--- ray/src/rt/m_mirror.c	1991/11/12 17:10:20	2.1
+++ ray/src/rt/m_mirror.c	1995/07/26 16:53:25	2.4
@@ -43,15 +43,18 @@ register RAY  *r;
 					/* check for substitute material */
 	if (m->oargs.nsargs > 0 &&
 			(r->rsrc < 0 || source[r->rsrc].so != r->ro)) {
-		rayshade(r, modifier(m->oargs.sarg[0]));
-		return;
+		if (!strcmp(m->oargs.sarg[0], VOIDID)) {
+			raytrans(r);
+			return(1);
+		}
+		return(rayshade(r, modifier(m->oargs.sarg[0])));
 	}
 					/* check for bad source ray */
 	if (r->rsrc >= 0 && source[r->rsrc].so != r->ro)
-		return;
+		return(1);
 
 	if (r->rod < 0.)		/* back is black */
-		return;
+		return(1);
 					/* get modifiers */
 	raytexture(r, m->omod);
 					/* assign material color */
@@ -72,14 +75,19 @@ register RAY  *r;
 		double  pdot;
 
 		if (rayorigin(&nr, r, REFLECTED, bright(mcolor)) < 0)
-			return;
+			return(1);
 		pdot = raynormal(pnorm, r);	/* use textures */
 		for (i = 0; i < 3; i++)
 			nr.rdir[i] = r->rdir[i] + 2.*pdot*pnorm[i];
+						/* check for penetration */
+		if (DOT(nr.rdir, r->ron) <= FTINY)
+			for (i = 0; i < 3; i++)
+				nr.rdir[i] = r->rdir[i] + 2.*r->rod*r->ron[i];
 	}
 	rayvalue(&nr);
 	multcolor(nr.rcol, mcolor);
 	addcolor(r->rcol, nr.rcol);
+	return(1);
 }