--- ray/src/rt/m_bsdf.c	2012/03/30 15:08:40	2.18
+++ ray/src/rt/m_bsdf.c	2013/07/04 15:14:45	2.24
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: m_bsdf.c,v 2.18 2012/03/30 15:08:40 greg Exp $";
+static const char RCSid[] = "$Id: m_bsdf.c,v 2.24 2013/07/04 15:14:45 greg Exp $";
 #endif
 /*
  *  Shading for materials with BSDFs taken from XML data files
@@ -122,7 +122,9 @@ direct_bsdf_OK(COLOR cval, FVECT ldir, double omega, B
 			return(0);
 	}
 	sf = specjitter * ndp->pr->rweight;
-	if (25.*tomega <= omega)
+	if (tomega <= .0)
+		nsamp = 1;
+	else if (25.*tomega <= omega)
 		nsamp = 100.*sf + .5;
 	else
 		nsamp = 4.*sf*omega/tomega + .5;
@@ -380,7 +382,10 @@ sample_sdf(BSDFDAT *ndp, int sflags)
 
 	if (sflags == SDsampSpT) {
 		unsc = ndp->tunsamp;
-		dfp = ndp->sd->tf;
+		if (ndp->pr->rod > 0)
+			dfp = (ndp->sd->tf != NULL) ? ndp->sd->tf : ndp->sd->tb;
+		else
+			dfp = (ndp->sd->tb != NULL) ? ndp->sd->tb : ndp->sd->tf;
 		cvt_sdcolor(unsc, &ndp->sd->tLamb);
 	} else /* sflags == SDsampSpR */ {
 		unsc = ndp->runsamp;
@@ -470,7 +475,7 @@ m_bsdf(OBJREC *m, RAY *r)
 	} else {
 		if (m->oargs.nfargs < 6) {	/* check invisible backside */
 			if (!backvis && (nd.sd->rb == NULL) &
-						(nd.sd->tf == NULL)) {
+					(nd.sd->tb == NULL)) {
 				SDfreeCache(nd.sd);
 				raytrans(r);
 				return(1);
@@ -500,10 +505,14 @@ m_bsdf(OBJREC *m, RAY *r)
 	upvec[1] = evalue(mf->ep[2]);
 	upvec[2] = evalue(mf->ep[3]);
 						/* return to world coords */
-	if (mf->f != &unitxf) {
-		multv3(upvec, upvec, mf->f->xfm);
-		nd.thick *= mf->f->sca;
+	if (mf->fxp != &unitxf) {
+		multv3(upvec, upvec, mf->fxp->xfm);
+		nd.thick *= mf->fxp->sca;
 	}
+	if (r->rox != NULL) {
+		multv3(upvec, upvec, r->rox->f.xfm);
+		nd.thick *= r->rox->f.sca;
+	}
 	raynormal(nd.pnorm, r);
 						/* compute local BSDF xform */
 	ec = SDcompXform(nd.toloc, nd.pnorm, upvec);
@@ -515,15 +524,15 @@ m_bsdf(OBJREC *m, RAY *r)
 	}
 	if (!ec)
 		ec = SDinvXform(nd.fromloc, nd.toloc);
-						/* determine BSDF resolution */
-	if (!ec)
-		ec = SDsizeBSDF(nd.sr_vpsa, nd.vray, NULL,
-						SDqueryMin+SDqueryMax, nd.sd);
 	if (ec) {
-		objerror(m, WARNING, transSDError(ec));
-		SDfreeCache(nd.sd);
+		objerror(m, WARNING, "Illegal orientation vector");
 		return(1);
 	}
+						/* determine BSDF resolution */
+	ec = SDsizeBSDF(nd.sr_vpsa, nd.vray, NULL, SDqueryMin+SDqueryMax, nd.sd);
+	if (ec)
+		objerror(m, USER, transSDError(ec));
+
 	nd.sr_vpsa[0] = sqrt(nd.sr_vpsa[0]);
 	nd.sr_vpsa[1] = sqrt(nd.sr_vpsa[1]);
 	if (!hitfront) {			/* perturb normal towards hit */
@@ -567,7 +576,8 @@ m_bsdf(OBJREC *m, RAY *r)
 			flipsurface(r);
 	}
 						/* add direct component */
-	if ((bright(nd.tdiff) <= FTINY) & (nd.sd->tf == NULL)) {
+	if ((bright(nd.tdiff) <= FTINY) & (nd.sd->tf == NULL) &
+					(nd.sd->tb == NULL)) {
 		direct(r, dir_brdf, &nd);	/* reflection only */
 	} else if (nd.thick == 0) {
 		direct(r, dir_bsdf, &nd);	/* thin surface scattering */