--- ray/src/util/rad.c	1994/01/01 12:12:32	2.38
+++ ray/src/util/rad.c	1994/04/21 12:22:44	2.40
@@ -701,6 +701,8 @@ oconv()				/* run oconv and mkillum if necessary */
 			exit(1);
 		}
 		octreedate = time((time_t *)NULL);
+		if (octreedate < scenedate)	/* in case clock is off */
+			octreedate = scenedate;
 	}
 	if (oct1name == vval(OCTREE))		/* no mkillum? */
 		oct1date = octreedate > matdate ? octreedate : matdate;
@@ -727,6 +729,10 @@ oconv()				/* run oconv and mkillum if necessary */
 			exit(1);
 		}
 		oct0date = time((time_t *)NULL);
+		if (oct0date < octreedate)	/* in case clock is off */
+			oct0date = octreedate;
+		if (oct0date < illumdate)	/* ditto */
+			oct0date = illumdate;
 	}
 	mkillumopts(mkopts);			/* build mkillum command */
 	mktemp(illumtmp);
@@ -755,6 +761,8 @@ oconv()				/* run oconv and mkillum if necessary */
 		exit(1);
 	}
 	oct1date = time((time_t *)NULL);
+	if (oct1date < oct0date)	/* in case clock is off */
+		oct1date = oct0date;
 	rmfile(illumtmp);
 }
 
@@ -850,6 +858,8 @@ char	*po;
 			&siz[0], &org[1], &siz[1], &org[2], &siz[2]) != 6)
 		badvalue(ZONE);
 	siz[0] -= org[0]; siz[1] -= org[1]; siz[2] -= org[2];
+	if (siz[0] <= FTINY | siz[1] <= FTINY | siz[2] <= FTINY)
+		badvalue(ZONE);
 	getoctcube(org, &d);
 	d *= 3./(siz[0]+siz[1]+siz[2]);
 	switch (vscale(DETAIL)) {
@@ -916,6 +926,8 @@ char	*po;
 			&siz[0], &org[1], &siz[1], &org[2], &siz[2]) != 6)
 		badvalue(ZONE);
 	siz[0] -= org[0]; siz[1] -= org[1]; siz[2] -= org[2];
+	if (siz[0] <= FTINY | siz[1] <= FTINY | siz[2] <= FTINY)
+		badvalue(ZONE);
 	getoctcube(org, &d);
 	d *= 3./(siz[0]+siz[1]+siz[2]);
 	switch (vscale(DETAIL)) {
@@ -985,6 +997,8 @@ char	*po;
 			&siz[0], &org[1], &siz[1], &org[2], &siz[2]) != 6)
 		badvalue(ZONE);
 	siz[0] -= org[0]; siz[1] -= org[1]; siz[2] -= org[2];
+	if (siz[0] <= FTINY | siz[1] <= FTINY | siz[2] <= FTINY)
+		badvalue(ZONE);
 	getoctcube(org, &d);
 	d *= 3./(siz[0]+siz[1]+siz[2]);
 	switch (vscale(DETAIL)) {
@@ -1157,6 +1171,8 @@ register char	*vs;
 			badvalue(ZONE);
 		for (i = 0; i < 3; i++) {
 			dim[i] -= cent[i];
+			if (dim[i] <= FTINY)
+				badvalue(ZONE);
 			cent[i] += .5*dim[i];
 		}
 		mult = vlet(ZONE)=='E' ? 2. : .45 ;