问题描述
我正在开发一款游戏，该游戏涉及用户控制宇宙飞船（代码中的玩家）并射击在表面随机产生的外星人（代码中的敌人）。
截至目前，我一次只成功生成了一个外星人。我如何同时添加 6 个外星人，在子弹击中它后重生（在表面的随机位置）？
import pygame
import random
import math
# for initialising pygame (req for every pygame app)
pygame.init()
# making the basic window (dimensions must be written inside a tuple )
screen = pygame.display.set_mode((500,500))
# background
background = pygame.image.load('C:/Users/aryan/Downloads/background.jpg')
# load and set the logo
logo = pygame.image.load('C:/Users/aryan/Downloads/bp.png') # directory of logo
pygame.display.set_icon(logo)
pygame.display.set_caption("space wars") # program name
# define a variable to control the main loop
running = True
# player
playerimg = pygame.image.load('C:/Users/aryan/Downloads/spaceship.png')
playerX = 218 # x and y coordinates of image
playerY = 350
playerxchange = 0 # this will be the change in movement in x direction of our image
playerychange = 0 # this will be the change in movement in y direction of our image
def player(x,y):
screen.blit(playerimg,(x,y)) # blit draws our image on the surface(basically the background)
# Syntax for blit(imagename,(xcoordinate,ycoordinate))
# enemy
enemyimg = pygame.image.load('C:/Users/aryan/Downloads/enemy.png')
enemyX = random.randint(0,464)
enemyY = random.randint(0,30)
enemyxchange = 0.2
enemyychange = 40
# game over
overimg = pygame.image.load('C:/Users/aryan/Downloads/gameover.png')
# bullet
bulletimg = pygame.image.load('C:/Users/aryan/Downloads/bullet.png')
bulletX = 0
bulletY = 350
bulletxchange = 0
bulletychange = 1
bullet_state = "ready" # "ready" you cant see bullet on screen
# "fire" you can see bullet firing
bullets = [] # bullets is a list that contains the coordinates of every bullet
score = 0
font30 = pygame.font.SysFont(None,30)
# Functions
def enemy(x,y):
screen.blit(enemyimg,ycoordinate))
def firebullet(x,y):
global bullet_state
bullet_state = "ready"
bullets.append([x + 12,y + 6]) # Creating a new bullet
def iscollision(enemyX,enemyY,bulletX,bulletY):
distance = math.sqrt(math.pow(enemyX-bulletX,2)+ math.pow(enemyY-bulletY,2)) # distance formula
if distance <= 20:
return True
else:
return False
def Textscore(game):
text2 = font30.render("Your score is: " + str(game),True,(37,97,188))
screen.blit(text2,(10,45))
# main loop
while running:
screen.fill((120,120,120)) # in order (r,g,b) . (0,0) is black (255,0) is red...
screen.blit(background,(0,0))
# event handling,gets all event from the event queue
for event in pygame.event.get():
# only do something if the event is of type QUIT
if event.type == pygame.QUIT:
# change the value to False,to exit the main loop
running = False
# checking keystroke
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_RIGHT:
playerxchange += 0.3 # change in movement will be 0.2 towards the right
if event.key == pygame.K_LEFT:
playerxchange -= 0.3 # change in movement will be 0.2 towards the right
if event.key == pygame.K_UP:
playerychange -= 0.3
if event.key == pygame.K_DOWN:
playerychange += 0.3
if event.key == pygame.K_SPACE:
bullet_state = "fire"
firebullet(playerX,playerY)
if event.type == pygame.KEYUP:
if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT or event.key == pygame.K_DOWN or event.key == pygame.K_UP:
playerxchange = 0
playerychange = 0
playerY += playerychange
playerX += playerxchange # the value of playerx changes by +- 0.1 depending on keystroke
if playerX <= -64: # this teleports the spaceship from left end to right end
playerX = 564
elif playerX >= 564: # this teleports spaceship from right end to left
playerX = -64
if playerY >= 436: # this prevents spaceship from leaving vertically
playerY = 436
if playerY <= 0:
playerY = 0
# enemy movement
enemyX += enemyxchange
if enemyY >= 476:
enemyY = 476
enemyYchange = 0
enemyXchange = 0
if enemyX <= 0:
enemyxchange = 0.2
enemyY += enemyychange
elif enemyX >= 465:
enemyxchange = -0.2
enemyY += enemyychange
# bullet movement
if bullet_state == "fire":
firebullet(playerX,playerY)
for bullet in bullets:
screen.blit(bulletimg,(bullet[0],bullet[1])) # Print a bullet
bullet[0] -= bulletxchange # Updates its position
bullet[1] -= bulletychange
if bullet[1] < 0:
bullets.remove(bullet)
# collision
for bullet in bullets: # Use a for-loop to iterate through all the bullets in the list.
collision = iscollision(enemyX,bullet[0],bullet[1])
if collision: # Test if a single bullet collides with the enemy inside the loop.
score += 1
print(score)
bullets.remove(bullet) # Remove the bullet from the list when it collides with the enemy.
enemyX = random.randint(0,476) # if collision takes place,alien respawns
enemyY = random.randint(0,30)
Textscore(score)
player(playerX,playerY) # player method is called AFTER screen.fill otherwise the screen will fill after image has been blitted
enemy(enemyX,enemyY)
pygame.display.update() # necessary for events to keep updating
解决方法
使用 Enemy 和 move 方法创建 draw 类（请参阅 Classes）：
class Enemy:
def __init__(self):
self.x = random.randint(0,476)
self.y = 20
self.moveX = 0.2
self.moveY = 40
def move(self):
self.x += self.moveX
if self.y >= 476:
self.y = 476
self.moveY = 0
self.moveX = 0
if self.x <= 0:
self.moveX = 0.2
self.y += self.moveY
elif self.x >= 465:
self.moveX = -0.2
self.y += self.moveY
def draw(self):
screen.blit(enemyimg,(self.x,self.y))
创建多个敌人并将它们存储在列表（enemy_list ）中，而不是全局变量 enemyX、enemyY、enemyxchange 和 enemyychange：
enemyimg = pygame.image.load('C:/Users/aryan/Downloads/enemy.png')
enemy_list = []
for i in range(5):
new_enemy = Enemy()
enemy_list.append(new_enemy)
move 和 draw 循环中的敌人。对于碰撞测试，您需要检查是否有子弹击中了任何敌人。因此，碰撞测试必须在嵌套循环中进行。请注意，通过项目符号的循环必须是内循环，因为项目符号已从列表中删除：
# main loop
while running:
# [...]
for enemy in enemy_list:
enemy.move()
# [...]
# collision
for enemy in enemy_list:
for bullet in bullets: # Use a for-loop to iterate through all the bullets in the list.
collision = iscollision(enemy.x,enemy.y,bullet[0],bullet[1])
if collision: # Test if a single bullet collides with the enemy inside the loop.
score += 1
print(score)
bullets.remove(bullet) # Remove the bullet from the list when it collides with the enemy.
enemy.x = random.randint(0,476) # if collision takes place,alien respawns
enemy.y = random.randint(0,30)
# [...]
for enemy in enemy_list:
enemy.draw()
完整代码：
import pygame
import random
import math
# for initialising pygame (req for every pygame app)
pygame.init()
# making the basic window (dimensions must be written inside a tuple )
screen = pygame.display.set_mode((500,500))
# background
background = pygame.image.load('C:/Users/aryan/Downloads/background.jpg')
# load and set the logo
logo = pygame.image.load('C:/Users/aryan/Downloads/bp.png') # directory of logo
pygame.display.set_icon(logo)
pygame.display.set_caption("space wars") # program name
# define a variable to control the main loop
running = True
# player
playerimg = pygame.image.load('C:/Users/aryan/Downloads/spaceship.png')
playerX = 218 # x and y coordinates of image
playerY = 350
playerxchange = 0 # this will be the change in movement in x direction of our image
playerychange = 0 # this will be the change in movement in y direction of our image
def player(x,y):
screen.blit(playerimg,(x,y)) # blit draws our image on the surface(basically the background)
# syntax for blit(imagename,(xcoordinate,ycoordinate))
class Enemy:
def __init__(self):
self.x = random.randint(0,476)
self.y = 20
self.moveX = 0.2
self.moveY = 40
def move(self):
self.x += self.moveX
if self.y >= 476:
self.y = 476
self.moveY = 0
self.moveX = 0
if self.x <= 0:
self.moveX = 0.1
self.y += self.moveY
elif self.x >= 465:
self.moveX = -0.1
self.y += self.moveY
def draw(self):
screen.blit(enemyimg,self.y))
# enemy
enemyimg = pygame.image.load('C:/Users/aryan/Downloads/enemy.png')
enemy_list = []
for i in range(5):
new_enemy = Enemy()
enemy_list.append(new_enemy)
# game over
overimg = pygame.image.load('C:/Users/aryan/Downloads/gameover.png')
# bullet
bulletimg = pygame.image.load('C:/Users/aryan/Downloads/bullet.png')
bulletX = 0
bulletY = 350
bulletxchange = 0
bulletychange = 1
bullet_state = "ready" # "ready" you cant see bullet on screen
# "fire" you can see bullet firing
bullets = [] # bullets is a list that contains the coordinates of every bullet
score = 0
font30 = pygame.font.SysFont(None,30)
def firebullet(x,y):
global bullet_state
bullet_state = "ready"
bullets.append([x + 12,y + 6]) # Creating a new bullet
def iscollision(enemyX,enemyY,bulletX,bulletY):
distance = math.sqrt(math.pow(enemyX-bulletX,2)+ math.pow(enemyY-bulletY,2)) # distance formula
if distance <= 20:
return True
else:
return False
def TextScore(game):
text2 = font30.render("Your Score is: " + str(game),True,(37,97,188))
screen.blit(text2,(10,45))
# main loop
while running:
screen.fill((120,120,120)) # in order (r,g,b) . (0,0) is black (255,0) is red...
screen.blit(background,(0,0))
# event handling,gets all event from the event queue
for event in pygame.event.get():
# only do something if the event is of type QUIT
if event.type == pygame.QUIT:
# change the value to False,to exit the main loop
running = False
# checking keystroke
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_RIGHT:
playerxchange += 0.3 # change in movement will be 0.2 towards the right
if event.key == pygame.K_LEFT:
playerxchange -= 0.3 # change in movement will be 0.2 towards the right
if event.key == pygame.K_UP:
playerychange -= 0.3
if event.key == pygame.K_DOWN:
playerychange += 0.3
if event.key == pygame.K_SPACE:
bullet_state = "fire"
firebullet(playerX,playerY)
if event.type == pygame.KEYUP:
if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT or event.key == pygame.K_DOWN or event.key == pygame.K_UP:
playerxchange = 0
playerychange = 0
playerY += playerychange
playerX += playerxchange # the value of playerx changes by +- 0.1 depending on keystroke
if playerX <= -64: # this teleports the spaceship from left end to right end
playerX = 564
elif playerX >= 564: # this teleports spaceship from right end to left
playerX = -64
if playerY >= 436: # this prevents spaceship from leaving vertically
playerY = 436
if playerY <= 0:
playerY = 0
for enemy in enemy_list:
enemy.move()
# bullet movement
if bullet_state == "fire":
firebullet(playerX,playerY)
for bullet in bullets:
screen.blit(bulletimg,(bullet[0],bullet[1])) # Print a bullet
bullet[0] -= bulletxchange # Updates its position
bullet[1] -= bulletychange
if bullet[1] < 0:
bullets.remove(bullet)
# collision
for enemy in enemy_list:
for bullet in bullets: # Use a for-loop to iterate through all the bullets in the list.
collision = iscollision(enemy.x,30)
TextScore(score)
player(playerX,playerY) # player method is called AFTER screen.fill otherwise the screen will fill after image has been blitted
for enemy in enemy_list:
enemy.draw()
pygame.display.update() # necessary for events to keep updating
如果您想生成不重叠的敌人，请参阅以下问题的答案：