion, encoded as (Q_PROMO, to) + (piece, promoType)
            piece = (++move)->piece;
            from = pieceList[piece];
@@ -12400,17 +12414,6 @@ QuickScan (Board board, Move *move)
        quickBoard[to] = piece;
        pieceList[piece] = to;
        cnt++; turn ^= 3;
-       if(QuickCompare(soughtBoard, minSought, maxSought) ||
-          appData.ignoreColors && QuickCompare(reverseBoard, minReverse, maxReverse) ||
-          flipSearch && (QuickCompare(flipBoard, minSought, maxSought) ||
-                               appData.ignoreColors && QuickCompare(rotateBoard, minReverse, maxReverse))
-         ) {
-           static int lastCounts[EmptySquare+1];
-           int i;
-           if(stretch) for(i=0; i<EmptySquare; i++) if(lastCounts[i] != counts[i]) { stretch = 0; break; } // reset if material changes
-           if(stretch++ == 0) for(i=0; i<EmptySquare; i++) lastCounts[i] = counts[i]; // remember actual material
-       } else stretch = 0;
-       if(stretch && (appData.searchMode == 1 || stretch >= appData.stretch)) return cnt + 1 - stretch;
        move++;
     } while(1);
 }