Add some basic scaffolding for the game logic

game.c

@@ -0,0 +1,50 @@
+/*
+ * File: game.c
+ * Author: Jeremy Rand
+ * Date: July 23, 2014
+ *
+ * This file contains the implementation of the game logic.
+ */
+
+
+#include "game.h"
+
+
+void initGame(void)
+{
+}
+
+
+void slideInDirection(tDir dir)
+{
+}
+
+
+tScore currentScore(void)
+{
+    return 0;
+}
+
+
+tScore nextTarget(void)
+{
+    return 0;
+}
+
+
+bool isGameWon(void)
+{
+    return false;
+}
+
+
+bool isGameLost(void)
+{
+    return false;
+}
+
+
+char *tileStringForPos(tPos x, tPos y)
+{
+    return "";
+}

game.h

@@ -0,0 +1,41 @@
+/*
+ * File: game.h
+ * Author: Jeremy Rand
+ * Date: July 23, 2014
+ *
+ * This file has the external definitions for the game interface.
+ */
+
+
+#include <stdint.h>
+#include <stdbool.h>
+
+
+#define BOARD_SIZE 4
+
+#define DIR_DOWN (BOARD_SIZE + 2)
+#define DIR_UP (-(DIR_DOWN))
+#define DIR_RIGHT 1
+#define DIR_LEFT -1
+
+
+typedef int8_t tDir;
+typedef uint8_t tPos;
+typedef uint32_t tScore;
+
+
+void initGame(void);
+
+void slideInDirection(tDir dir);
+
+tScore currentScore(void);
+
+tScore nextTarget(void);
+
+bool isGameWon(void);
+
+bool isGameLost(void);
+
+// Positions are 1 based so the top-left corner is (1, 1) and the bottom-right
+// corner is (BOARD_SIZE, BOARD_SIZE).
+char *tileStringForPos(tPos x, tPos y);