更新分数Pygame Pong

Question

无论出于何种原因，我的乒乓球比赛中的比分显示没有更新。它只是说“0”。我查看了比分是否真的在游戏逻辑中更新，并且（打印出来给控制台）。每当新的显示画面被绘制时，我都会将文字“blitted”，所以任何人都可以告诉我为什么它不会更新？

import pygame 
import random 
pygame.init() 

# Create colors 
BLACK = (0, 0, 0) 
WHITE = (255, 255, 255) 

# Create screen and set screen caption 
size = (700, 500) 
screen = pygame.display.set_mode(size) 
pygame.display.set_caption("Pong") 

# Loop until user clicks close button 
done = False 

# Used to manage how fast the screen is updated 
clock = pygame.time.Clock() 

# Create player class 
class Player(): 

    # Initialize player paddles 
    def __init__(self, x, y, color, height, width): 
     self.x = x 
     self.y = y 
     self.color = color 
     self.height = height 
     self.width = width 
     self.y_speed = 0 
     self.score = 0 
     self.font = pygame.font.SysFont('Calibri', 24, True, False) 
     self.display_score = self.font.render("Score: %d " % (self.score), True, WHITE) 

    # Updates with new position of paddle every frame 
    def draw(self, y): 
     pygame.draw.rect(screen, self.color, [self.x, y, self.height, self.width]) 

    # Keeps paddle from going off screen 
    def keepOnScreen(self): 
     if self.y < 0: 
      self.y = 0 
     elif self.y > 410: 
      self.y = 410 

# Create Ball class 
class Ball(): 

    # Initialize ball in the middle of the screen with no movement 
    def __init__(self, color, height, width): 
     self.x = 325 
     self.y = random.randrange(150, 350) 
     self.color = color 
     self.height = height 
     self.width = width 
     self.y_speed = 0 
     self.x_speed = 0 

    # Updates new position of ball every frame 
    def draw(self, x, y): 
     pygame.draw.rect(screen, self.color, [x, y, self.height, self.width]) 

# Create instances of both players and ball 
player1 = Player(50, 100, WHITE, 25, 90) 
player2 = Player(625, 100, WHITE, 25, 90) 
ball = Ball(WHITE, 20, 20) 

# --- Main Program Loop --- 
while not done: 
    # --- Main event loop 
    for event in pygame.event.get(): # User did something 
     if event.type == pygame.QUIT: # If user clicked close 
      done = True # We are done so we exit this loop 

     if event.type == pygame.KEYDOWN: # Players utilize keyboard to move paddles 
      if event.key == pygame.K_w: 
       player1.y_speed = -6 
      if event.key == pygame.K_UP: 
       player2.y_speed = -6 
      if event.key == pygame.K_s: 
       player1.y_speed = 6 
      if event.key == pygame.K_DOWN: 
       player2.y_speed = 6 
      if event.key == pygame.K_SPACE: # Starts the ball movement 
       ball.x_speed = 3 * random.randrange(-1, 1, 2) 
       ball.y_speed = 3 * random.randrange(-1, 1, 2) 
     if event.type == pygame.KEYUP: 
      if event.key == pygame.K_w: 
       player1.y_speed = 0 
      if event.key == pygame.K_UP: 
       player2.y_speed = 0 
      if event.key == pygame.K_s: 
       player1.y_speed = 0 
      if event.key == pygame.K_DOWN: 
       player2.y_speed = 0 

    # Calculate the movement of the players 
    player1.y += player1.y_speed 
    player2.y += player2.y_speed 

    # Prevents paddles from going off-screen 
    player1.keepOnScreen() 
    player2.keepOnScreen() 

    # Checks to see if ball has made contact with paddle, then reverses direction of the ball 
    # Had to give a 4 pixel buffer since the ball won't always exactly hit the same part of paddle in x direction 
    if ball.x <= player1.x + 27 and (ball.x >= player1.x + 23): 
     if ball.y >= player1.y and (ball.y <= player1.y + 100): 
      ball.x_speed *= -1 
    if ball.x >= player2.x - 27 and (ball.x <= player2.x - 23): 
     if ball.y >= player2.y and (ball.y <= player2.y + 100): 
      ball.x_speed *= -1 

    # Checks to see if ball has made contact with top or bottom of screen 
    if ball.y <= 0 or ball.y >= 480: 
     ball.y_speed *= -1 

    # Calculates movement of the ball 
    ball.x += ball.x_speed 
    ball.y += ball.y_speed 

    # Updates score 
    if ball.x < 0: 
     player2.score += 1 
     ball.__init__(WHITE, 20, 20) 

    if ball.x > 700: 
     player1.score += 1 
     ball.__init__(WHITE, 20, 20) 

    # Set background 
    screen.fill(BLACK) 

    # Draw players and ball on screen 
    player1.draw(player1.y) 
    player2.draw(player2.y) 
    ball.draw(ball.x, ball.y) 
    screen.blit(player1.display_score, [0, 0]) 
    screen.blit(player2.display_score, [615, 0]) 

    # Update display 
    pygame.display.flip() 

    # Limit to 60 frames per second 
    clock.tick(60) 

# Close the window and quit 
pygame.quit() 

Answer 1

它看起来像这个问题是你每个玩家的display_score只在其__init__功能设置。

# Initialize player paddles 
def __init__(self, x, y, color, height, width): 
    ... 
    self.score = 0 
    ... 
    self.display_score = self.font.render("Score: %d " % (self.score), True, WHITE) 

的因为你初始化变量的方式，改变player.score值不会改变player.display_score值。

解决方案1 ​​

当你改变球员的得分，这将通过函数调用来轻松完成你可以改变的display_score值：

在你的游戏循环

def player_scores(player, ball): 
    player.score += 1 
    player.display_score = player.font.render("Score: %d " % (player.score), True, WHITE) 
    ball.__init__(WHITE, 20, 20) 

然后：

# Updates score 
if ball.x < 0: 
    player_scores(player2, ball) 

if ball.x > 700: 
    player_scores(player1, ball) 

解决方案2

您可以在显示乐谱文本时呈现乐谱文本，而不是在播放器上创建乐谱文本。在你的游戏循环：

screen.blit(player1.font.render("Score: %d " % (player1.score), True, WHITE), [0, 0]) 
    screen.blit(player2.font.render("Score: %d " % (player2.score), True, WHITE), [615, 0]) 

这将无效并display_score变量完全