sphere.py

import vector3
from util import format_number

class Sphere(object):
    
    def __init__(self, position=(0,0,0), radius= 1.):
        
        self._position = vector3.Vector3(position)
        self._radius = float(radius)
        
        
    def get_position(self):
        return self._position
    def set_position(self, position):
        self._position.set(*position)
    position = property(get_position, set_position, None, "Position of sphere centre.")
    
    def get_radius(self):
        return self._radius
    def set_radius(self, radius):
        self._radius = float(radius)
    radius = property(get_radius, set_radius, None, "Radius of the sphere.")
        
        
    def __str__(self):
        
        return "( position %s, radius %s )" % (self.position, format_number(self.radius))
    
    
    def __repr__(self):
        
        return "Sphere(%s, %s)" % (tuple(self.position), self.radius)
        
        
    def __contains__(self, shape):
        
        try:
            return shape.in_sphere(self)
        except AttributeError:
            raise TypeError( "No 'in_sphere' method supplied by %s" % type(shape) )
            
            
    def contains(self, shape):
        
        return shape in self
            
            
    def in_sphere(self, sphere):
        
        return self.position.get_distance(sphere.position) + self.radius <= sphere.radius
        
        
    def intersects(self, shape):
        
        try:
            return shape.intersects_sphere(self)
        except AttributeError:
            raise TypeError( "No 'intersects_sphere' method supplied by %s" % type(shape) )
    
    
    def intersects_sphere(self, sphere):
        
        return self.position.get_distance(sphere.position) < self.radius + sphere.radius

        
if __name__ == "__main__":
    
    s1 = Sphere()
    s2 = Sphere( (1,1,1) )
    s3 = Sphere( radius=10 )
    s4 = eval(repr(s2))
    
    print s1
    print repr(s2)
    print s2, s4
    
    v = vector3.Vector3(0, 1, 0)
    print v in s1
    
    big = Sphere(radius=1)
    small = Sphere(position=(.8, 0, 0), radius=.2)
     
    
    print small, big
    print small in big