--- ray/src/rt/m_brdf.c	1991/06/18 08:59:55	1.11
+++ ray/src/rt/m_brdf.c	1992/10/14 12:30:54	2.4
@@ -14,6 +14,8 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #include  "otypes.h"
 
+#include  "func.h"
+
 /*
  *	Arguments to this material include the color and specularity.
  *  String arguments include the reflection function and files.
@@ -58,9 +60,6 @@ static char SCCSid[] = "$SunId$ LBL";
  *		CrP, CgP, CbP -		perturbed material color
  */
 
-extern double	funvalue(), varvalue();
-extern XF  funcxf;
-
 typedef struct {
 	OBJREC  *mp;		/* material pointer */
 	RAY  *pr;		/* intersected ray */
@@ -86,7 +85,7 @@ double  omega;			/* light source size */
 	double  dtmp;
 	COLOR  ctmp;
 	FVECT  ldx;
-	double  pt[MAXDIM];
+	double  lddx[3], pt[MAXDIM];
 	register char	**sa;
 	register int	i;
 
@@ -128,33 +127,35 @@ double  omega;			/* light source size */
 					/* transform light vector */
 	multv3(ldx, ldir, funcxf.xfm);
 	for (i = 0; i < 3; i++)
-		ldx[i] /= funcxf.sca;
+		lddx[i] = ldx[i]/funcxf.sca;
 					/* compute BRTDF */
 	if (np->mp->otype == MAT_BRTDF) {
-		colval(ctmp,RED) = funvalue(sa[6], 3, ldx);
+		colval(ctmp,RED) = funvalue(sa[6], 3, lddx);
 		if (!strcmp(sa[7],sa[6]))
 			colval(ctmp,GRN) = colval(ctmp,RED);
 		else
-			colval(ctmp,GRN) = funvalue(sa[7], 3, ldx);
+			colval(ctmp,GRN) = funvalue(sa[7], 3, lddx);
 		if (!strcmp(sa[8],sa[6]))
 			colval(ctmp,BLU) = colval(ctmp,RED);
 		else if (!strcmp(sa[8],sa[7]))
 			colval(ctmp,BLU) = colval(ctmp,GRN);
 		else
-			colval(ctmp,BLU) = funvalue(sa[8], 3, ldx);
+			colval(ctmp,BLU) = funvalue(sa[8], 3, lddx);
 		dtmp = bright(ctmp);
 	} else if (np->dp == NULL) {
-		dtmp = funvalue(sa[0], 3, ldx);
+		dtmp = funvalue(sa[0], 3, lddx);
 		setcolor(ctmp, dtmp, dtmp, dtmp);
 	} else {
 		for (i = 0; i < np->dp->nd; i++)
-			pt[i] = funvalue(sa[3+i], 3, ldx);
+			pt[i] = funvalue(sa[3+i], 3, lddx);
 		dtmp = datavalue(np->dp, pt);
 		dtmp = funvalue(sa[0], 1, &dtmp);
 		setcolor(ctmp, dtmp, dtmp, dtmp);
 	}
-	if (errno)
-		goto computerr;
+	if (errno) {
+		objerror(np->mp, WARNING, "compute error");
+		return;
+	}
 	if (dtmp <= FTINY)
 		return;
 	if (ldot > 0.0) {
@@ -176,10 +177,6 @@ double  omega;			/* light source size */
 		scalecolor(ctmp, dtmp);
 		addcolor(cval, ctmp);
 	}
-	return;
-computerr:
-	objerror(np->mp, WARNING, "compute error");
-	return;
 }
 
 
@@ -191,7 +188,8 @@ register RAY  *r;
 	BRDFDAT  nd;
 	double  transtest, transdist;
 	COLOR  ctmp;
-	double  dtmp;
+	double  dtmp, tspect, rspecr;
+	MFUNC  *mf;
 	register int  i;
 						/* check arguments */
 	switch (m->otype) {
@@ -238,44 +236,41 @@ register RAY  *r;
 	multcolor(nd.mcolor, r->pcol);		/* modify material color */
 	transtest = 0;
 						/* load auxiliary files */
-	if (m->otype == MAT_PDATA || m->otype == MAT_MDATA
-			|| m->otype == MAT_TDATA) {
+	if (hasdata(m->otype)) {
 		nd.dp = getdata(m->oargs.sarg[1]);
-		for (i = 3; i < m->oargs.nsargs; i++)
-			if (m->oargs.sarg[i][0] == '-')
-				break;
-		if (i-3 != nd.dp->nd)
-			objerror(m, USER, "dimension error");
-		if (!fundefined(m->oargs.sarg[3]))
-			loadfunc(m->oargs.sarg[2]);
+		i = (1 << nd.dp->nd) - 1;
+		mf = getfunc(m, 2, i<<3, 0);
 	} else if (m->otype == MAT_BRTDF) {
 		nd.dp = NULL;
-		if (!fundefined(m->oargs.sarg[7]))
-			loadfunc(m->oargs.sarg[9]);
+		mf = getfunc(m, 9, 0x3f, 0);
 	} else {
 		nd.dp = NULL;
-		if (!fundefined(m->oargs.sarg[0]))
-			loadfunc(m->oargs.sarg[1]);
+		mf = getfunc(m, 1, 0, 0);
 	}
 						/* set special variables */
 	setbrdfunc(&nd);
 						/* compute transmitted ray */
+	tspect = 0.;
 	if (m->otype == MAT_BRTDF && nd.tspec > FTINY) {
 		RAY  sr;
 		errno = 0;
-		setcolor(ctmp, varvalue(m->oargs.sarg[0]),
-				varvalue(m->oargs.sarg[1]),
-				varvalue(m->oargs.sarg[2]));
-		scalecolor(ctmp, nd.tspec);
+		setcolor(ctmp, evalue(mf->ep[3]),
+				evalue(mf->ep[4]),
+				evalue(mf->ep[5]));
+		scalecolor(ctmp, nd.trans);
 		if (errno)
 			objerror(m, WARNING, "compute error");
-		else if ((dtmp = bright(ctmp)) > FTINY &&
-				rayorigin(&sr, r, TRANS, dtmp) == 0) {
-			if (DOT(r->pert,r->pert) > FTINY*FTINY) {
+		else if ((tspect = bright(ctmp)) > FTINY &&
+				rayorigin(&sr, r, TRANS, tspect) == 0) {
+			if (!(r->crtype & SHADOW) &&
+					DOT(r->pert,r->pert) > FTINY*FTINY) {
 				for (i = 0; i < 3; i++)	/* perturb direction */
 					sr.rdir[i] = r->rdir[i] -
 							.75*r->pert[i];
-				normalize(sr.rdir);
+				if (normalize(sr.rdir) == 0.0) {
+					objerror(m, WARNING, "illegal perturbation");
+					VCOPY(sr.rdir, r->rdir);
+				}
 			} else {
 				VCOPY(sr.rdir, r->rdir);
 				transtest = 2;
@@ -290,17 +285,17 @@ register RAY  *r;
 	if (r->crtype & SHADOW)			/* the rest is shadow */
 		return;
 						/* compute reflected ray */
+	rspecr = 0.;
 	if (m->otype == MAT_BRTDF && nd.rspec > FTINY) {
 		RAY  sr;
 		errno = 0;
-		setcolor(ctmp, varvalue(m->oargs.sarg[3]),
-				varvalue(m->oargs.sarg[4]),
-				varvalue(m->oargs.sarg[5]));
-		scalecolor(ctmp, nd.rspec);
+		setcolor(ctmp, evalue(mf->ep[0]),
+				evalue(mf->ep[1]),
+				evalue(mf->ep[2]));
 		if (errno)
 			objerror(m, WARNING, "compute error");
-		else if ((dtmp = bright(ctmp)) > FTINY &&
-				rayorigin(&sr, r, REFLECTED, dtmp) == 0) {
+		else if ((rspecr = bright(ctmp)) > FTINY &&
+				rayorigin(&sr, r, REFLECTED, rspecr) == 0) {
 			for (i = 0; i < 3; i++)
 				sr.rdir[i] = r->rdir[i] +
 						2.0*nd.pdot*nd.pnorm[i];
@@ -310,22 +305,16 @@ register RAY  *r;
 		}
 	}
 						/* compute ambient */
-	if (nd.rdiff > FTINY) {
+	if ((dtmp = 1.0-nd.trans-rspecr) > FTINY) {
 		ambient(ctmp, r);
-		if (m->otype == MAT_BRTDF)
-			scalecolor(ctmp, nd.rdiff);
-		else
-			scalecolor(ctmp, 1.0-nd.trans);
+		scalecolor(ctmp, dtmp);
 		multcolor(ctmp, nd.mcolor);	/* modified by material color */
 		addcolor(r->rcol, ctmp);	/* add to returned color */
 	}
-	if (nd.tdiff > FTINY) {			/* from other side */
+	if ((dtmp = nd.trans-tspect) > FTINY) {	/* from other side */
 		flipsurface(r);
 		ambient(ctmp, r);
-		if (m->otype == MAT_BRTDF)
-			scalecolor(ctmp, nd.tdiff);
-		else
-			scalecolor(ctmp, nd.trans);
+		scalecolor(ctmp, dtmp);
 		multcolor(ctmp, nd.mcolor);
 		addcolor(r->rcol, ctmp);
 		flipsurface(r);