--- ray/src/rt/m_brdf.c	2003/02/22 02:07:28	2.15
+++ ray/src/rt/m_brdf.c	2003/03/05 16:16:53	2.18
@@ -1,66 +1,11 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: m_brdf.c,v 2.15 2003/02/22 02:07:28 greg Exp $";
+static const char	RCSid[] = "$Id: m_brdf.c,v 2.18 2003/03/05 16:16:53 greg Exp $";
 #endif
 /*
  *  Shading for materials with arbitrary BRDF's
  */
 
-/* ====================================================================
- * The Radiance Software License, Version 1.0
- *
- * Copyright (c) 1990 - 2002 The Regents of the University of California,
- * through Lawrence Berkeley National Laboratory.   All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *         notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in
- *       the documentation and/or other materials provided with the
- *       distribution.
- *
- * 3. The end-user documentation included with the redistribution,
- *           if any, must include the following acknowledgment:
- *             "This product includes Radiance software
- *                 (http://radsite.lbl.gov/)
- *                 developed by the Lawrence Berkeley National Laboratory
- *               (http://www.lbl.gov/)."
- *       Alternately, this acknowledgment may appear in the software itself,
- *       if and wherever such third-party acknowledgments normally appear.
- *
- * 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
- *       and "The Regents of the University of California" must
- *       not be used to endorse or promote products derived from this
- *       software without prior written permission. For written
- *       permission, please contact radiance@radsite.lbl.gov.
- *
- * 5. Products derived from this software may not be called "Radiance",
- *       nor may "Radiance" appear in their name, without prior written
- *       permission of Lawrence Berkeley National Laboratory.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED.   IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of Lawrence Berkeley National Laboratory.   For more
- * information on Lawrence Berkeley National Laboratory, please see
- * <http://www.lbl.gov/>.
- */
+#include "copyright.h"
 
 #include  "ray.h"
 
@@ -215,7 +160,7 @@ double  omega;			/* light source size */
 		dtmp = funvalue(sa[0], 5, vldx);
 		setcolor(ctmp, dtmp, dtmp, dtmp);
 	}
-	if (errno) {
+	if (errno == EDOM || errno == ERANGE) {
 		objerror(np->mp, WARNING, "compute error");
 		return;
 	}
@@ -279,7 +224,7 @@ register RAY  *r;
 	setcolor(nd.tdiff, m->oargs.farg[6],
 			m->oargs.farg[7],
 			m->oargs.farg[8]);
-					/* get modifiers */
+						/* get modifiers */
 	raytexture(r, m->omod);
 	nd.pdot = raynormal(nd.pnorm, r);	/* perturb normal */
 	if (r->rod < 0.0) {			/* orient perturbed values */
@@ -306,7 +251,7 @@ register RAY  *r;
 	setcolor(ctmp, evalue(mf->ep[3]),
 			evalue(mf->ep[4]),
 			evalue(mf->ep[5]));
-	if (errno)
+	if (errno == EDOM || errno == ERANGE)
 		objerror(m, WARNING, "compute error");
 	else if (rayorigin(&sr, r, TRANS, bright(ctmp)) == 0) {
 		if (!(r->crtype & SHADOW) &&
@@ -335,7 +280,7 @@ register RAY  *r;
 	setcolor(ctmp, evalue(mf->ep[0]),
 			evalue(mf->ep[1]),
 			evalue(mf->ep[2]));
-	if (errno)
+	if (errno == EDOM || errno == ERANGE)
 		objerror(m, WARNING, "compute error");
 	else if (rayorigin(&sr, r, REFLECTED, bright(ctmp)) == 0) {
 		for (i = 0; i < 3; i++)
@@ -393,6 +338,18 @@ register RAY  *r;
 	if (m->oargs.nsargs < (hasdata(m->otype)?4:2) | m->oargs.nfargs <
 			(m->otype==MAT_TFUNC|m->otype==MAT_TDATA?6:4))
 		objerror(m, USER, "bad # arguments");
+						/* check for back side */
+	if (r->rod < 0.0) {
+		if (!backvis && m->otype != MAT_TFUNC
+				&& m->otype != MAT_TDATA) {
+			raytrans(r);
+			return(1);
+		}
+		raytexture(r, m->omod);
+		flipsurface(r);			/* reorient if backvis */
+	} else
+		raytexture(r, m->omod);
+
 	nd.mp = m;
 	nd.pr = r;
 						/* get material color */
@@ -414,17 +371,6 @@ register RAY  *r;
 						/* compute reflectance */
 	dtmp = 1.0 - nd.trans - nd.rspec;
 	setcolor(nd.rdiff, dtmp, dtmp, dtmp);
-						/* check for back side */
-	if (r->rod < 0.0) {
-		if (!backvis && m->otype != MAT_TFUNC
-				&& m->otype != MAT_TDATA) {
-			raytrans(r);
-			return(1);
-		}
-		flipsurface(r);			/* reorient if backvis */
-	}
-						/* get modifiers */
-	raytexture(r, m->omod);
 	nd.pdot = raynormal(nd.pnorm, r);	/* perturb normal */
 	multcolor(nd.mcolor, r->pcol);		/* modify material color */
 	multcolor(nd.rdiff, nd.mcolor);