#! /opt/alt/python36/bin/python3.6
"""
A curses-based version of Conway's Game of Life.
An empty board will be displayed, and the following commands are available:
E : Erase the board
R : Fill the board randomly
S : Step for a single generation
C : Update continuously until a key is struck
Q : Quit
Cursor keys : Move the cursor around the board
Space or Enter : Toggle the contents of the cursor's position
Contributed by Andrew Kuchling, Mouse support and color by Dafydd Crosby.
"""
import curses
import random
class LifeBoard:
"""Encapsulates a Life board
Attributes:
X,Y : horizontal and vertical size of the board
state : dictionary mapping (x,y) to 0 or 1
Methods:
display(update_board) -- If update_board is true, compute the
next generation. Then display the state
of the board and refresh the screen.
erase() -- clear the entire board
make_random() -- fill the board randomly
set(y,x) -- set the given cell to Live; doesn't refresh the screen
toggle(y,x) -- change the given cell from live to dead, or vice
versa, and refresh the screen display
"""
def __init__(self, scr, char=ord('*')):
"""Create a new LifeBoard instance.
scr -- curses screen object to use for display
char -- character used to render live cells (default: '*')
"""
self.state = {}
self.scr = scr
Y, X = self.scr.getmaxyx()
self.X, self.Y = X - 2, Y - 2 - 1
self.char = char
self.scr.clear()
# Draw a border around the board
border_line = '+' + (self.X * '-') + '+'
self.scr.addstr(0, 0, border_line)
self.scr.addstr(self.Y + 1, 0, border_line)
for y in range(0, self.Y):
self.scr.addstr(1 + y, 0, '|')
self.scr.addstr(1 + y, self.X + 1, '|')
self.scr.refresh()
def set(self, y, x):
"""Set a cell to the live state"""
if x < 0 or self.X <= x or y < 0 or self.Y <= y:
raise ValueError("Coordinates out of range %i,%i" % (y, x))
self.state[x, y] = 1
def toggle(self, y, x):
"""Toggle a cell's state between live and dead"""
if x < 0 or self.X <= x or y < 0 or self.Y <= y:
raise ValueError("Coordinates out of range %i,%i" % (y, x))
if (x, y) in self.state:
del self.state[x, y]
self.scr.addch(y + 1, x + 1, ' ')
else:
self.state[x, y] = 1
if curses.has_colors():
# Let's pick a random color!
self.scr.attrset(curses.color_pair(random.randrange(1, 7)))
self.scr.addch(y + 1, x + 1, self.char)
self.scr.attrset(0)
self.scr.refresh()
def erase(self):
"""Clear the entire board and update the board display"""
self.state = {}
self.display(update_board=False)
def display(self, update_board=True):
"""Display the whole board, optionally computing one generation"""
M, N = self.X, self.Y
if not update_board:
for i in range(0, M):
for j in range(0, N):
if (i, j) in self.state:
self.scr.addch(j + 1, i + 1, self.char)
else:
self.scr.addch(j + 1, i + 1, ' ')
self.scr.refresh()
return
d = {}
self.boring = 1
for i in range(0, M):
L = range(max(0, i - 1), min(M, i + 2))
for j in range(0, N):
s = 0
live = (i, j) in self.state
for k in range(max(0, j - 1), min(N, j + 2)):
for l in L:
if (l, k) in self.state:
s += 1
s -= live
if s == 3:
# Birth
d[i, j] = 1
if curses.has_colors():
# Let's pick a random color!
self.scr.attrset(curses.color_pair(
random.randrange(1, 7)))
self.scr.addch(j + 1, i + 1, self.char)
self.scr.attrset(0)
if not live:
self.boring = 0
elif s == 2 and live:
# Survival
d[i, j] = 1
elif live:
# Death
self.scr.addch(j + 1, i + 1, ' ')
self.boring = 0
self.state = d
self.scr.refresh()
def make_random(self):
"Fill the board with a random pattern"
self.state = {}
for i in range(0, self.X):
for j in range(0, self.Y):
if random.random() > 0.5:
self.set(j, i)
def erase_menu(stdscr, menu_y):
"Clear the space where the menu resides"
stdscr.move(menu_y, 0)
stdscr.clrtoeol()
stdscr.move(menu_y + 1, 0)
stdscr.clrtoeol()
def display_menu(stdscr, menu_y):
"Display the menu of possible keystroke commands"
erase_menu(stdscr, menu_y)
# If color, then light the menu up :-)
if curses.has_colors():
stdscr.attrset(curses.color_pair(1))
stdscr.addstr(menu_y, 4,
'Use the cursor keys to move, and space or Enter to toggle a cell.')
stdscr.addstr(menu_y + 1, 4,
'E)rase the board, R)andom fill, S)tep once or C)ontinuously, Q)uit')
stdscr.attrset(0)
def keyloop(stdscr):
# Clear the screen and display the menu of keys
stdscr.clear()
stdscr_y, stdscr_x = stdscr.getmaxyx()
menu_y = (stdscr_y - 3) - 1
display_menu(stdscr, menu_y)
# If color, then initialize the color pairs
if curses.has_colors():
curses.init_pair(1, curses.COLOR_BLUE, 0)
curses.init_pair(2, curses.COLOR_CYAN, 0)
curses.init_pair(3, curses.COLOR_GREEN, 0)
curses.init_pair(4, curses.COLOR_MAGENTA, 0)
curses.init_pair(5, curses.COLOR_RED, 0)
curses.init_pair(6, curses.COLOR_YELLOW, 0)
curses.init_pair(7, curses.COLOR_WHITE, 0)
# Set up the mask to listen for mouse events
curses.mousemask(curses.BUTTON1_CLICKED)
# Allocate a subwindow for the Life board and create the board object
subwin = stdscr.subwin(stdscr_y - 3, stdscr_x, 0, 0)
board = LifeBoard(subwin, char=ord('*'))
board.display(update_board=False)
# xpos, ypos are the cursor's position
xpos, ypos = board.X // 2, board.Y // 2
# Main loop:
while True:
stdscr.move(1 + ypos, 1 + xpos) # Move the cursor
c = stdscr.getch() # Get a keystroke
if 0 < c < 256:
c = chr(c)
if c in ' \n':
board.toggle(ypos, xpos)
elif c in 'Cc':
erase_menu(stdscr, menu_y)
stdscr.addstr(menu_y, 6, ' Hit any key to stop continuously '
'updating the screen.')
stdscr.refresh()
# Activate nodelay mode; getch() will return -1
# if no keystroke is available, instead of waiting.
stdscr.nodelay(1)
while True:
c = stdscr.getch()
if c != -1:
break
stdscr.addstr(0, 0, '/')
stdscr.refresh()
board.display()
stdscr.addstr(0, 0, '+')
stdscr.refresh()
stdscr.nodelay(0) # Disable nodelay mode
display_menu(stdscr, menu_y)
elif c in 'Ee':
board.erase()
elif c in 'Qq':
break
elif c in 'Rr':
board.make_random()
board.display(update_board=False)
elif c in 'Ss':
board.display()
else:
# Ignore incorrect keys
pass
elif c == curses.KEY_UP and ypos > 0:
ypos -= 1
elif c == curses.KEY_DOWN and ypos + 1 < board.Y:
ypos += 1
elif c == curses.KEY_LEFT and xpos > 0:
xpos -= 1
elif c == curses.KEY_RIGHT and xpos + 1 < board.X:
xpos += 1
elif c == curses.KEY_MOUSE:
mouse_id, mouse_x, mouse_y, mouse_z, button_state = curses.getmouse()
if (mouse_x > 0 and mouse_x < board.X + 1 and
mouse_y > 0 and mouse_y < board.Y + 1):
xpos = mouse_x - 1
ypos = mouse_y - 1
board.toggle(ypos, xpos)
else:
# They've clicked outside the board
curses.flash()
else:
# Ignore incorrect keys
pass
def main(stdscr):
keyloop(stdscr) # Enter the main loop
if __name__ == '__main__':
curses.wrapper(main)