python中如何创建一只小蛇

在Python中创建一只小蛇的核心步骤包括：设置游戏窗口、创建蛇的初始位置和身体、实现蛇的移动、设置食物、处理碰撞检测、更新得分和游戏结束条件。要实现这些步骤，可以使用Pygame库。以下是详细的步骤和代码示例。

一、安装Pygame库

在开始编写代码之前，首先需要确保Pygame库已经安装。可以通过以下命令进行安装：

pip install pygame

二、设置游戏窗口

首先，需要设置游戏窗口的大小和标题，并初始化Pygame。

import pygame
import time
import random
pygame.init()
设置窗口大小
window_x = 720
window_y = 480
初始化游戏窗口
pygame.display.set_caption('Snake Game')
game_window = pygame.display.set_mode((window_x, window_y))
定义颜色
black = pygame.Color(0, 0, 0)
white = pygame.Color(255, 255, 255)
red = pygame.Color(255, 0, 0)
green = pygame.Color(0, 255, 0)
blue = pygame.Color(0, 0, 255)
设置FPS
fps = pygame.time.Clock()

三、创建蛇的初始位置和身体

定义蛇的初始位置和身体结构。

snake_position = [100, 50]
snake_body = [[100, 50], [90, 50], [80, 50], [70, 50]]
设置食物的位置
food_position = [random.randrange(1, (window_x//10)) * 10,
                random.randrange(1, (window_y//10)) * 10]
food_spawn = True
设置初始方向
direction = 'RIGHT'
change_to = direction
设置初始得分
score = 0

四、实现蛇的移动

定义蛇的移动函数和方向控制。

def change_direction(event):
    global change_to
    if event.key == pygame.K_UP and direction != 'DOWN':
        change_to = 'UP'
    elif event.key == pygame.K_DOWN and direction != 'UP':
        change_to = 'DOWN'
    elif event.key == pygame.K_LEFT and direction != 'RIGHT':
        change_to = 'LEFT'
    elif event.key == pygame.K_RIGHT and direction != 'LEFT':
        change_to = 'RIGHT'
def move_snake():
    global direction
    if change_to == 'UP':
        direction = 'UP'
    if change_to == 'DOWN':
        direction = 'DOWN'
    if change_to == 'LEFT':
        direction = 'LEFT'
    if change_to == 'RIGHT':
        direction = 'RIGHT'
    if direction == 'UP':
        snake_position[1] -= 10
    if direction == 'DOWN':
        snake_position[1] += 10
    if direction == 'LEFT':
        snake_position[0] -= 10
    if direction == 'RIGHT':
        snake_position[0] += 10
    # 蛇身体的增长机制
    snake_body.insert(0, list(snake_position))
    if snake_position == food_position:
        global score
        score += 10
        global food_spawn
        food_spawn = False
    else:
        snake_body.pop()
    if not food_spawn:
        food_position[0] = random.randrange(1, (window_x//10)) * 10
        food_position[1] = random.randrange(1, (window_y//10)) * 10
    food_spawn = True

五、处理碰撞检测

检测蛇是否碰撞到边界或自身。

def check_collision():
    # 撞墙检测
    if snake_position[0] < 0 or snake_position[0] > window_x-10:
        return True
    if snake_position[1] < 0 or snake_position[1] > window_y-10:
        return True
    # 撞自己检测
    for block in snake_body[1:]:
        if snake_position == block:
            return True
    return False

六、更新得分和游戏结束条件

绘制蛇和食物，并显示得分。

def show_score():
    font = pygame.font.SysFont('times new roman', 35)
    score_surface = font.render('Score : ' + str(score), True, white)
    score_rect = score_surface.get_rect()
    score_rect.midtop = (window_x/10, 15)
    game_window.blit(score_surface, score_rect)
def game_over():
    font = pygame.font.SysFont('times new roman', 50)
    game_over_surface = font.render('Your Score is : ' + str(score), True, red)
    game_over_rect = game_over_surface.get_rect()
    game_over_rect.midtop = (window_x/2, window_y/4)
    game_window.blit(game_over_surface, game_over_rect)
    pygame.display.flip()
    time.sleep(2)
    pygame.quit()
    quit()

七、主循环

将所有功能结合在主循环中。

while True:
    for event in pygame.event.get():
        if event.type == pygame.KEYDOWN:
            change_direction(event)
        if event.type == pygame.QUIT:
            pygame.quit()
            quit()
    move_snake()
    game_window.fill(black)
    for pos in snake_body:
        pygame.draw.rect(game_window, green, pygame.Rect(pos[0], pos[1], 10, 10))
    pygame.draw.rect(game_window, white, pygame.Rect(food_position[0], food_position[1], 10, 10))
    if check_collision():
        game_over()
    show_score()
    pygame.display.update()
    fps.tick(25)