【python游戏编程之旅】第五篇---嗷大喵爱吃鱼小游戏开发实例

本系列博客介绍以python+pygame库进行小游戏的开发。有写的不对之处还望各位海涵。

我们一同在前几期的博客中已经学到了很多pygame的基本知识了，现在该做个小游戏实战一下了。

前几期博客链接：

第一篇：初识pygame  http://www.cnblogs.com/msxh/p/4966899.html

第二篇：pygame中的IO、数据  http://www.cnblogs.com/msxh/p/4973003.html

第三篇：pygame事件与设备轮询  http://www.cnblogs.com/msxh/p/4979380.html

第四篇：pygame中加载位图及些常用的数学函数  http://www.cnblogs.com/msxh/p/4990435.html

本次我们要做一个很简单的小游戏：从天上会随机的掉下鱼，你需要使用鼠标操纵猫去接住鱼，丢失一条鱼损失一条命，一共有10条命，同时还要避免接到炸弹。接住鱼会有积分。

游戏效果图如下：

游戏下载地址：http://pan.baidu.com/s/1qWA4xZ2

源代码下载地址：http://pan.baidu.com/s/1i3is15j

还是先上一下完整的源代码吧：

 # -*-coding:utf-8-*- s = '
 #AoDaMiao Like Eating Fish
 import sys, random, time, pygame
 from pygame.locals import *

 def print_text(font, x, y, text, color=(255,255,255)):
     imgText = font.render(text, True, color)
     screen.blit(imgText, (x,y))

 #main program begins
 pygame.init()
 screen = pygame.display.set_mode((600,500))
 pygame.display.set_caption("嗷大喵爱吃鱼！")
 font1 = pygame.font.Font(None, 24)
 font2 = pygame.font.Font(None, 18)
 font3 = pygame.font.Font(None, 34)
 pygame.mouse.set_visible(False)
 white = 255,255,255
 red = 220, 50, 50
 yellow = 230,230,50
 black = 0,0,0
 cat=pygame.image.load("aodamiao_2.png")
 width,height=cat.get_size()
 pic=pygame.transform.scale(cat,(width,height))
 fish=pygame.image.load("fish.png")
 width,height=fish.get_size()
 fish=pygame.transform.smoothscale(fish,(width//3,height//3))
 init=pygame.image.load("init.png")
 lives = 10
 score = 0
 clock_start = 0
 game_over = 1
 mouse_x = mouse_y = 0
 Round =1
 mine=0
 mine_png=pygame.image.load("mine.png")
 cat2=pygame.image.load("aodamiao_3.png")
 flag=0

 pos_x = 300
 pos_y = 410-40

 bomb_x = random.randint(0,500)
 mine_x=random.randint(0,500)
 bomb_y = -50
 vel_y = 0.4
 vel_yy=0.6
 mine_y=-100

 #repeating loop
 while True:
     for event in pygame.event.get():
         if event.type == pygame.QUIT:
             #sys.exit()
             pygame.quit()
             exit()
         elif event.type == MOUSEMOTION:
             mouse_x,mouse_y = event.pos
             move_x,move_y = event.rel
         elif event.type == MOUSEBUTTONUP:
             if game_over:
                 game_over = False
                 lives = 10
                 score = 0
                 Round =1
                 vel_y=0.4
                 mine=0
                 flag=0
                 pic=cat
                 bomb_y = -50

     keys = pygame.key.get_pressed()
     if keys[K_ESCAPE]:
         sys.exit()

     screen.fill((0,0,100))

     if game_over:
         screen.blit(init,(60, 60))
         print_text(font3, 200, 400,"Clicked To Play!")
         print_text(font2, 310, 480,"Copyright@2015 developed by xiaoxiami")
     else:
         #Round setting
         if score >300 and score <600:
              Round=2
         elif score >600 and score <900:
              Round =3
         elif score >900 and score <1200:
              Round=4
         elif score >1200 and score <1500:
              Round =5
         elif score >=1500:
              Round =6
         #draw the Round
         print_text(font1, 280, 0, "Round: " + str(Round))
         #speed setting
         if Round ==1:
             vel_y=0.4
         elif Round ==2:
             vel_y=0.6
         elif Round ==3:
             vel_y=0.8
         elif Round ==4:
             vel_y=1.0
         elif Round ==5:
             vel_y=1.2
         #mine number setting
         #mine=random.randint(1,9)
         #move the fish
         bomb_y += vel_y
         mine_y+=vel_yy

         #has the player missed the fish?
         if bomb_y > 500:
             bomb_x = random.randint(0, 500)
             bomb_y = -50
             lives -= 1
             if lives == 0:
                 game_over = True
         #see if player has caught the fish
         elif bomb_y > pos_y:
             if bomb_x > pos_x-10 and bomb_x < pos_x + 70:
                 score += 10
                 bomb_x = random.randint(0, 500)
                 bomb_y = -50
         if Round >2:
         #has the player missed the mine?
             if mine_y > 500:
                 mine_x = random.randint(0, 500)
                 mine_y = -50
         #see if player has caught the mine
             elif mine_y > pos_y:
                 if mine_x > pos_x and mine_x < pos_x + 40:
                     mine_x = random.randint(0, 500)
                     mine_y = -50
                     lives-=1
                     pic=cat2
                     if lives == 0:
                         game_over = True

         #draw the fish
         screen.blit(fish,(bomb_x,int(bomb_y)))
         #draw the mine
         if Round >2:
             screen.blit(mine_png,(mine_x,int(mine_y)))

         #set cat position
         pos_x = mouse_x
         if pos_x < 0:
             pos_x = 0
         elif pos_x > 510:
             pos_x = 500
         #draw cat
         if lives<5:
             pic=cat2
         screen.blit(pic,(pos_x,pos_y))

     #print # of lives
     print_text(font1, 0, 0, "LIVES: " + str(lives))

     #print score
     print_text(font1, 500, 0, "SCORE: " + str(score))

     pygame.display.update()

关于位图的加载，设备轮询等等的内容我们就不在这里赘述了，不熟悉的可以查看前几期的博客。

为了让游戏更有趣味性，我们设置一下鱼的速度是可以变的。当得到的分数在不同区间的时候，会有不同的速度。（速度会越来快。）详见代码83-107行。

为了判断玩家是否错过鱼或者接到鱼，我们还需要写一个简单的碰撞检测函数：

        #如果错过鱼的话，就重置鱼的位置，给它一个随机的x值，然后生命值   减一
        if bomb_y > 500:
            bomb_x = random.randint(0, 500)
            bomb_y = -50
            lives -= 1
            if lives == 0:
                game_over = True
        #简单碰撞检测函数，查看是否接住鱼
        elif bomb_y > pos_y:
            if bomb_x > pos_x-10 and bomb_x < pos_x + 70:
                score += 10
                bomb_x = random.randint(0, 500)
                bomb_y = -50

同理炸弹的检测和这个是类似的。

if bomb_y > 500:
            bomb_x = random.randint(0, 500)
            bomb_y = -50
            lives -= 1
            if lives == 0:
                game_over = True

为了控制猫的坐标不超出屏幕范围，我们加入了如下的代码：

        pos_x = mouse_x
        if pos_x < 0:
            pos_x = 0
        elif pos_x > 510:
            pos_x = 500

猫在接到炸弹。或者生命值小于5的时候，会变成哭脸，因此我们还需要加载一张哭脸的位图，然后在程序中添加一些相应的逻辑代码：

#加载猫的哭脸位图
cat2=pygame.image.load("aodamiao_3.png")
#当接到炸弹的时候，猫变成哭脸
elif mine_y > pos_y:
                if mine_x > pos_x and mine_x < pos_x + 40:
                    mine_x = random.randint(0, 500)
                    mine_y = -50
                    lives-=1
                    pic=cat2
                    if lives == 0:
                        game_over = True

#当猫的生命值小于5时，猫变成哭脸
        if lives<5:
            pic=cat2

最后我们可以使用py2exe将其打包成exe并发布。py2exe打包流程请看这里：http://www.cnblogs.com/msxh/p/4886628.html

通过这个十分简陋的游戏，我们大概回顾了一下之前学到的知识。（游戏相当的简陋了，连声音都没有。。。）

下个博客我们将深入学习pygame中的Sprite（精灵）模块，并且了解如何加载动画和Sprite中的碰撞检测函数。