--- ray/src/rt/srcsamp.c	1991/10/22 15:45:21	1.4
+++ ray/src/rt/srcsamp.c	2003/02/25 02:47:23	2.8
@@ -1,13 +1,14 @@
-/* Copyright (c) 1991 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: srcsamp.c,v 2.8 2003/02/25 02:47:23 greg Exp $";
 #endif
-
 /*
  * Source sampling routines
+ *
+ *  External symbols declared in source.h
  */
 
+#include "copyright.h"
+
 #include  "ray.h"
 
 #include  "source.h"
@@ -15,6 +16,9 @@ static char SCCSid[] = "$SunId$ LBL";
 #include  "random.h"
 
 
+static int  cyl_partit(), flt_partit();
+
+
 double
 nextssamp(r, si)		/* compute sample for source, rtn. distance */
 register RAY  *r;		/* origin is read, direction is set */
@@ -24,11 +28,13 @@ register SRCINDEX  *si;		/* source index (modified to 
 	FVECT  vpos;
 	double  d;
 	register int  i;
-tryagain:
+nextsample:
 	while (++si->sp >= si->np) {	/* get next sample */
 		if (++si->sn >= nsources)
 			return(0.0);	/* no more */
-		if (srcsizerat <= FTINY)
+		if (source[si->sn].sflags & SSKIP)
+			si->np = 0;
+		else if (srcsizerat <= FTINY)
 			nopart(si, r);
 		else {
 			for (i = si->sn; source[i].sflags & SVIRTUAL;
@@ -74,31 +80,31 @@ tryagain:
 			r->rdir[i] -= r->rorg[i];
 					/* compute distance */
 	if ((d = normalize(r->rdir)) == 0.0)
-		goto tryagain;	/* at source! */
+		goto nextsample;		/* at source! */
 
 					/* compute sample size */
-	si->dom  = source[si->sn].ss2;
 	if (source[si->sn].sflags & SFLAT) {
-		si->dom *= sflatform(si->sn, r->rdir);
-		if (si->dom <= FTINY) {		/* behind source */
-			si->np = 0;
-			goto tryagain;
-		}
-		si->dom *= (double)(size[SU]*size[SV])/(MAXSPART*MAXSPART);
+		si->dom = sflatform(si->sn, r->rdir);
+		si->dom *= size[SU]*size[SV]/(MAXSPART*(double)MAXSPART);
 	} else if (source[si->sn].sflags & SCYL) {
-		si->dom *= scylform(si->sn, r->rdir);
-		si->dom *= (double)size[SU]/MAXSPART;
+		si->dom = scylform(si->sn, r->rdir);
+		si->dom *= size[SU]/(double)MAXSPART;
 	} else {
-		si->dom *= (double)(size[SU]*size[SV]*size[SW]) /
-				(MAXSPART*MAXSPART*MAXSPART) ;
+		si->dom = size[SU]*size[SV]*(double)size[SW] /
+				(MAXSPART*MAXSPART*(double)MAXSPART) ;
 	}
-	if (source[si->sn].sflags & SDISTANT)
+	if (source[si->sn].sflags & SDISTANT) {
+		si->dom *= source[si->sn].ss2;
 		return(FHUGE);
-	si->dom /= d*d;
+	}
+	if (si->dom <= 1e-4)
+		goto nextsample;		/* behind source? */
+	si->dom *= source[si->sn].ss2/(d*d);
 	return(d);		/* sample OK, return distance */
 }
 
 
+int
 skipparts(ct, sz, pp, pt)		/* skip to requested partition */
 int  ct[3], sz[3];		/* center and size of partition (returned) */
 register int  pp[2];		/* current index, number to skip (modified) */
@@ -130,6 +136,7 @@ unsigned char  *pt;		/* partition array */
 }
 
 
+void
 nopart(si, r)			/* single source partition */
 register SRCINDEX  *si;
 RAY  *r;
@@ -140,6 +147,7 @@ RAY  *r;
 }
 
 
+void
 cylpart(si, r)			/* partition a cylinder */
 SRCINDEX  *si;
 register RAY  *r;
@@ -165,8 +173,8 @@ register RAY  *r;
 		return;
 	}
 	safedist2 *= 4.*r->rweight*r->rweight/(srcsizerat*srcsizerat);
-	if (dist2 <= 4.*rad2 ||		/* point too close to subdivide? */
-			dist2cent >= safedist2) {	/* too far? */
+	if (dist2 <= 4.*rad2 ||		/* point too close to subdivide */
+			dist2cent >= safedist2) {	/* or too far */
 		setpart(si->spt, 0, S0);
 		si->np = 1;
 		return;
@@ -216,21 +224,32 @@ double  d2;
 }
 
 
+void
 flatpart(si, r)				/* partition a flat source */
 register SRCINDEX  *si;
-RAY  *r;
+register RAY  *r;
 {
-	register double  *vp;
+	register FLOAT  *vp;
+	FVECT  v;
 	double  du2, dv2;
 	int  pi;
 
+	clrpart(si->spt);
+	vp = source[si->sn].sloc;
+	v[0] = r->rorg[0] - vp[0];
+	v[1] = r->rorg[1] - vp[1];
+	v[2] = r->rorg[2] - vp[2];
+	vp = source[si->sn].snorm;
+	if (DOT(v,vp) <= FTINY) {	/* behind source */
+		si->np = 0;
+		return;
+	}
 	dv2 = 2.*r->rweight/srcsizerat;
 	dv2 *= dv2;
 	vp = source[si->sn].ss[SU];
 	du2 = dv2 * DOT(vp,vp);
 	vp = source[si->sn].ss[SV];
 	dv2 *= DOT(vp,vp);
-	clrpart(si->spt);
 	pi = 0;
 	si->np = flt_partit(r->rorg, si->spt, &pi, MAXSPART,
 		source[si->sn].sloc,
@@ -294,7 +313,7 @@ scylform(sn, dir)		/* compute cosine for cylinder's pr
 int  sn;
 register FVECT  dir;		/* assume normalized */
 {
-	register double  *dv;
+	register FLOAT  *dv;
 	double  d;
 
 	dv = source[sn].ss[SU];