--- ray/src/gen/mkillum2.c	1991/08/22 12:12:23	1.11
+++ ray/src/gen/mkillum2.c	1991/11/08 13:17:47	1.14
@@ -88,7 +88,7 @@ char  *nm;
 		    h = ilhash(dim, 3) + i;
 		    multisamp(sp, 2, urand(h));
 		    r1 = (dim[1] + sp[0])/nalt;
-		    r2 = (dim[2] + sp[1])/nazi;
+		    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];
@@ -116,10 +116,12 @@ char  *nm;
 		}
 	rayflush(rt);
 				/* write out the face and its distribution */
-	average(il, distarr, nalt*nazi);
-	if (il->sampdens > 0)
-		flatout(il, distarr, nalt, nazi, u, v, fa->norm);
-	illumout(il, ob);
+	if (average(il, distarr, nalt*nazi)) {
+		if (il->sampdens > 0)
+			flatout(il, distarr, nalt, nazi, u, v, fa->norm);
+		illumout(il, ob);
+	} else if (!(il->flags & IL_LIGHT))
+		printobj(il->altmat, ob);
 				/* clean up */
 	freeface(ob);
 	free((char *)distarr);
@@ -164,7 +166,7 @@ char  *nm;
 		    multisamp(sp, 4, urand(ilhash(dim,3)+i));
 					/* random direction */
 		    r1 = (dim[1] + sp[0])/nalt;
-		    r2 = (dim[2] + sp[1])/nazi;
+		    r2 = (dim[2] + sp[1] - .5)/nazi;
 		    rounddir(dir, r1, r2);
 					/* random location */
 		    mkaxes(u, v, dir);		/* yuck! */
@@ -183,12 +185,14 @@ char  *nm;
 		}
 	rayflush(rt);
 				/* write out the sphere and its distribution */
-	average(il, distarr, nalt*nazi);
-	if (il->sampdens > 0)
-		roundout(il, distarr, nalt, nazi);
-	else
-		objerror(ob, WARNING, "diffuse distribution");
-	illumout(il, ob);
+	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 if (!(il->flags & IL_LIGHT))
+		printobj(il->altmat, ob);
 				/* clean up */
 	free((char *)distarr);
 }
@@ -232,7 +236,7 @@ char  *nm;
 		    multisamp(sp, 4, urand(ilhash(dim,3)+i));
 					/* random direction */
 		    r1 = (dim[1] + sp[0])/nalt;
-		    r2 = (dim[2] + sp[1])/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];
@@ -251,10 +255,12 @@ char  *nm;
 		}
 	rayflush(rt);
 				/* write out the ring and its distribution */
-	average(il, distarr, nalt*nazi);
-	if (il->sampdens > 0)
-		flatout(il, distarr, nalt, nazi, u, v, co->ad);
-	illumout(il, ob);
+	if (average(il, distarr, nalt*nazi)) {
+		if (il->sampdens > 0)
+			flatout(il, distarr, nalt, nazi, u, v, co->ad);
+		illumout(il, ob);
+	} else if (!(il->flags & IL_LIGHT))
+		printobj(il->altmat, ob);
 				/* clean up */
 	freecone(ob);
 	free((char *)distarr);
@@ -285,6 +291,7 @@ register struct rtproc  *rt;
 	if (rt->nrays <= 0)
 		return;
 	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)) <