--- ray/src/rt/rtrace.c	2021/01/27 00:00:05	2.100
+++ ray/src/rt/rtrace.c	2021/02/16 22:06:00	2.101
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: rtrace.c,v 2.100 2021/01/27 00:00:05 greg Exp $";
+static const char	RCSid[] = "$Id: rtrace.c,v 2.101 2021/02/16 22:06:00 greg Exp $";
 #endif
 /*
  *  rtrace.c - program and variables for individual ray tracing.
@@ -420,21 +420,22 @@ rtcompute(			/* compute and print ray value(s) */
 )
 {
 					/* set up ray */
-	rayorigin(&thisray, PRIMARY, NULL, NULL);
 	if (imm_irrad) {
 		VSUM(thisray.rorg, org, dir, 1.1e-4);
 		thisray.rdir[0] = -dir[0];
 		thisray.rdir[1] = -dir[1];
 		thisray.rdir[2] = -dir[2];
 		thisray.rmax = 0.0;
-		thisray.revf = rayirrad;
 	} else {
 		VCOPY(thisray.rorg, org);
 		VCOPY(thisray.rdir, dir);
 		thisray.rmax = dmax;
-		if (castonly)
-			thisray.revf = raycast;
 	}
+	rayorigin(&thisray, PRIMARY, NULL, NULL);
+	if (imm_irrad)
+		thisray.revf = rayirrad;
+	else if (castonly)
+		thisray.revf = raycast;
 	if (ray_pnprocs > 1) {		/* multiprocessing FIFO? */
 		if (ray_fifo_in(&thisray) < 0)
 			error(USER, "lost children");