我正在尝试制作乒乓球游戏，但当球离开屏幕时得分不会改变。另一件不太正确的事情是，有时，球会在桨上滑动，然后离开屏幕，而不是从桨上弹开。我可以就这些问题获得一些帮助吗？ (主要是第一个)这是我的代码:
import pygame as pg
import random
from os import path
img_dir = path.join(path.dirname(__file__), 'img')
snd_dir = path.join(path.dirname(__file__), 'snd')
WIDTH = 1280
HEIGHT = 690
FPS = 60
# define colors
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
YELLOW = (0, 255, 255)
OPPONENT_SPEED = 2.4
# initialize PyGame and create window
pg.init()
pg.mixer.init()
screen = pg.display.set_mode((WIDTH, HEIGHT))
pg.display.set_caption('PONG!')
clock = pg.time.Clock()
pong_ball_x = [-3, 3]
pong_ball_y = [-3, 3]
font_name = pg.font.match_font('arial')
def draw_text(surf, text, size, x, y):
font = pg.font.Font(font_name, size)
text_surface = font.render(text, True, WHITE)
text_rect = text_surface.get_rect()
text_rect.midtop = (x, y)
surf.blit(text_surface, text_rect)
class Player(pg.sprite.Sprite):
def __init__(self):
pg.sprite.Sprite.__init__(self)
self.image = pg.Surface((5, 100))
self.image.fill(WHITE)
self.rect = self.image.get_rect()
self.rect.x = 10
self.rect.y = HEIGHT / 2
self.speedy = 0
def update(self):
self.speedy = 0
keys = pg.key.get_pressed()
if keys[pg.K_s]:
self.speedy = 5
if keys[pg.K_w]:
self.speedy = -5
self.rect.y += self.speedy
if self.rect.bottom >= HEIGHT:
self.rect.bottom = HEIGHT
if self.rect.top <= 0:
self.rect.top = 0
class Player2(pg.sprite.Sprite):
def __init__(self):
pg.sprite.Sprite.__init__(self)
self.image = pg.Surface((5, 100))
self.image.fill(WHITE)
self.rect = self.image.get_rect()
self.rect.x = WIDTH - 15
self.rect.y = HEIGHT / 2
self.speedy = 0
def update(self):
self.speedy = 0
keys = pg.key.get_pressed()
if keys[pg.K_DOWN]:
self.speedy = 5
if keys[pg.K_UP]:
self.speedy = -5
self.rect.y += self.speedy
if self.rect.bottom >= HEIGHT:
self.rect.bottom = HEIGHT
if self.rect.top <= 0:
self.rect.top = 0
class Opponent(pg.sprite.Sprite):
def __init__(self):
pg.sprite.Sprite.__init__(self)
self.image = pg.Surface((5, 100))
self.image.fill(WHITE)
self.rect = self.image.get_rect()
self.rect.x = WIDTH - 10
self.rect.y = HEIGHT / 2
self.speedy = 0
def update(self):
if self.rect.bottom >= HEIGHT:
self.rect.bottom = HEIGHT
if self.rect.top <= 0:
self.rect.top = 0
def opponent_ai(self):
if self.rect.top < pong_ball.rect.y:
self.rect.top += OPPONENT_SPEED
if self.rect.bottom > pong_ball.rect.y:
self.rect.bottom -= OPPONENT_SPEED
class PongBall(pg.sprite.Sprite):
def __init__(self):
pg.sprite.Sprite.__init__(self)
self.image = pg.Surface((30, 30))
self.image.fill(WHITE)
self.rect = self.image.get_rect()
self.rect.x = WIDTH / 2 - 12.5
self.rect.y = HEIGHT / 2 - 12.5
self.speedx = random.choice(pong_ball_x)
self.speedy = random.choice(pong_ball_y)
def update(self):
self.rect.x += self.speedx
self.rect.y += self.speedy
if self.rect.top <= 0:
self.speedy = -self.speedy
if self.rect.bottom >= HEIGHT:
self.speedy = -self.speedy
if self.rect.right <= 0:
self.rect.x = WIDTH / 2 - 15
self.rect.y = HEIGHT / 2 - 15
if self.rect.left >= WIDTH:
self.rect.x = WIDTH / 2 - 15
self.rect.y = HEIGHT / 2 - 15
def bounce(self):
self.speedx = -self.speedx
# load all game graphics
# ball_img = pg.image.load(path.join(img_dir, "white_circle2.png")).convert()
all_sprites = pg.sprite.Group()
pong_ball_group = pg.sprite.Group()
player = Player()
player2 = Player2()
opponent = Opponent()
pong_ball = PongBall()
all_sprites.add(player)
all_sprites.add(player2)
pong_ball_group.add(pong_ball)
score = 0
score2 = 0
# Game loop
running = True
while running:
# process input (events)
for event in pg.event.get():
# check for closing window
if event.type == pg.QUIT:
running = False
if pong_ball.rect.left == WIDTH - 12.5:
score = score + 1
if pong_ball.rect.right == 12.5:
score2 = score2 + 1
# update
all_sprites.update()
pong_ball_group.update()
# check to see if pong ball hit one of the pads
hits = pg.sprite.spritecollide(pong_ball, all_sprites, False, False)
for hit in hits:
pong_ball.bounce()
# draw and render
screen.fill(BLACK)
all_sprites.draw(screen)
pong_ball_group.draw(screen)
draw_text(screen, str(score), 50, WIDTH / 2 - 30, 10)
draw_text(screen, str(score2), 50, WIDTH / 2 + 30, 10)
draw_text(screen, "-", 50, WIDTH / 2, 10)
# *after* drawing everything, flip the display
pg.display.flip()
pg.quit()
最佳答案
问题在于如何检查球是否已离开屏幕。您当前的检查条件永远不会触发为 pong_ball.rect.left永远不会等于 WIDTH - 12.5因为它是一个整数。
一个简单的调试方法就是打印您正在检查的值，因此添加
print(pong_ball.rect.left, WIDTH - 12.5)
将输出:
1264 1267.5
1267 1267.5
1270 1267.5
1273 1267.5
1276 1267.5
1279 1267.5
625 1267.5
628 1267.5
当球移向屏幕右侧时，其位置就会重置。
因此，您会看到球的位置超出了您的极限，而没有触发您的条件。
如果将比较更改为 >和<分别，分数将更新。
但是这会导致另一个问题，从上面的调试打印中也可能很明显。有四个帧的评分条件为 true，因为重置位置检查在 PongBall.update() 中。没有12.5像素的余地。这就是存在余地的原因吗？ future 的你可能会欣赏您的评论。
但是，如果您更改比较以删除 12.5 像素缓冲区，则分数不会更新。这是因为pong_ball位置已更新并在其 update() 中重置。方法。
如果我们遵循您的退回方法，我们可以添加单独的 reset方法PongBall当我们满足评分标准时称之为。
所以你的PongBall现在上课:
class PongBall(pg.sprite.Sprite):
def __init__(self):
pg.sprite.Sprite.__init__(self)
self.image = pg.Surface((30, 30))
self.image.fill(WHITE)
self.rect = self.image.get_rect()
self.speedx = random.choice(pong_ball_x)
self.speedy = random.choice(pong_ball_y)
self.reset()
def update(self):
self.rect.x += self.speedx
self.rect.y += self.speedy
if self.rect.top <= 0:
self.speedy = -self.speedy
if self.rect.bottom >= HEIGHT:
self.speedy = -self.speedy
def reset(self):
self.rect.x = WIDTH / 2 - 15
self.rect.y = HEIGHT / 2 - 15
def bounce(self):
self.speedx = -self.speedx
您的主循环发生更改以执行重置:
while running:
# process input (events)
for event in pg.event.get():
# check for closing window
if event.type == pg.QUIT:
running = False
# check for score
if pong_ball.rect.left > WIDTH - 12.5:
score = score + 1
pong_ball.reset()
if pong_ball.rect.right < 12.5:
score2 = score2 + 1
pong_ball.reset()
# update
....
那么您的分数应该表现正确。
关于python - python pygame 中的分数没有变化，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/60767506/