Python中的画图初体验-白红宇

学到《父与子编程之旅》的16章了，跟书上的例子进行学习，学会了画圆，我又找到了画线的方法，于是就可以在screen上画日本国旗了：

手动画的不好看，也可以不手动画，直接画线：

当然也可以直接画个矩形套在外面：

代码如下：

1 import pygame,sys   2 from pygame.locals import *  3 print pygame.ver 4 pygame.init() 5 screen = pygame.display.set_mode([640,480]) 6 color=(200,156,64)   7 points=[]  8 screen.fill([255,255,255]) 9 pygame.draw.circle(screen,[255,0,0],[200,200],70,0)10 ##pygame.draw.line(screen,color,(20,20),(400,20),1)11 ##pygame.draw.line(screen,color,(20,20),(20,400),1)12 ##pygame.draw.line(screen,color,(20,400),(400,400),1)13 ##pygame.draw.line(screen,color,(400,400),(400,20),1)14 pygame.draw.rect(screen,[255,0,0],[20,20,380,380],1)15 pygame.display.flip()16 running = True17 while running:18     for event in pygame.event.get():19         if event.type == pygame.QUIT:20             running = False21 ##        if event.type==MOUSEBUTTONDOWN:  22 ##            points.append(event.pos)23 ##    if len(points)>1:  24 ##        pygame.draw.lines(screen,color, False, points, 5)25 ##    pygame.display.update()  26 pygame.quit()

下面画一个“艺术品”，100个随机颜色随机大小的矩形，这也是书上的例子，不过让我改了一种写法，熟悉一下Python：

1 import pygame,sys,random 2 from pygame.color import THECOLORS 3 class draw: 4     def drawThePic(self): 5         pygame.init() 6         screen = pygame.display.set_mode([640,480]) 7         screen.fill([255,255,255])    8         for i in range(100): 9             forRect = []10             for j in range(4):11                     forRect.append(random.randint(0,250))12             pygame.draw.rect(screen,self.chooseColor(),forRect,2)13         pygame.display.flip()14         running = True15         while running:16             for event in pygame.event.get():17                 if event.type == pygame.QUIT:18                     running = False19         pygame.quit()20     def chooseColor(self):21         color_name = random.choice(THECOLORS.keys())22         color = THECOLORS[color_name]23         return color24 drawer = draw()25 drawer.drawThePic()

上面这段程序需要注意一下，刚接触Python，调试中总会出现问题，比如改变列表中的变量的值的时候并不改变列表的值，还有方法定义的时候一定要在括号里加上self，还有调用的时候也要在前面加上self或者其他类的名字。

接下来，画一个正弦曲线：

以上是通过一个又一个小矩形拼成的不连续的正弦曲线，也可以画一个连续的正弦曲线，如下：

代码如下（##后面是之前画“艺术品”时的代码，#后面是不连续正弦曲线的代码）：

1 import pygame,sys,random 2 from pygame.color import THECOLORS 3 import math 4 class draw: 5     def drawThePic(self): 6         pygame.init() 7         screen = pygame.display.set_mode([640,480]) 8         screen.fill([255,255,255]) 9         plotPoints = []10         for x in range(0,640):11             y = int(math.sin(x/640.0 * 4 * math.pi) * 200 +240)12             plotPoints.append([x,y])13 #            forRect = [x,y,2,2]14 ##            for j in range(4):15 ##                    forRect.append(random.randint(0,500))16 #            pygame.draw.rect(screen,self.chooseColor(),forRect,2)17         pygame.draw.lines(screen,self.chooseColor(),False,plotPoints,1)18         pygame.display.flip()19         running = True20         while running:21             for event in pygame.event.get():22                 if event.type == pygame.QUIT:23                     running = False24         pygame.quit()25     def chooseColor(self):26         color_name = random.choice(THECOLORS.keys())27         color = THECOLORS[color_name]28         return color29 drawer = draw()30 drawer.drawThePic()

至此，我已经学会了画线，画正弦曲线，画圆，画矩形，um……附上一个“艺术品”的图片：

接下来，我们来做些背景图片：

代码如下：

1 import pygame, sys 2 class ImageRun: 3     def letImageRun(self): 4         pygame.init() 5         screen = pygame.display.set_mode([640,480]) 6         screen.fill([255,255,255]) 7         background = pygame.image.load("C:/Users/dswu/Desktop/back.jpg") 8         screen.blit(background,(0,0)) 9         my_image = pygame.image.load("C:/Users/dswu/Desktop/fuck16.jpg")10         screen.blit(my_image, [50,50])11         pygame.display.flip()12         running = True13         while running:14             for event in pygame.event.get():15                 if event.type ==pygame.QUIT:16                     running = False17         pygame.quit()          18 runImage = ImageRun()19 runImage.letImageRun()

在此基础上我们就可以做个小动画了，让图片动起来：

以下代码能够让妙蛙种子左右来回运动（碰壁就反弹）：

1 import pygame, sys 2 class ImageRun: 3     def letImageRun(self): 4         pygame.init() 5         screen = pygame.display.set_mode([640,480]) 6         screen.fill([255,255,255]) 7         background = pygame.image.load("C:/Users/dswu/Desktop/back.png") 8         screen.blit(background,(0,0)) 9         my_image = pygame.image.load("C:/Users/dswu/Desktop/player.png")10         x = 40011         y = 5012         x_speed = 513         screen.blit(my_image, [x,y])14         pygame.display.flip()15         running = True16         while running:17             for event in pygame.event.get():18                 if event.type ==pygame.QUIT:19                     running = False20             #Let the image run.21             for looper in range(1,100):    22                 pygame.time.delay(20)23                 background = pygame.image.load("C:/Users/dswu/Desktop/back.png")24                 screen.blit(background,(0,0))25                 pygame.display.flip()26                 pygame.time.delay(1)27                 x = x + x_speed28                 if x < 0 or x > screen.get_width() - my_image.get_width():29                     x_speed = - x_speed30                 screen.blit(my_image,[x,y])             31                 pygame.display.flip()32         pygame.quit()          33 runImage = ImageRun()34 runImage.letImageRun()

接下来……