--- ray/src/common/random.h	2006/04/05 15:21:53	2.17
+++ ray/src/common/random.h	2015/07/16 05:08:57	2.22
@@ -1,9 +1,12 @@
-/* RCSid $Id: random.h,v 2.17 2006/04/05 15:21:53 greg Exp $ */
+/* RCSid $Id: random.h,v 2.22 2015/07/16 05:08:57 greg Exp $ */
 /*
  *  random.h - header file for random(3) and urand() function.
  */
 #ifndef _RAD_RANDOM_H_
 #define _RAD_RANDOM_H_
+
+#include <stdlib.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -17,31 +20,20 @@ extern "C" {
 #endif
 #define srandom(s)	srand((unsigned)(s))
 
-#define frandom()	(rand()*(1./RAND_MAX))
+#define frandom()	(rand()*(1./(RAND_MAX+.5)))
 
 #else
-#ifdef	BSD
 
-extern long  random();
-
-#define	 frandom()	(random()*(1./2147483648.))
-
-#else
-
-extern long  lrand48();
-extern double  drand48();
-
 #define	 random()	lrand48()
 #define  srandom(s)	srand48((long)(s))
 #define	 frandom()	drand48()
 
 #endif
-#endif
 
 extern unsigned short	*urperm;
 extern int	urmask;
 
-#define	 urand(i)	(urmask ? (urperm[(i)&urmask]+frandom())/(urmask+1) \
+#define	 urand(i)	(urmask ? (urperm[(i)&urmask]+frandom())/(urmask+1.) \
 				: frandom())
 
 extern int	initurand(int size);