Game of life¶

import numpy as np
import holoviews as hv
import panel as pn

from holoviews import opts
from holoviews.streams import Tap, Counter, DoubleTap
from scipy.signal import convolve2d

hv.extension('bokeh')

diehard = [[0, 0, 0, 0, 0, 0, 1, 0],
           [1, 1, 0, 0, 0, 0, 0, 0],
           [0, 1, 0, 0, 0, 1, 1, 1]]

boat = [[1, 1, 0],
        [1, 0, 1],
        [0, 1, 0]]

r_pentomino = [[0, 1, 1],
               [1, 1, 0],
               [0, 1, 0]]

beacon = [[0, 0, 1, 1],
          [0, 0, 1, 1],
          [1, 1, 0, 0],
          [1, 1, 0, 0]]

acorn = [[0, 1, 0, 0, 0, 0, 0],
         [0, 0, 0, 1, 0, 0, 0],
         [1, 1, 0, 0, 1, 1, 1]]

spaceship = [[0, 0, 1, 1, 0],
             [1, 1, 0, 1, 1],
             [1, 1, 1, 1, 0],
             [0, 1, 1, 0, 0]]

block_switch_engine = [[0, 0, 0, 0, 0, 0, 1, 0],
                       [0, 0, 0, 0, 1, 0, 1, 1],
                       [0, 0, 0, 0, 1, 0, 1, 0],
                       [0, 0, 0, 0, 1, 0, 0, 0],
                       [0, 0, 1, 0, 0, 0, 0, 0],
                       [1, 0, 1, 0, 0, 0, 0, 0]]

glider = [[1, 0, 0], [0, 1, 1], [1, 1, 0]]

unbounded = [[1, 1, 1, 0, 1],
            [1, 0, 0, 0, 0],
            [0, 0, 0, 1, 1],
            [0, 1, 1, 0, 1],
            [1, 0, 1, 0, 1]]

shapes = {'Glider': glider, 'Block Switch Engine': block_switch_engine,
          'Spaceship': spaceship, 'Acorn': acorn, 'Beacon': beacon,
          'Diehard': diehard, 'Unbounded': unbounded}

def step(X):
    nbrs_count = convolve2d(X, np.ones((3, 3)), mode='same', boundary='wrap') - X
    return (nbrs_count == 3) | (X & (nbrs_count == 2))

def update(pattern, counter, x, y):
    if x and y:
        pattern = np.array(shapes[pattern])
        r, c = pattern.shape
        y, x = img.sheet2matrixidx(x,y)
        img.data[y:y+r,x:x+c] = pattern[::-1]
    else:
        img.data = step(img.data)
    return hv.Image(img)

# Set up plot which advances on counter and adds pattern on tap
title = 'Game of Life - Tap to place pattern, Doubletap to clear'
img = hv.Image(np.zeros((100, 200), dtype=np.uint8))
counter, tap = Counter(transient=True), Tap(transient=True),
pattern_dim = hv.Dimension('Pattern', values=sorted(shapes.keys()))
dmap = hv.DynamicMap(update, kdims=[pattern_dim], streams=[counter, tap])

plot = dmap.opts(
    opts.Image(cmap='gray', clim=(0, 1), toolbar=None, responsive=True,
               min_height=800, title=title, xaxis=None, yaxis=None)
)

# Add callback to clear on double tap
def reset_data(x, y):
    img.data[:] = 0

reset = DoubleTap(transient=True, source=plot)
reset.add_subscriber(reset_data)

# Set up Panel app and periodic callback
panel = pn.pane.HoloViews(plot, center=True, widget_location='right')

def advance():
    counter.event(counter=counter.counter+1)
panel.add_periodic_callback(advance, 50)

panel.servable('Game of Life')