pygame没有更新draw.rect，尽管x和y值正在更新

Question

我对编程还很陌生，我只是一个初学者项目。我已经编写了以下代码来尝试移动两个拨杆，但当按下上/下/w/s键时，它们都不会移动。然而，在尝试自己调试时，我将其设置为将x和y值打印到控制台，看看这是否是问题所在，x和y的值正在更新，但矩形的坐标没有。我确信这是一个相当简单的修复方法，但我对编程还很陌生，只是不知道出了什么问题。这是我的代码：

import time
pygame.init()
screenW = 800
screenH = 600
win = pygame.display.set_mode((screenW, screenH))
pygame.display.set_caption("Pong")
clock = pygame.time.Clock()
font = pygame.font.SysFont("comicsans", 20)
paddleW = 20
paddleH = 100
ballSpeed = 15
class paddle(object):
def __init__(self, x, y, width, height):
self.x = x
self.y = y
self.width = width
self.height = height
self.pad = (self.x, self.y, self.width, self.height)
def draw(self, win):
pygame.draw.rect(win, (255,255,255), self.pad)
class ball(object):
def __init__(self, x, y, side):
self.x = x
self.y = y
self.side = side
self.pad = (self.x, self.y, self.side, self.side)
def draw(self, win):
pygame.draw.rect(win, (255,255,255), self.pad)
def redrawGameWindow():
win.fill((0,0,0))
paddleLeft.draw(win)
paddleRight.draw(win)
theBall.draw(win)
pygame.display.update()

#Main Loop:
paddleLeft = paddle(10, screenH//2, paddleW, paddleH)
paddleRight = paddle(screenW - 10 - paddleW, screenH//2, paddleW, paddleH)
theBall = ball(screenW//2, screenH//2, 30)
run = True
while run:
clock.tick(30)

for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
keys = pygame.key.get_pressed()
if keys[pygame.K_UP]:
print("left up")
print(paddleRight.y)
paddleRight.y -= ballSpeed
elif keys[pygame.K_DOWN]:
print("left down")
print(paddleRight.y)
paddleRight.y += ballSpeed
elif keys[pygame.K_w]:
print("right up")
print(paddleLeft.y)
paddleLeft.y -= ballSpeed
elif keys[pygame.K_s]:
print("right down")
print(paddleLeft.y)
paddleLeft.y += ballSpeed
redrawGameWindow()

pygame.quit()

Answer 1

当您更改属性x和y时，列表pad的内容不会神奇地更改。

绘制之前，必须更新.pad。例如：

class paddle(object):
# [...]
def draw(self, win):
self.pad = (self.x, self.y, self.width, self.height)
pygame.draw.rect(win, (255,255,255), self.pad)

无论如何，我建议使用pygame.Rect对象，而不是属性x、y、width和height:

class paddle(object):
def __init__(self, x, y, width, height):
self.rect = pygame.Rect(x, y, width, height)
def draw(self, win):
pygame.draw.rect(win, (255,255,255), self.rect)
class ball(object):
def __init__(self, x, y, side):
self.rect = pygame.Rect(x, y, side, side)
def draw(self, win):
pygame.draw.rect(win, (255,255,255), self.rect)

---

完整示例：

import pygame
import time
pygame.init()
screenW = 800
screenH = 600
win = pygame.display.set_mode((screenW, screenH))
pygame.display.set_caption("Pong")
clock = pygame.time.Clock()
font = pygame.font.SysFont("comicsans", 20)
paddleW = 20
paddleH = 100
ballSpeed = 15
class paddle(object):
def __init__(self, x, y, width, height):
self.rect = pygame.Rect(x, y, width, height)
def draw(self, win):
pygame.draw.rect(win, (255,255,255), self.rect)
class ball(object):
def __init__(self, x, y, side):
self.rect = pygame.Rect(x, y, side, side)
def draw(self, win):
pygame.draw.rect(win, (255,255,255), self.rect)
def redrawGameWindow():
win.fill((0,0,0))
paddleLeft.draw(win)
paddleRight.draw(win)
theBall.draw(win)
pygame.display.update()

#Main Loop:
paddleLeft = paddle(10, screenH//2, paddleW, paddleH)
paddleRight = paddle(screenW - 10 - paddleW, screenH//2, paddleW, paddleH)
theBall = ball(screenW//2, screenH//2, 30)
run = True
while run:
clock.tick(30)

for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
keys = pygame.key.get_pressed()
if keys[pygame.K_UP]:
print("left up")
print(paddleRight.rect.y)
paddleRight.rect.y -= ballSpeed
elif keys[pygame.K_DOWN]:
print("left down")
print(paddleRight.rect.y)
paddleRight.rect.y += ballSpeed
elif keys[pygame.K_w]:
print("right up")
print(paddleLeft.rect.y)
paddleLeft.rect.y -= ballSpeed
elif keys[pygame.K_s]:
print("right down")
print(paddleLeft.rect.y)
paddleLeft.rect.y += ballSpeed
redrawGameWindow()

pygame.quit()