--- ray/src/rt/o_instance.c	2003/07/21 22:30:19	2.7
+++ ray/src/rt/o_instance.c	2014/07/08 18:25:00	2.9
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: o_instance.c,v 2.7 2003/07/21 22:30:19 schorsch Exp $";
+static const char RCSid[] = "$Id: o_instance.c,v 2.9 2014/07/08 18:25:00 greg Exp $";
 #endif
 /*
  *  o_instance.c - routines for computing ray intersections with octrees.
@@ -8,18 +8,20 @@ static const char RCSid[] = "$Id: o_instance.c,v 2.7 2
 #include "copyright.h"
 
 #include  "ray.h"
-
 #include  "instance.h"
+#include  "rtotypes.h"
 
 
-o_instance(o, r)		/* compute ray intersection with octree */
-OBJREC  *o;
-register RAY  *r;
+int
+o_instance(		/* compute ray intersection with octree */
+	OBJREC  *o,
+	RAY  *r
+)
 {
 	RAY  rcont;
 	double  d;
-	register INSTANCE  *ins;
-	register int  i;
+	INSTANCE  *ins;
+	int  i;
 					/* get the octree */
 	ins = getinstance(o, IO_ALL);
 					/* copy and transform ray */