1#!/usr/bin/env python 2# life.py -- A curses-based version of Conway's Game of Life. 3# Contributed by AMK 4# 5# An empty board will be displayed, and the following commands are available: 6# E : Erase the board 7# R : Fill the board randomly 8# S : Step for a single generation 9# C : Update continuously until a key is struck 10# Q : Quit 11# Cursor keys : Move the cursor around the board 12# Space or Enter : Toggle the contents of the cursor's position 13# 14# TODO : 15# Support the mouse 16# Use colour if available 17# Make board updates faster 18# 19 20import random, string, traceback 21import curses 22 23class LifeBoard: 24 """Encapsulates a Life board 25 26 Attributes: 27 X,Y : horizontal and vertical size of the board 28 state : dictionary mapping (x,y) to 0 or 1 29 30 Methods: 31 display(update_board) -- If update_board is true, compute the 32 next generation. Then display the state 33 of the board and refresh the screen. 34 erase() -- clear the entire board 35 makeRandom() -- fill the board randomly 36 set(y,x) -- set the given cell to Live; doesn't refresh the screen 37 toggle(y,x) -- change the given cell from live to dead, or vice 38 versa, and refresh the screen display 39 40 """ 41 def __init__(self, scr, char=ord('*')): 42 """Create a new LifeBoard instance. 43 44 scr -- curses screen object to use for display 45 char -- character used to render live cells (default: '*') 46 """ 47 self.state = {} 48 self.scr = scr 49 Y, X = self.scr.getmaxyx() 50 self.X, self.Y = X-2, Y-2-1 51 self.char = char 52 self.scr.clear() 53 54 # Draw a border around the board 55 border_line = '+'+(self.X*'-')+'+' 56 self.scr.addstr(0, 0, border_line) 57 self.scr.addstr(self.Y+1,0, border_line) 58 for y in range(0, self.Y): 59 self.scr.addstr(1+y, 0, '|') 60 self.scr.addstr(1+y, self.X+1, '|') 61 self.scr.refresh() 62 63 def set(self, y, x): 64 """Set a cell to the live state""" 65 if x<0 or self.X<=x or y<0 or self.Y<=y: 66 raise ValueError, "Coordinates out of range %i,%i"% (y,x) 67 self.state[x,y] = 1 68 69 def toggle(self, y, x): 70 """Toggle a cell's state between live and dead""" 71 if x<0 or self.X<=x or y<0 or self.Y<=y: 72 raise ValueError, "Coordinates out of range %i,%i"% (y,x) 73 if self.state.has_key( (x,y) ): 74 del self.state[x,y] 75 self.scr.addch(y+1, x+1, ' ') 76 else: 77 self.state[x,y] = 1 78 self.scr.addch(y+1, x+1, self.char) 79 self.scr.refresh() 80 81 def erase(self): 82 """Clear the entire board and update the board display""" 83 self.state = {} 84 self.display(update_board=False) 85 86 def display(self, update_board=True): 87 """Display the whole board, optionally computing one generation""" 88 M,N = self.X, self.Y 89 if not update_board: 90 for i in range(0, M): 91 for j in range(0, N): 92 if self.state.has_key( (i,j) ): 93 self.scr.addch(j+1, i+1, self.char) 94 else: 95 self.scr.addch(j+1, i+1, ' ') 96 self.scr.refresh() 97 return 98 99 d = {} 100 self.boring = 1 101 for i in range(0, M): 102 L = range( max(0, i-1), min(M, i+2) ) 103 for j in range(0, N): 104 s = 0 105 live = self.state.has_key( (i,j) ) 106 for k in range( max(0, j-1), min(N, j+2) ): 107 for l in L: 108 if self.state.has_key( (l,k) ): 109 s += 1 110 s -= live 111 if s == 3: 112 # Birth 113 d[i,j] = 1 114 self.scr.addch(j+1, i+1, self.char) 115 if not live: self.boring = 0 116 elif s == 2 and live: d[i,j] = 1 # Survival 117 elif live: 118 # Death 119 self.scr.addch(j+1, i+1, ' ') 120 self.boring = 0 121 self.state = d 122 self.scr.refresh() 123 124 def makeRandom(self): 125 "Fill the board with a random pattern" 126 self.state = {} 127 for i in range(0, self.X): 128 for j in range(0, self.Y): 129 if random.random() > 0.5: 130 self.set(j,i) 131 132 133def erase_menu(stdscr, menu_y): 134 "Clear the space where the menu resides" 135 stdscr.move(menu_y, 0) 136 stdscr.clrtoeol() 137 stdscr.move(menu_y+1, 0) 138 stdscr.clrtoeol() 139 140def display_menu(stdscr, menu_y): 141 "Display the menu of possible keystroke commands" 142 erase_menu(stdscr, menu_y) 143 stdscr.addstr(menu_y, 4, 144 'Use the cursor keys to move, and space or Enter to toggle a cell.') 145 stdscr.addstr(menu_y+1, 4, 146 'E)rase the board, R)andom fill, S)tep once or C)ontinuously, Q)uit') 147 148def keyloop(stdscr): 149 # Clear the screen and display the menu of keys 150 stdscr.clear() 151 stdscr_y, stdscr_x = stdscr.getmaxyx() 152 menu_y = (stdscr_y-3)-1 153 display_menu(stdscr, menu_y) 154 155 # Allocate a subwindow for the Life board and create the board object 156 subwin = stdscr.subwin(stdscr_y-3, stdscr_x, 0, 0) 157 board = LifeBoard(subwin, char=ord('*')) 158 board.display(update_board=False) 159 160 # xpos, ypos are the cursor's position 161 xpos, ypos = board.X//2, board.Y//2 162 163 # Main loop: 164 while (1): 165 stdscr.move(1+ypos, 1+xpos) # Move the cursor 166 c = stdscr.getch() # Get a keystroke 167 if 0<c<256: 168 c = chr(c) 169 if c in ' \n': 170 board.toggle(ypos, xpos) 171 elif c in 'Cc': 172 erase_menu(stdscr, menu_y) 173 stdscr.addstr(menu_y, 6, ' Hit any key to stop continuously ' 174 'updating the screen.') 175 stdscr.refresh() 176 # Activate nodelay mode; getch() will return -1 177 # if no keystroke is available, instead of waiting. 178 stdscr.nodelay(1) 179 while (1): 180 c = stdscr.getch() 181 if c != -1: 182 break 183 stdscr.addstr(0,0, '/') 184 stdscr.refresh() 185 board.display() 186 stdscr.addstr(0,0, '+') 187 stdscr.refresh() 188 189 stdscr.nodelay(0) # Disable nodelay mode 190 display_menu(stdscr, menu_y) 191 192 elif c in 'Ee': 193 board.erase() 194 elif c in 'Qq': 195 break 196 elif c in 'Rr': 197 board.makeRandom() 198 board.display(update_board=False) 199 elif c in 'Ss': 200 board.display() 201 else: pass # Ignore incorrect keys 202 elif c == curses.KEY_UP and ypos>0: ypos -= 1 203 elif c == curses.KEY_DOWN and ypos<board.Y-1: ypos += 1 204 elif c == curses.KEY_LEFT and xpos>0: xpos -= 1 205 elif c == curses.KEY_RIGHT and xpos<board.X-1: xpos += 1 206 else: 207 # Ignore incorrect keys 208 pass 209 210 211def main(stdscr): 212 keyloop(stdscr) # Enter the main loop 213 214 215if __name__ == '__main__': 216 curses.wrapper(main) 217