--- ray/src/cv/bsdfinterp.c	2012/10/23 05:10:42	2.3
+++ ray/src/cv/bsdfinterp.c	2014/10/26 17:35:53	2.20
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: bsdfinterp.c,v 2.3 2012/10/23 05:10:42 greg Exp $";
+static const char RCSid[] = "$Id: bsdfinterp.c,v 2.20 2014/10/26 17:35:53 greg Exp $";
 #endif
 /*
  * Interpolate BSDF data from radial basis functions in advection mesh.
@@ -51,7 +51,7 @@ order_triangle(MIGRATION *miga[3])
 		insert_vert(vert, miga[i]->rbfv[1]);
 	}
 						/* should be just 3 vertices */
-	if ((vert[3] == NULL) | (vert[4] != NULL))
+	if ((vert[2] == NULL) | (vert[3] != NULL))
 		return(0);
 						/* identify edge 0 */
 	for (i = 3; i--; )
@@ -85,17 +85,31 @@ order_triangle(MIGRATION *miga[3])
 	return(1);
 }
 
-/* Determine if we are close enough to the given edge */
+/* Determine if we are close enough to an edge */
 static int
 on_edge(const MIGRATION *ej, const FVECT ivec)
 {
-	double	cos_a = DOT(ej->rbfv[0]->invec, ivec);
-	double	cos_b = DOT(ej->rbfv[1]->invec, ivec);
-	double	cos_c = DOT(ej->rbfv[0]->invec, ej->rbfv[1]->invec);
-	double	cos_aplusb = cos_a*cos_b -
-				sqrt((1.-cos_a*cos_a)*(1.-cos_b*cos_b));
+	double	cos_a, cos_b, cos_c, cos_aplusb;
+					/* use triangle inequality */
+	cos_a = DOT(ej->rbfv[0]->invec, ivec);
+	if (cos_a <= 0)
+		return(0);
+	if (cos_a >= 1.)		/* handles rounding error */
+		return(1);
 
-	return(cos_aplusb - cos_c < .01);
+	cos_b = DOT(ej->rbfv[1]->invec, ivec);
+	if (cos_b <= 0)
+		return(0);
+	if (cos_b >= 1.)
+		return(1);
+
+	cos_aplusb = cos_a*cos_b - sqrt((1.-cos_a*cos_a)*(1.-cos_b*cos_b));
+	if (cos_aplusb <= 0)
+		return(0);
+
+	cos_c = DOT(ej->rbfv[0]->invec, ej->rbfv[1]->invec);
+
+	return(cos_c - cos_aplusb < .001);
 }
 
 /* Determine if we are inside the given triangle */
@@ -116,48 +130,74 @@ in_tri(const RBFNODE *v1, const RBFNODE *v2, const RBF
 	return(sgn2 == sgn3);
 }
 
-/* Compute intersection with the given position over remaining mesh */
+/* Test (and set) bitmap for edge */
 static int
-in_mesh(MIGRATION *miga[3], unsigned char *emap, int nedges,
-			const FVECT ivec, MIGRATION *mig)
+check_edge(unsigned char *emap, int nedges, const MIGRATION *mig, int mark)
 {
-	MIGRATION	*ej1, *ej2;
-	RBFNODE		*tv;
-	int		ejndx;
-						/* check visitation record */
+	int	ejndx, bit2check;
+
 	if (mig->rbfv[0]->ord > mig->rbfv[1]->ord)
 		ejndx = mig->rbfv[1]->ord + (nedges-1)*mig->rbfv[0]->ord;
 	else
 		ejndx = mig->rbfv[0]->ord + (nedges-1)*mig->rbfv[1]->ord;
-	if (emap[ejndx>>3] & 1<<(ejndx&07))	/* tested already? */
+
+	bit2check = 1<<(ejndx&07);
+
+	if (emap[ejndx>>3] & bit2check)
 		return(0);
-	emap[ejndx>>3] |= 1<<(ejndx&07);	/* else mark & test it */
+	if (mark)
+		emap[ejndx>>3] |= bit2check;
+	return(1);
+}
+
+/* Compute intersection with the given position over remaining mesh */
+static int
+in_mesh(MIGRATION *miga[3], unsigned char *emap, int nedges,
+			const FVECT ivec, MIGRATION *mig)
+{
+	RBFNODE		*tv[2];
+	MIGRATION	*sej[2], *dej[2];
+	int		i;
+						/* check visitation record */
+	if (!check_edge(emap, nedges, mig, 1))
+		return(0);
 	if (on_edge(mig, ivec)) {
 		miga[0] = mig;			/* close enough to edge */
 		return(1);
 	}
-						/* do triangles either side */
-	for (ej1 = mig->rbfv[0]->ejl; ej1 != NULL;
-				ej1 = nextedge(mig->rbfv[0],ej1)) {
-		if (ej1 == mig)
+	if (!get_triangles(tv, mig))		/* do triangles either side? */
+		return(0);
+	for (i = 2; i--; ) {			/* identify edges to check */
+		MIGRATION	*ej;
+		sej[i] = dej[i] = NULL;
+		if (tv[i] == NULL)
 			continue;
-		tv = opp_rbf(mig->rbfv[0],ej1);
-		for (ej2 = tv->ejl; ej2 != NULL; ej2 = nextedge(tv,ej2))
-			if (opp_rbf(tv,ej2) == mig->rbfv[1]) {
-				if (in_mesh(miga, emap, nedges, ivec, ej1))
-					return(1);
-				if (in_mesh(miga, emap, nedges, ivec, ej2))
-					return(1);
-				if (in_tri(mig->rbfv[0], mig->rbfv[1],
-						tv, ivec)) {
-					miga[0] = mig;
-					miga[1] = ej1;
-					miga[2] = ej2;
-					return(1);
-				}
+		for (ej = tv[i]->ejl; ej != NULL; ej = nextedge(tv[i],ej)) {
+			RBFNODE	*rbfop = opp_rbf(tv[i],ej);
+			if (rbfop == mig->rbfv[0]) {
+				if (check_edge(emap, nedges, ej, 0))
+					sej[i] = ej;
+			} else if (rbfop == mig->rbfv[1]) {
+				if (check_edge(emap, nedges, ej, 0))
+					dej[i] = ej;
 			}
+		}
 	}
-	return(0);
+	for (i = 2; i--; ) {			/* check triangles just once */
+		if (sej[i] != NULL && in_mesh(miga, emap, nedges, ivec, sej[i]))
+			return(1);
+		if (dej[i] != NULL && in_mesh(miga, emap, nedges, ivec, dej[i]))
+			return(1);
+		if ((sej[i] == NULL) | (dej[i] == NULL))
+			continue;
+		if (in_tri(mig->rbfv[0], mig->rbfv[1], tv[i], ivec)) {
+			miga[0] = mig;
+			miga[1] = sej[i];
+			miga[2] = dej[i];
+			return(1);
+		}
+	}
+	return(0);				/* not near this edge */
 }
 
 /* Find edge(s) for interpolating the given vector, applying symmetry */
@@ -166,21 +206,28 @@ get_interp(MIGRATION *miga[3], FVECT invec)
 {
 	miga[0] = miga[1] = miga[2] = NULL;
 	if (single_plane_incident) {		/* isotropic BSDF? */
-		RBFNODE	*rbf;			/* find edge we're on */
-		for (rbf = dsf_list; rbf != NULL; rbf = rbf->next) {
-			if (input_orient*rbf->invec[2] < input_orient*invec[2])
-				break;
-			if (rbf->next != NULL &&
-					input_orient*rbf->next->invec[2] <
-							input_orient*invec[2]) {
-				for (miga[0] = rbf->ejl; miga[0] != NULL;
-						miga[0] = nextedge(rbf,miga[0]))
-					if (opp_rbf(rbf,miga[0]) == rbf->next)
-						return(0);
-				break;
+	    RBFNODE	*rbf;			/* find edge we're on */
+	    for (rbf = dsf_list; rbf != NULL; rbf = rbf->next) {
+		if (input_orient*rbf->invec[2] < input_orient*invec[2]-FTINY)
+			break;
+		if (rbf->next != NULL && input_orient*rbf->next->invec[2] <
+						input_orient*invec[2]+FTINY) {
+		    for (miga[0] = rbf->ejl; miga[0] != NULL;
+					miga[0] = nextedge(rbf,miga[0]))
+			if (opp_rbf(rbf,miga[0]) == rbf->next) {
+				double	nf = 1. -
+					rbf->next->invec[2]*rbf->next->invec[2];
+				if (nf > FTINY) {	/* rotate to match */
+					nf = sqrt((1.-invec[2]*invec[2])/nf);
+					invec[0] = nf*rbf->next->invec[0];
+					invec[1] = nf*rbf->next->invec[1];
+				}
+				return(0);	/* rotational symmetry */
 			}
+		    break;
 		}
-		return(-1);			/* outside range! */
+	    }
+	    return(-1);				/* outside range! */
 	}
 	{					/* else use triangle mesh */
 		int		sym = use_symmetry(invec);
@@ -197,9 +244,14 @@ get_interp(MIGRATION *miga[3], FVECT invec)
 			exit(1);
 		}
 						/* identify intersection  */
-		if (!in_mesh(miga, emap, nedges, invec, mig_list))
+		if (!in_mesh(miga, emap, nedges, invec, mig_list)) {
+#ifdef DEBUG
+			fprintf(stderr,
+			"Incident angle (%.1f,%.1f) deg. outside mesh\n",
+					get_theta180(invec), get_phi360(invec));
+#endif
 			sym = -1;		/* outside mesh */
-		else if (miga[1] != NULL &&
+		} else if (miga[1] != NULL &&
 				(miga[2] == NULL || !order_triangle(miga))) {
 #ifdef DEBUG
 			fputs("Munged triangle in get_interp()\n", stderr);
@@ -211,85 +263,11 @@ get_interp(MIGRATION *miga[3], FVECT invec)
 	}
 }
 
-/* Advect and allocate new RBF along edge */
-static RBFNODE *
-e_advect_rbf(const MIGRATION *mig, const FVECT invec)
-{
-	RBFNODE		*rbf;
-	int		n, i, j;
-	double		t, full_dist;
-						/* get relative position */
-	t = acos(DOT(invec, mig->rbfv[0]->invec));
-	if (t < M_PI/GRIDRES) {			/* near first DSF */
-		n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[0]->nrbf-1);
-		rbf = (RBFNODE *)malloc(n);
-		if (rbf == NULL)
-			goto memerr;
-		memcpy(rbf, mig->rbfv[0], n);	/* just duplicate */
-		return(rbf);
-	}
-	full_dist = acos(DOT(mig->rbfv[0]->invec, mig->rbfv[1]->invec));
-	if (t > full_dist-M_PI/GRIDRES) {	/* near second DSF */
-		n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[1]->nrbf-1);
-		rbf = (RBFNODE *)malloc(n);
-		if (rbf == NULL)
-			goto memerr;
-		memcpy(rbf, mig->rbfv[1], n);	/* just duplicate */
-		return(rbf);
-	}
-	t /= full_dist;	
-	n = 0;					/* count migrating particles */
-	for (i = 0; i < mtx_nrows(mig); i++)
-	    for (j = 0; j < mtx_ncols(mig); j++)
-		n += (mtx_coef(mig,i,j) > FTINY);
-#ifdef DEBUG
-	fprintf(stderr, "Input RBFs have %d, %d nodes -> output has %d\n",
-			mig->rbfv[0]->nrbf, mig->rbfv[1]->nrbf, n);
-#endif
-	rbf = (RBFNODE *)malloc(sizeof(RBFNODE) + sizeof(RBFVAL)*(n-1));
-	if (rbf == NULL)
-		goto memerr;
-	rbf->next = NULL; rbf->ejl = NULL;
-	VCOPY(rbf->invec, invec);
-	rbf->nrbf = n;
-	rbf->vtotal = 1.-t + t*mig->rbfv[1]->vtotal/mig->rbfv[0]->vtotal;
-	n = 0;					/* advect RBF lobes */
-	for (i = 0; i < mtx_nrows(mig); i++) {
-	    const RBFVAL	*rbf0i = &mig->rbfv[0]->rbfa[i];
-	    const float		peak0 = rbf0i->peak;
-	    const double	rad0 = R2ANG(rbf0i->crad);
-	    FVECT		v0;
-	    float		mv;
-	    ovec_from_pos(v0, rbf0i->gx, rbf0i->gy);
-	    for (j = 0; j < mtx_ncols(mig); j++)
-		if ((mv = mtx_coef(mig,i,j)) > FTINY) {
-			const RBFVAL	*rbf1j = &mig->rbfv[1]->rbfa[j];
-			double		rad1 = R2ANG(rbf1j->crad);
-			FVECT		v;
-			int		pos[2];
-			rbf->rbfa[n].peak = peak0 * mv * rbf->vtotal;
-			rbf->rbfa[n].crad = ANG2R(sqrt(rad0*rad0*(1.-t) +
-							rad1*rad1*t));
-			ovec_from_pos(v, rbf1j->gx, rbf1j->gy);
-			geodesic(v, v0, v, t, GEOD_REL);
-			pos_from_vec(pos, v);
-			rbf->rbfa[n].gx = pos[0];
-			rbf->rbfa[n].gy = pos[1];
-			++n;
-		}
-	}
-	rbf->vtotal *= mig->rbfv[0]->vtotal;	/* turn ratio into actual */
-	return(rbf);
-memerr:
-	fprintf(stderr, "%s: Out of memory in e_advect_rbf()\n", progname);
-	exit(1);
-	return(NULL);	/* pro forma return */
-}
-
-/* Partially advect between recorded incident angles and allocate new RBF */
+/* Advect between recorded incident angles and allocate new RBF */
 RBFNODE *
-advect_rbf(const FVECT invec)
+advect_rbf(const FVECT invec, int lobe_lim)
 {
+	double		cthresh = FTINY;
 	FVECT		sivec;
 	MIGRATION	*miga[3];
 	RBFNODE		*rbf;
@@ -302,16 +280,19 @@ advect_rbf(const FVECT invec)
 	VCOPY(sivec, invec);			/* find triangle/edge */
 	sym = get_interp(miga, sivec);
 	if (sym < 0)				/* can't interpolate? */
-		return(NULL);
+		return(def_rbf_spec(invec));
 	if (miga[1] == NULL) {			/* advect along edge? */
-		rbf = e_advect_rbf(miga[0], sivec);
-		rev_rbf_symmetry(rbf, sym);
+		rbf = e_advect_rbf(miga[0], sivec, lobe_lim);
+		if (single_plane_incident)
+			rotate_rbf(rbf, invec);
+		else
+			rev_rbf_symmetry(rbf, sym);
 		return(rbf);
 	}
 #ifdef DEBUG
-	if (miga[0]->rbfv[0] != miga[2]->rbfv[0] |
-			miga[0]->rbfv[1] != miga[1]->rbfv[0] |
-			miga[1]->rbfv[1] != miga[2]->rbfv[1]) {
+	if ((miga[0]->rbfv[0] != miga[2]->rbfv[0]) |
+			(miga[0]->rbfv[1] != miga[1]->rbfv[0]) |
+			(miga[1]->rbfv[1] != miga[2]->rbfv[1])) {
 		fprintf(stderr, "%s: Triangle vertex screw-up!\n", progname);
 		exit(1);
 	}
@@ -327,13 +308,19 @@ advect_rbf(const FVECT invec)
 	geodesic(v1, miga[0]->rbfv[0]->invec, miga[0]->rbfv[1]->invec,
 			s, GEOD_REL);
 	t = acos(DOT(v1,sivec)) / acos(DOT(v1,miga[1]->rbfv[1]->invec));
+tryagain:
 	n = 0;					/* count migrating particles */
 	for (i = 0; i < mtx_nrows(miga[0]); i++)
 	    for (j = 0; j < mtx_ncols(miga[0]); j++)
-		for (k = (mtx_coef(miga[0],i,j) > FTINY) *
+		for (k = (mtx_coef(miga[0],i,j) > cthresh) *
 					mtx_ncols(miga[2]); k--; )
-			n += (mtx_coef(miga[2],i,k) > FTINY &&
-				mtx_coef(miga[1],j,k) > FTINY);
+			n += (mtx_coef(miga[2],i,k) > cthresh ||
+				mtx_coef(miga[1],j,k) > cthresh);
+						/* are we over our limit? */
+	if ((lobe_lim > 0) & (n > lobe_lim)) {
+		cthresh = cthresh*2. + 10.*FTINY;
+		goto tryagain;
+	}
 #ifdef DEBUG
 	fprintf(stderr, "Input RBFs have %d, %d, %d nodes -> output has %d\n",
 			miga[0]->rbfv[0]->nrbf, miga[0]->rbfv[1]->nrbf,
@@ -360,30 +347,31 @@ advect_rbf(const FVECT invec)
 	    for (j = 0; j < mtx_ncols(miga[0]); j++) {
 		const float	ma = mtx_coef(miga[0],i,j);
 		const RBFVAL	*rbf1j;
-		double		rad1j, srad2;
-		if (ma <= FTINY)
+		double		srad2;
+		if (ma <= cthresh)
 			continue;
 		rbf1j = &miga[0]->rbfv[1]->rbfa[j];
-		rad1j = R2ANG(rbf1j->crad);
-		srad2 = (1.-s)*(1.-t)*rad0i*rad0i + s*(1.-t)*rad1j*rad1j;
+		srad2 = R2ANG(rbf1j->crad);
+		srad2 = (1.-s)*(1.-t)*rad0i*rad0i + s*(1.-t)*srad2*srad2;
 		ovec_from_pos(v1, rbf1j->gx, rbf1j->gy);
 		geodesic(v1, v0, v1, s, GEOD_REL);
 		for (k = 0; k < mtx_ncols(miga[2]); k++) {
 		    float		mb = mtx_coef(miga[1],j,k);
 		    float		mc = mtx_coef(miga[2],i,k);
 		    const RBFVAL	*rbf2k;
-		    double		rad2k;
-		    FVECT		vout;
+		    double		rad2;
 		    int			pos[2];
-		    if ((mb <= FTINY) | (mc <= FTINY))
+		    if ((mb <= cthresh) & (mc <= cthresh))
 			continue;
 		    rbf2k = &miga[2]->rbfv[1]->rbfa[k];
-		    rbf->rbfa[n].peak = w0i * ma * (mb*mbfact + mc*mcfact);
-		    rad2k = R2ANG(rbf2k->crad);
-		    rbf->rbfa[n].crad = ANG2R(sqrt(srad2 + t*rad2k*rad2k));
+		    rad2 = R2ANG(rbf2k->crad);
+		    rad2 = srad2 + t*rad2*rad2;
+		    rbf->rbfa[n].peak = w0i * ma * (mb*mbfact + mc*mcfact) *
+					rad0i*rad0i/rad2;
+		    rbf->rbfa[n].crad = ANG2R(sqrt(rad2));
 		    ovec_from_pos(v2, rbf2k->gx, rbf2k->gy);
-		    geodesic(vout, v1, v2, t, GEOD_REL);
-		    pos_from_vec(pos, vout);
+		    geodesic(v2, v1, v2, t, GEOD_REL);
+		    pos_from_vec(pos, v2);
 		    rbf->rbfa[n].gx = pos[0];
 		    rbf->rbfa[n].gy = pos[1];
 		    ++n;