--- ray/src/rt/m_brdf.c	2005/04/19 01:15:06	2.23
+++ ray/src/rt/m_brdf.c	2007/09/07 15:25:01	2.25
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: m_brdf.c,v 2.23 2005/04/19 01:15:06 greg Exp $";
+static const char	RCSid[] = "$Id: m_brdf.c,v 2.25 2007/09/07 15:25:01 greg Exp $";
 #endif
 /*
  *  Shading for materials with arbitrary BRDF's
@@ -129,7 +129,7 @@ dirbrdf(		/* compute source contribution */
 		addcolor(cval, ctmp);
 	}
 	if (ldot > 0.0 ? np->rspec <= FTINY : np->tspec <= FTINY)
-		return;		/* no specular component */
+		return;		/* diffuse only */
 					/* set up function */
 	setbrdfunc(np);
 	sa = np->mp->oargs.sarg;
@@ -145,7 +145,9 @@ dirbrdf(		/* compute source contribution */
 			colval(ctmp,RED) = 0.0;
 		else
 			colval(ctmp,RED) = funvalue(sa[6], 4, lddx);
-		if (!strcmp(sa[7],sa[6]))
+		if (sa[7][0] == '0')
+			colval(ctmp,GRN) = 0.0;
+		else if (!strcmp(sa[7],sa[6]))
 			colval(ctmp,GRN) = colval(ctmp,RED);
 		else
 			colval(ctmp,GRN) = funvalue(sa[7], 4, lddx);
@@ -166,7 +168,7 @@ dirbrdf(		/* compute source contribution */
 		dtmp = funvalue(sa[0], 5, vldx);
 		setcolor(ctmp, dtmp, dtmp, dtmp);
 	}
-	if (errno == EDOM || errno == ERANGE) {
+	if ((errno == EDOM) | (errno == ERANGE)) {
 		objerror(np->mp, WARNING, "compute error");
 		return;
 	}
@@ -265,7 +267,7 @@ m_brdf(			/* color a ray that hit a BRDTfunc material 
 	setcolor(ctmp, evalue(mf->ep[3]),
 			evalue(mf->ep[4]),
 			evalue(mf->ep[5]));
-	if (errno == EDOM || errno == ERANGE)
+	if ((errno == EDOM) | (errno == ERANGE))
 		objerror(m, WARNING, "compute error");
 	else if (rayorigin(&sr, TRANS, r, ctmp) == 0) {
 		if (!(r->crtype & SHADOW) && hastexture) {
@@ -294,7 +296,7 @@ m_brdf(			/* color a ray that hit a BRDTfunc material 
 	setcolor(ctmp, evalue(mf->ep[0]),
 			evalue(mf->ep[1]),
 			evalue(mf->ep[2]));
-	if (errno == EDOM || errno == ERANGE)
+	if ((errno == EDOM) | (errno == ERANGE))
 		objerror(m, WARNING, "compute error");
 	else if (rayorigin(&sr, REFLECTED, r, ctmp) == 0) {
 		for (i = 0; i < 3; i++)