--- ray/src/rt/source.c	1991/06/25 12:32:51	1.37
+++ ray/src/rt/source.c	1991/08/13 12:16:37	1.43
@@ -1,4 +1,4 @@
-/* Copyright (c) 1990 Regents of the University of California */
+/* Copyright (c) 1991 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ LBL";
@@ -86,6 +86,12 @@ marksources()			/* find and mark source objects */
 			source[ns].sflags |= SSPOT;
 			if ((source[ns].sl.s = makespot(m)) == NULL)
 				goto memerr;
+			if (source[ns].sflags & SFLAT &&
+				!checkspot(source[ns].sl.s,source[ns].snorm)) {
+				objerror(o, WARNING,
+					"invalid spotlight direction");
+				source[ns].sflags |= SSKIP;
+			}
 		}
 	}
 	if (nsources <= 0) {
@@ -122,14 +128,6 @@ register int  sn;		/* source number */
 	sr->rsrc = sn;				/* remember source */
 						/* get source direction */
 	if (source[sn].sflags & SDISTANT) {
-		if (source[sn].sflags & SSPOT) {	/* check location */
-			for (i = 0; i < 3; i++)
-				vd[i] = sr->rorg[i] - source[sn].sl.s->aim[i];
-			d = DOT(source[sn].sloc,vd);
-			d = DOT(vd,vd) - d*d;
-			if (PI*d > source[sn].sl.s->siz)
-				return(0.0);
-		}
 						/* constant direction */
 		VCOPY(sr->rdir, source[sn].sloc);
 	} else {				/* compute direction */
@@ -142,13 +140,10 @@ register int  sn;		/* source number */
 	}
 	if (dstrsrc > FTINY) {
 					/* distribute source direction */
-		dimlist[ndims++] = sn;
-		for (i = 0; i < 3; i++) {
-			dimlist[ndims] = i + 8831;
-			vd[i] = dstrsrc * source[sn].ss *
-		(1.0 - 2.0*urand(ilhash(dimlist,ndims+1)+samplendx));
-		}
-		ndims--;
+		dimlist[ndims] = sn + 8831;
+		peano(vd, 3, urand(ilhash(dimlist,ndims+1)+samplendx), .01);
+		for (i = 0; i < 3; i++)
+			vd[i] = dstrsrc * source[sn].ss * (1. - 2.*vd[i]);
 		if (source[sn].sflags & SFLAT) {	/* project offset */
 			d = DOT(vd, source[sn].snorm);
 			for (i = 0; i < 3; i++)
@@ -156,19 +151,29 @@ register int  sn;		/* source number */
 		}
 		for (i = 0; i < 3; i++)		/* offset source direction */
 			sr->rdir[i] += vd[i];
+						/* normalize */
+		d = normalize(sr->rdir);
 
-	} else if (source[sn].sflags & SDISTANT)
-						/* already normalized */
-		return(source[sn].ss2);
+	} else if (!(source[sn].sflags & SDISTANT))
+						/* normalize direction */
+		d = normalize(sr->rdir);
 
-	if ((d = normalize(sr->rdir)) == 0.0)
-						/* at source! */
+	if (source[sn].sflags & SDISTANT) {
+		if (source[sn].sflags & SSPOT) {	/* check location */
+			for (i = 0; i < 3; i++)
+				vd[i] = source[sn].sl.s->aim[i] - sr->rorg[i];
+			d = DOT(sr->rdir,vd);
+			if (d <= FTINY)
+				return(0.0);
+			d = DOT(vd,vd) - d*d;
+			if (PI*d > source[sn].sl.s->siz)
+				return(0.0);
+		}
+		return(source[sn].ss2);		/* domega constant */
+	}
+						/* check direction */
+	if (d == 0.0)
 		return(0.0);
-	
-	if (source[sn].sflags & SDISTANT)
-						/* domega constant */
-		return(source[sn].ss2);
-
 						/* check proximity */
 	if (source[sn].sflags & SPROX &&
 			d > source[sn].sl.prox)
@@ -239,6 +244,7 @@ RAY  *r;			/* ray that hit surface */
 int  (*f)();			/* direct component coefficient function */
 char  *p;			/* data for f */
 {
+	extern int  (*trace)();
 	extern double  pow();
 	register int  sn;
 	int  nshadcheck, ncnts;
@@ -308,6 +314,8 @@ char  *p;			/* data for f */
 				source[cntord[sn].sno].sflags & SFOLLOW )) {
 						/* follow entire path */
 			raycont(&sr);
+			if (trace != NULL)
+				(*trace)(&sr);	/* trace execution */
 			if (bright(sr.rcol) <= FTINY)
 				continue;	/* missed! */
 			copycolor(srccnt[cntord[sn].sno].val, sr.rcol);