--- ray/src/ot/o_cone.c	2004/03/27 12:41:45	2.3
+++ ray/src/ot/o_cone.c	2016/04/21 00:40:35	2.7
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: o_cone.c,v 2.3 2004/03/27 12:41:45 schorsch Exp $";
+static const char	RCSid[] = "$Id: o_cone.c,v 2.7 2016/04/21 00:40:35 greg Exp $";
 #endif
 /*
  *  o_cone.c - routines for intersecting cubes with cones.
@@ -11,7 +11,12 @@ static const char	RCSid[] = "$Id: o_cone.c,v 2.3 2004/
 #include  "octree.h"
 #include  "object.h"
 #include  "cone.h"
+#include  "plocate.h"
 
+#ifndef STRICT
+#define STRICT	1
+#endif
+
 #define  ROOT3		1.732050808
 
 /*
@@ -29,40 +34,41 @@ static const char	RCSid[] = "$Id: o_cone.c,v 2.3 2004/
 
 extern double  mincusize;		/* minimum cube size */
 
-static double findcseg(FVECT ep0, FVECT ep1, CONE *co, FVECT p);
+static int findcseg(FVECT ep0, FVECT ep1, CONE *co, FVECT p);
 
 
 
-/* XXX o_cone() is extern, but not declared in any header file */
-int
-o_cone(			/* determine if cone intersects cube */
+extern int
+o_cone(		/* determine if cone intersects cube */
 	OBJREC  *o,
-	register CUBE  *cu
+	CUBE  *cu
 )
 {
 	CONE  *co;
 	FVECT  ep0, ep1;
-#ifdef STRICT
+#if STRICT
 	FVECT  cumin, cumax;
 	CUBE  cukid;
-	register int  j;
+	int  j;
 #endif
 	double  r;
 	FVECT  p;
-	register int  i;
+	int  i;
 					/* get cone arguments */
 	co = getcone(o, 0);
+	if (co == NULL)			/* check for degenerate case */
+		return(O_MISS);
 					/* get cube center */
 	r = cu->cusize * 0.5;
 	for (i = 0; i < 3; i++)
 		p[i] = cu->cuorg[i] + r;
 	r *= ROOT3;			/* bounding radius for cube */
 
-	if (findcseg(ep0, ep1, co, p) > 0.0) {
+	if (findcseg(ep0, ep1, co, p)) {
 					/* check min. distance to cone */
 		if (dist2lseg(p, ep0, ep1) > (r+FTINY)*(r+FTINY))
 			return(O_MISS);
-#ifdef  STRICT
+#if  STRICT
 					/* get cube boundaries */
 		for (i = 0; i < 3; i++)
 			cumax[i] = (cumin[i] = cu->cuorg[i]) + cu->cusize;
@@ -93,28 +99,28 @@ o_cone(			/* determine if cone intersects cube */
 }
 
 
-static double
+static int
 findcseg(	/* find line segment from cone closest to p */
 	FVECT  ep0,
 	FVECT  ep1,
-	register CONE  *co,
+	CONE  *co,
 	FVECT  p
 )
 {
 	double  d;
 	FVECT  v;
-	register int  i;
+	int  i;
 					/* find direction from axis to point */
-	for (i = 0; i < 3; i++)
-		v[i] = p[i] - CO_P0(co)[i];
+	VSUB(v, p, CO_P0(co));
 	d = DOT(v, co->ad);
 	for (i = 0; i < 3; i++)
-		v[i] = v[i] - d*co->ad[i];
-	d = normalize(v);
-	if (d > 0.0)			/* find endpoints of segment */
-		for (i = 0; i < 3; i++) {
-			ep0[i] = CO_R0(co)*v[i] + CO_P0(co)[i];
-			ep1[i] = CO_R1(co)*v[i] + CO_P1(co)[i];
-		}
-	return(d);			/* return distance from axis */
+		v[i] -= d*co->ad[i];
+	if (normalize(v) == 0.0)
+		return(0);
+					/* find endpoints of segment */
+	for (i = 0; i < 3; i++) {
+		ep0[i] = CO_R0(co)*v[i] + CO_P0(co)[i];
+		ep1[i] = CO_R1(co)*v[i] + CO_P1(co)[i];
+	}
+	return(1);			/* return distance from axis */
 }