text: # math3d_line.py
  
  class Line(object):
      def __init__(self, center, unit_normal):
          self.center = center.clone()
          self.unit_normal = unit_normal.clone()
  
      def clone(self):
          return Line(self.center, self.unit_normal)
  
      def contains_point(self, point, eps=1e-7):
          return (point - self.center).rejected(self.unit_normal).length() < eps