--- ray/src/rt/aniso.c	2003/02/25 02:47:22	2.35
+++ ray/src/rt/aniso.c	2004/09/20 17:32:04	2.42
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: aniso.c,v 2.35 2003/02/25 02:47:22 greg Exp $";
+static const char RCSid[] = "$Id: aniso.c,v 2.42 2004/09/20 17:32:04 greg Exp $";
 #endif
 /*
  *  Shading functions for anisotropic materials.
@@ -8,11 +8,11 @@ static const char	RCSid[] = "$Id: aniso.c,v 2.35 2003/
 #include "copyright.h"
 
 #include  "ray.h"
-
+#include  "ambient.h"
 #include  "otypes.h"
-
+#include  "rtotypes.h"
+#include  "source.h"
 #include  "func.h"
-
 #include  "random.h"
 
 #ifndef  MAXITER
@@ -60,17 +60,20 @@ typedef struct {
 	double  pdot;		/* perturbed dot product */
 }  ANISODAT;		/* anisotropic material data */
 
-static void	getacoords();
-static void	agaussamp();
+static srcdirf_t diraniso;
+static void getacoords(RAY  *r, ANISODAT  *np);
+static void agaussamp(RAY  *r, ANISODAT  *np);
 
 
 static void
-diraniso(cval, np, ldir, omega)		/* compute source contribution */
-COLOR  cval;			/* returned coefficient */
-register ANISODAT  *np;		/* material data */
-FVECT  ldir;			/* light source direction */
-double  omega;			/* light source size */
+diraniso(		/* compute source contribution */
+	COLOR  cval,			/* returned coefficient */
+	void  *nnp,		/* material data */
+	FVECT  ldir,			/* light source direction */
+	double  omega			/* light source size */
+)
 {
+	register ANISODAT *np = nnp;
 	double  ldot;
 	double  dtmp, dtmp1, dtmp2;
 	FVECT  h;
@@ -91,7 +94,7 @@ double  omega;			/* light source size */
 		 *  modified by the color of the material.
 		 */
 		copycolor(ctmp, np->mcolor);
-		dtmp = ldot * omega * np->rdiff / PI;
+		dtmp = ldot * omega * np->rdiff * (1.0/PI);
 		scalecolor(ctmp, dtmp);
 		addcolor(cval, ctmp);
 	}
@@ -102,7 +105,7 @@ double  omega;			/* light source size */
 		 */
 						/* add source width if flat */
 		if (np->specfl & SP_FLAT)
-			au2 = av2 = omega/(4.0*PI);
+			au2 = av2 = omega * (0.25/PI);
 		else
 			au2 = av2 = 0.0;
 		au2 += np->u_alpha*np->u_alpha;
@@ -119,8 +122,7 @@ double  omega;			/* light source size */
 						/* gaussian */
 		dtmp = DOT(np->pnorm, h);
 		dtmp = (dtmp1 + dtmp2) / (dtmp*dtmp);
-		dtmp = exp(-dtmp) * (0.25/PI)
-				* sqrt(ldot/(np->pdot*au2*av2));
+		dtmp = exp(-dtmp) / (4.0*PI * np->pdot * sqrt(au2*av2));
 						/* worth using? */
 		if (dtmp > FTINY) {
 			copycolor(ctmp, np->scolor);
@@ -134,7 +136,7 @@ double  omega;			/* light source size */
 		 *  Compute diffuse transmission.
 		 */
 		copycolor(ctmp, np->mcolor);
-		dtmp = -ldot * omega * np->tdiff / PI;
+		dtmp = -ldot * omega * np->tdiff * (1.0/PI);
 		scalecolor(ctmp, dtmp);
 		addcolor(cval, ctmp);
 	}
@@ -144,7 +146,7 @@ double  omega;			/* light source size */
 		 *  is always modified by material color.
 		 */
 						/* roughness + source */
-		au2 = av2 = omega / PI;
+		au2 = av2 = omega * (1.0/PI);
 		au2 += np->u_alpha*np->u_alpha;
 		av2 += np->v_alpha*np->v_alpha;
 						/* "half vector" */
@@ -165,8 +167,7 @@ double  omega;			/* light source size */
 		} else
 			dtmp = 0.0;
 						/* gaussian */
-		dtmp = exp(-dtmp) * (1.0/PI)
-				* sqrt(-ldot/(np->pdot*au2*av2));
+		dtmp = exp(-dtmp) / (PI * np->pdot * sqrt(au2*av2));
 						/* worth using? */
 		if (dtmp > FTINY) {
 			copycolor(ctmp, np->mcolor);
@@ -178,10 +179,11 @@ double  omega;			/* light source size */
 }
 
 
-int
-m_aniso(m, r)			/* shade ray that hit something anisotropic */
-register OBJREC  *m;
-register RAY  *r;
+extern int
+m_aniso(			/* shade ray that hit something anisotropic */
+	register OBJREC  *m,
+	register RAY  *r
+)
 {
 	ANISODAT  nd;
 	COLOR  ctmp;
@@ -192,9 +194,19 @@ register RAY  *r;
 
 	if (m->oargs.nfargs != (m->otype == MAT_TRANS2 ? 8 : 6))
 		objerror(m, USER, "bad number of real arguments");
+						/* check for back side */
+	if (r->rod < 0.0) {
+		if (!backvis && m->otype != MAT_TRANS2) {
+			raytrans(r);
+			return(1);
+		}
+		raytexture(r, m->omod);
+		flipsurface(r);			/* reorient if backvis */
+	} else
+		raytexture(r, m->omod);
+						/* get material color */
 	nd.mp = m;
 	nd.rp = r;
-						/* get material color */
 	setcolor(nd.mcolor, m->oargs.farg[0],
 			   m->oargs.farg[1],
 			   m->oargs.farg[2]);
@@ -204,16 +216,7 @@ register RAY  *r;
 	nd.v_alpha = m->oargs.farg[5];
 	if (nd.u_alpha < FTINY || nd.v_alpha <= FTINY)
 		objerror(m, USER, "roughness too small");
-						/* check for back side */
-	if (r->rod < 0.0) {
-		if (!backvis && m->otype != MAT_TRANS2) {
-			raytrans(r);
-			return(1);
-		}
-		flipsurface(r);			/* reorient if backvis */
-	}
-						/* get modifiers */
-	raytexture(r, m->omod);
+
 	nd.pdot = raynormal(nd.pnorm, r);	/* perturb normal */
 	if (nd.pdot < .001)
 		nd.pdot = .001;			/* non-zero for diraniso() */
@@ -305,9 +308,10 @@ register RAY  *r;
 
 
 static void
-getacoords(r, np)		/* set up coordinate system */
-RAY  *r;
-register ANISODAT  *np;
+getacoords(		/* set up coordinate system */
+	RAY  *r,
+	register ANISODAT  *np
+)
 {
 	register MFUNC  *mf;
 	register int  i;
@@ -317,7 +321,7 @@ register ANISODAT  *np;
 	errno = 0;
 	for (i = 0; i < 3; i++)
 		np->u[i] = evalue(mf->ep[i]);
-	if (errno) {
+	if (errno == EDOM || errno == ERANGE) {
 		objerror(np->mp, WARNING, "compute error");
 		np->specfl |= SP_BADU;
 		return;
@@ -335,9 +339,10 @@ register ANISODAT  *np;
 
 
 static void
-agaussamp(r, np)		/* sample anisotropic gaussian specular */
-RAY  *r;
-register ANISODAT  *np;
+agaussamp(		/* sample anisotropic gaussian specular */
+	RAY  *r,
+	register ANISODAT  *np
+)
 {
 	RAY  sr;
 	FVECT  h;