import pygame
from pygame.locals import *
import numpy
import sys

import os
import platform
 
if platform.system() == 'Windows':
    os.environ['SDL_VIDEODRIVER'] = 'windib'

    
pygame.init()

screen = pygame.display.set_mode((640,480))

class Bullet:
    def __init__(self, pos=(0,0), vel=(0,0)):
        x,y = pos
        self.position = numpy.array([float(x),float(y)])
        x,y = vel
        self.velocity = numpy.array([float(x),float(y)])

    def update(self):
        self.position += self.velocity
        # collide here

    def draw(self):
        pygame.draw.circle(screen,(255,0,0),
                           (int(self.position[0]), int(self.position[1])), 3 )

if __name__ == "__main__":

    bullets = []
    pos = (0, 0)
    for i in xrange ( 10 ):
        bullets.append ( Bullet ( pos, (i*0.25, 0.5) ) )

    clock = pygame.time.Clock()

    while True:
        for event in pygame.event.get():
            if event.type == QUIT or (event.type==KEYDOWN and event.key==K_ESCAPE):
                pygame.quit()
                sys.exit()

        clock.tick(30)

        for bullet in bullets:
            bullet.update()

        screen.fill( (0,0,0) )
        for bullet in bullets:
            bullet.draw()
        pygame.display.update()