--- ray/src/cv/bsdfinterp.c	2014/03/24 17:22:33	2.18
+++ ray/src/cv/bsdfinterp.c	2021/09/08 01:05:57	2.22
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: bsdfinterp.c,v 2.18 2014/03/24 17:22:33 greg Exp $";
+static const char RCSid[] = "$Id: bsdfinterp.c,v 2.22 2021/09/08 01:05:57 greg Exp $";
 #endif
 /*
  * Interpolate BSDF data from radial basis functions in advection mesh.
@@ -108,8 +108,7 @@ on_edge(const MIGRATION *ej, const FVECT ivec)
 		return(0);
 
 	cos_c = DOT(ej->rbfv[0]->invec, ej->rbfv[1]->invec);
-
-	return(cos_c - cos_aplusb < .001);
+	return(cos_c - cos_aplusb < .0002);
 }
 
 /* Determine if we are inside the given triangle */
@@ -280,7 +279,7 @@ advect_rbf(const FVECT invec, int lobe_lim)
 	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, lobe_lim);
 		if (single_plane_incident)
@@ -343,14 +342,19 @@ tryagain:
 	    const RBFVAL	*rbf0i = &miga[0]->rbfv[0]->rbfa[i];
 	    const float		w0i = rbf0i->peak;
 	    const double	rad0i = R2ANG(rbf0i->crad);
+	    C_COLOR		cc0;
 	    ovec_from_pos(v0, rbf0i->gx, rbf0i->gy);
+	    c_decodeChroma(&cc0, rbf0i->chroma);
 	    for (j = 0; j < mtx_ncols(miga[0]); j++) {
 		const float	ma = mtx_coef(miga[0],i,j);
 		const RBFVAL	*rbf1j;
+		C_COLOR		ccs;
 		double		srad2;
 		if (ma <= cthresh)
 			continue;
 		rbf1j = &miga[0]->rbfv[1]->rbfa[j];
+		c_decodeChroma(&ccs, rbf1j->chroma);
+		c_cmix(&ccs, 1.-s, &cc0, s, &ccs);
 		srad2 = R2ANG(rbf1j->crad);
 		srad2 = (1.-s)*(1.-t)*rad0i*rad0i + s*(1.-t)*srad2*srad2;
 		ovec_from_pos(v1, rbf1j->gx, rbf1j->gy);
@@ -368,6 +372,13 @@ tryagain:
 		    rad2 = srad2 + t*rad2*rad2;
 		    rbf->rbfa[n].peak = w0i * ma * (mb*mbfact + mc*mcfact) *
 					rad0i*rad0i/rad2;
+		    if (rbf_colorimetry == RBCtristimulus) {
+			C_COLOR	cres;
+			c_decodeChroma(&cres, rbf2k->chroma);
+			c_cmix(&cres, 1.-t, &ccs, t, &cres);
+			rbf->rbfa[n].chroma = c_encodeChroma(&cres);
+		    } else
+			rbf->rbfa[n].chroma = c_dfchroma;
 		    rbf->rbfa[n].crad = ANG2R(sqrt(rad2));
 		    ovec_from_pos(v2, rbf2k->gx, rbf2k->gy);
 		    geodesic(v2, v1, v2, t, GEOD_REL);