X-Git-Url: https://plomlompom.com/repos/?a=blobdiff_plain;f=src%2Fyx_uint16.h;h=325b22449570ca6fad0a18158a8ed07768e78bc2;hb=550d22ec0c3f530f5d317746f3f7e75251a1de4b;hp=4751b683719636220275e2d4af3ac420d63ce13e;hpb=b944d403e356e444b47b0f5768406c0527151be0;p=plomrogue

diff --git a/src/yx_uint16.h b/src/yx_uint16.h
index 4751b68..325b224 100644
--- a/src/yx_uint16.h
+++ b/src/yx_uint16.h
@@ -1,18 +1,49 @@
+/* yx_uint16.h
+ *
+ * Structs and routines for coordinates and movement in 2-dimensional space
+ * (such as the ncurses screen and game maps).
+ */
+
 #ifndef YX_UINT16_H
 #define YX_UINT16_H
 
-#include <stdint.h>
 
-#define NORTH 1
-#define EAST 2
-#define SOUTH 3
-#define WEST 4
 
-struct yx_uint16 {
-  uint16_t y;
-  uint16_t x; };
+#include <stdint.h> /* for uint8_t, uint16_t */
+
+
+
+/* Coordinates for maps of max. 65536x65536 cells. */
+struct yx_uint16
+{
+    uint16_t y;
+    uint16_t x;
+};
+
+
+
+/* Directions available for movement. */
+enum dir
+{
+    NORTH = 1,
+    EAST,
+    SOUTH,
+    WEST
+};
+
+
+
+/* Return 1 if two yx_uint16 coordinates at "a" and "b" are equal, else 0. */
+extern uint8_t yx_uint16_cmp(struct yx_uint16 * a, struct yx_uint16 * b);
+
+
+
+/* Return yx_uint16 coordinate one step from coordinate yx in direction dir.
+ *
+ * If an invalid dir "d" is passed, "yx" remains unchanged.
+ */
+extern struct yx_uint16 mv_yx_in_dir(enum dir d, struct yx_uint16 yx);
+
 
-extern char yx_uint16_cmp (struct yx_uint16, struct yx_uint16);
-extern struct yx_uint16 mv_yx_in_dir (char, struct yx_uint16);
 
 #endif