--- ray/src/common/urand.c	1991/05/17 12:55:27	1.1
+++ ray/src/common/urand.c	1992/09/05 13:40:55	2.2
@@ -1,11 +1,11 @@
-/* Copyright (c) 1991 Regents of the University of California */
+/* Copyright (c) 1992 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
 #endif
 
 /*
- * Uncorrelated (anticorrelated) random function
+ * Anticorrelated random function due to Christophe Schlick
  */
 
 #include  "random.h"
@@ -14,7 +14,7 @@ static char SCCSid[] = "$SunId$ LBL";
 
 extern char  *malloc();
 
-short  *urperm;		/* urand() permutation */
+short  *urperm = NULL;	/* urand() permutation */
 int  urmask;		/* bits used in permutation */
 
 
@@ -24,6 +24,8 @@ int  size;
 	int  order, n;
 	register int  i, offset;
 
+	if (urperm != NULL)
+		free((char *)urperm);
 	size--;
 	for (i = 1; size >>= 1; i++)
 		;
@@ -44,4 +46,19 @@ int  size;
 			else
 				urperm[i+offset]++;
 		}
+}
+
+
+int
+ilhash(d, n)			/* hash a set of integer values */
+register int  *d;
+register int  n;
+{
+	static int  tab[8] = {13623,353,1637,5831,2314,3887,5832,8737};
+	register int  hval;
+
+	hval = 0;
+	while (n-- > 0)
+		hval += *d++ * tab[n&7];
+	return(hval);
 }