--- ray/src/rt/o_instance.c	1990/12/15 16:43:58	1.9
+++ ray/src/rt/o_instance.c	2003/02/25 02:47:23	2.5
@@ -1,15 +1,12 @@
-/* Copyright (c) 1990 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: o_instance.c,v 2.5 2003/02/25 02:47:23 greg Exp $";
 #endif
-
 /*
  *  o_instance.c - routines for computing ray intersections with octrees.
- *
- *     11/11/88
  */
 
+#include "copyright.h"
+
 #include  "ray.h"
 
 #include  "instance.h"
@@ -19,27 +16,24 @@ o_instance(o, r)		/* compute ray intersection with oct
 OBJREC  *o;
 register RAY  *r;
 {
-	extern long  nrays;
 	RAY  rcont;
 	register INSTANCE  *in;
 	register int  i;
 					/* get the octree */
 	in = getinstance(o, IO_ALL);
-					/* copy old ray */
+					/* copy and transform ray */
 	copystruct(&rcont, r);
-					/* transform it */
-	rcont.rno = nrays;
-	rcont.ro = NULL;
-	rcont.rot = FHUGE;
 	multp3(rcont.rorg, r->rorg, in->x.b.xfm);
 	multv3(rcont.rdir, r->rdir, in->x.b.xfm);
 	for (i = 0; i < 3; i++)
 		rcont.rdir[i] /= in->x.b.sca;
-					/* trace it */
+	rcont.rmax *= in->x.b.sca;
+					/* clear and trace it */
+	rayclear(&rcont);
 	if (!localhit(&rcont, &in->obj->scube))
-		return(0);		/* missed */
+		return(0);			/* missed */
 	if (rcont.rot * in->x.f.sca >= r->rot)
-		return(0);		/* not close enough */
+		return(0);			/* not close enough */
 
 	if (o->omod != OVOID) {		/* if we have modifier, use it */
 		r->ro = o;