func RectFromSphere(c Vec3, r float32) Rectangle {
	return RectWHD(c[0]-r, c[1]-r, c[2]-r, 2*r, 2*r, 2*r)
}
func RectFromSphere(c Vec3, r float32) Rectangle {
	return RectWHD(c[0]-r, c[1]-r, c[2]-r, 2*r, 2*r, 2*r)
}
func RectFromSphere ( c Vec3 , r float32 ) Rectangle { return RectWHD ( c [ 0 ] - r , c [ 1 ] - r , c [ 2 ] - r , 2 * r , 2 * r , 2 * r ) }
// RectFromSphere returns the minimum rectangle that contains the circle of
// center c and radius r.
RectFromSphere returns the minimum rectangle that contains the circle of center c and radius r .