《Flappy Bird》 Python Clone 学习之路

背景

准备

获取游戏资源包

工程搭建

代码编写

背景

前阵学习了一些python的简单语法，前两天又了解到有个pygame库可以用python写些简单的2D游戏，昨晚无意中从GitHub上搜的了一个Flappy Bird用pygame写的源码，copy在电脑上竟然可以完美运行，这激起我的学习兴趣，也想完全从头做一个一样的，学习和成长的过程不就是一个在不断重复和模仿别人的过程嘛

准备

python环境（强烈建议安装32位python）
pygame库（cmd 下输入 pip install pygame即可）
---------游戏图片和音效直接下载的话（资源包下载点我）可跳过以下步骤直接从工程搭建开始-----------------------
opencv-python 库用于截图（cmd 下输入 pip install opencv-python）
游戏资源包（游戏中用到的图片文件和音效文件）

（1、 2自行百度，下面主要介绍一下资源包的获取）

获取游戏资源包

能力和精力有限，游戏声音和图片就没有从头学起自己制作了，作者主要目的以学习python为主。

网上下载一个Flappy Bird原版的APK安装包，将.apk后缀改为.zip，然后右键解压（电脑安装了压缩软件，本人用的WinRAR），解压后在\assets\sounds可以找到音频文件，在assets\gfx文件夹下找到atlas.png图片。

可以发现，他讲游戏图片中所有元素都拼到一张图里了，这得需要进行图片分割，打开\res\raw\atlas.txt

可以看到游戏元素图片的在整张拼图的具体信息，下面就是用这个信息进行图片分割提取

从上图看出每行是一张图片信息，

[图片名称，图片宽度（单位像素点），图片高度，图片在整张拼图相对位置x（整张宽度为1），图片在整张拼图相对位置y（整张宽度为1），图片在整张拼图相对宽度x（整张宽度为1），图片在整张拼图相对高度y（整张宽度为1）]

在D盘根目录下新建一个Split文件夹将atlas.png和atlas.txt都拷过去，新建split.py文件，内容如下：

import cv2 as cv
import os
#读取原图
image = cv.imread('atlas.png', -1)
#打印图片形状（高，宽，通道数），高宽的单位是像素数
raw_width, raw_height, _ = image.shape
#创建文件夹
if not os.path.exists("./output/"):os.makedirs("./output/")
#读取txt文件
with open('atlas.txt') as f:for line in f:strs = line.split(" ")filename = strs[0]imgWidth = int(strs[1])imgHeight = int(strs[2])imgX = float(strs[3])*raw_widthimgY = float(strs[4])*raw_height# 对感兴趣区域进行截图imageROI=image[int(imgY):int(imgY+imgHeight),int(imgX):int(imgX+imgWidth)]# 截图部分生成新图片cv.imwrite("./output/"+filename+".png", imageROI)

执行完成后就在新产生的output文件夹里就会有分割出所需图像

最后音频文件解压出来的ogg格式，防止在有的Windows系统中没有响应ogg播放软件，最好用转换软件（比如格式工厂）将ogg转换成wav格式

至此，所有资源包都已获取，资源包下载点我

工程搭建

新建一个FlappyBird文件夹作为工程文件夹，期内新建FlappyBird.py文件作为代码文件，然后新建assets文件夹，assets文件夹内新建audio文件夹存放音频，sprites文件夹存放图片元素

至此所有准备工作完成，开始撸代码

代码编写

#从迭代器库中调用cycle方法
from itertools import cycle
import random
import sys
import pygame
from pygame.locals import *SCREEN_WIDTH = 288
SCREEN_HEIGHT = 512
# 游戏状态
ANIMATION   = 0
RUNNING     = 1
GAMEOVER    = 2pygame.init()
pygame.display.set_caption("Flappy Bird by GHL")
#设置游戏对话框尺寸
SCREEN = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
#取背景图,抠掉边缘转换
background_day = pygame.image.load('assets/sprites/background-day.png').convert_alpha()
#取小鸟图
bird = [pygame.image.load('assets/sprites/redbird-upflap.png').convert_alpha(),pygame.image.load('assets/sprites/redbird-midflap.png').convert_alpha(),pygame.image.load('assets/sprites/redbird-downflap.png').convert_alpha()
]
# 取数字
number = [pygame.image.load('assets/sprites/0.png').convert_alpha(),pygame.image.load('assets/sprites/1.png').convert_alpha(),pygame.image.load('assets/sprites/2.png').convert_alpha(),pygame.image.load('assets/sprites/3.png').convert_alpha(),pygame.image.load('assets/sprites/4.png').convert_alpha(),pygame.image.load('assets/sprites/5.png').convert_alpha(),pygame.image.load('assets/sprites/6.png').convert_alpha(),pygame.image.load('assets/sprites/7.png').convert_alpha(),pygame.image.load('assets/sprites/8.png').convert_alpha(),pygame.image.load('assets/sprites/9.png').convert_alpha()
]
# 地面图
ground = pygame.image.load('assets/sprites/base.png').convert_alpha()
# 开场动画
message = pygame.image.load('assets/sprites/message.png').convert_alpha()
# 取柱子
pipe_down = pygame.image.load('assets/sprites/pipe-green.png').convert_alpha()
pipe_up = pygame.transform.rotate(pipe_down, 180)
# 取logo
logo = pygame.image.load('assets/sprites/logo.png').convert_alpha()
# 取声音
if "win" in sys.platform:soundExt = ".wav"
else:soundExt = ".ogg"
sound_wing  = pygame.mixer.Sound('assets/audio/wing'+soundExt)
sound_hit   = pygame.mixer.Sound('assets/audio/hit'+soundExt)
sound_point = pygame.mixer.Sound('assets/audio/point'+soundExt)
sound_die   = pygame.mixer.Sound('assets/audio/die'+soundExt)
# 取game over文本
text_game_over = pygame.image.load('assets/sprites/text_game_over.png').convert_alpha()def showScore(score):# 拆分数字scoreDigits = [int(x) for x in list(str(score))]# 计算数字总宽度totalWidth = 0for digit in scoreDigits:totalWidth += number[digit].get_width()# 居中摆放score_x_position = (SCREEN_WIDTH - totalWidth)//2score_y_position = int(0.2 * SCREEN_HEIGHT)# 刷图for digit in scoreDigits:SCREEN.blit(number[digit], (score_x_position, score_y_position))score_x_position += number[digit].get_width()def main():# 创建帧率实例FPS = pygame.time.Clock()# 迭代器 小鸟翅膀 0-1-2-1-0循环wing_position_iter = cycle([0,1,2,1])wing_position = 0# 迭代器 小鸟上下抖动 bird_shake_iter = cycle([0,1,2,3,4,3,2,1,0,-1,-2,-3,-4,-3,-2,-1])bird_shake = 0bird_position = int(0.5 * SCREEN_HEIGHT)      # 小鸟起始高度bird_x_position = int(0.2*SCREEN_WIDTH)            # 小鸟水平位置ground_position = int(0.8 * SCREEN_HEIGHT-bird[0].get_height()) # 地面高度fps_count = 0           # 帧数处理key_down = 0         # 按键按下 gravity = 1             # 重力大小down_velocity = 0        # 下降速度head_direction = 0       # 鸟头方向game_state    = ANIMATION    # 游戏状态pipe_move_distance = SCREEN_WIDTH*4//3+pipe_down.get_width()#管子需要移动的距离pipe_gap = 150           # 管空隙大小pipe2_gap = 150             # 管2空隙大小pipe_x_position = SCREEN_WIDTH     # 柱子水平位置pipe_down_position = 0 # 下柱子管口位置pipe2_x_position = pipe_move_distance     # 柱子水平位置pipe2_up_position = 0pipe2_down_position = 0  # 下柱子管口位置score = 0             # 得分ground_x_position = 0  # 地面水平位置bird_actual_position = 0# 小鸟实际高度# fisrt_fly_no_pipe    = 90 # 开始一段没有柱子while 1:# 获取鼠标按键状态for event in pygame.event.get():      if event.type == QUIT:pygame.quit()sys.exit()if event.type == KEYDOWN and event.key == K_SPACE:if game_state == ANIMATION:game_state = RUNNINGdown_velocity = 0   # 下降速度head_direction = 0   # 鸟头方向fps_count = 0        # 帧数处理score = 0            # 得分pipe_x_position = SCREEN_WIDTH     # 柱子水平位置pipe2_x_position = pipe_move_distance  # 柱子水平位置if game_state == RUNNING:key_down = 6sound_wing.play()if game_state == GAMEOVER:# 小鸟落地后游戏才能重新开始 if bird_actual_position == ground_position:game_state = ANIMATIONbird_position = int(0.5 * SCREEN_HEIGHT)      # 小鸟起始高度# 刷新背景SCREEN.blit(background_day, (0, 0))# 重绘logo大小logo_resize = pygame.transform.scale(logo,(25,25))# 设置左上角iconpygame.display.set_icon(logo_resize)if game_state == ANIMATION:fps_count += 1SCREEN.blit(message,(SCREEN_WIDTH/2-message.get_width()/2, 0.1* SCREEN_HEIGHT))# 草地动起来ground_x_position = -1*((fps_count*4)%(ground.get_width()-SCREEN_WIDTH))SCREEN.blit(ground, (ground_x_position,int(0.8 * SCREEN_HEIGHT)))# 更新翅膀位置，比帧数放慢5倍if fps_count % 5 == 0:wing_position = next(wing_position_iter)# 小鸟上下抖动 bird_shake = next(bird_shake_iter)# 小鸟动起来bird_actual_position = bird_position+bird_shakeSCREEN.blit(bird[wing_position], (bird_x_position, bird_actual_position))         if game_state == RUNNING:# 帧数处理fps_count += 1# 游戏刚开始时候没有柱子空飞一段# if fps_count*4 > SCREEN_WIDTH+pipe_down.get_width(): if 1:# 柱子动起来if pipe_x_position == SCREEN_WIDTH:pipe_down_position    = random.randrange(int(0.3 * SCREEN_HEIGHT),int(0.7 * SCREEN_HEIGHT), 10)pipe_gap  = random.randrange(100,151, 10)pipe_up_position    = pipe_down_position - pipe_gap - pipe_up.get_height()pipe_x_position      = SCREEN_WIDTH-(fps_count*4)%pipe_move_distanceSCREEN.blit(pipe_down, (pipe_x_position,pipe_down_position))SCREEN.blit(pipe_up, (pipe_x_position,pipe_up_position))if fps_count*4 > pipe_move_distance//2:# 柱子2动起来if pipe2_x_position == pipe_move_distance:pipe2_down_position   = random.randrange(int(0.3 * SCREEN_HEIGHT),int(0.7 * SCREEN_HEIGHT), 10)pipe2_gap = random.randrange(100,151, 10)pipe2_up_position   = pipe2_down_position - pipe2_gap - pipe_up.get_height()pipe2_x_position   = pipe_move_distance-pipe_down.get_width()-(fps_count*4-pipe_move_distance//3)%pipe_move_distanceSCREEN.blit(pipe_down, (pipe2_x_position,pipe2_down_position))SCREEN.blit(pipe_up, (pipe2_x_position,pipe2_up_position))# 草地动起来ground_x_position = -1*((fps_count*4)%(ground.get_width()-SCREEN_WIDTH))SCREEN.blit(ground, (ground_x_position,int(0.8 * SCREEN_HEIGHT)))# 更新翅膀位置，比帧数放慢5倍if fps_count % 5 == 0:wing_position = next(wing_position_iter)# 小鸟上下抖动 bird_shake = next(bird_shake_iter)# 小鸟受重力下落, 按键按下则上升if key_down:# 刷新的过程需要key_down递减之0 用几帧画面完成key_down -= 1 bird_position -= 6bird_position = max(0, bird_position)      # 边界检测down_velocity = 0head_direction += 6head_direction = min(24, head_direction)  # 边界检测else:down_velocity += gravitybird_position += down_velocitybird_position = min(bird_position, ground_position)# 边界检测head_direction -= 3head_direction = max(-42, head_direction)   # 边界检测# 调整头的方向bird_head = pygame.transform.rotate(bird[wing_position], head_direction)# 小鸟动起来bird_actual_position = bird_position+bird_shakeSCREEN.blit(bird_head, (bird_x_position, bird_actual_position))# 检测撞地if bird_position == ground_position:game_state = GAMEOVERsound_hit.play()# 检测撞柱子# 小鸟水平位置在柱子管水平宽度内if bird_x_position+bird[0].get_width() > pipe_x_position and \bird_x_position < pipe_x_position+pipe_down.get_width():# 小鸟高度比下管道低或比上管道高if bird_actual_position+bird[0].get_height() > pipe_down_position or \bird_actual_position < pipe_down_position - pipe_gap:game_state = GAMEOVERsound_hit.play()sound_die.play()# 小鸟水平位置在柱子2管水平宽度内if bird_x_position+bird[0].get_width() > pipe2_x_position and \bird_x_position < pipe2_x_position+pipe_down.get_width():# 小鸟高度比下管道低或比上管道高if bird_actual_position+bird[0].get_height() > pipe2_down_position or \bird_actual_position < pipe2_down_position - pipe2_gap:game_state = GAMEOVERsound_hit.play()sound_die.play()# 小鸟飞过管道后壁刷新得分if abs(bird_x_position - (pipe_x_position+pipe_down.get_width() ) ) < 3 or\abs(bird_x_position - (pipe2_x_position+pipe_down.get_width() ) ) < 3:sound_point.play()score += 1showScore(score)if game_state == GAMEOVER:# 调整头的方向bird_head = pygame.transform.rotate(bird[wing_position], -90)SCREEN.blit(pipe_down, (pipe_x_position,pipe_down_position))SCREEN.blit(pipe_up, (pipe_x_position,pipe_up_position))SCREEN.blit(pipe_down, (pipe2_x_position,pipe2_down_position))SCREEN.blit(pipe_up, (pipe2_x_position,pipe2_up_position))SCREEN.blit(ground, (ground_x_position,int(0.8 * SCREEN_HEIGHT)))bird_actual_position += 10bird_actual_position = min(ground_position, bird_actual_position)SCREEN.blit(bird_head, (bird_x_position, bird_actual_position))showScore(score)# 小鸟落地后游戏才能重新开始 if bird_actual_position == ground_position:SCREEN.blit(text_game_over, (SCREEN_WIDTH/2-text_game_over.get_width()/2, 0.4*SCREEN_HEIGHT))# 设置文中logoSCREEN.blit(pygame.image.load('assets/sprites/ghl_white50.png').convert_alpha(), (SCREEN_WIDTH-50,SCREEN_HEIGHT-50))# 图片刷新pygame.display.update()# 设置帧率30帧FPS.tick(30)if __name__ == "__main__":main()

文件不是一天写完的，最终的源码及用到的资源包及用pyinstaller生成的exe，我放在了完整源码及资源包供下载

明天就是中秋了，最后，祝大家中秋节快乐！

2018年9月23日于上海图书馆