#! /usr/bin/python3

import pygame
from time import sleep
from math import sin

WIDTH = 1000
HEIGHT = 700

def main():
    pygame.init()
    points = {(i, -10) for i in range(HEIGHT)}
    screen = pygame.display.set_mode((WIDTH, HEIGHT))
    surface = pygame.Surface((WIDTH, HEIGHT))
    phase = 0
    while True:
        phase += 0.1
        points = {(i, v+sin(phase+0.01*phase*i)) for (i, v) in points}
        for i, v in points:
            screen.set_at((int(v*30+WIDTH/2), i), 16777215)
        pygame.display.flip()
        sleep(0.01)
        screen.fill(0)


if __name__ == '__main__':
    main()