Edit File: life.py
#! /usr/bin/python2.7 # life.py -- A curses-based version of Conway's Game of Life. # Contributed by AMK # # 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 # # TODO : # Support the mouse # Use colour if available # Make board updates faster # import random, string, traceback import curses 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 makeRandom() -- 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 self.state.has_key( (x,y) ): del self.state[x,y] self.scr.addch(y+1, x+1, ' ') else: self.state[x,y] = 1 self.scr.addch(y+1, x+1, self.char) 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 self.state.has_key( (i,j) ): 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 = self.state.has_key( (i,j) ) for k in range( max(0, j-1), min(N, j+2) ): for l in L: if self.state.has_key( (l,k) ): s += 1 s -= live if s == 3: # Birth d[i,j] = 1 self.scr.addch(j+1, i+1, self.char) if not live: self.boring = 0 elif s == 2 and live: d[i,j] = 1 # Survival elif live: # Death self.scr.addch(j+1, i+1, ' ') self.boring = 0 self.state = d self.scr.refresh() def makeRandom(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) 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') 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) # 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 (1): 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 (1): 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.makeRandom() board.display(update_board=False) elif c in 'Ss': board.display() else: pass # Ignore incorrect keys elif c == curses.KEY_UP and ypos>0: ypos -= 1 elif c == curses.KEY_DOWN and ypos<board.Y-1: ypos += 1 elif c == curses.KEY_LEFT and xpos>0: xpos -= 1 elif c == curses.KEY_RIGHT and xpos<board.X-1: xpos += 1 else: # Ignore incorrect keys pass def main(stdscr): keyloop(stdscr) # Enter the main loop if __name__ == '__main__': curses.wrapper(main)