from math import log, sin, cos, pi
from kandinsky import fill_rect, get_pixel, set_pixel
from ion import keydown
import ion


COUL = (0,0,0), (222,20,16), (255,166,0), (255,243,206)
W, H = 320, 222

_state = [1]
def rng_seed(s):
    _state[0] = s & 0xFFFFFFFF
def rng():
    x = _state[0]
    x ^= (x << 13) & 0xFFFFFFFF
    x ^= (x >> 17) & 0xFFFFFFFF
    x ^= (x << 5)  & 0xFFFFFFFF
    _state[0] = x & 0xFFFFFFFF
    return _state[0] / 4294967296.0

N_POINTS = 800
DROTAT   = 2 * pi / 900
SCALE    = 12

def draw_galaxy(rotat):
    rng_seed(1)
    for _ in range(N_POINTS):
        r = rng()
        dist  = log(r + 4.54e-5)
        angle = 2 * pi * rng()

        u = 6 * dist * sin(angle)
        v = 5 * dist * cos(angle)

        cd = cos(3 * dist + rotat)
        sd = sin(3 * dist + rotat)
        x =  u * cd + v * sd
        y = -u * sd + v * cd
        y += rng() * 3 - 1.5

        xt = 1.4 * x + 0.6 * y
        yt = 0.2 * x + 0.8 * y

        px = int(160 + xt * SCALE)
        py = int(111 + yt * SCALE)

        if 0 <= px < W and 0 <= py < H:
            cur = COUL.index(get_pixel(px, py))
            if cur < 3:
                set_pixel(px, py, COUL[cur + 1])

fill_rect(0, 0, W, H, COUL[0])
rotat = 0.0

while True:
    fill_rect(0, 0, W, H, COUL[0])
    draw_galaxy(rotat)
    rotat += DROTAT
    if rotat >= 2 * pi: rotat = 0.0
    if keydown(ion.KEY_HOME) or keydown(ion.KEY_BACK):
        break