--- ray/src/cv/obj2rad.c	1994/06/22 12:35:59	2.15
+++ ray/src/cv/obj2rad.c	2003/03/04 01:42:29	2.18
@@ -1,9 +1,6 @@
-/* Copyright (c) 1994 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: obj2rad.c,v 2.18 2003/03/04 01:42:29 greg Exp $";
 #endif
-
 /*
  * Convert a Wavefront .obj file to Radiance format.
  *
@@ -560,6 +557,7 @@ char	*v1, *v2, *v3;
 	BARYCCM	bvecs;
 	FLOAT	bcoor[3][3];
 	int	texOK, patOK;
+	int	flatness;
 	register int	i;
 
 	if ((mod = getmtl()) == NULL)
@@ -568,7 +566,26 @@ char	*v1, *v2, *v3;
 	if (!cvtndx(v1i, v1) || !cvtndx(v2i, v2) || !cvtndx(v3i, v3))
 		return(0);
 					/* compute barycentric coordinates */
-	texOK = !flatten && (v1i[2]>=0 && v2i[2]>=0 && v3i[2]>=0);
+	if (v1i[2]>=0 && v2i[2]>=0 && v3i[2]>=0)
+		flatness = flat_tri(vlist[v1i[0]], vlist[v2i[0]], vlist[v3i[0]],
+				vnlist[v1i[2]], vnlist[v2i[2]], vnlist[v3i[2]]);
+	else
+		flatness = ISFLAT;
+
+	switch (flatness) {
+	case DEGEN:			/* zero area */
+		return(-1);
+	case RVFLAT:			/* reversed normals, but flat */
+	case ISFLAT:			/* smoothing unnecessary */
+		texOK = 0;
+		break;
+	case RVBENT:			/* reversed normals with smoothing */
+	case ISBENT:			/* proper smoothing */
+		texOK = 1;
+		break;
+	}
+	if (flatten)
+		texOK = 0;
 #ifdef TEXMAPS
 	patOK = mapname[0] && (v1i[1]>=0 && v2i[1]>=0 && v3i[1]>=0);
 #else
@@ -606,13 +623,18 @@ char	*v1, *v2, *v3;
 		put_baryc(&bvecs, bcoor, 2);
 	}
 #endif
-					/* put out triangle */
+					/* put out (reversed) triangle */
 	printf("\n%s polygon %s.%d\n", mod, getonm(), faceno);
 	printf("0\n0\n9\n");
-	pvect(vlist[v1i[0]]);
-	pvect(vlist[v2i[0]]);
-	pvect(vlist[v3i[0]]);
-
+	if (flatness == RVFLAT || flatness == RVBENT) {
+		pvect(vlist[v3i[0]]);
+		pvect(vlist[v2i[0]]);
+		pvect(vlist[v1i[0]]);
+	} else {
+		pvect(vlist[v1i[0]]);
+		pvect(vlist[v2i[0]]);
+		pvect(vlist[v3i[0]]);
+	}
 	return(1);
 }
 
@@ -620,15 +642,15 @@ char	*v1, *v2, *v3;
 freeverts()			/* free all vertices */
 {
 	if (nvs) {
-		free((char *)vlist);
+		free((void *)vlist);
 		nvs = 0;
 	}
 	if (nvts) {
-		free((char *)vtlist);
+		free((void *)vtlist);
 		nvts = 0;
 	}
 	if (nvns) {
-		free((char *)vnlist);
+		free((void *)vnlist);
 		nvns = 0;
 	}
 }