#ifndef D3SPHERE_H
#define D3SPHERE_H

#include <point.h>

class d3sphere : public d3func
{
public:

  point3<double> center;

  double radius;

  d3sphere( point3<double> const & _center, double const _radius )
    : center(_center), radius(_radius) {}
  
  virtual double const eval(point3<double> const & X) const
  {
    point3<double> Y(X);
    Y -= center;
    return radius*radius - Y.dot();
  }
};

#endif