glShadeModel(GL_SMOOTH) glEnable(GL_POINT_SMOOTH) glEnable(GL_LINE_SMOOTH)
glEnable(GL_POLYGON_SMOOTH) glMatrixMode(GL_PROJECTION)
glHint(GL_POINT_SMOOTH_HINT,GL_NICEST) glHint(GL_LINE_SMOOTH_HINT,GL_NICEST)
glHint(GL_POLYGON_SMOOTH_HINT,GL_FASTEST) glLoadIdentity()
gluPerspective(45.0, float(width)/float(height), 0.1, 100.0) glMatrixMode(GL_MODELVIEW) def MainLoop(self): glutMainLoop()
if __name__ == '__main__': w = MyPyOpenGLTest() w.MainLoop()
15.2 编写程序，读取两幅大小一样的图片，然后将两幅图像的内容叠加到一幅图像，结果图像中每个像素值为原两幅图像对应位置像素值的平均值。
答：
from PIL import Image
im1 = Image.open('d:\\\\pic1.bmp') im2 = Image.open('d:\\\\pic2.bmp') size = im1.size
for i in range(size[0]): for j in range(size[1]):
color1 = im1.getpixel((i,j)) color2 = im2.getpixel((i,j)) r = (color1[0]+color2[0])//2 g = (color1[1]+color2[1])//2 b = (color1[2]+color2[2])//2 im1.putpixel((i,j),(r,g,b))
im1.save('d:\\\\pic3.bmp') im1.close() im2.close()
15.3 编写程序，读取一幅图像的内容，将其按象限分为4等份，然后1、3象限内容交换，2、4象限内容交换，生成一幅新图像。
答：
from PIL import Image
im = Image.open('d:\\\\pic1.bmp') im2 = Image.open('d:\\\\pic1.bmp') size = im.size
box1 = (0, size[1]/2, size[0]/2, size[1]) region1 = im.crop(box1)
box2 = (0, 0, size[0]/2, size[1]/2) region2 = im.crop(box2)
box3 = (size[0]/2, 0, size[0], size[1]/2) region3 = im.crop(box3)
box4 = (size[0]/2, size[1]/2, size[0], size[1]) region4 = im.crop(box4)
im2.paste(region1, box3) im2.paste(region3, box1) im2.paste(region2, box4) im2.paste(region4, box2)
im2.save('d:\\\\pic4.bmp') im.close() im2.close()
15.4 结合GUI编程知识，编写一个程序，创建一个窗口并在上面放置两个按钮，分别为“开始播放”和“暂停播放”，将本章15.3节中的音乐播放程序进行封装。
答：
import wx import os
import pygame import random import time import threading
class wxGUI(wx.App): def OnInit(self):
frame = wx.Frame(parent=None, title='MP3Player', size=(250,150), pos=(350,350)) panel = wx.Panel(frame, -1)
self.buttonOK = wx.Button(panel, -1, 'Play', pos=(30,60))
self.Bind(wx.EVT_BUTTON, self.OnButtonOK, self.buttonOK)
self.buttonOK.Enabled = True
self.buttonCancel = wx.Button(panel, -1, 'Stop', pos=(120,60))
self.Bind(wx.EVT_BUTTON, self.OnButtonCancel, self.buttonCancel) self.buttonCancel.Enabled = False
frame.Show() return True def OnExit(self): try:
self.playing = False
pygame.mixer.music.stop() finally: pass
def play(self):
folder = r'h:\\music'
musics = [folder+'\\\\'+music for music in os.listdir(folder) if music.endswith('.mp3')] total = len(musics) pygame.mixer.init() while self.playing:
if not pygame.mixer.music.get_busy(): nextMusic = random.choice(musics) pygame.mixer.music.load(nextMusic) pygame.mixer.music.play(1) print 'playing....',nextMusic else:
time.sleep(1)
def OnButtonOK(self, event): self.playing = True
# create a new thread to play music t = threading.Thread(target=self.play) t.start()
self.buttonOK.Enabled = False
self.buttonCancel.Enabled = True
def OnButtonCancel(self, event): self.playing = False
pygame.mixer.music.stop() self.buttonOK.Enabled = True self.buttonCancel.Enabled = False
app = wxGUI()
app.MainLoop()
15.5 运行本章15.4中的代码并查看运行结果。 答：略。