--- ray/src/gen/mkillum2.c	1991/07/25 12:52:18	1.6
+++ ray/src/gen/mkillum2.c	1992/03/11 12:25:47	2.2
@@ -26,8 +26,7 @@ char  *nm;
 	sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"",
 			nm, ofun[ob->otype].funame, ob->oname);
 	error(WARNING, errmsg);
-	if (!(il->flags & IL_LIGHT))
-		printobj(il->altmat, ob);
+	printobj(il->altmat, ob);
 }
 
 
@@ -38,10 +37,10 @@ struct rtproc  *rt;
 char  *nm;
 {
 #define MAXMISS		(5*n*il->nsamps)
-	int  dim[4];
-	int  n, nalt, nazi;
+	int  dim[3];
+	int  n, nalt, nazi, h;
 	float  *distarr;
-	double  r1, r2;
+	double  sp[2], r1, r2;
 	FVECT  dn, org, dir;
 	FVECT  u, v;
 	double  ur[2], vr[2];
@@ -56,9 +55,13 @@ char  *nm;
 		return;
 	}
 				/* set up sampling */
-	n = PI * il->sampdens;
-	nalt = sqrt(n/PI) + .5;
-	nazi = PI*nalt + .5;
+	if (il->sampdens <= 0)
+		nalt = nazi = 1;
+	else {
+		n = PI * il->sampdens;
+		nalt = sqrt(n/PI) + .5;
+		nazi = PI*nalt + .5;
+	}
 	n = nalt*nazi;
 	distarr = (float *)calloc(n, 3*sizeof(float));
 	if (distarr == NULL)
@@ -81,21 +84,18 @@ char  *nm;
 	    for (dim[2] = 0; dim[2] < nazi; dim[2]++)
 		for (i = 0; i < il->nsamps; i++) {
 					/* random direction */
-		    dim[3] = 1;
-		    r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
-		    dim[3] = 2;
-		    r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nazi;
+		    h = ilhash(dim, 3) + i;
+		    multisamp(sp, 2, urand(h));
+		    r1 = (dim[1] + sp[0])/nalt;
+		    r2 = (dim[2] + sp[1] - .5)/nazi;
 		    flatdir(dn, r1, r2);
 		    for (j = 0; j < 3; j++)
 			dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*fa->norm[j];
 					/* random location */
 		    do {
-			dim[3] = 3;
-			r1 = ur[0] + (ur[1]-ur[0]) *
-					urand(urind(ilhash(dim,4),i+nmisses));
-			dim[3] = 4;
-			r2 = vr[0] + (vr[1]-vr[0]) *
-					urand(urind(ilhash(dim,4),i+nmisses));
+			multisamp(sp, 2, urand(h+4862+nmisses));
+			r1 = ur[0] + (ur[1]-ur[0]) * sp[0];
+			r2 = vr[0] + (vr[1]-vr[0]) * sp[1];
 			for (j = 0; j < 3; j++)
 			    org[j] = r1*u[j] + r2*v[j]
 					+ fa->offset*fa->norm[j];
@@ -111,12 +111,16 @@ char  *nm;
 		    for (j = 0; j < 3; j++)
 			org[j] += .001*fa->norm[j];
 					/* send sample */
-		    raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
+		    raysamp(distarr+3*(dim[1]*nazi+dim[2]), org, dir, rt);
 		}
 	rayflush(rt);
-				/* write out the face w/ distribution */
-	flatout(il, distarr, nalt, nazi, u, v, fa->norm);
-	illumout(il, ob);
+				/* write out the face and its distribution */
+	if (average(il, distarr, nalt*nazi)) {
+		if (il->sampdens > 0)
+			flatout(il, distarr, nalt, nazi, u, v, fa->norm);
+		illumout(il, ob);
+	} else
+		printobj(il->altmat, ob);
 				/* clean up */
 	freeface(ob);
 	free((char *)distarr);
@@ -130,10 +134,10 @@ struct illum_args  *il;
 struct rtproc  *rt;
 char  *nm;
 {
-	int  dim[4];
+	int  dim[3];
 	int  n, nalt, nazi;
 	float  *distarr;
-	double  r1, r2, r3;
+	double  sp[4], r1, r2, r3;
 	FVECT  org, dir;
 	FVECT  u, v;
 	register int  i, j;
@@ -141,9 +145,13 @@ char  *nm;
 	if (ob->oargs.nfargs != 4)
 		objerror(ob, USER, "bad # of arguments");
 				/* set up sampling */
-	n = 4.*PI * il->sampdens;
-	nalt = sqrt(n/PI) + .5;
-	nazi = PI*nalt + .5;
+	if (il->sampdens <= 0)
+		nalt = nazi = 1;
+	else {
+		n = 4.*PI * il->sampdens;
+		nalt = sqrt(n/PI) + .5;
+		nazi = PI*nalt + .5;
+	}
 	n = nalt*nazi;
 	distarr = (float *)calloc(n, 3*sizeof(float));
 	if (distarr == NULL)
@@ -151,25 +159,18 @@ char  *nm;
 	dim[0] = random();
 				/* sample sphere */
 	for (dim[1] = 0; dim[1] < nalt; dim[1]++)
-	    for (dim[2] = 0; dim[2] < nazi; dim[2]++) {
-		if (il->nsamps > 2 && nazi > 20) {
-		    rounddir(dir, (dim[1]+.5)/nalt, (dim[2]+.5)/nazi);
-		    mkaxes(u, v, dir);
-		}
+	    for (dim[2] = 0; dim[2] < nazi; dim[2]++)
 		for (i = 0; i < il->nsamps; i++) {
+					/* next sample point */
+		    multisamp(sp, 4, urand(ilhash(dim,3)+i));
 					/* random direction */
-		    dim[3] = 1;
-		    r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
-		    dim[3] = 2;
-		    r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nazi;
+		    r1 = (dim[1] + sp[0])/nalt;
+		    r2 = (dim[2] + sp[1] - .5)/nazi;
 		    rounddir(dir, r1, r2);
 					/* random location */
-		    if (il->nsamps <= 2 || nazi <= 20)
-			mkaxes(u, v, dir);		/* yuck! */
-		    dim[3] = 3;
-		    r3 = sqrt(urand(urind(ilhash(dim,4),i)));
-		    dim[3] = 4;
-		    r2 = 2.*PI*urand(urind(ilhash(dim,4),i));
+		    mkaxes(u, v, dir);		/* yuck! */
+		    r3 = sqrt(sp[2]);
+		    r2 = 2.*PI*sp[3];
 		    r1 = r3*ob->oargs.farg[3]*cos(r2);
 		    r2 = r3*ob->oargs.farg[3]*sin(r2);
 		    r3 = ob->oargs.farg[3]*sqrt(1.01-r3*r3);
@@ -179,13 +180,18 @@ char  *nm;
 			dir[j] = -dir[j];
 		    }
 					/* send sample */
-		    raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
+		    raysamp(distarr+3*(dim[1]*nazi+dim[2]), org, dir, rt);
 		}
-	    }
 	rayflush(rt);
-				/* write out the sphere w/ distribution */
-	roundout(il, distarr, nalt, nazi);
-	illumout(il, ob);
+				/* write out the sphere and its distribution */
+	if (average(il, distarr, nalt*nazi)) {
+		if (il->sampdens > 0)
+			roundout(il, distarr, nalt, nazi);
+		else
+			objerror(ob, WARNING, "diffuse distribution");
+		illumout(il, ob);
+	} else
+		printobj(il->altmat, ob);
 				/* clean up */
 	free((char *)distarr);
 }
@@ -197,10 +203,10 @@ struct illum_args  *il;
 struct rtproc  *rt;
 char  *nm;
 {
-	int  dim[4];
+	int  dim[3];
 	int  n, nalt, nazi;
 	float  *distarr;
-	double  r1, r2, r3;
+	double  sp[4], r1, r2, r3;
 	FVECT  dn, org, dir;
 	FVECT  u, v;
 	register CONE  *co;
@@ -208,9 +214,13 @@ char  *nm;
 				/* get/check arguments */
 	co = getcone(ob, 0);
 				/* set up sampling */
-	n = PI * il->sampdens;
-	nalt = sqrt(n/PI) + .5;
-	nazi = PI*nalt + .5;
+	if (il->sampdens <= 0)
+		nalt = nazi = 1;
+	else {
+		n = PI * il->sampdens;
+		nalt = sqrt(n/PI) + .5;
+		nazi = PI*nalt + .5;
+	}
 	n = nalt*nazi;
 	distarr = (float *)calloc(n, 3*sizeof(float));
 	if (distarr == NULL)
@@ -221,21 +231,18 @@ char  *nm;
 	for (dim[1] = 0; dim[1] < nalt; dim[1]++)
 	    for (dim[2] = 0; dim[2] < nazi; dim[2]++)
 		for (i = 0; i < il->nsamps; i++) {
+					/* next sample point */
+		    multisamp(sp, 4, urand(ilhash(dim,3)+i));
 					/* random direction */
-		    dim[3] = 1;
-		    r1 = (dim[1]+urand(urind(ilhash(dim,4),i)))/nalt;
-		    dim[3] = 2;
-		    r2 = (dim[2]+urand(urind(ilhash(dim,4),i)))/nalt;
+		    r1 = (dim[1] + sp[0])/nalt;
+		    r2 = (dim[2] + sp[1] - .5)/nazi;
 		    flatdir(dn, r1, r2);
 		    for (j = 0; j < 3; j++)
 			dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j];
 					/* random location */
-		    dim[3] = 3;
 		    r3 = sqrt(CO_R0(co)*CO_R0(co) +
-				urand(urind(ilhash(dim,4),i))*
-				(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
-		    dim[3] = 4;
-		    r2 = 2.*PI*urand(urind(ilhash(dim,4),i));
+			    sp[2]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
+		    r2 = 2.*PI*sp[3];
 		    r1 = r3*cos(r2);
 		    r2 = r3*sin(r2);
 		    for (j = 0; j < 3; j++)
@@ -243,12 +250,16 @@ char  *nm;
 					.001*co->ad[j];
 
 					/* send sample */
-		    raysamp(distarr+dim[1]*nazi+dim[2], org, dir, rt);
+		    raysamp(distarr+3*(dim[1]*nazi+dim[2]), org, dir, rt);
 		}
 	rayflush(rt);
-				/* write out the ring w/ distribution */
-	flatout(il, distarr, nalt, nazi, u, v, co->ad);
-	illumout(il, ob);
+				/* write out the ring and its distribution */
+	if (average(il, distarr, nalt*nazi)) {
+		if (il->sampdens > 0)
+			flatout(il, distarr, nalt, nazi, u, v, co->ad);
+		illumout(il, ob);
+	} else
+		printobj(il->altmat, ob);
 				/* clean up */
 	freecone(ob);
 	free((char *)distarr);
@@ -278,8 +289,8 @@ register struct rtproc  *rt;
 
 	if (rt->nrays <= 0)
 		return;
-	i = 6*rt->nrays + 3;
-	rt->buf[i++] = 0.; rt->buf[i++] = 0.; rt->buf[i] = 0.;
+	bzero(rt->buf+6*rt->nrays, 6*sizeof(float));
+	errno = 0;
 	if ( process(rt->pd, (char *)rt->buf, (char *)rt->buf,
 			3*sizeof(float)*rt->nrays,
 			6*sizeof(float)*(rt->nrays+1)) <