X-Git-Url: http://git.draconx.ca/gitweb/rrace.git/blobdiff_plain/2529a9651d160ab3a17118d778f5e5584d040765..b39d19918b63b80d1f3b068d158fe43415b9d1b6:/src/game.h

diff --git a/src/game.h b/src/game.h
index f4473a7..301dfac 100644
--- a/src/game.h
+++ b/src/game.h
@@ -42,11 +42,12 @@ struct board {
 	 * corresponds to position (0,0), bit 4 is position (4,0) and bit 25
 	 * is position (4, 4).
 	 *
-	 *   game[0] - the board mask, all bits set except one indicating the
-	 *             absense of a tile at this position.
-	 *   game[1] - least significant bit of the tile's colour.
-	 *   game[2] - tile colour.
-	 *   game[3] - most significant bit of the tile's colour.
+	 *   game[0] - least significant bit of the tile's colour.
+	 *   game[1] - tile colour.
+	 *   game[2] - most significant bit of the tile's colour.
+	 *   game[3] - No internal meaning.  The game_reset function will clear
+	 *             the bit at the empty position and set all others, and
+	 *             game_do_move will adjust it.
 	 */
 	uint_least32_t game[4];
 
@@ -110,6 +111,46 @@ static inline uint_fast32_t board_mask_v(int x, int y0, int y1)
 	return (col << 5*y1) & (col >> 5*(4-y0));
 }
 
+/*
+ * Return the board bitmap setting locations on or above row y.
+ */
+static inline uint_fast32_t board_above(int y)
+{
+	uint_fast32_t val = board_row(y);
+
+	return val | (val-1);
+}
+
+/*
+ * Return the board bitmap setting locations on or below row y.
+ */
+static inline uint_fast32_t board_below(int y)
+{
+	uint_fast32_t val = board_row(y);
+
+	return val | (~val + 1);
+}
+
+/*
+ * Return the board bitmap setting locations on or left of column x.
+ */
+static inline uint_fast32_t board_left(int x)
+{
+	uint_fast32_t val = board_column(x);
+
+	return val | (val - 0x108421);
+}
+
+/*
+ * Return the board bitmap setting locations on or right of column x.
+ */
+static inline uint_fast32_t board_right(int x)
+{
+	uint_fast32_t val = board_column(x);
+
+	return ~val + 0x108421;
+}
+
 /*
  * Move the bits in the game bitmaps according to a move at position (x, y),
  * and update the location of the empty position which, if the move was valid
@@ -119,6 +160,11 @@ static inline uint_fast32_t board_mask_v(int x, int y0, int y1)
  */
 int game_do_move(struct board *board, int x, int y);
 
+/*
+ * Returns 1 if the game is in a winning position, or 0 otherwise.
+ */
+int game_check_goal(struct board *board);
+
 /*
  * Initialize the game RNG such that the next call to game_reset will produce a
  * new board that is entirely dependent on the given seed value.
@@ -130,4 +176,9 @@ void game_reseed(unsigned long long seed);
  */
 void game_reset(struct board *board);
 
+/*
+ * Disable new moves and clear all tile bits other than the 9 goal tiles.
+ */
+void game_finish(struct board *board);
+
 #endif