Pygame - 让敌人的精灵向玩家移动

Question

截至目前，敌人精灵只是在轴上产生，并与玩家一起“移动”，这实际上是一个滚动背景，我希望敌人只沿 X 轴移动，这样它就不会破坏沉浸感。

我还想让精灵产生“离开地图”，每当地图向它们滚动时，它们就会向玩家设置的 X 轴移动？ 我认为这会让事情变得简单，但现在并不是真正的问题。

我试图为运动工作的当前代码是：

def move_towards_player(self, player):
        # Find direction vector (dx, dy) between enemy and player.
        dx, dy = player.rect.x - self.rect.x, player.rect.y - self.rect.y
        dist = math.hypot (dx, dy)
        dx, dy = dx / dist, dy / dist # Normalize
        # Move along this normalized vector towards the player
        self.rect.x += dx * self.speed
        self.rect.y += dy * self.speed

但它不起作用，这是导入数学模块。 （我知道我不需要 y 动作只是想让它先工作）

这是其余的代码——

僵尸.py：

import pygame
from pygame.locals import *
import random
import math

class ZombieEnemy(pygame.sprite.Sprite):
    def __init__(self, x=300, y=360):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.image.load('images/zombie.png')
        self.rect = self.image.get_rect()
        self.rect.center = (x, y)

all_zombies = pygame.sprite.Group()


for i in range( 50 ):
    new_x = random.randrange( 0, 10000)       # random x-position
    # new_y = random.randrange( 0, )      # random y-position
    all_zombies.add(ZombieEnemy(new_x))         # create, and add to group

我不确定我是否应该为敌人的运动创建一个全新的类，或者我的伙伴目前在播放器上工作，并让精灵动画和运动正常工作。

但这是我目前的主要代码：

import pygame
from Zombie import *
import math
from pygame.locals import *
pygame.init()
​
win = pygame.display.set_mode((900,567))
​
pygame.display.set_caption("Power Rangers ZOMBIES")
​
walkRight = [pygame.image.load('images/walk1.png'), pygame.image.load('images/walk2.png'), pygame.image.load('images/walk3.png'), pygame.image.load('images/walk4.png'), pygame.image.load('images/walk5.png'), pygame.image.load('images/walk6.png')]
walkLeft = [pygame.image.load('images/leftwalk2.png'), pygame.image.load('images/leftwalk3.png'), pygame.image.load('images/leftwalk4.png'), pygame.image.load('images/leftwalk5.png'), pygame.image.load('images/leftwalk6.png'), pygame.image.load('images/leftwalk7.png')]
bg = pygame.image.load('images/background.png')
char = pygame.image.load('images/standingstill.png')
clock = pygame.time.Clock()
​
class Player(pygame.sprite.Sprite):
    def __init__(self,x,y,width,height):
        self.x = x
        self.y = y
        self.width = width
        self.height = height
        self.vel = 0
        self.isJump = False
        self.left = False
        self.right = False
        self.walkCount = 0
        self.jumpCount = 10
​
    def draw(self, win):
        if self.walkCount + 1 >= 18:
            self.walkCount = 0
​
        if self.left:
            win.blit(walkLeft[self.walkCount//3], (self.x,self.y))
            self.walkCount += 1
        elif self.right:
            win.blit(walkRight[self.walkCount//3], (self.x,self.y))
            self.walkCount +=1
        else:
            win.blit(char, (self.x,self.y))
​
class Background(pygame.sprite.Sprite):
    def __init__(self, image_file, location):
        pygame.sprite.Sprite.__init__(self)  #call Sprite initializer
        self.image = pygame.image.load('images/background.png')
        self.rect = self.image.get_rect()
        self.rect.left, self.rect.top = location
​
BackGround = Background('images/background.png', [0,0])
​
# def redrawGameWindow():
#     win.blit(bg, (0,0))
#     man.draw(win)

#     pygame.display.update()
​
#mainloop
man = Player(100, 340, 40, 60)
run = True
while run:
    clock.tick(27)
​
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False
​
    keys = pygame.key.get_pressed()
​
    if keys[pygame.K_LEFT] and man.x > man.vel:
        BackGround.rect.left = BackGround.rect.left + int(10)
        man.x -= man.vel
        man.left = True
        man.right = False
    elif keys[pygame.K_RIGHT]: #and man.x < 500 - man.width - man.vel:
        BackGround.rect.left = BackGround.rect.left - int(10)
        man.x += man.vel
        man.right = True
        man.left = False
    else:
        man.right = False
        man.left = False
        man.walkCount = 0

    if not(man.isJump):
        if keys[pygame.K_SPACE]:
            man.isJump = True
            man.right = False
            man.left = False
            man.walkCount = 0
    else:
        if man.jumpCount >= -10:
            neg = 1
            if man.jumpCount < 0:
                neg = -1
            man.y -= (man.jumpCount ** 2) * 0.5 * neg
            man.jumpCount -= 1
        else:
            man.isJump = False
            man.jumpCount = 10

    # redrawGameWindow()
    for zombie in all_zombies:
        zombie.move_towards_player(Player)
    all_zombie.update()
    win.blit(BackGround.image, BackGround.rect)
    man.draw(win)
    pygame.display.flip()
    all_zombies.draw(screen)
​
pygame.quit()

Answer 1

我无法运行代码，但我看到两个问题

1 - move_towards_player必须在类ZombieEnemy

# --- classes ---

class ZombieEnemy(pygame.sprite.Sprite):

    def __init__(self, x=300, y=360):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.image.load('images/zombie.png')
        self.rect = self.image.get_rect()
        self.rect.center = (x, y)

    def move_towards_player(self, player):
        # Find direction vector (dx, dy) between enemy and player.
        dx, dy = player.rect.x - self.rect.x, player.rect.y - self.rect.y
        dist = math.hypot (dx, dy)
        dx, dy = dx / dist, dy / dist # Normalize
        # Move along this normalized vector towards the player
        self.rect.x += dx * self.speed
        self.rect.y += dy * self.speed 

 # --- other ---

 all_zombies = pygame.sprite.Group()

2 - 你必须在主循环中使用它

    for zombie in all_zombies:
        zombie.move_towards_player(player)

在主循环中

while running:

    # --- events ---

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
    # If keystroke is pressed check right, left.
    if event.type == pygame.KEYDOWN:
        if event.key == pygame.K_LEFT:
            #playerX_change = -2.0
            BackGround.rect.left = BackGround.rect.left + 2.5
        if event.key == pygame.K_RIGHT:
            #playerX_change = 2.0
            BackGround.rect.left = BackGround.rect.left - 2.5
    # if event.type == pygame.KEYUP:
    #     if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT:
    #         BackGround.rect.left = 0

    # --- updates/moves ---

    playerX += playerX_change

    for zombie in all_zombies:
        zombie.move_towards_player(player)
    all_zombies.update()

    # --- draws ---

    screen.blit(BackGround.image, BackGround.rect)
    player(playerX,playerY)
    all_zombies.draw(screen)
    pygame.display.flip()

但是在这里我看到了其他问题 - 您的函数期望 player 作为内部带有self.rect类实例（类似于ZombieEnemy ）但您将player作为单独的变量playerImg 、 playerX 、 playerY 、 playerX_change

所以，你必须创建一流的Player ，或者你必须使用playerx, playery在move_towards_player代替player.rect.x ， player.rect.y