Report changed positions from game_do_move.

[rrace.git] / src / game.h

diff --git a/src/game.h b/src/game.h
index d17eb992f7fd3d86d19d521b537588c4e1dbe2c5..176cb367a51e18671a5a8315961a0cda92658bb2 100644 (file)
--- a/src/game.h
+++ b/src/game.h
@@ -20,6 +20,7 @@
 #define RRACE_GAME_H_
 
 #include <inttypes.h>
+#include <xtime.h>
 
 enum {
        TILE_EMPTY,
@@ -32,7 +33,9 @@ enum {
        TILE_MAX
 };
 
-enum { GOAL_SHIFT = 6 };
+#define GOAL_SHIFT 6
+#define GOAL_MASK 0x739c0ul
+
 struct board {
        /*
         * Bit planes representing the current game area.
@@ -45,8 +48,9 @@ struct board {
         *   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] - the board mask, all bits set except one indicating the
-        *             absense of a tile at this position.
+        *   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];
 
@@ -62,8 +66,10 @@ struct board {
         */
        uint_least16_t goal[3];
 
-       /* (x, y) position of the current empty position. */
+       /* (x, y) position of the current empty space. */
        uint_least8_t x, y;
+
+       xtime_t time_start;
 };
 
 /* Return the board bitmap with all bits in column x set */
@@ -110,19 +116,61 @@ 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
  * is now (x, y).
  *
- * Returns 0 if the move was valid (and board has been updated), -1 otherwise.
+ * Returns the board bitmap indicating which positions changed.  A return
+ * value of 0 therefore indicates an invalid move.
  */
-int game_do_move(struct board *board, int x, int y);
+uint_fast32_t game_do_move(struct board *board, int x, int y);
 
 /*
- * Returns 1 if the game is in a winning position, or 0 otherwise.
+ * Returns the board bitmap setting game locations that differ from the goal.
+ * A return value of 0 therefore indicates a winning position.
  */
-int game_check_goal(struct board *board);
+uint_fast32_t game_check_goal(struct board *board);
 
 /*
  * Initialize the game RNG such that the next call to game_reset will produce a
@@ -135,9 +183,15 @@ void game_reseed(unsigned long long seed);
  */
 void game_reset(struct board *board);
 
+/*
+ * Reset the game start time.
+ */
+void game_begin(struct board *board);
+
 /*
  * Disable new moves and clear all tile bits other than the 9 goal tiles.
+ * Returns the total elapsed time (in ms).
  */
-void game_finish(struct board *board);
+int_fast32_t game_finish(struct board *board);
 
 #endif