--- ray/src/rt/m_brdf.c	2005/04/19 01:15:06	2.23
+++ ray/src/rt/m_brdf.c	2012/07/29 21:56:16	2.28
@@ -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 2.28 2012/07/29 21:56:16 greg Exp $";
 #endif
 /*
  *  Shading for materials with arbitrary BRDF's
@@ -77,8 +77,7 @@ typedef struct {
 }  BRDFDAT;		/* BRDF material data */
 
 
-static srcdirf_t dirbrdf;
-static int setbrdfunc(BRDFDAT  *np);
+static int setbrdfunc(BRDFDAT *np);
 
 
 static void
@@ -89,14 +88,14 @@ dirbrdf(		/* compute source contribution */
 	double  omega			/* light source size */
 )
 {
-	register BRDFDAT *np = nnp;
+	BRDFDAT *np = nnp;
 	double  ldot;
 	double  dtmp;
 	COLOR  ctmp;
 	FVECT  ldx;
 	static double  vldx[5], pt[MAXDIM];
-	register char	**sa;
-	register int	i;
+	char	**sa;
+	int	i;
 #define lddx (vldx+1)
 
 	setcolor(cval, 0.0, 0.0, 0.0);
@@ -129,7 +128,7 @@ 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 +144,9 @@ 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 +167,7 @@ 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;
 	}
@@ -195,10 +196,10 @@ dirbrdf(		/* compute source contribution */
 }
 
 
-extern int
+int
 m_brdf(			/* color a ray that hit a BRDTfunc material */
-	register OBJREC  *m,
-	register RAY  *r
+	OBJREC  *m,
+	RAY  *r
 )
 {
 	int  hitfront = 1;
@@ -211,8 +212,8 @@ m_brdf(			/* color a ray that hit a BRDTfunc material 
 	COLOR  ctmp;
 	FVECT  vtmp;
 	double  d;
-	register MFUNC  *mf;
-	register int  i;
+	MFUNC  *mf;
+	int  i;
 						/* check arguments */
 	if ((m->oargs.nsargs < 10) | (m->oargs.nfargs < 9))
 		objerror(m, USER, "bad # arguments");
@@ -265,12 +266,12 @@ 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) {
-			for (i = 0; i < 3; i++)	/* perturb direction */
-				sr.rdir[i] = r->rdir[i] - .75*r->pert[i];
+						/* perturb direction */
+			VSUM(sr.rdir, r->rdir, r->pert, -.75);
 			if (normalize(sr.rdir) == 0.0) {
 				objerror(m, WARNING, "illegal perturbation");
 				VCOPY(sr.rdir, r->rdir);
@@ -294,11 +295,11 @@ 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++)
-			sr.rdir[i] = r->rdir[i] + 2.0*nd.pdot*nd.pnorm[i];
+		VSUM(sr.rdir, r->rdir, nd.pnorm, 2.*nd.pdot);
+		checknorm(sr.rdir);
 		rayvalue(&sr);
 		multcolor(sr.rcol, sr.rcoef);
 		addcolor(r->rcol, sr.rcol);
@@ -343,10 +344,10 @@ m_brdf(			/* color a ray that hit a BRDTfunc material 
 
 
 
-extern int
+int
 m_brdf2(			/* color a ray that hit a BRDF material */
-	register OBJREC  *m,
-	register RAY  *r
+	OBJREC  *m,
+	RAY  *r
 )
 {
 	BRDFDAT  nd;
@@ -432,7 +433,7 @@ m_brdf2(			/* color a ray that hit a BRDF material */
 
 static int
 setbrdfunc(			/* set up brdf function and variables */
-	register BRDFDAT  *np
+	BRDFDAT  *np
 )
 {
 	FVECT  vec;