python 每日一学（Python每日一练GameTime）

One of the great traditions of learning to program is typing in code you don’t understand. Really！（引用自《父与子的编程之旅》第十章第一句）那么我们开始吧！

Skier

输入中就发现了，作者说得真对！I,m typing in code I don’t understand！

对class和def完全无感，完全只能照着作者的程序练习打字。

但是执行后出来游戏窗口还是挺有成就感的！

接下去慢慢地把这段代码消化掉吧[流泪]

import pygame, sys, random # different images for the skier depending on his direction skier_images = ["skier_down.png", "skier_right1.png", "skier_right2.png", "skier_left2.png", "skier_left1.png"] # class for the skier sprite class SkierClass(pygame.sprite.Sprite): def __init__(self): pygame.sprite.Sprite.__init__(self) self.image = pygame.image.load("skier_down.png") self.rect = self.image.get_rect() self.rect.center = [320, 100] self.angle = 0 def turn(self, direction): # load new image and change speed when the skier turns self.angle = self.angle direction if self.angle < -2: self.angle = -2 if self.angle > 2: self.angle = 2 center = self.rect.center self.image = pygame.image.load(skier_images[self.angle]) self.rect = self.image.get_rect() self.rect.center = center speed = [self.angle, 6 - abs(self.angle) * 2] return speed def move(self, speed): # move the skier right and left self.rect.centerx = self.rect.centerx speed[0] if self.rect.centerx < 20: self.rect.centerx = 20 if self.rect.centerx > 620: self.rect.centerx = 620 # class for obstacle sprites (trees and flags) class ObstacleClass(pygame.sprite.Sprite): def __init__(self, image_file, location, type): pygame.sprite.Sprite.__init__(self) #call Sprite initializer self.image_file = image_file self.image = pygame.image.load(image_file) self.location = location self.rect = self.image.get_rect() self.rect.center = location self.type = type self.passed = False def scroll(self, terrainPos): self.rect.centery = self.location[1] - terrainPos # create one "screen" of terrain: 640 x 640 # use "blocks" of 64 x 64 pixels, so objects aren't too close together def create_map(start, end): obstacles = pygame.sprite.Group() locations = [] gates = pygame.sprite.Group() for i in range(10): # 10 obstacles per screen row = random.randint(start, end) col = random.randint(0, 9) location = [col * 64 20, row * 64 20] #center x, y for obstacle if not (location in locations): # prevent 2 obstacles in the same place locations.append(location) type = random.choice(["tree", "flag"]) if type == "tree": img = "skier_tree.png" elif type == "flag": img = "skier_flag.png" obstacle = ObstacleClass(img, location, type) obstacles.add(obstacle) return obstacles # redraw the screen, including all sprites def animate(): screen.fill([255, 255, 255]) pygame.display.update(obstacles.draw(screen)) screen.blit(skier.image, skier.rect) screen.blit(score_text, [10, 10]) pygame.display.flip() def updateObstacleGroup(map0, map1): obstacles = pygame.sprite.Group() for ob in map0: obstacles.add(ob) for ob in map1: obstacles.add(ob) return obstacles # initialize everything pygame.init() screen = pygame.display.set_mode([640,640]) clock = pygame.time.Clock() skier = SkierClass() speed = [0, 6] map_position = 0 points = 0 map0 = create_map(20, 29) map1 = create_map(10, 19) activeMap = 0 # group for all obstacles to do collision detection obstacles = updateObstacleGroup(map0, map1) # font object for score font = pygame.font.Font(None, 50) # main Pygame event loop while True: clock.tick(30) for event in pygame.event.get(): if event.type == pygame.QUIT: sys.exit() if event.type == pygame.KEYDOWN: # check for key presses if event.key == pygame.K_LEFT: # left arrow turns left speed = skier.turn(-1) elif event.key == pygame.K_RIGHT: #right arrow turns right speed = skier.turn(1) skier.move(speed) map_position = speed[1] # scroll the terrain # manage terrain maps, switch between them, # and create new terrain at the bottom if map_position >=640 and activeMap == 0: activeMap = 1 map0 = create_map(20, 29) obstacles = updateObstacleGroup(map0, map1) if map_position >=1280 and activeMap == 1: activeMap = 0 for ob in map0: ob.location[1] = ob.location[1] - 1280 # wrap around to top map_position = map_position - 1280 # map1 = create_map(10, 19) obstacles = updateObstacleGroup(map0, map1) for obstacle in obstacles: obstacle.scroll(map_position) # check for hitting trees or getting flags hit = pygame.sprite.spritecollide(skier, obstacles, False) if hit: if hit[0].type == "tree" and not hit[0].passed: #crashed into tree points = points - 100 skier.image = pygame.image.load("skier_crash.png") # crash image animate() pygame.time.delay(1000) skier.image = pygame.image.load("skier_down.png") # resume skiing skier.angle = 0 speed = [0, 6] hit[0].passed = True elif hit[0].type == "flag" and not hit[0].passed: # got a flag points = 10 obstacles.remove(hit[0]) # remove the flag score_text = font.render("Score: " str(points), 1, (0, 0, 0)) animate()