--- ray/src/common/face.c	1996/03/22 09:01:16	2.5
+++ ray/src/common/face.c	2003/03/12 17:26:58	2.8
@@ -1,15 +1,12 @@
-/* Copyright (c) 1995 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char RCSid[] = "$Id: face.c,v 2.8 2003/03/12 17:26:58 greg Exp $";
 #endif
-
 /*
  *  face.c - routines dealing with polygonal faces.
- *
- *     8/30/85
  */
 
+#include "copyright.h"
+
 #include  "standard.h"
 
 #include  "object.h"
@@ -104,6 +101,7 @@ OBJREC  *o;
 }
 
 
+void
 freeface(o)			/* free memory associated with face */
 OBJREC  *o;
 {
@@ -114,12 +112,14 @@ OBJREC  *o;
 }
 
 
+int
 inface(p, f)			/* determine if point is in face */
 FVECT  p;
 FACE  *f;
 {
 	int  ncross, n;
 	double  x, y;
+	int  tst;
 	register int  xi, yi;
 	register FLOAT  *p0, *p1;
 
@@ -133,13 +133,15 @@ FACE  *f;
 	ncross = 0;
 					/* positive x axis cross test */
 	while (n--) {
-		if ((p0[yi] > y) ^ (p1[yi] > y))
-			if (p0[xi] > x && p1[xi] > x)
+		if ((p0[yi] > y) ^ (p1[yi] > y)) {
+			tst = (p0[xi] > x) + (p1[xi] > x);
+			if (tst == 2)
 				ncross++;
-			else if (p0[xi] > x || p1[xi] > x)
+			else if (tst)
 				ncross += (p1[yi] > p0[yi]) ^
 						((p0[yi]-y)*(p1[xi]-x) >
 						(p0[xi]-x)*(p1[yi]-y));
+		}
 		p0 = p1;
 		p1 += 3;
 	}