def main():
pygame.init()
passing_thrus=((240,300),(230,50),(340,218),(348,487), \
(150,200),(278,245),(453,385),(140,238),(240,300))
screen=pygame.display.set_mode((500,500),0,24)
bg=pygame.surface.Surface((500,500),0,24)
clock=pygame.time.Clock()
i=Curve("catmull")
k=Curve("catmull")
i.set_passthru(passing_thrus)
k.set_passthru(passing_thrus)
#Set Curve 'k' to be a closed curve
k.set_closed(True)
steps=2
steps1=2
points=i.yieldall(60)
points1=k.yieldall(60)
#c1,c2=i.get_control()[0],i.get_control()[1]
print "control",i.get_control()
print "No. of points obtained",len(points)
while 1:
clock.tick(60)
steps+=1
if steps==len(points):
steps=2
bg.fill((255,255,255))
pygame.draw.aalines(bg,(255,0,0),0,list(points[i] for i in range(steps)))
pygame.draw.aalines(bg,(0,255,0),0,list(points1[i] for i in range(steps)))
pygame.draw.aalines(bg,(255,0,0),0,((0,500),points[steps]))
pygame.draw.aalines(bg,(0,255,0),0,((500,0),points1[steps]))
for point in passing_thrus:
pygame.draw.rect(bg,(255,0,0),Rect(point[0],point[1],5,5))
screen.blit(bg,(0,0))
pygame.display.update()
