--- ray/src/common/color.c	1993/03/02 09:09:51	2.6
+++ ray/src/common/color.c	1994/03/26 13:44:38	2.8
@@ -12,17 +12,15 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include  <stdio.h>
 
+#include  <math.h>
+
 #include  "color.h"
 
 #define  MINELEN	8	/* minimum scanline length for encoding */
 #define  MAXELEN	0x7fff	/* maximum scanline length for encoding */
 #define  MINRUN		4	/* minimum run length */
 
-#ifndef frexp
-extern double  frexp();
-#endif
 
-
 char *
 tempbuffer(len)			/* get a temporary buffer */
 unsigned  len;
@@ -243,7 +241,7 @@ double  r, g, b;
 		return;
 	}
 
-	d = frexp(d, &e) * 256.0 / d;
+	d = frexp(d, &e) * 255.9999 / d;
 
 	clr[RED] = r * d;
 	clr[GRN] = g * d;