--- ray/src/ot/sphere.c	1989/10/14 11:19:36	1.2
+++ ray/src/ot/sphere.c	2003/02/22 02:07:26	2.2
@@ -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: sphere.c,v 2.2 2003/02/22 02:07:26 greg Exp $";
 #endif
-
 /*
  *  sphere.c - routines for creating octrees for spheres.
  *
@@ -59,14 +56,21 @@ register CUBE  *cu;
 {
 	FVECT  v1;
 	double  d1, d2;
-	register double  *fa;
+	register FLOAT  *fa;
 	register int  i;
 #define  cent		fa
 #define  rad		fa[3]
 					/* get arguments */
+	if (o->oargs.nfargs != 4)
+		objerror(o, USER, "bad # arguments");
 	fa = o->oargs.farg;
-	if (o->oargs.nfargs != 4 || rad <= FTINY)
-		objerror(o, USER, "bad arguments");
+	if (rad < -FTINY) {
+		objerror(o, WARNING, "negative radius");
+		o->otype = o->otype == OBJ_SPHERE ?
+				OBJ_BUBBLE : OBJ_SPHERE;
+		rad = -rad;
+	} else if (rad <= FTINY)
+		objerror(o, USER, "zero radius");
 
 	d1 = ROOT3/2.0 * cu->cusize;	/* bounding radius for cube */