--- ray/src/rt/rtrace.c	1997/01/14 19:54:27	2.23
+++ ray/src/rt/rtrace.c	1997/10/17 10:14:37	2.25
@@ -1,7 +1,7 @@
-/* Copyright (c) 1995 Regents of the University of California */
+/* Copyright (c) 1997 Silicon Graphics, Inc. */
 
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static char SCCSid[] = "$SunId$ SGI";
 #endif
 
 /*
@@ -37,6 +37,7 @@ int  ndims = 0;				/* number of sampling dimensions */
 int  samplendx = 0;			/* index for this sample */
 
 int  imm_irrad = 0;			/* compute immediate irradiance? */
+int  lim_dist = 0;			/* limit distance? */
 
 int  inform = 'a';			/* input format */
 int  outform = 'a';			/* output format */
@@ -82,7 +83,9 @@ char  *amblist[128];			/* ambient include/exclude list
 int  ambincl = -1;			/* include == 1, exclude == 0 */
 
 extern OBJREC  Lamb;			/* a Lambertian surface */
+extern OBJREC  Aftplane;		/* aft clipping object */
 
+
 static RAY  thisray;			/* for our convenience */
 
 static int  oputo(), oputd(), oputv(), oputl(), oputL(),
@@ -128,6 +131,7 @@ char  *fname;
 	long  vcount = hresolu>1 ? hresolu*vresolu : vresolu;
 	long  nextflush = hresolu;
 	FILE  *fp;
+	double	d;
 	FVECT  orig, direc;
 					/* set up input */
 	if (fname == NULL)
@@ -162,20 +166,25 @@ char  *fname;
 	while (getvec(orig, inform, fp) == 0 &&
 			getvec(direc, inform, fp) == 0) {
 
-		if (normalize(direc) == 0.0) {		/* zero ==> flush */
-			fflush(stdout);
-			continue;
-		}
-		samplendx++;
+		d = normalize(direc);
+		if (d == 0.0) {				/* zero ==> flush */
+			bogusray();
+			if (--nextflush <= 0) {
+				fflush(stdout);
+				nextflush = hresolu;
+			}
+		} else {
+			samplendx++;
 							/* compute and print */
-		if (imm_irrad)
-			irrad(orig, direc);
-		else
-			rad(orig, direc);
+			if (imm_irrad)
+				irrad(orig, direc);
+			else
+				rad(orig, direc, lim_dist ? d : 0.0);
 							/* flush if time */
-		if (--nextflush == 0) {
-			fflush(stdout);
-			nextflush = hresolu;
+			if (--nextflush == 0) {
+				fflush(stdout);
+				nextflush = hresolu;
+			}
 		}
 		if (ferror(stdout))
 			error(SYSTEM, "write error");
@@ -246,16 +255,31 @@ register char  *vs;
 }
 
 
-rad(org, dir)			/* compute and print ray value(s) */
+bogusray()			/* print out empty record */
+{
+	thisray.rorg[0] = thisray.rorg[1] = thisray.rorg[2] =
+	thisray.rdir[0] = thisray.rdir[1] = thisray.rdir[2] = 0.0;
+	rayorigin(&thisray, NULL, PRIMARY, 1.0);
+	printvals(&thisray);
+}
+
+
+rad(org, dir, dmax)		/* compute and print ray value(s) */
 FVECT  org, dir;
+double	dmax;
 {
 	VCOPY(thisray.rorg, org);
 	VCOPY(thisray.rdir, dir);
-	thisray.rmax = 0.0;
+	thisray.rmax = dmax;
 	rayorigin(&thisray, NULL, PRIMARY, 1.0);
-	if (castonly)
-		localhit(&thisray, &thescene) || sourcehit(&thisray);
-	else
+	if (castonly) {
+		if (!localhit(&thisray, &thescene))
+			if (thisray.ro == &Aftplane) {	/* clipped */
+				thisray.ro = NULL;
+				thisray.rot = FHUGE;
+			} else
+				sourcehit(&thisray);
+	} else
 		rayvalue(&thisray);
 	printvals(&thisray);
 }