--- ray/src/rt/aniso.c	2012/07/29 19:01:39	2.54
+++ ray/src/rt/aniso.c	2014/12/04 05:26:28	2.57
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: aniso.c,v 2.54 2012/07/29 19:01:39 greg Exp $";
+static const char RCSid[] = "$Id: aniso.c,v 2.57 2014/12/04 05:26:28 greg Exp $";
 #endif
 /*
  *  Shading functions for anisotropic materials.
@@ -41,7 +41,6 @@ static const char RCSid[] = "$Id: aniso.c,v 2.54 2012/
 #define  SP_FLAT	04		/* reflecting surface is flat */
 #define  SP_RBLT	010		/* reflection below sample threshold */
 #define  SP_TBLT	020		/* transmission below threshold */
-#define  SP_BADU	040		/* bad u direction calculation */
 
 typedef struct {
 	OBJREC  *mp;		/* material pointer */
@@ -61,8 +60,8 @@ typedef struct {
 	double  pdot;		/* perturbed dot product */
 }  ANISODAT;		/* anisotropic material data */
 
-static void getacoords(RAY  *r, ANISODAT  *np);
-static void agaussamp(RAY  *r, ANISODAT  *np);
+static void getacoords(ANISODAT  *np);
+static void agaussamp(ANISODAT  *np);
 
 
 static void
@@ -98,7 +97,7 @@ diraniso(		/* compute source contribution */
 		scalecolor(ctmp, dtmp);
 		addcolor(cval, ctmp);
 	}
-	if (ldot > FTINY && (np->specfl&(SP_REFL|SP_BADU)) == SP_REFL) {
+	if (ldot > FTINY && np->specfl&SP_REFL) {
 		/*
 		 *  Compute specular reflection coefficient using
 		 *  anisotropic Gaussian distribution model.
@@ -140,7 +139,7 @@ diraniso(		/* compute source contribution */
 		scalecolor(ctmp, dtmp);
 		addcolor(cval, ctmp);
 	}
-	if (ldot < -FTINY && (np->specfl&(SP_TRAN|SP_BADU)) == SP_TRAN) {
+	if (ldot < -FTINY && np->specfl&SP_TRAN) {
 		/*
 		 *  Compute specular transmission.  Specular transmission
 		 *  is always modified by material color.
@@ -194,7 +193,7 @@ m_aniso(			/* shade ray that hit something anisotropic
 		objerror(m, USER, "bad number of real arguments");
 						/* check for back side */
 	if (r->rod < 0.0) {
-		if (!backvis && m->otype != MAT_TRANS2) {
+		if (!backvis) {
 			raytrans(r);
 			return(1);
 		}
@@ -266,10 +265,10 @@ m_aniso(			/* shade ray that hit something anisotropic
 	if (r->ro != NULL && isflat(r->ro->otype))
 		nd.specfl |= SP_FLAT;
 
-	getacoords(r, &nd);			/* set up coordinates */
+	getacoords(&nd);			/* set up coordinates */
 
-	if (nd.specfl & (SP_REFL|SP_TRAN) && !(nd.specfl & SP_BADU))
-		agaussamp(r, &nd);
+	if (nd.specfl & (SP_REFL|SP_TRAN))
+		agaussamp(&nd);
 
 	if (nd.rdiff > FTINY) {		/* ambient from this side */
 		copycolor(ctmp, nd.mcolor);	/* modified by material color */
@@ -304,7 +303,6 @@ m_aniso(			/* shade ray that hit something anisotropic
 
 static void
 getacoords(		/* set up coordinate system */
-	RAY  *r,
 	ANISODAT  *np
 )
 {
@@ -312,30 +310,29 @@ getacoords(		/* set up coordinate system */
 	int  i;
 
 	mf = getfunc(np->mp, 3, 0x7, 1);
-	setfunc(np->mp, r);
+	setfunc(np->mp, np->rp);
 	errno = 0;
 	for (i = 0; i < 3; i++)
 		np->u[i] = evalue(mf->ep[i]);
-	if ((errno == EDOM) | (errno == ERANGE)) {
-		objerror(np->mp, WARNING, "compute error");
-		np->specfl |= SP_BADU;
-		return;
-	}
+	if ((errno == EDOM) | (errno == ERANGE))
+		np->u[0] = np->u[1] = np->u[2] = 0.0;
 	if (mf->fxp != &unitxf)
 		multv3(np->u, np->u, mf->fxp->xfm);
 	fcross(np->v, np->pnorm, np->u);
 	if (normalize(np->v) == 0.0) {
-		objerror(np->mp, WARNING, "illegal orientation vector");
-		np->specfl |= SP_BADU;
-		return;
-	}
-	fcross(np->u, np->v, np->pnorm);
+		if (fabs(np->u_alpha - np->v_alpha) > 0.001)
+			objerror(np->mp, WARNING, "illegal orientation vector");
+		getperpendicular(np->u, np->pnorm);	/* punting */
+		fcross(np->v, np->pnorm, np->u);
+		np->u_alpha = np->v_alpha = sqrt( 0.5 *
+			(np->u_alpha*np->u_alpha + np->v_alpha*np->v_alpha) );
+	} else
+		fcross(np->u, np->v, np->pnorm);
 }
 
 
 static void
 agaussamp(		/* sample anisotropic Gaussian specular */
-	RAY  *r,
 	ANISODAT  *np
 )
 {
@@ -348,10 +345,10 @@ agaussamp(		/* sample anisotropic Gaussian specular */
 	int  i;
 					/* compute reflection */
 	if ((np->specfl & (SP_REFL|SP_RBLT)) == SP_REFL &&
-			rayorigin(&sr, SPECULAR, r, np->scolor) == 0) {
+			rayorigin(&sr, SPECULAR, np->rp, np->scolor) == 0) {
 		nstarget = 1;
 		if (specjitter > 1.5) {	/* multiple samples? */
-			nstarget = specjitter*r->rweight + .5;
+			nstarget = specjitter*np->rp->rweight + .5;
 			if (sr.rweight <= minweight*nstarget)
 				nstarget = sr.rweight/minweight;
 			if (nstarget > 1) {
@@ -388,22 +385,22 @@ agaussamp(		/* sample anisotropic Gaussian specular */
 			for (i = 0; i < 3; i++)
 				h[i] = np->pnorm[i] +
 					d*(cosp*np->u[i] + sinp*np->v[i]);
-			d = -2.0 * DOT(h, r->rdir) / (1.0 + d*d);
-			VSUM(sr.rdir, r->rdir, h, d);
+			d = -2.0 * DOT(h, np->rp->rdir) / (1.0 + d*d);
+			VSUM(sr.rdir, np->rp->rdir, h, d);
 						/* sample rejection test */
-			if ((d = DOT(sr.rdir, r->ron)) <= FTINY)
+			if ((d = DOT(sr.rdir, np->rp->ron)) <= FTINY)
 				continue;
 			checknorm(sr.rdir);
 			if (nstarget > 1) {	/* W-G-M-D adjustment */
 				if (nstaken) rayclear(&sr);
 				rayvalue(&sr);
-				d = 2./(1. + r->rod/d);
+				d = 2./(1. + np->rp->rod/d);
 				scalecolor(sr.rcol, d);
 				addcolor(scol, sr.rcol);
 			} else {
 				rayvalue(&sr);
 				multcolor(sr.rcol, sr.rcoef);
-				addcolor(r->rcol, sr.rcol);
+				addcolor(np->rp->rcol, sr.rcol);
 			}
 			++nstaken;
 		}
@@ -411,7 +408,7 @@ agaussamp(		/* sample anisotropic Gaussian specular */
 			multcolor(scol, sr.rcoef);
 			d = (double)nstarget/ntrials;
 			scalecolor(scol, d);
-			addcolor(r->rcol, scol);
+			addcolor(np->rp->rcol, scol);
 		}
 		ndims--;
 	}
@@ -419,10 +416,10 @@ agaussamp(		/* sample anisotropic Gaussian specular */
 	copycolor(sr.rcoef, np->mcolor);		/* modify by material color */
 	scalecolor(sr.rcoef, np->tspec);
 	if ((np->specfl & (SP_TRAN|SP_TBLT)) == SP_TRAN &&
-			rayorigin(&sr, SPECULAR, r, sr.rcoef) == 0) {
+			rayorigin(&sr, SPECULAR, np->rp, sr.rcoef) == 0) {
 		nstarget = 1;
 		if (specjitter > 1.5) {	/* multiple samples? */
-			nstarget = specjitter*r->rweight + .5;
+			nstarget = specjitter*np->rp->rweight + .5;
 			if (sr.rweight <= minweight*nstarget)
 				nstarget = sr.rweight/minweight;
 			if (nstarget > 1) {
@@ -458,14 +455,14 @@ agaussamp(		/* sample anisotropic Gaussian specular */
 			for (i = 0; i < 3; i++)
 				sr.rdir[i] = np->prdir[i] +
 						d*(cosp*np->u[i] + sinp*np->v[i]);
-			if (DOT(sr.rdir, r->ron) >= -FTINY)
+			if (DOT(sr.rdir, np->rp->ron) >= -FTINY)
 				continue;
 			normalize(sr.rdir);	/* OK, normalize */
 			if (nstaken)		/* multi-sampling */
 				rayclear(&sr);
 			rayvalue(&sr);
 			multcolor(sr.rcol, sr.rcoef);
-			addcolor(r->rcol, sr.rcol);
+			addcolor(np->rp->rcol, sr.rcol);
 			++nstaken;
 		}
 		ndims--;