import pippy, pygame, sys
from pygame.locals import *
from random import *
import math

# always need to init first thing
pygame.init()

# XO screen is 1200x900
size = width, height = 1200, 900

# create the window and keep track of the surface
# for drawing into
screen = pygame.display.set_mode(size)

# turn off the cursor
pygame.mouse.set_visible(False)

color = (250,250,250)
min_factor = 0.8
max_factor = 0.9
start_length = 130
min_length = 40
min_angle_delta = 0.4
max_angle_delta = 0.5

# start the screen all black
bgcolor = (0,0,0)
screen.fill(bgcolor)

def draw_tree(x, y, length, angle):
  x2 = x + length * math.sin(angle)
  y2 = y - length * math.cos(angle)
  pygame.draw.line(screen, color, (x, y), (x2, y2))

  if length > min_length:
    # draw left branch
    left_angle = angle - \\
      uniform(min_angle_delta, max_angle_delta)
    left_length = length * \\
      uniform(min_factor, max_factor)
    draw_tree(x2, y2, left_length, left_angle)
    # draw middle branch
    middle_length = length * \\
      uniform(min_factor, max_factor)
    draw_tree(x2, y2, middle_length, angle)
    # draw right branch
    right_angle = angle + \\
      uniform(min_angle_delta, max_angle_delta)
    right_length = length * \\
      uniform(min_factor, max_factor)
    draw_tree(x2, y2, right_length, right_angle)

# clear the screen
screen.fill(bgcolor)

# draw a tree, starting at the bottom centre of the
# screen
draw_tree((width / 2), height - 20, start_length, 0)
pygame.display.flip()

while pippy.pygame.next_frame():
  # chill until a key is pressed
  for event in pygame.event.get():
    if event.type == QUIT:
        sys.exit()

    if event.type == KEYDOWN:
      if event.key == K_ESCAPE:
        sys.exit()