增加游戏的可玩性
上一节的游戏太过单调了，我们继续给游戏增加一些可玩性内容。
- • 显示分数
- • 游戏的进入界面和结算界面
- • 让敌人的逻辑不那么单调
- • 让角色的动作更生动
显示分数
这里我们将分数设置为玩家坚持的时间，每过一秒，分数 1。具体实现用到了pygame.time.get_ticks()获取时间。
相关代码：
代码语言：javascript复制def display_score():
current = pygame.time.get_ticks() // 1000 - start_time
score_surf = test_font.render(f"Score:{current}", False, (64,64,64))
screen.blit(score_surf,score_surf.get_rect(center=(400,50)))
return current进入界面和结算界面
在游戏开始时，提示玩家玩法。在游戏结束时，进入结算界面，显示玩家得分。为了实现上述目的，我们需要设置一个全局变量game_activate来记录游戏状态。并且在游戏主循环中，（使用if~else）根据状态进行不同的显示。
相关代码：
代码语言：javascript复制game_activate = False
while True:
...
if game_activate :
# 正常游戏
...
else:
# 显示游戏结束界面
...让敌人的逻辑不那么单调
只是一只蜗牛重复地跑，未免太单调了。我们创建一个列表，存放多个敌人。显示和碰撞检测也对列表进行操作。并且利用 random.randint()给敌人的种类和位置增加随机性。
相关代码：
代码语言：javascript复制obstacle_rect_list = []
def collisions(player , obstacles):
if obstacles:
for obstacle_rect in obstacles:
if player.colliderect(obstacle_rect):
return True
return False此外，为了定时生成敌人，用到了定时器Timer，其作用是每间隔一定时间，就生成一个pygame.event。
代码语言：javascript复制# Timer
obstacle_timer = pygame.USEREVENT 1
pygame.time.set_timer(obstacle_timer, 1500)
for event in pygame.event.get():
if game_activate:
...
if event.type == obstacle_timer:
if random.randint(0,2):
obstacle_rect_list.append(snail_surf.get_rect(bottomright=(random.randint(900, 1100), 300)))
...让角色的动作更生动
通过两种图片的快速切换，可以制造出动画的效果：
利用这个原理，让人物的腿跑起来：
player_walk_1 = pygame.image.load('graphics/Player/player_walk_1.png').convert_alpha()
player_walk_2 = pygame.image.load('graphics/Player/player_walk_2.png').convert_alpha()
player_walk = [player_walk_1, player_walk_2]
player_index = 0
player_jump = pygame.image.load('graphics/Player/jump.png').convert_alpha()
player_surf = player_walk[player_index]
player_rect = player_surf.get_rect(midbottom=(80, 300))
def player_animation():
global player_surf, player_index
if player_rect.bottom <300:
# jump
player_surf = player_jump
else:
player_index = 0.1 # 我们不想腿变换的频率太快
if player_index >= len(player_walk): player_index = 0
player_surf = player_walk[int(player_index)]
对于蜗牛和苍蝇，我们使用timer 来更新动画。每次timer触发，所有的蜗牛和苍蝇都会更新。（蜗牛和苍蝇有各自的timer）。(为什么这里要用timer呢？为蜗牛和苍蝇分别设置各自的timer，方便我们分别控制蜗牛和苍蝇动画更新的频率。如果你乐意，也可以把人物动画用timer实现)
代码语言：javascript复制snail_animation_timer = pygame.USEREVENT 2
pygame.time.set_timer(snail_animation_timer,800)
fly_animation_timer = pygame.USEREVENT 3
pygame.time.set_timer(fly_animation_timer,200)
# 获取用户输入
for event in pygame.event.get():
if event.type == snail_animation_timer:
snail_frames_index = ~snail_frames_index
snail_surf = snail_frames[snail_frames_index]
if event.type == fly_animation_timer:
fly_frames_index = ~fly_frames_index
fly_surf = fly_frames[fly_frames_index]
最终效果：
完整代码：
代码语言：javascript复制import random
import pygame
from sys import exit
def display_score():
# 显示分数
current = pygame.time.get_ticks() // 1000 - start_time
score_surf = test_font.render(f"Score:{current}", False, (64, 64, 64))
screen.blit(score_surf, score_surf.get_rect(center=(400, 50)))
return current
def player_animation():
# 播放主角跑步和跳跃的动画
global player_surf, player_index
if player_rect.bottom < 300:
# jump
player_surf = player_jump
else:
player_index = 0.1 # 我们不想腿变换的频率太快
if player_index >= len(player_walk): player_index = 0
player_surf = player_walk[int(player_index)]
# 初始化 引擎
pygame.init()
# 设置屏幕
screen = pygame.display.set_mode((800, 400)) # 宽度800，高度400
pygame.display.set_caption('Runner') # 设置标题
# 时钟
clock = pygame.time.Clock()
# 字体
test_font = pygame.font.Font('font/Pixeltype.ttf', 50)
# 背景
sky_surf = pygame.image.load('graphics/Sky.png').convert()
ground_surf = pygame.image.load('graphics/ground.png').convert()
# 得分
score_surf = test_font.render("My game", False, 'Black')
score_rect = score_surf.get_rect(center=(400, 50))
# 游戏简介
game_name_surf = test_font.render("Runner", False, 'Black')
game_name_rect = game_name_surf.get_rect(center=(400, 80))
game_message_surf = test_font.render("Press space to run", False, (111, 196, 169))
game_message_rect = game_message_surf.get_rect(center=(400, 320))
# Obstacles （障碍，有蜗牛和苍蝇）
snail_frame_1 = pygame.image.load('graphics/snail/snail1.png').convert_alpha()
snail_frame_2 = pygame.image.load('graphics/snail/snail2.png').convert_alpha()
snail_frames = [snail_frame_1, snail_frame_2]
snail_frames_index = 0
snail_surf = snail_frames[snail_frames_index]
fly_frame_1 = pygame.image.load('graphics/Fly/Fly1.png').convert_alpha()
fly_frame_2 = pygame.image.load('graphics/Fly/Fly2.png').convert_alpha()
fly_frames = [fly_frame_1, fly_frame_2]
fly_frames_index = 0
fly_surf = fly_frames[fly_frames_index]
obstacle_rect_list = []
# 人物
player_walk_1 = pygame.image.load('graphics/Player/player_walk_1.png').convert_alpha()
player_walk_2 = pygame.image.load('graphics/Player/player_walk_2.png').convert_alpha()
player_walk = [player_walk_1, player_walk_2]
player_index = 0
player_jump = pygame.image.load('graphics/Player/jump.png').convert_alpha()
player_surf = player_walk[player_index]
player_rect = player_surf.get_rect(midbottom=(80, 300))
player_stand_surf = pygame.image.load('graphics/Player/player_stand.png').convert_alpha()
player_stand_surf = pygame.transform.rotozoom(player_stand_surf, 0, 2)
player_stand_rect = player_stand_surf.get_rect(midbottom=(400, 300))
player_gravity = 0
game_activate = False
start_time = 0
score = 0
# Timer
obstacle_timer = pygame.USEREVENT 1
pygame.time.set_timer(obstacle_timer, 1500)
snail_animation_timer = pygame.USEREVENT 2
pygame.time.set_timer(snail_animation_timer, 800)
fly_animation_timer = pygame.USEREVENT 3
pygame.time.set_timer(fly_animation_timer, 200)
def obstacle_movement(obstacle_rect_list):
# 移动障碍
if obstacle_rect_list:
for obstacle_rect in obstacle_rect_list:
obstacle_rect.x -= 5
if obstacle_rect.bottom == 300:
screen.blit(snail_surf, obstacle_rect)
else:
screen.blit(fly_surf, obstacle_rect)
obstacle_rect_list = [obstacle_rect for obstacle_rect in obstacle_rect_list if obstacle_rect.x > 0]
else:
obstacle_rect_list = []
return obstacle_rect_list
def collisions(player, obstacles):
# 碰撞检测
if obstacles:
for obstacle_rect in obstacles:
if player.colliderect(obstacle_rect):
return True
return False
while True:
# 获取用户输入
for event in pygame.event.get():
# 用户点击退出，关闭游戏
if event.type == pygame.QUIT:
pygame.quit()
exit()
if game_activate:
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE and player_rect.bottom >= 300:
player_gravity -= 20
if event.type == obstacle_timer:
if random.randint(0, 2):
obstacle_rect_list.append(snail_surf.get_rect(bottomright=(random.randint(900, 1100), 300)))
else:
obstacle_rect_list.append(fly_surf.get_rect(bottomright=(random.randint(900, 1100), 210)))
if event.type == snail_animation_timer:
snail_frames_index = ~snail_frames_index
snail_surf = snail_frames[snail_frames_index]
if event.type == fly_animation_timer:
fly_frames_index = ~fly_frames_index
fly_surf = fly_frames[fly_frames_index]
else:
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE:
game_activate = True
start_time = pygame.time.get_ticks() // 1000
# 游戏运行：绘图,更新
if game_activate:
pygame.draw.rect(screen, '#c0e8ec', score_rect)
pygame.draw.rect(screen, '#c0e8ec', score_rect, 10)
screen.blit(sky_surf, (0, 0)) # 将test_surface放到screen上。(0,0)：放置后test_surface的左上角位于screen的(0,0)处
screen.blit(ground_surf, (0, 300))
score = display_score()
obstacle_rect_list = obstacle_movement(obstacle_rect_list)
player_gravity = 1
player_rect.y = player_gravity
if player_rect.bottom >= 300:
player_rect.bottom = 300
player_gravity = 0
player_animation()
screen.blit(player_surf, player_rect)
if collisions(player_rect, obstacle_rect_list):
game_activate = False
# 游戏结束：
else:
obstacle_rect_list.clear()
player_rect.midbottom = (80, 300)
player_gravity = 0
screen.fill((94, 129, 162))
screen.blit(player_stand_surf, player_stand_rect)
screen.blit(game_name_surf, game_name_rect)
if score == 0:
screen.blit(game_message_surf, game_message_rect)
else:
score_message = test_font.render(f'Your score:{score}', False, (111, 196, 169))
score_message_rect = score_message.get_rect(center=(400, 320))
screen.blit(score_message, score_message_rect)
pygame.display.update()
clock.tick(60) # 不超过60 fps
