Drawing the patterns of N players' go stones placed in a spiral

spiralmelee.py

import numpy as np, PIL
from PIL import Image
from queue import Queue

def within(board, coor):
	return coor[0] >= 0 and coor[1] >= 0 and coor[0] < board.shape[0] and coor[1] < board.shape[1]
def get_neighbors(coor):
	return [(coor[0] - 1, coor[1]), (coor[0] + 1, coor[1]), (coor[0], coor[1] - 1), (coor[0], coor[1] + 1)]
def next_diamond_coor(coor):
	# Center
	if coor == (0, 0):
		return (0, 1)
	# Skip to next layer
	if coor[0] == -1 and coor[1] >= 0:
		return (0, coor[1] + 2)
	# right-down
	if coor[0] >= 0 and coor[1] > 0:
		return (coor[0] + 1, coor[1] - 1)
	# left-down
	if coor[0] > 0 and coor[1] <= 0:
		return (coor[0] - 1, coor[1] - 1)
	# left-up
	if coor[0] <= 0 and coor[1] < 0:
		return (coor[0] - 1, coor[1] + 1)
	# right-up
	return (coor[0] + 1, coor[1] + 1)
def next_square_coor(coor):
	x = coor[0]
	y = coor[1]
	# up to next layer
	if x == -y and x <= 0 and y >= 0:
		return (x, y + 1)
	# right
	if y > 0 and x > -y and x < y:
		return (x + 1, y)
	# down
	if x > 0 and y > -x and y <= x:
		return (x, y - 1)
	# left
	if y < 0 and x > y and x <= -y:
		return (x - 1, y)
	# up
	return (x, y + 1)
	
	
def capture_check(board, coor):
	if not within(board, coor):
		return set()
	if board[coor] == -1:
		return set()
	queue = Queue()
	queue.put(coor)
	seen = set()
	seen.add(coor)
	while not queue.empty():
		current = queue.get()
		for neighbor in get_neighbors(current):
			if not within(board, neighbor):
				return set()
			if board[neighbor] == -1:
				return set()
			if neighbor in seen:
				continue
			if board[neighbor] == board[current]:
				queue.put(neighbor)
				seen.add(neighbor)
	return seen

# definitions
player_count = 7
bound = 200

i = 0
coor = (0, 0)
board = np.full((bound * 2 + 1, bound * 2 + 1), -1)
while abs(coor[0]) <= bound and abs(coor[1]) <= bound:
	arr_coor = (bound + coor[0], bound + coor[1])
	board[arr_coor] = i % player_count
	captures = set()
	neighbors = get_neighbors(arr_coor)
	for neighbor in neighbors:
		captures = captures.union(capture_check(board, neighbor))
	for capture in captures:
		board[capture] = -1
	i += 1
	coor = next_diamond_coor(coor)

im = Image.new('RGB', board.shape)
for index, x in np.ndenumerate(board):
	if x != -1:
		im.putpixel(index, (255, 255, 255))
im.save('output.png')