Add infrastructure for keeping track of board position

A Xiangqi board is added, with code to set it up from a FEN, convert it
to the board part of a FEN, and apply the moves from the move list to it,
keeping track of what was the last capture. The FEN for setting it up
is always taken from the "fen <FEN>" position command ('iniPos') of the
Cyclone dialect used in variant xiangqi.

diff --git a/UCI2WB.c b/UCI2WB.c
index 77cb1da..d7e9671 100644 (file)
--- a/UCI2WB.c
+++ b/UCI2WB.c
@@ -34,6 +34,7 @@ char move[2000][10], checkOptions[8192], iniPos[256], hashOpt[20], pause, ponder
 int mps, tc, inc, sTime, depth, myTime, hisTime, stm, computer = NONE, memory, oldMem=0, cores, moveNr, lastDepth, lastScore, startTime, debug;\r
 int statDepth, statScore, statNodes, statTime, currNr, size, collect, nr, sm, inex, on[500];\r
 char currMove[20], moveMap[500][10], /* for analyze mode */ canPonder[20], threadOpt[20];\r
+char board[100];  // XQ board for UCCI\r
 int unit = 1;\r
 \r
 FILE *toE, *fromE, *fromF;\r
@@ -79,6 +80,52 @@ Sync (int action)
 }\r
 \r
 void\r
+FromFEN(char *fen)\r
+{      int i=0;\r
+       while(*fen) {\r
+           char c = *fen++;\r
+           if(c >= 'A') board[i++] = c; else\r
+           if(c == '/') i++; else\r
+           if(c == ' ') break; else\r
+           while(c-- > '0' && i < 99) board[i++] = 0;\r
+           if(i >= 99) break;\r
+       }\r
+}\r
+\r
+char *\r
+ToFEN(int stm)\r
+{\r
+       int i, n=0; static char fen[200]; char *p = fen;\r
+       for(i=0; i<99; i++) {\r
+           char c = board[i];\r
+           if(c >= 'A')  { if(n) *p++ = '0' + n; n = 0;  *p++ = c; } else n ++;\r
+           if(i%10 == 8) { if(n) *p++ = '0' + n; n = -1; *p++ = '/'; }\r
+       }\r
+       sprintf(p-1, " %c - - 0 1", stm);\r
+       return fen;\r
+}\r
+\r
+int\r
+Sqr(char *m, int j)\r
+{\r
+       int n = m[j] - 'a' + 10*('9' - m[j+1]);\r
+       if(n < 0) n = 0; else if(n > 99) n = 99; return n;\r
+}\r
+\r
+int\r
+Play(int nr)\r
+{\r
+       int i, last = -1;\r
+       FromFEN(iniPos + 4); // in XQ iniPos always has just "fen " prefix\r
+       for(i=0; i<nr; i++) {\r
+           int from=Sqr(move[i], 0), to=Sqr(move[i], 2);\r
+           if(board[to]) last = i;\r
+           board[to] = board[from]; board[from] = 0;\r
+       }\r
+       return last;\r
+}\r
+\r
+void\r
 StartSearch(char *ponder)\r
 {      // send the 'go' command to engine. Suffix by ponder.\r
        int x = (ponder[0] != 0);\r