ipycanvas: John Conway's Game Of Life¶

%pip install -q ipycanvas

import asyncio

import numpy as np
from ipycanvas import RoughCanvas, hold_canvas

def life_step(x):
    """Game of life step"""
    nbrs_count = sum(
        np.roll(np.roll(x, i, 0), j, 1)
        for i in (-1, 0, 1)
        for j in (-1, 0, 1)
        if (i != 0 or j != 0)
    )
    return (nbrs_count == 3) | (x & (nbrs_count == 2))

def draw(x, canvas, color="black"):
    with hold_canvas(canvas):
        canvas.clear()
        canvas.fill_style = "#FFF0C9"
        canvas.stroke_style = "white"
        canvas.fill_rect(0, 0, canvas.width, canvas.height)

        canvas.fill_style = color
        canvas.stroke_style = color

        living_cells = np.where(x)

        rects_x = living_cells[0] * n_pixels
        rects_y = living_cells[1] * n_pixels

        canvas.fill_rects(rects_x, rects_y, n_pixels)
        canvas.stroke_rects(rects_x, rects_y, n_pixels)

# fmt: off
glider_gun =\
[[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0],
 [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0],
 [0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1],
 [0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1],
 [1,1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
 [1,1,0,0,0,0,0,0,0,0,1,0,0,0,1,0,1,1,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0],
 [0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0],
 [0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
 [0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]]

# fmt: on
x = np.zeros((50, 70), dtype=bool)
x[1:10, 1:37] = glider_gun

n_pixels = 15

canvas = RoughCanvas(width=x.shape[0] * n_pixels, height=x.shape[1] * n_pixels)
canvas.fill_style = "#FFF0C9"
canvas.stroke_style = "white"
canvas.fill_rect(0, 0, canvas.width, canvas.height)

canvas

draw(x, canvas, "#5770B3")

for _ in range(1_000):
    x = life_step(x)
    draw(x, canvas, "#5770B3")

    await asyncio.sleep(0.1)