#!/usr/bin/env python from __future__ import division import time import string from random import randint from collections import deque from copy import deepcopy import traceback from common import * import pygame pygame.init() from pygame.locals import * def scale_aspect((source_width, source_height), (target_width, target_height)): source_aspect = source_width / source_height target_aspect = target_width / target_height if source_aspect > target_aspect: # restrict width width = target_width height = width / source_aspect else: # restrict height height = target_height width = height * source_aspect return (width, height) class SnakeEngine(object): EDGE_COLOR = (255, 255, 255) EDGE_WIDTH = 1 def __init__(self, rows, columns, n_apples, width=800, height=600, fullscreen=False): super(SnakeEngine, self).__init__() flags = 0 if fullscreen: flags |= pygame.FULLSCREEN self.screen = pygame.display.set_mode((width, height), flags) self.width = width self.height = height self.letters = list(string.lowercase) self.letters.reverse() self.bots = {} self.new_game(rows, columns, n_apples) def get_random_position(self): x = randint(0, self.columns - 1) y = randint(0, self.rows - 1) return (x, y) def replace_random(self, old, new): for i in xrange(self.rows * self.columns): x, y = self.get_random_position() if self.board[y][x] == old: self.board[y][x] = new return x, y def new_game(self, rows, columns, n_apples): self.rows = rows self.columns = columns # make board self.board = [[Squares.EMPTY for x in xrange(columns)] for y in xrange(rows)] for i in xrange(n_apples): x, y = self.get_random_position() self.board[y][x] = Squares.APPLE # make board surface self.board_width, self.board_height = scale_aspect( (columns, rows), (self.width, self.height) ) self.surface = pygame.Surface((self.board_width, self.board_height)) # load sprites xscale = self.board_width / self.columns yscale = self.board_height / self.rows def load_image(image): new_size = scale_aspect(image.get_size(), (xscale, yscale)) return pygame.transform.smoothscale(image, new_size) self.apple = load_image(Sprites.APPLE) self.eyes = load_image(Sprites.EYES) def add_bot(self, bot, colour=None): """ A bot is a callable object, with this method signature: def bot_callable( board=[[cell for cell in row] for row in board], position=(snake_x, snake_y) ): return random.choice('RULD') """ letter = self.letters.pop() position = self.replace_random(Squares.EMPTY, letter.upper()) if position is None: raise KeyError, "Could not insert snake into the board." if colour is None: colour = (randint(0, 255), randint(0, 255), randint(0, 255)) self.bots[letter] = [bot, colour, deque([position])] return letter def remove_bot(self, letter): letter = letter.lower() for row in self.board: for x, cell in enumerate(row): if cell.lower() == letter: row[x] = Squares.EMPTY del self.bots[letter] def draw_board(self): xscale = self.board_width / self.columns yscale = self.board_height / self.rows # Draw grid. for y, row in enumerate(self.board): for x, cell in enumerate(row): left = int(x * xscale) top = int(y * yscale) w = int((x + 1) * xscale) - left h = int((y + 1) * yscale) - top r = Rect(left, top, w, h) # Draw a square. pygame.draw.rect(self.surface, self.EDGE_COLOR, r, self.EDGE_WIDTH) # Draw the things on the square. if cell == Squares.APPLE: self.surface.blit(self.apple, r.topleft) elif cell.isalpha(): # Snake... colour = self.bots[cell.lower()][1] self.surface.fill(colour, r) if cell.isupper(): # Snake head self.surface.blit(self.eyes, r.topleft) def update_snakes(self, directions_id=id(directions)): assert id(directions) == directions_id, \ "The common.directions dictionary has been modified since startup..." for letter, (bot, colour, path) in self.bots.items(): board = deepcopy(self.board) try: x, y = path[-1] d = bot(board, (x, y)) # Sanity checking... assert isinstance(d, basestring), \ "Return value should be a string." d = d.upper() assert d in directions, "Return value should be 'U', 'D', 'L' or 'R'." # Get new position. dx, dy = directions[d] nx = x + dx ny = y + dy if ny < 0 or ny >= self.rows or nx < 0 or nx >= self.columns: self.remove_bot(letter) continue oldcell = self.board[ny][nx] if oldcell in (Squares.EMPTY, Squares.APPLE): # Move snake forward. self.board[ny][nx] = letter.upper() path.append((nx, ny)) # Make old head into body. self.board[y][x] = letter.lower() if oldcell == Squares.APPLE: # Add in an apple to compensate. self.replace_random(Squares.EMPTY, Squares.APPLE) else: # Remove last part of snake. ox, oy = path.popleft() self.board[oy][ox] = Squares.EMPTY else: self.remove_bot(letter) except: print "Exception in bot %s (%s):" % (letter.upper(), bot) print '-'*60 traceback.print_exc() print '-'*60 self.remove_bot(letter) def run(self): clock = pygame.time.Clock() running = True while running and self.bots: for event in pygame.event.get(): if event.type == pygame.QUIT or \ (event.type == pygame.KEYDOWN and event.key == K_ESCAPE): running = False break if not running: break # Clear the screen. self.screen.fill((0, 0, 0)) self.surface.fill((0, 0, 0)) # Draw the board. self.draw_board() # Center the board. x = (self.width - self.board_width) / 2 y = (self.height - self.board_height) / 2 self.screen.blit(self.surface, (x, y)) # Update the display. pygame.display.flip() clock.tick(20) # Let the snakes move! self.update_snakes() if running: time.sleep(2) # Early window close, late process cleanup. pygame.display.quit() if __name__ == '__main__': from bots import * from oldbot import BotWrapper game = SnakeEngine(25, 25, 50) game.add_bot(right_bot) game.add_bot(random_bot) game.add_bot(random_bounds_bot) game.add_bot(random_square_bot) game.add_bot(BotWrapper('oldbots/peter.py')) game.run()