diff --git a/include/vision.h b/include/vision.h
new file mode 100644
index 000000000..87925d9ae
--- /dev/null
+++ b/include/vision.h
@@ -0,0 +1,58 @@
+/*	SCCS Id: @(#)vision.h	3.3	95/01/26	*/
+/* Copyright (c) Dean Luick, with acknowledgements to Dave Cohrs, 1990. */
+/* NetHack may be freely redistributed.  See license for details.	*/
+
+#ifndef VISION_H
+#define VISION_H
+
+#if 0	/* (moved to decl.h) */
+extern boolean vision_full_recalc;	/* TRUE if need vision recalc */
+extern char **viz_array;		/* could see/in sight row pointers */
+extern char *viz_rmin;			/* min could see indices */
+extern char *viz_rmax;			/* max could see indices */
+#endif
+#define COULD_SEE 0x1		/* location could be seen, if it were lit */
+#define IN_SIGHT  0x2		/* location can be seen */
+#define TEMP_LIT  0x4		/* location is temporarily lit */
+
+/*
+ * Light source sources
+ */
+#define LS_OBJECT 0
+#define LS_MONSTER 1
+
+/*
+ *  cansee()	- Returns true if the hero can see the location.
+ *
+ *  couldsee()	- Returns true if the hero has a clear line of sight to
+ *		  the location.
+ */
+#define cansee(x,y)	(viz_array[y][x] & IN_SIGHT)
+#define couldsee(x,y)	(viz_array[y][x] & COULD_SEE)
+#define templit(x,y)	(viz_array[y][x] & TEMP_LIT)
+
+/*
+ *  The following assume the monster is not blind.
+ *
+ *  m_cansee()	- Returns true if the monster can see the given location.
+ *
+ *  m_canseeu() - Returns true if the monster could see the hero.  Assumes
+ *		  that if the hero has a clear line of sight to the monster's
+ *		  location and the hero is visible, then monster can see the
+ *		  hero.
+ */
+#define m_cansee(mtmp,x2,y2)	clear_path((mtmp)->mx,(mtmp)->my,(x2),(y2))
+
+#define m_canseeu(m)	((!Invis || perceives((m)->data)) && \
+			  !(Underwater || u.uburied || (m)->mburied) ? \
+			     couldsee((m)->mx,(m)->my) : 0)
+
+/*
+ *  Circle information
+ */
+#define MAX_RADIUS 15	/* this is in points from the source */
+
+/* Use this macro to get a list of distances of the edges (see vision.c). */
+#define circle_ptr(z) (&circle_data[(int)circle_start[z]])
+
+#endif /* VISION_H */