+/* Update game log by appending "text", or by appending a "." if "text" is the
+ * same as the last one passed.
+ */
+extern void update_log(char * text);
+
+/* Return the offset necessary to center a map of "mapsize" on position "pos" in
+ * a frame of "framesize.
+ */
+extern uint16_t center_offset(uint16_t pos,
+ uint16_t mapsize, uint16_t framesize);