X-Git-Url: https://plomlompom.com/repos/?a=blobdiff_plain;f=src%2Fyx_uint16.h;h=29298e5ded0f4b97f79f12d2d5e3d04b5b934a37;hb=120715d0a4a308cdf748e1925be472ed6a59f092;hp=c1479c0054c1c035b03b437c190fed0253514f77;hpb=64e1bc2a874308530b7b45c33ed5d37f34f5f8be;p=plomrogue

diff --git a/src/yx_uint16.h b/src/yx_uint16.h
index c1479c0..29298e5 100644
--- a/src/yx_uint16.h
+++ b/src/yx_uint16.h
@@ -1,6 +1,38 @@
-struct yx_uint16 {
-  uint16_t y;
-  uint16_t x; };
+/* yx_uint16.h
+ *
+ * Structs and routines for coordinates and movement in 2-dimensional space
+ * (such as the ncurses screen and game maps).
+ */
 
-extern char yx_uint16_cmp (struct yx_uint16, struct yx_uint16);
+#ifndef YX_UINT16_H
+#define YX_UINT16_H
 
+
+
+#include <stdint.h> /* for 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 a and b are equal, else 0. */
+extern char yx_uint16_cmp(struct yx_uint16 a, struct yx_uint16 b);
+
+/* Return yx_uint16 coordinate one step from coordinate yx in direction dir. */
+extern struct yx_uint16 mv_yx_in_dir(enum dir d, struct yx_uint16 yx);
+
+#endif