Report changed positions from game_do_move.

[rrace.git] / src / game.h

diff --git a/src/game.h b/src/game.h
index a734e229058f5182f96c28c3512c19c06fec6965..176cb367a51e18671a5a8315961a0cda92658bb2 100644 (file)
--- a/src/game.h
+++ b/src/game.h
@@ -161,9 +161,10 @@ static inline uint_fast32_t board_right(int x)
  * 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 the board bitmap setting game locations that differ from the goal.