无法使敌人向玩家移动

Question

我正在努力让它工作。基本上，我希望我的敌人精灵追逐我的玩家精灵。目前，它斜移到屏幕的右下边缘。

我

正在学习 python 制作游戏，并且仍然是新手，所以如果这是我遇到问题的一件非常简单的事情，我深表歉意。

相关代码：

class Enemy(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.bitmap = pygame.image.load("ball.bmp")
        self.enemy_rect = self.bitmap.get_rect()
        self.enemy_rect.topleft = [100, 200]
        self.speed = 2
    def move_to_player(self, Player):
        dx, dy = self.enemy_rect.x - player.player_rect.x, self.enemy_rect.y - player.player_rect.y
        dist = math.hypot(dx, dy)
        if dist == 0:
            dist = 1
        else:
            dx, dy = dx / dist, dy / dist
        self.enemy_rect.x += dx * self.speed
        self.enemy_rect.y += dx * self.speed
while 1:  # main game loop
enemy.move_to_player(player) 

以及所有代码，用于上下文：

import pygame
import sys
import pygame.locals
import math
pygame.init() 
size = width, height = 800, 500
colour = 100, 20, 30  # colour for background
screen = pygame.display.set_mode(size)
pygame.display.set_caption('Test')
class Player(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.bitmap = pygame.image.load("ball.bmp")
        self.player_rect = self.bitmap.get_rect(
        self.player_rect.topleft = [100, 200]
    def move(self, x, y):
        self.player_rect.centerx += x
        self.player_rect.centery += y
    def render(self):
        screen.blit(self.bitmap, (self.shipRect))
class Enemy(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.bitmap = pygame.image.load("ball.bmp")
        self.enemy_rect = self.bitmap.get_rect()
        self.enemy_rect.topleft = [100, 200]
        self.speed = 2
    def move_to_player(self, Player):
        dx, dy = self.enemy_rect.x - player.player_rect.x, self.enemy_rect.y - player.player_rect.y
        dist = math.hypot(dx, dy)
        if dist == 0:
            dist = 1
        else:
            dx, dy = dx / dist, dy / dist
        self.enemy_rect.x += dx * self.speed
        self.enemy_rect.y += dx * self.speed
player = Player()
enemy = Enemy()
player.player_rect.x = 50
player.player_rect.y = 50
enemy.enemy_rect.x = 500
enemy.enemy_rect.y = 300
while 1:  # main game loop
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_DOWN:
                player.move(0, 5)
            if event.key == pygame.K_UP:
                player.move(0, -5)
            if event.key == pygame.K_LEFT:
                player.move(-5, 0)
            if event.key == pygame.K_RIGHT:
                player.move(5, 0)
        if player.player_rect.colliderect(enemy.enemy_rect):
            pygame.display.set_caption('Hit!')
    screen.fill(colour)
    screen.blit(player.bitmap, player.player_rect)
    screen.blit(enemy.bitmap, enemy.enemy_rect)
    enemy.move_to_player(player)
    pygame.display.flip()

Answer 1

首先，self.enemy_rect.y += dx * self.speed可能应该self.enemy_rect.y += dy * self.speed

其次，我认为你的数学倒退了，这样你的敌人就会逃跑。 让我们尝试一个简单的例子：

Player at 0,0; enemy at 2,0.  
Expected result if speed = 2: both at 0,0
dx = 2, dy = 0 (before normalizing by hypot)
dx = 1, dy = 0 (after)
New result: player still at 0,0; enemy at 4,0

Answer 2

这是我用来做的...

if PlayerX > AI_X:
    AI_X += 3
if PlayerX < AI_X:
    AI_X -= 3
if PlayerY > AI_Y:
    AI_Y += 3
if PlayerY < AI_Y:
    AI_Y -= 3

希望这有帮助！