如何在不同方向随机生成子弹

Question

我一直在尝试编写一个火鸡必须躲避子弹的游戏，这是一个2d游戏，所以它只能向上、向下、向左和向右移动。我试着加入游戏的逻辑"；小行星"；小行星随机产卵，但仍然没有运气。

import pygame
bakcground = pygame.image.load("Bulletspix/Grass BG.png")
PlayerTurk = pygame.image.load ("Bulletspix/turkey.png")
playerTurkx = 450
playerTurky = 800
vel = 1
pygame.display.set_caption("game")
screen = pygame.display.set_mode((800, 900))
playerTurkx = 350
playerTurky = 350
vel = 1
def player():
screen.blit(PlayerTurk, (playerTurkx , playerTurky))
running = True
while running:
#Oprion of quitting
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
# Background
screen.fill((0, 0, 0))
screen.blit(bakcground, (0, 0))
#movement
Input = pygame.key.get_pressed()
if Input[pygame.K_LEFT] and playerTurkx >0:
playerTurkx -= vel
if Input[pygame.K_RIGHT]and playerTurkx <730:
playerTurkx += vel
if Input[pygame.K_UP]and playerTurky >0:
playerTurky -= vel
if Input[pygame.K_DOWN]and playerTurky <500:
playerTurky += vel
player()
pygame.display.update()
pygame.quit()

Answer 1

首先，创建一个列表来存储项目符号。

bullets = []
# And some other necessary variables.
seconds_since_spawn = 0.0
player_lives = 3
BULLET_START_POSITION = (799, 449)

然后，在循环中的每一次迭代中：

1. 每N次迭代/秒，在固定位置生成一个子弹(稍后随机化(。

   if seconds_since_spawn >= 1.0:
   seconds_since_spawn = 0.0
   bullets.append(BULLET_START_POSITION)
   

2. 将所有项目符号在屏幕上移动一步。

   bullets = [(x - 1, y) for x, y in bullets]
   

3. 检查是否有子弹与玩家相撞。

   def collided_with_player(x, y):
   return check_collision(
   player.x, player.y, PLAYER_RADIUS, x, y, BULLET_RADIUS
   )
   player_lives -= sum(
   1 for x, y in bullets if collided_with_player(x, y)
   )
   if player_lives <= 0:
   running = False  # end game
   

4. 从列表中删除所有在屏幕上看不到的项目符号，或与播放器碰撞的项目符号。

   bullets = [
   (x, y)
   for x, y in bullets
   if is_inside_screen(x, y) and not collided_with_player(x, y)
   ]
   

5. 绘制所有项目符号。

   for x, y in bullets:
   draw_bullet(x, y)