如何在我的第一个 pygame Python 项目中移动火箭

如何解决如何在我的第一个 pygame Python 项目中移动火箭

如果您能帮助我解决在我的项目中移动 Rocket 的问题，我将不胜感激。

根据我在“Python 速成课程”一书中学到的材料，我已经开始编写我的第一个游戏。

我需要让火箭在游戏中移动到整个窗口并围绕它的轴移动。 一切正常（向左、向右、顶部、底部移动），然后我决定让我的火箭围绕它的轴移动。我花了很多时间来知道如何去做，而且它已经可以工作了（左 Shift）。 但现在我面临另一个问题。我的火箭现在不在屏幕上移动，而是绕着它的轴移动。我知道我的问题可能看起来很愚蠢，而且我的代码中的某处显然缺乏简单的逻辑。但是我尝试了几个小时自己修复它并没有得到结果。

这是我的代码：

import pygame
import sys




class Settings():
    """A class to store all settings for Rocket."""
    def __init__(self):
        """Initialize the game screen settings."""
        # Screen settings.
        self.screen_width = 900
        self.screen_height = 700
        self.bg_color = (21,36,110)

class Rocket():
    """A class that describes rocket."""
    def __init__(self,screen):
        """Initialize rocket and its starting position."""
        self.screen = screen
        #Load the rocket image and get its rect.
        self.image = pygame.image.load('/media/philip/9074-45DF/Python/rocket/images/rocket.png')
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()
        #set starting position of a rocket.
        self.rect.centerx = self.screen_rect.centerx
        self.rect.centery = self.screen_rect.centery
        #movement flag.
        self.moving_right = False
        self.moving_left = False
        self.moving_up = False
        self.moving_down = False
        self.rotate_left = False
        self.rocket_angle = 0


    def update(self):
        """Update the rocket position based on the movement flag."""
        if self.moving_right and self.rect.right < self.screen_rect.right:
            self.rect.centerx += 2
        if self.moving_left and self.rect.left > 0:
            self.rect.centerx -= 2
        if self.moving_up and self.rect.top > 0:
            self.rect.centery -= 2
        if self.moving_down and self.rect.bottom < self.screen_rect.bottom:
            self.rect.centery += 2 


    def rotated_center(self,image,rocket_angle):
        """Rotating rocket around its axis."""
        self.center = self.image.get_rect().center
        self.rotated_image = pygame.transform.rotate(self.image,self.rocket_angle)
        self.new_rect = self.rotated_image.get_rect(center = self.center)
        return self.rotated_image,self.new_rect                       


    def blit_rocket(self,rect,rocket_angle):
        """Draw the rocket at its current location."""       
        if self.rotate_left:
            self.rocket_angle = (self.rocket_angle + 1) % 360 
            self.screen.blit(self.rotated_image,self.new_rect) 
        else:
            self.rocket_angle = (self.rocket_angle + 0) % 360
            self.screen.blit(self.rotated_image,self.new_rect)    
           


    def check_events(self):
        """Respond to a key events."""
        # Responses to the keydown events.
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_RIGHT:
                self.moving_right = True
            if event.key == pygame.K_LEFT:
                self.moving_left = True
            if event.key == pygame.K_DOWN:
                self.moving_down = True 
            if event.key == pygame.K_UP:
                self.moving_up = True 
            if event.key == pygame.K_LSHIFT:
                self.rotate_left = True    

        # Responses to the keyup events.
        if event.type == pygame.KEYUP:
            if event.key == pygame.K_RIGHT:
                self.moving_right = False
            if event.key == pygame.K_LEFT:
                self.moving_left = False
            if event.key == pygame.K_DOWN:
                self.moving_down = False 
            if event.key == pygame.K_UP:
                self.moving_up = False  
            if event.key == pygame.K_LSHIFT:
                self.rotate_left = False        

       



pygame.init()
rocket_settings = Settings()
icon = pygame.image.load('/media/philip/9074-45DF/Python/rocket/images/rocket_icon.png')


pygame.display.set_icon(icon)
screen = pygame.display.set_mode((rocket_settings.screen_width,rocket_settings.screen_height))
pygame.display.set_caption("Rocket")
rocket = Rocket(screen)

"""The main game loop."""
while True:  
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()    

    screen.fill((rocket_settings.bg_color))
    rocket.update()
    rocket.check_events()
    rocket.rotated_center(rocket.image,rocket.rocket_angle)
    rocket.blit_rocket(rocket.rect,rocket.rocket_angle)  
    pygame.display.flip()
   

解决方法

event 必须是方法 Rocket.check_events 的参数：

class Rocket():
    # [...]

    def check_events(self,event):               # event argument
        """Respond to a key events."""
        # Responses to the keydown events.
        # [...]

您必须在事件循环中调用 rocket.check_events() 并将 event 传递给方法：

while True:  
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()

        rocket.check_events(event)                          # <--- ADD

    screen.fill((rocket_settings.bg_color))
    rocket.update()                               
    # rocket.check_events()                                   <--- DELETE
    rocket.rotated_center(rocket.image,rocket.rocket_angle)
    rocket.blit_rocket(rocket.rect,rocket.rocket_angle)  
    pygame.display.flip()

---

pygame.Surface.get_rect.get_rect() 返回一个具有 Surface 对象大小的矩形，但它返回一个始终从 (0,0) 开始的矩形。
您必须从 self.rect.center 而不是 self.image.get_rect().center 获取对象的位置：

class Rocket():
    # [...]

    def rotated_center(self,image,rocket_angle):
        """Rotating rocket around its axis."""
        self.rotated_image = pygame.transform.rotate(self.image,self.rocket_angle)
        self.new_rect = self.rotated_image.get_rect(center = self.rect.center)
        return self.rotated_image,self.new_rect 

---

完整示例：

import pygame
import sys


class Settings():
    """A class to store all settings for Rocket."""
    def __init__(self):
        """Initialize the game screen settings."""
        # Screen settings.
        self.screen_width = 900
        self.screen_height = 700
        self.bg_color = (21,36,110)

class Rocket():
    """A class that describes rocket."""
    def __init__(self,screen):
        """Initialize rocket and its starting position."""
        self.screen = screen
        #Load the rocket image and get its rect.
        self.image = pygame.image.load('/media/philip/9074-45DF/Python/rocket/images/rocket.png')
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()
        #set starting position of a rocket.
        self.rect.centerx = self.screen_rect.centerx
        self.rect.centery = self.screen_rect.centery
        #movement flag.
        self.moving_right = False
        self.moving_left = False
        self.moving_up = False
        self.moving_down = False
        self.rotate_left = False
        self.rocket_angle = 0


    def update(self):
        """Update the rocket position based on the movement flag."""
        if self.moving_right and self.rect.right < self.screen_rect.right:
            self.rect.centerx += 2
        if self.moving_left and self.rect.left > 0:
            self.rect.centerx -= 2
        if self.moving_up and self.rect.top > 0:
            self.rect.centery -= 2
        if self.moving_down and self.rect.bottom < self.screen_rect.bottom:
            self.rect.centery += 2 


    def rotated_center(self,self.new_rect                       


    def blit_rocket(self,rect,rocket_angle):
        """Draw the rocket at its current location."""       
        if self.rotate_left:
            self.rocket_angle = (self.rocket_angle + 1) % 360 
            self.screen.blit(self.rotated_image,self.new_rect) 
        else:
            self.rocket_angle = (self.rocket_angle + 0) % 360
            self.screen.blit(self.rotated_image,self.new_rect)    
           


    def check_events(self,event):
        """Respond to a key events."""
        # Responses to the keydown events.
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_RIGHT:
                self.moving_right = True
            if event.key == pygame.K_LEFT:
                self.moving_left = True
            if event.key == pygame.K_DOWN:
                self.moving_down = True 
            if event.key == pygame.K_UP:
                self.moving_up = True 
            if event.key == pygame.K_LSHIFT:
                self.rotate_left = True    

        # Responses to the keyup events.
        if event.type == pygame.KEYUP:
            if event.key == pygame.K_RIGHT:
                self.moving_right = False
            if event.key == pygame.K_LEFT:
                self.moving_left = False
            if event.key == pygame.K_DOWN:
                self.moving_down = False 
            if event.key == pygame.K_UP:
                self.moving_up = False  
            if event.key == pygame.K_LSHIFT:
                self.rotate_left = False        

       



pygame.init()
rocket_settings = Settings()
icon = pygame.image.load('/media/philip/9074-45DF/Python/rocket/images/rocket_icon.png')


pygame.display.set_icon(icon)
screen = pygame.display.set_mode((rocket_settings.screen_width,rocket_settings.screen_height))
pygame.display.set_caption("Rocket")
rocket = Rocket(screen)

"""The main game loop."""
while True:  
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()    

        rocket.check_events(event)

    screen.fill((rocket_settings.bg_color))
    rocket.update()
    rocket.rotated_center(rocket.image,rocket.rocket_angle)  
    pygame.display.flip()