为什么添加 def 时语法无效？

Question

import pygame
import math

#initialise pygame
pygame.init()

#game window
WINDOW_WIDTH = 1200
WINDOW_HEIGHT = 750

#create game window
win = pygame.display.set_mode((WINDOW_WIDTH, WINDOW_HEIGHT))
pygame.display.set_caption('Castle Defender')

clock = pygame.time.Clock()
FPS = 60


#load images
background_img = pygame.image.load('Animations/BG.png').convert_alpha()
background = pygame.transform.scale(background_img,(1200,750))

castle_img = pygame.image.load('Animations/Castle.png').convert_alpha()

bullet_img = pygame.image.load('Animations/SmallBullet.png').convert_alpha()
b_w = bullet_img.get_width()
b_h = bullet_img.get_height()
bullet_img = pygame.transform.scale(bullet_img, (int(b_w * 0.075), int(b_h * 0.075)))

WHITE =(255,255,255)



            
#Castle class
class Castle():
    def __init__(self, image, x, y, scale):
        self.health = 1000
        self.max_health = self.health

        width = image.get_width()
        height = image.get_height()

        self.image = pygame.transform.scale(image, (int(width * scale), int(height * scale)))
        self.rect = self.image.get_rect()
        self.rect.x = x
        self.rect.y = y

    def shoot(self):
        pos = pygame.mouse.get_pos()
        x_dist = pos[0] - self.rect.midleft[0]
        y_dist = -(pos[1] - self.rect.midleft[1])
        self.angle = math.degrees(math.atan2(y_dist, x_dist))
        #mouseclick
        if pygame.mouse.get_pressed()[0] and self.fired == False:
            self.fired = True
            bullet = Bullet(bullet_img, self.rect.right[0], self.rect.right[1], self.angle)
            bullet_group.add(bullet)
        #reset mouseclick
        if pygame.mouse.get_pressed()[0] == False:
            self.fired = False
                         
#Method
    def draw(self):
        self.image = self.image

        win.blit(self.image, self.rect)

class Bullet(pygame.sprite.Sprite):
    def __init__(self, image, x, y, angle):
        pygame.sprite.Sprite.__init__(self)
        self.image = image
        self.rect = self.image.get_rect()
        self.rect.x = x
        self.rect.y = y
        self.angle = math.radians(angle)
        self.speed = 10
        self.dx = math.cos(self.angle) * self.speed
        self.dy = -(math.sin(self.angle) * self.speed)

    def update(self):
        #check if bullet has gone off the screen
        if self.rect.right < 0 or self.rect.left > SCREEN_WIDTH or self.rect.bottom < 0 or self.rect.top > SCREEN_HEIGHT:
            self.kill()         

        #move bullet
        self.rect.x += self.dx
        self.rect.y += self.dy


castle = Castle(castle_img, WINDOW_WIDTH - 1350, WINDOW_HEIGHT - 400, 0.7)


bullet_group = pygame.sprite.Group()


run = True
while run:

    clock.tick(FPS)

    win.blit(background, (0, 0))
    
    castle.draw()
    castle.shoot()

    #bullet drawing
    bullet_group.update()
    bullet_group.draw(win)
    print(len(bullet_group))

    
    #event handler
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

    #update display window
    pygame.display.update()

pygame.quit()

I am trying to see the line from my base and my mouse. However I get an error of the following

bullet = Bullet(bullet_img, self.rect.right[0], self.rect.right[1], self.angle)

(My end goal is for bullets to come out of the castle and i am relatively new to coding and this will be my first project). Also i keep getting an error when trying to submit this saying it is mostly code so the parenthisis was me rambling on

Answer 1

The issue the code is trying to use self.rect.right as if it was a python list. But self.rect.right is an integer.

self.rect.right[0]
self.rect.right[1]

Probably this should be self.rect.right and self.rect.top (since it deals with the y -dimension).

Then you also need to correct references to SCREEN_WIDTH and SCREEN_HEIGHT . It looks like these should be WINDOW_ etc.

After these changes are made, your program does not exit with an error when the mouse is clicked.