--- ray/src/rt/m_mirror.c	1992/11/20 12:09:16	2.2
+++ ray/src/rt/m_mirror.c	2003/02/25 02:47:22	2.9
@@ -1,13 +1,12 @@
-/* Copyright (c) 1991 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: m_mirror.c,v 2.9 2003/02/25 02:47:22 greg Exp $";
 #endif
-
 /*
  * Routines for mirror material supporting virtual light sources
  */
 
+#include "copyright.h"
+
 #include  "ray.h"
 
 #include  "otypes.h"
@@ -26,16 +25,19 @@ static char SCCSid[] = "$SunId$ LBL";
  */
 
 
-int  mir_proj();
+static int  mir_proj(), mirrorproj();
+
 VSMATERIAL  mirror_vs = {mir_proj, 1};
 
 
+int
 m_mirror(m, r)			/* shade mirrored ray */
 register OBJREC  *m;
 register RAY  *r;
 {
 	COLOR  mcolor;
 	RAY  nr;
+	int  rpure = 1;
 	register int  i;
 					/* check arguments */
 	if (m->oargs.nfargs != 3 || m->oargs.nsargs > 1)
@@ -43,15 +45,18 @@ 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, lastmod(objndx(m), 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 */
@@ -72,33 +77,49 @@ register RAY  *r;
 		double  pdot;
 
 		if (rayorigin(&nr, r, REFLECTED, bright(mcolor)) < 0)
-			return;
-		pdot = raynormal(pnorm, r);	/* use textures */
-		for (i = 0; i < 3; i++)
-			nr.rdir[i] = r->rdir[i] + 2.*pdot*pnorm[i];
+			return(1);
+		if (DOT(r->pert,r->pert) > FTINY*FTINY) {
+			pdot = raynormal(pnorm, r);	/* use textures */
+			for (i = 0; i < 3; i++)
+				nr.rdir[i] = r->rdir[i] + 2.*pdot*pnorm[i];
+			rpure = 0;
+		}
 						/* check for penetration */
-		if (DOT(nr.rdir, r->ron) <= FTINY)
+		if (rpure || 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);
+	if (rpure && r->ro != NULL && isflat(r->ro->otype))
+		r->rt = r->rot + nr.rt;
+	return(1);
 }
 
 
+static int
 mir_proj(pm, o, s, n)		/* compute a mirror's projection */
 MAT4  pm;
 register OBJREC  *o;
 SRCREC  *s;
 int  n;
 {
-	FVECT  nv;
+	FVECT  nv, sc;
 	double  od;
+	register int  i, j;
 				/* get surface normal and offset */
 	od = getplaneq(nv, o);
-				/* check for behind */
-	if (DOT(s->sloc, nv) <= (s->sflags & SDISTANT ? FTINY : od+FTINY))
+				/* check for extreme point for behind */
+	VCOPY(sc, s->sloc);
+	for (i = s->sflags & SFLAT ? SV : SW; i >= 0; i--)
+		if (DOT(nv, s->ss[i]) > 0.)
+			for (j = 0; j < 3; j++)
+				sc[j] += s->ss[i][j];
+		else
+			for (j = 0; j < 3; j++)
+				sc[j] -= s->ss[i][j];
+	if (DOT(sc, nv) <= (s->sflags & SDISTANT ? FTINY : od+FTINY))
 		return(0);
 				/* everything OK -- compute projection */
 	mirrorproj(pm, nv, od);
@@ -106,6 +127,7 @@ int  n;
 }
 
 
+static int
 mirrorproj(m, nv, offs)		/* get mirror projection for surface */
 register MAT4  m;
 FVECT  nv;