--- ray/src/common/clip.c	1989/02/02 10:33:01	1.1
+++ ray/src/common/clip.c	1993/12/19 22:49:28	2.2
@@ -1,4 +1,4 @@
-/* Copyright (c) 1986 Regents of the University of California */
+/* Copyright (c) 1993 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
@@ -10,16 +10,21 @@ static char SCCSid[] = "$SunId$ LBL";
  *     8/28/85
  */
 
+#include  "fvect.h"
+
 #include  "plocate.h"
 
+#define MAXITER		6	/* maximum possible number of iterations */
 
+
 clip(ep1, ep2, min, max)	/* clip a line segment to a box */
-double  *ep1, *ep2;
-double  min[3], max[3];
+FLOAT  *ep1, *ep2;
+FVECT  min, max;
 {
+	int  itlim = MAXITER;
 	int  loc1, loc2;
 	int  accept;
-	double  *dp;
+	FLOAT  *dp;
 	double  d;
 	register int  i, j;
 
@@ -39,6 +44,9 @@ double  min[3], max[3];
 	
 	while (!((accept = !(loc1 | loc2)) || (loc1 & loc2))) {
 	
+		if (itlim-- <= 0)	/* past theoretical limit? */
+			return(0);	/* quit fooling around */
+
 		if (!loc1) {		/* make sure first point is outside */
 			dp = ep1; ep1 = ep2; ep2 = dp;
 			i = loc1; loc1 = loc2; loc2 = i;