--- ray/src/rt/ambient.h	1991/08/20 10:02:43	1.2
+++ ray/src/rt/ambient.h	1995/04/27 14:12:09	2.5
@@ -12,6 +12,7 @@
  * and don't pass these vectors to fvect routines.
  */
 typedef struct ambrec {
+	unsigned long  latick;	/* last accessed tick */
 	float  pos[3];		/* position in space */
 	float  dir[3];		/* normal direction */
 	int  lvl;		/* recursion level of parent ray */
@@ -37,3 +38,7 @@ extern double  minarad;		/* minimum ambient radius */
 extern double  sumambient(), doambient(), makeambient();
 
 #define  AVGREFL	0.5	/* assumed average reflectance */
+
+#define  AMBVALSIZ	75	/* number of bytes in portable AMBVAL struct */
+#define  AMBMAGIC	557	/* magic number for ambient value files */
+#define  AMBFMT		"Radiance_ambval"	/* format id string */