--- ray/src/rt/normal.c	1992/01/15 11:41:44	2.7
+++ ray/src/rt/normal.c	1992/05/15 13:07:55	2.18
@@ -43,13 +43,14 @@ extern double  specjitter;		/* specular sampling jitte
 				/* specularity flags */
 #define  SP_REFL	01		/* has reflected specular component */
 #define  SP_TRAN	02		/* has transmitted specular */
-#define  SP_PURE	010		/* purely specular (zero roughness) */
-#define  SP_FLAT	020		/* flat reflecting surface */
-#define  SP_RBLT	040		/* reflection below sample threshold */
-#define  SP_TBLT	0100		/* transmission below threshold */
+#define  SP_PURE	04		/* purely specular (zero roughness) */
+#define  SP_FLAT	010		/* flat reflecting surface */
+#define  SP_RBLT	020		/* reflection below sample threshold */
+#define  SP_TBLT	040		/* transmission below threshold */
 
 typedef struct {
 	OBJREC  *mp;		/* material pointer */
+	RAY  *rp;		/* ray pointer */
 	short  specfl;		/* specularity flags, defined above */
 	COLOR  mcolor;		/* color of this material */
 	COLOR  scolor;		/* color of specular component */
@@ -71,8 +72,8 @@ FVECT  ldir;			/* light source direction */
 double  omega;			/* light source size */
 {
 	double  ldot;
-	double  dtmp;
-	int	i;
+	double  dtmp, d2;
+	FVECT  vtmp;
 	COLOR  ctmp;
 
 	setcolor(cval, 0.0, 0.0, 0.0);
@@ -99,16 +100,22 @@ double  omega;			/* light source size */
 		 *  gaussian distribution model.
 		 */
 						/* roughness */
-		dtmp = 2.0*np->alpha2;
+		dtmp = np->alpha2;
 						/* + source if flat */
 		if (np->specfl & SP_FLAT)
-			dtmp += omega/(2.0*PI);
+			dtmp += omega/(4.0*PI);
+						/* delta */
+		vtmp[0] = ldir[0] - np->rp->rdir[0];
+		vtmp[1] = ldir[1] - np->rp->rdir[1];
+		vtmp[2] = ldir[2] - np->rp->rdir[2];
+		d2 = DOT(vtmp, np->pnorm);
+		d2 = 2.0 - 2.0*d2/sqrt(DOT(vtmp,vtmp));
 						/* gaussian */
-		dtmp = exp((DOT(np->vrefl,ldir)-1.)/dtmp)/(2.*PI)/dtmp;
+		dtmp = exp(-d2/dtmp)/(4.*PI*dtmp);
 						/* worth using? */
 		if (dtmp > FTINY) {
 			copycolor(ctmp, np->scolor);
-			dtmp *= omega / np->pdot;
+			dtmp *= omega * sqrt(ldot/np->pdot);
 			scalecolor(ctmp, dtmp);
 			addcolor(cval, ctmp);
 		}
@@ -128,13 +135,13 @@ double  omega;			/* light source size */
 		 *  is always modified by material color.
 		 */
 						/* roughness + source */
-		dtmp = np->alpha2 + omega/(2.0*PI);
+		dtmp = np->alpha2/4.0 + omega/PI;
 						/* gaussian */
-		dtmp = exp((DOT(np->prdir,ldir)-1.)/dtmp)/(2.*PI)/dtmp;
+		dtmp = exp((2.*DOT(np->prdir,ldir)-2.)/dtmp)/(4.*PI*dtmp);
 						/* worth using? */
 		if (dtmp > FTINY) {
 			copycolor(ctmp, np->mcolor);
-			dtmp *= np->tspec * omega / np->pdot;
+			dtmp *= np->tspec * omega * sqrt(-ldot/np->pdot);
 			scalecolor(ctmp, dtmp);
 			addcolor(cval, ctmp);
 		}
@@ -158,6 +165,7 @@ register RAY  *r;
 	if (m->oargs.nfargs != (m->otype == MAT_TRANS ? 7 : 5))
 		objerror(m, USER, "bad number of arguments");
 	nd.mp = m;
+	nd.rp = r;
 						/* get material color */
 	setcolor(nd.mcolor, m->oargs.farg[0],
 			   m->oargs.farg[1],
@@ -192,10 +200,10 @@ register RAY  *r;
 			colval(nd.scolor,i) += (1.0-colval(nd.scolor,i))*dtmp;
 		nd.rspec += (1.0-nd.rspec)*dtmp;
 						/* check threshold */
-		if (specthresh > FTINY &&
-				((specthresh >= 1.-FTINY ||
-				specthresh + (.1 - .2*urand(8199+samplendx))
-					> nd.rspec)))
+		if (!(nd.specfl & SP_PURE) &&
+				specthresh > FTINY &&
+				(specthresh >= 1.-FTINY ||
+				specthresh + .05 - .1*frandom() > nd.rspec))
 			nd.specfl |= SP_RBLT;
 						/* compute reflected ray */
 		for (i = 0; i < 3; i++)
@@ -222,11 +230,9 @@ register RAY  *r;
 		if (nd.tspec > FTINY) {
 			nd.specfl |= SP_TRAN;
 							/* check threshold */
-			if (specthresh > FTINY &&
-					((specthresh >= 1.-FTINY ||
-					specthresh +
-					    (.1 - .2*urand(7241+samplendx))
-						> nd.tspec)))
+			if (!(nd.specfl & SP_PURE) && specthresh > FTINY &&
+					(specthresh >= 1.-FTINY ||
+				specthresh + .05 - .1*frandom() > nd.tspec))
 				nd.specfl |= SP_TBLT;
 			if (r->crtype & SHADOW ||
 					DOT(r->pert,r->pert) <= FTINY*FTINY) {
@@ -235,7 +241,7 @@ register RAY  *r;
 			} else {
 				for (i = 0; i < 3; i++)		/* perturb */
 					nd.prdir[i] = r->rdir[i] -
-							.75*r->pert[i];
+							0.5*r->pert[i];
 				if (DOT(nd.prdir, r->ron) < -FTINY)
 					normalize(nd.prdir);	/* OK */
 				else
@@ -256,7 +262,8 @@ register RAY  *r;
 			transtest *= bright(lr.rcol);
 			transdist = r->rot + lr.rt;
 		}
-	}
+	} else
+		transtest = 0;
 
 	if (r->crtype & SHADOW)			/* the rest is shadow */
 		return;
@@ -266,7 +273,8 @@ register RAY  *r;
 	if (nd.specfl & SP_PURE && nd.rdiff <= FTINY && nd.tdiff <= FTINY)
 		return;				/* 100% pure specular */
 
-	if (r->ro->otype == OBJ_FACE || r->ro->otype == OBJ_RING)
+	if (r->ro != NULL && (r->ro->otype == OBJ_FACE ||
+			r->ro->otype == OBJ_RING))
 		nd.specfl |= SP_FLAT;
 
 	if (nd.specfl & (SP_REFL|SP_TRAN) && !(nd.specfl & SP_PURE))
@@ -310,6 +318,10 @@ register NORMDAT  *np;
 	double  rv[2];
 	double  d, sinp, cosp;
 	register int  i;
+					/* quick test */
+	if ((np->specfl & (SP_REFL|SP_RBLT)) != SP_REFL &&
+			(np->specfl & (SP_TRAN|SP_TBLT)) != SP_TRAN)
+		return;
 					/* set up sample coordinates */
 	v[0] = v[1] = v[2] = 0.0;
 	for (i = 0; i < 3; i++)
@@ -346,4 +358,29 @@ register NORMDAT  *np;
 		ndims--;
 	}
 					/* compute transmission */
+	if ((np->specfl & (SP_TRAN|SP_TBLT)) == SP_TRAN &&
+			rayorigin(&sr, r, SPECULAR, np->tspec) == 0) {
+		dimlist[ndims++] = (int)np->mp;
+		d = urand(ilhash(dimlist,ndims)+1823+samplendx);
+		multisamp(rv, 2, d);
+		d = 2.0*PI * rv[0];
+		cosp = cos(d);
+		sinp = sin(d);
+		rv[1] = 1.0 - specjitter*rv[1];
+		if (rv[1] <= FTINY)
+			d = 1.0;
+		else
+			d = sqrt( np->alpha2/4.0 * -log(rv[1]) );
+		for (i = 0; i < 3; i++)
+			sr.rdir[i] = np->prdir[i] + d*(cosp*u[i] + sinp*v[i]);
+		if (DOT(sr.rdir, r->ron) < -FTINY)
+			normalize(sr.rdir);		/* OK, normalize */
+		else
+			VCOPY(sr.rdir, np->prdir);	/* else no jitter */
+		rayvalue(&sr);
+		scalecolor(sr.rcol, np->tspec);
+		multcolor(sr.rcol, np->mcolor);		/* modified by color */
+		addcolor(r->rcol, sr.rcol);
+		ndims--;
+	}
 }