code: def from_polar(self, r, theta, h):
          
          center = self.size() / 2.0
          r = r * center['x']
  
          return center + Vector(r * math.cos(theta),
                                 r * math.sin(theta),
                                 center['z'] * h)
docs: Converts polar coordiantes within a placeable into a :Vector:
  
          The origin is assumed to be in the center of a Placeable
  
          :r: is between -1.0 and 1.0, relative to max X
          :h: is between -1.0 and 1.0, relative to max Z