--- ray/src/cv/bsdf2klems.c	2013/06/29 21:03:25	2.6
+++ ray/src/cv/bsdf2klems.c	2013/08/11 14:32:34	2.9
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: bsdf2klems.c,v 2.6 2013/06/29 21:03:25 greg Exp $";
+static const char RCSid[] = "$Id: bsdf2klems.c,v 2.9 2013/08/11 14:32:34 greg Exp $";
 #endif
 /*
  * Load measured BSDF interpolant and write out as XML file with Klems matrix.
@@ -229,12 +229,12 @@ eval_bsdf(const char *fname)
 	    data_epilogue();
 	}
 						/* back transmission */
-	if (bsd.tb != NULL) {
+	if ((bsd.tb != NULL) | (bsd.tf != NULL)) {
 	    input_orient = -1; output_orient = 1;
 	    data_prologue();
 	    for (j = 0; j < abp->nangles; j++) {
 	        for (i = 0; i < abp->nangles; i++) {
-		    sum = 0;			/* average over patches */
+		    sum = 0;		/* average over patches */
 		    for (n = npsamps; n-- > 0; ) {
 			fo_getvec(vout, j+(n+frandom())/npsamps, abp);
 			bi_getvec(vin, i+urand(n), abp);
@@ -261,6 +261,7 @@ static void
 eval_function(char *funame)
 {
 	ANGLE_BASIS	*abp = get_basis(kbasis);
+	int		assignD = (fundefined(funame) < 6);
 	double		iovec[6];
 	double		sum;
 	int		i, j, n;
@@ -281,6 +282,12 @@ eval_function(char *funame)
 		    else
 			bi_getvec(iovec, i+urand(n), abp);
 
+		    if (assignD) {
+			varset("Dx", '=', -iovec[3]);
+			varset("Dy", '=', -iovec[4]);
+			varset("Dz", '=', -iovec[5]);
+			++eclock;
+		    }
 		    sum += funvalue(funame, 6, iovec);
 		}
 		printf("\t%.3e\n", sum/npsamps);
@@ -386,8 +393,11 @@ main(int argc, char *argv[])
 			fprintf(stderr,
 	"%s: need single function with 6 arguments: bsdf(ix,iy,iz,ox,oy,oz)\n",
 					progname);
+			fprintf(stderr, "\tor 3 arguments using Dx,Dy,Dz: bsdf(ix,iy,iz)\n",
+					progname);
 			goto userr;
 		}
+		++eclock;
 		xml_header(argc, argv);			/* start XML output */
 		xml_prologue(NULL);
 		if (dofwd) {