X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=dvonn-board.c;h=5b7c106c311909b30a47d96dc7ff3c6e7ecaf418;hb=491f9bdf58e9ad5b23858e3f780a506c45e867b2;hp=b6b36e5eac7dfefcbf1e6cce6d53901a8fcd7ff8;hpb=74df2492e8c32df37d886dec4baf9344dc6b8cff;p=dvonn

diff --git a/dvonn-board.c b/dvonn-board.c
index b6b36e5..5b7c106 100644
--- a/dvonn-board.c
+++ b/dvonn-board.c
@@ -192,6 +192,17 @@ dvonn_board_next_player (dvonn_board_t *board)
 	board->player = DVONN_PLAYER_BLACK;
 }
 
+int
+dvonn_board_pass (dvonn_board_t *board)
+{
+    /* XXX: Should check here and only allow a pass if there are
+     * no legal moves. */
+
+    dvonn_board_next_player (board);
+
+    return TRUE;
+}
+
 int
 dvonn_board_place (dvonn_board_t *board,
 		   int x, int y,
@@ -228,6 +239,49 @@ dvonn_board_place (dvonn_board_t *board,
     return TRUE;
 }
 
+static void
+fill_living(dvonn_board_t *board,
+	    int living[DVONN_BOARD_X_SIZE][DVONN_BOARD_Y_SIZE],
+	    int x, int y)
+{
+    if (dvonn_board_cell_occupied (board, x, y) && ! living[x][y])
+    {
+	living[x][y] = 1;
+
+	fill_living (board, living, x - 1, y);
+	fill_living (board, living, x + 1, y);
+	fill_living (board, living, x, y - 1);
+	fill_living (board, living, x, y + 1);
+	fill_living (board, living, x + 1, y - 1);
+	fill_living (board, living, x - 1, y + 1);
+    }
+}
+
+static void
+eliminate_disconnected_stacks (dvonn_board_t *board)
+{
+    int x, y;
+    int living[DVONN_BOARD_X_SIZE][DVONN_BOARD_Y_SIZE];
+
+    for (x = 0; x < DVONN_BOARD_X_SIZE; x++)
+	for (y = 0; y < DVONN_BOARD_Y_SIZE; y++)
+	    living[x][y] = 0;
+
+    for (x = 0; x < DVONN_BOARD_X_SIZE; x++)
+	for (y = 0; y < DVONN_BOARD_Y_SIZE; y++)
+	    if (board->cells[x][y].contains_red)
+		fill_living (board, living, x, y);
+
+    for (x = 0; x < DVONN_BOARD_X_SIZE; x++)
+	for (y = 0; y < DVONN_BOARD_Y_SIZE; y++)
+	    if (dvonn_board_cell_occupied (board, x, y) &&
+		! living[x][y])
+	    {
+		board->cells[x][y].type = DVONN_CELL_EMPTY;
+		board->cells[x][y].height = 0;
+	    }
+}
+
 int
 dvonn_board_move (dvonn_board_t *board,
 		  int x1, int y1,
@@ -250,6 +304,8 @@ dvonn_board_move (dvonn_board_t *board,
     board->cells[x1][y1].height = 0;
     board->cells[x1][y1].contains_red = FALSE;
 
+    eliminate_disconnected_stacks (board);
+
     dvonn_board_next_player (board);
 
     return TRUE;