程式設計師之所以犯錯誤，不是因為他們不懂，而是因為他們自以為什麼都懂。

# The Pie Game
# Python 3.2

import math
import sys

import pygame
from pygame.locals import *
pygame.init()
screen = pygame.display.set_mode((600,500))
pygame.display.set_caption("The Pie Game - Press 1,2,3,4")
myfont = pygame.font.Font(None, 60)

color = 200, 80, 60
width = 4
x = 300
y = 250
radius = 200
position = x-radius, y-radius, radius*2, radius*2

piece1 = False
piece2 = False
piece3 = False
piece4 = False

while True:
    for event in pygame.event.get():
        if event.type == QUIT:
            sys.exit()
        elif event.type == KEYUP:
            if event.key == pygame.K_ESCAPE:
                sys.exit()
            elif event.key == pygame.K_1:
                piece1 = True
            elif event.key == pygame.K_2:
                piece2 = True
            elif event.key == pygame.K_3:
                piece3 = True
            elif event.key == pygame.K_4:
                piece4 = True
                
    #clear the screen
    screen.fill((0,0,200))
    
    #draw the four numbers
    textImg1 = myfont.render("1", True, color)
    screen.blit(textImg1, (x+radius/2-20, y-radius/2))
    textImg2 = myfont.render("2", True, color)
    screen.blit(textImg2, (x-radius/2, y-radius/2))
    textImg3 = myfont.render("3", True, color)
    screen.blit(textImg3, (x-radius/2, y+radius/2-20))
    textImg4 = myfont.render("4", True, color)
    screen.blit(textImg4, (x+radius/2-20, y+radius/2-20))


    #should the pieces be drawn?
    if piece1:
        start_angle = math.radians(0)
        end_angle = math.radians(90)
        pygame.draw.arc(screen, color, position, start_angle, end_angle, width)
        pygame.draw.line(screen, color, (x,y), (x,y-radius), width)
        pygame.draw.line(screen, color, (x,y), (x+radius,y), width)
    if piece2:
        start_angle = math.radians(90)
        end_angle = math.radians(180)
        pygame.draw.arc(screen, color, position, start_angle, end_angle, width)
        pygame.draw.line(screen, color, (x,y), (x,y-radius), width)
        pygame.draw.line(screen, color, (x,y), (x-radius,y), width)
    if piece3:
        start_angle = math.radians(180)
        end_angle = math.radians(270)
        pygame.draw.arc(screen, color, position, start_angle, end_angle, width)
        pygame.draw.line(screen, color, (x,y), (x-radius,y), width)
        pygame.draw.line(screen, color, (x,y), (x,y+radius), width)
    if piece4:
        start_angle = math.radians(270)
        end_angle = math.radians(360)
        pygame.draw.arc(screen, color, position, start_angle, end_angle, width)
        pygame.draw.line(screen, color, (x,y), (x,y+radius), width)
        pygame.draw.line(screen, color, (x,y), (x+radius,y), width)
        
    #is the pie finished?
    if piece1 and piece2 and piece3 and piece4:
        color = 0,255,0

    pygame.display.update()

 

截圖：

使用pygame實現的一個簡單的介面，按鍵盤1,2,3,4會有對應的地方亮起，當四個都亮起來之後會改變顏色

使用myfont.render畫字，再用screen.blit放到螢幕上

使用pygame.draw.arc畫弧形，使用pygame.draw.line畫線

包在while迴圈中，使用pygame.event.get()捕捉事件

最後加一個判斷，當四個都是true時改變顏色