--- ray/src/ot/o_cone.c	1989/02/02 10:33:02	1.1
+++ ray/src/ot/o_cone.c	2016/04/21 00:40:35	2.7
@@ -1,9 +1,6 @@
-/* Copyright (c) 1986 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: o_cone.c,v 2.7 2016/04/21 00:40:35 greg Exp $";
 #endif
-
 /*
  *  o_cone.c - routines for intersecting cubes with cones.
  *
@@ -11,13 +8,15 @@ static char SCCSid[] = "$SunId$ LBL";
  */
 
 #include  "standard.h"
-
 #include  "octree.h"
-
 #include  "object.h"
-
 #include  "cone.h"
+#include  "plocate.h"
 
+#ifndef STRICT
+#define STRICT	1
+#endif
+
 #define  ROOT3		1.732050808
 
 /*
@@ -35,43 +34,52 @@ static char SCCSid[] = "$SunId$ LBL";
 
 extern double  mincusize;		/* minimum cube size */
 
+static int findcseg(FVECT ep0, FVECT ep1, CONE *co, FVECT p);
 
-o_cone(o, cu)			/* determine if cone intersects cube */
-OBJREC  *o;
-register CUBE  *cu;
+
+
+extern int
+o_cone(		/* determine if cone intersects cube */
+	OBJREC  *o,
+	CUBE  *cu
+)
 {
-	double  dist2lseg(), findcseg();
 	CONE  *co;
 	FVECT  ep0, ep1;
+#if STRICT
 	FVECT  cumin, cumax;
 	CUBE  cukid;
+	int  j;
+#endif
 	double  r;
 	FVECT  p;
-	register int  i, j;
+	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(0);
-#ifdef  STRICT
+			return(O_MISS);
+#if  STRICT
 					/* get cube boundaries */
 		for (i = 0; i < 3; i++)
 			cumax[i] = (cumin[i] = cu->cuorg[i]) + cu->cusize;
 					/* closest segment intersects? */
 		if (clip(ep0, ep1, cumin, cumax))
-			return(1);
+			return(O_HIT);
 	}
 					/* check sub-cubes */
 	cukid.cusize = cu->cusize * 0.5;
 	if (cukid.cusize < mincusize)
-		return(1);		/* cube too small */
+		return(O_HIT);		/* cube too small */
 	cukid.cutree = EMPTY;
 
 	for (j = 0; j < 8; j++) {
@@ -81,36 +89,38 @@ register CUBE  *cu;
 				cukid.cuorg[i] += cukid.cusize;
 		}
 		if (o_cone(o, &cukid))
-			return(1);	/* sub-cube intersects */
+			return(O_HIT);	/* sub-cube intersects */
 	}
-	return(0);			/* no intersection */
+	return(O_MISS);			/* no intersection */
 #else
 	}
-	return(1);			/* assume intersection */
+	return(O_HIT);			/* assume intersection */
 #endif
 }
 
 
-double
-findcseg(ep0, ep1, co, p)	/* find line segment from cone closest to p */
-FVECT  ep0, ep1;
-register CONE  *co;
-FVECT  p;
+static int
+findcseg(	/* find line segment from cone closest to p */
+	FVECT  ep0,
+	FVECT  ep1,
+	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 */
 }