--- ray/src/rt/sphere.c	2003/03/12 04:59:05	2.5
+++ ray/src/rt/sphere.c	2021/01/31 18:08:04	2.9
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: sphere.c,v 2.5 2003/03/12 04:59:05 greg Exp $";
+static const char RCSid[] = "$Id: sphere.c,v 2.9 2021/01/31 18:08:04 greg Exp $";
 #endif
 /*
  *  sphere.c - compute ray intersection with spheres.
@@ -8,20 +8,22 @@ static const char RCSid[] = "$Id: sphere.c,v 2.5 2003/
 #include "copyright.h"
 
 #include  "ray.h"
-
 #include  "otypes.h"
+#include  "rtotypes.h"
 
 
-o_sphere(so, r)			/* compute intersection with sphere */
-OBJREC  *so;
-register RAY  *r;
+int
+o_sphere(			/* compute intersection with sphere */
+	OBJREC  *so,
+	RAY  *r
+)
 {
 	double  a, b, c;	/* coefficients for quadratic equation */
 	double  root[2];	/* quadratic roots */
 	int  nroots;
 	double  t;
-	register FLOAT  *ap;
-	register int  i;
+	RREAL  *ap;
+	int  i;
 
 	if (so->oargs.nfargs != 4)
 		objerror(so, USER, "bad # arguments");
@@ -61,9 +63,8 @@ register RAY  *r;
 			break;
 	if (i >= nroots)
 		return(0);			/* no positive root */
-
-	if (t >= r->rot)
-		return(0);			/* other is closer */
+	if (rayreject(so, r, t))
+		return(0);			/* previous hit better */
 
 	r->ro = so;
 	r->rot = t;