如何更改太空入侵者计划中的图像？

Posted 2023-03-22

【中文标题】如何更改太空入侵者计划中的图像？

【英文标题】：How to Change Images in Space Invaders Program?

【发布时间】：2022-01-15 09:53:55

【问题描述】：

语言：Python

不久前，我关注了一个关于太空入侵者的教程，比如来自 youtube 的游戏，并希望将代码重用于我正在做的项目并只是更改图像，但是当我去更改图像时，代码没有处理错误：

Traceback (most recent call last):
  File "/Users/carolinerongen/Desktop/ListGames/ListGame.py", line 277, in <module>
    main_menu()
  File "/Users/carolinerongen/Desktop/ListGames/ListGame.py", line 273, in main_menu
    main()
  File "/Users/carolinerongen/Desktop/ListGames/ListGame.py", line 207, in main
    enemy = Enemy(random.randrange(50, WIDTH-100), random.randrange(-1500, -100), random.choice(["llama1", "llama2", "llama3"]))
  File "/Users/carolinerongen/Desktop/ListGames/ListGame.py", line 133, in __init__
    self.ship_img, self.laser_img = self.COLOR_MAP[color]
KeyError: 'llama1'
>>> 

当我运行代码时会显示背景图像，但我放置的所有其他新图像都不起作用或显示。我如何让他们出现/我做错了什么？

这是我的代码：

import pygame
import pygame as pg
import os
import time
import random

pg.font.init()

WIDTH, HEIGHT = 750, 750
WIN = pg.display.set_mode((WIDTH, HEIGHT))
pg.display.set_caption("Llamas!")

llama1 = pg.image.load(os.path.join("assets", "llama.png"))
llama2 = pg.image.load(os.path.join("assets", "llama.png"))
llama3 = pg.image.load(os.path.join("assets", "llama.png"))
llama4 = pg.image.load(os.path.join("assets", "llama.png"))


playerss = pg.image.load(os.path.join("assets", "pixel_ship_yellow.png"))
playerl = pg.image.load(os.path.join("assets", "pixel_laser_yellow.png"))

redl = pg.image.load(os.path.join("assets", "pixel_laser_red.png"))
greenl = pg.image.load(os.path.join("assets", "pixel_laser_green.png"))
bluel = pg.image.load(os.path.join("assets", "pixel_laser_blue.png"))



background = pg.transform.scale(pg.image.load(os.path.join("assets", "sand.png")), (WIDTH, HEIGHT))

class Laser:
    def __init__(self, x, y, img):
        self.x = x
        self.y = y
        self.img = img
        self.mask = pygame.mask.from_surface(self.img)

    def draw(self, window):
        window.blit(self.img, (self.x, self.y))

    def move(self, vel):
        self.y += vel

    def off_screen(self, height):
        return not(self.y <= height and self.y >= 0)
    def collision(self, obj):
        return collide(self, obj)


class Ship:
    COOLDOWN = 30

    def __init__(self, x, y, health=100):
        self.x = x
        self.y = y
        self.health = health
        self.ship_img = None
        self.laser_img = None
        self.lasers = []
        self.cool_down_counter = 0
    def draw(self, window):
        window.blit(self.ship_img, (self.x, self.y))
        for laser in self.lasers:
            laser.draw(window)

    def move_lasers(self, vel, obj):
        self.cooldown()
        for laser in self.lasers:
            laser.move(vel)
            if laser.off_screen(HEIGHT):
                self.lasers.remove(laser)
            elif laser.collision(obj):
                obj.health -= 10
                self.lasers.remove(laser)

    def cooldown(self):
        if self.cool_down_counter >= self.COOLDOWN:
            self.cool_down_counter = 0
        elif self.cool_down_counter > 0:
            self.cool_down_counter += 1

    def shoot(self):
        if self.cool_down_counter == 0:
            laser = Laser(self.x, self.y, self.laser_img)
            self.lasers.append(laser)
            self.cool_down_counter = 1

    def get_width(self):
        return self.ship_img.get_width()

    def get_height(self):
        return self.ship_img.get_height()


class Player(Ship):
    def __init__(self, x, y, health=100):
        super().__init__(x, y, health)
        self.ship_img = playerss
        self.laser_img = playerl
        self.mask = pygame.mask.from_surface(self.ship_img)
        self.max_health = health
    def move_lasers(self, vel, objs):
        self.cooldown()
        for laser in self.lasers:
            laser.move(vel)
            if laser.off_screen(HEIGHT):
                self.lasers.remove(laser)
            else:
                for obj in objs:
                    if laser.collision(obj):
                        objs.remove(obj)
                        if laser in self.lasers:
                            self.lasers.remove(laser)

    def draw(self, window):
        super().draw(window)
        self.healthbar(window)

    def healthbar(self, window):
        pg.draw.rect(window, (255,0,0), (self.x, self.y + self.ship_img.get_height() + 10, self.ship_img.get_width(), 10))
        pg.draw.rect(window, (0,255,0), (self.x, self.y + self.ship_img.get_height() + 10, self.ship_img.get_width() * (self.health/self.max_health), 10))


class Enemy(Ship):
    COLOR_MAP = 
                "l1": (llama1, bluel),
                "l2": (llama2, bluel),
                "l3": (llama3, bluel),
                "l4": (llama4, bluel)
                
    def __init__(self, x, y, color, health=100):
        super().__init__(x, y, health)
        self.ship_img, self.laser_img = self.COLOR_MAP[color]
        self.mask = pg.mask.from_surface(self.ship_img)
    def move(self, vel):
        self.y += vel

    def shoot(self):
        if self.cool_down_counter == 0:
            laser = Laser(self.x-20, self.y, self.laser_img)
            self.lasers.append(laser)
            self.cool_down_counter = 1


def collide(obj1, obj2):
    offset_x = obj2.x - obj1.x
    offset_y = obj2.y - obj1.y
    return obj1.mask.overlap(obj2.mask, (offset_x, offset_y)) != None

def main():
    run = True
    FPS = 60
    level = 0
    lives = 5
    main_font = pg.font.SysFont("comicsans", 50)
    lost_font = pg.font.SysFont("comicsans", 60)

    enemies = []
    wave_length = 5
    enemy_vel = 1

    player_vel = 5
    laser_vel = 5

    player = Player(300, 630)

    clock = pg.time.Clock()

    lost = False
    lost_count = 0

    def redraw_window():
        WIN.blit(background, (0,0))
        # draw text
        lives_label = main_font.render(f"Lives: lives", 1, (255,255,255))
        level_label = main_font.render(f"Level: level", 1, (255,255,255))

        WIN.blit(lives_label, (10, 10))
        WIN.blit(level_label, (WIDTH - level_label.get_width() - 10, 10))
        for enemy in enemies:
            enemy.draw(WIN)

        player.draw(WIN)

        if lost:
            lost_label = lost_font.render("You Lost!!", 1, (255,255,255))
            WIN.blit(lost_label, (WIDTH/2 - lost_label.get_width()/2, 350))

        pg.display.update()

    while run:
        clock.tick(FPS)
        redraw_window()

        if lives <= 0 or player.health <= 0:
            lost = True
            lost_count += 1
        if lost:
            if lost_count > FPS * 3:
                run = False
            else:
                continue
        if len(enemies) == 0:
            level += 1
            wave_length += 5
            for i in range(wave_length):
                enemy = Enemy(random.randrange(50, WIDTH-100), random.randrange(-1500, -100), random.choice(["llama1", "llama2", "llama3"]))
                enemies.append(enemy)

        for event in pg.event.get():
            if event.type == pg.QUIT:
                quit()

        keys = pg.key.get_pressed()
        if (keys[pg.K_a] or keys[pg.K_LEFT])and player.x - player_vel > 0: # left
            player.x -= player_vel
        if (keys[pg.K_d] or keys[pg.K_RIGHT]) and player.x + player_vel + player.get_width() < WIDTH: # right
            player.x += player_vel
        if (keys[pg.K_w] or keys[pg.K_UP]) and player.y - player_vel > 0: # up
            player.y -= player_vel
        if (keys[pg.K_s] or keys[pg.K_DOWN]) and player.y + player_vel + player.get_height() + 15 < HEIGHT: # down
            player.y += player_vel
        if keys[pg.K_SPACE]:
            player.shoot()

        for enemy in enemies[:]:
            enemy.move(enemy_vel)
            enemy.move_lasers(laser_vel, player)

            if random.randrange(0, 2*60) == 1:
                enemy.shoot()

            if collide(enemy, player):
                player.health -= 10
                enemies.remove(enemy)
            elif enemy.y + enemy.get_height() > HEIGHT:
                lives -= 1
                enemies.remove(enemy)

        player.move_lasers(-laser_vel, enemies)

def main_menu():
    title_font = pg.font.SysFont("comicsans", 70)
    directions_font = pg.font.SysFont("comicsans", 50)
    cwhite = 255,255,255
    cother = 176, 0, 155
    run = True
    while run:
        WIN.blit(background, (0,0))
        title_label = title_font.render("Press the mouse to begin...", 1, (cwhite))
        directions_label = directions_font.render("SPACE:shoot W/UP:up S/DOWN:down", 1, (cother))
        directions2_label = directions_font.render("A/LEFT-ARROW:left ", 1, (cother))
        directions3_label = directions_font.render("D/RIGHT-ARROW:right   ", 1, (cother))
        directions4_label = directions_font.render("You can move all around the screen, ", 1, (cother))
        directions5_label = directions_font.render("but if you gethit by a laser or ", 1, (cother))
        directions6_label = directions_font.render("spaceship your helth is decreased ", 1, (cother))
        directions7_label = directions_font.render("if a ship pases beyond the screen ", 1, (cother))
        directions8_label = directions_font.render("you lose a life(shown in right corner).", 1, (cother))
        WIN.blit(title_label, (WIDTH/2 - title_label.get_width()/2, 200))
        WIN.blit(directions_label, (WIDTH/2 - directions_label.get_width()/2, 300))
        WIN.blit(directions2_label, (WIDTH/2 - directions_label.get_width()/2, 350))
        WIN.blit(directions3_label, (WIDTH/2 - directions_label.get_width()/2, 400))
        WIN.blit(directions4_label, (WIDTH/2 - directions_label.get_width()/2, 450))
        WIN.blit(directions5_label, (WIDTH/2 - directions_label.get_width()/2, 500))
        WIN.blit(directions6_label, (WIDTH/2 - directions_label.get_width()/2, 550))
        WIN.blit(directions7_label, (WIDTH/2 - directions_label.get_width()/2, 600))
        WIN.blit(directions8_label, (WIDTH/2 - directions_label.get_width()/2, 650))
        pg.display.update()
        for event in pg.event.get():
            if event.type == pg.QUIT:
                run = False
            if event.type == pg.MOUSEBUTTONDOWN:
                main()
    pg.quit()


main_menu()

【问题讨论】：

请修剪您的代码，以便更容易找到您的问题。请按照以下指南创建minimal reproducible example。

【参考方案1】：

COLORMAP 正在使用字符串 "l1"、"l2"、"l3"。因此，您应该在它们之间进行选择并使用random.choice(["l1", "l2", "l3"])。