Question

我正在制作一个pygame程序来为sprite设置动画，但问题不是特定的错误：

import sys
import os
import pygame
from pygame.locals import *

pygame.init ()

WHITE = ( 255, 255, 255 )
BLACK = (   0,   0,   0 )

Surface = pygame.display.set_mode ((400, 400), 0, 32)
pygame.display.set_caption ('Animation Test')




class Processes (object):
    @staticmethod
    def load_image (imagefile):
        image = pygame.image.load (imagefile)   #Remember to call imagefile as a string statement

        return image, image.get_rect ()



class Sprite (pygame.sprite.Sprite):

    def __init__ (self):
        pygame.sprite.Sprite.__init__ (self)

        self.image, self.rect = Processes.load_image ('frame1.jpg')

        self.blindrect = pygame.Rect ((self.rect.top - 289, self.rect.left - 289), (self.rect.width, self.rect.height))




   def animation (self, key_event = None, mouse_event = None):

       blindpass = 0

       if key_event == K_LEFT:
       self.rect.centerx = self.rect.centerx - 10

       if key_event == K_RIGHT:
        self.rect.centerx = self.rect.centerx + 10

       if key_event == K_UP:
       self.rect.centery = self.rect.centery - 10

       if key_event == K_DOWN:
       self.rect.centery = self.rect.centery + 10


       if mouse_event == MOUSEBUTTONDOWN:
        self.rect.centerx, self.rect.centery = pygame.mouse.get_pos ()


    if blindpass > 0:

        if key_event == K_LEFT:
            self.blindrect.centerx = self.blindrect.centerx - 10

        if key_event == K_RIGHT:
            self.blindrect.centerx = self.blindrect.centerx + 10

        if key_event == K_UP:
            self.blindrect.centery = self.blindrect.centery - 10

        if key_event == K_DOWN:
            self.blindrect.centery = self.blindrect.centery + 10


        if mouse_event == MOUSEBUTTONDOWN:
            self.rect.centerx, self.rect.centery = pygame.mouse.get_pos () 




mecha = Sprite ()
allsprites = pygame.sprite.RenderPlain ((mecha, ))



while True:
Surface.fill (WHITE)

for event in pygame.event.get ():
    if event.type == KEYDOWN:
    mecha.animation (key_event = event.key)

    if event.type == MOUSEBUTTONDOWN:
    mecha.animation (mouse_event = event.type)

    if event.type == QUIT:
    pygame.quit ()
    sys.exit (0)



allsprites.draw (Surface)
pygame.display.update ((mecha.rect, mecha.blindrect))

现在，错误有点奇怪。输出是精灵确实出现在屏幕上，当我提供键和鼠标输入时，它会移动，但问题是它是否会留下痕迹。这就是为什么我创建了一个矩形来跟踪精灵矩形，每当游戏循环循环时，该矩形应该用白色填充。但事实并非如此。至少，直到我最小化窗口并再次将其拉起，所有路径都消失，背景变为白色而不是黑色。但是当我移动图像时，小径又开始形成。我尽量减少，它们会像预期的那样消失。

Answer 1

如果您的渲染功能执行：

screen.fill(white)
# blit or sprite group drawing
pygame.display.flip()

它将整个屏幕清除为白色，绘制精灵一次。不会有任何痕迹。

您的代码未正确粘贴。 f如果QUIT语句没有缩进，则表示多语句。与Sprite类相同
如果使用Surface或Sprite作为类/变量名称，则可能会出现命名问题。

Answer 2

您没有正确初始化和更新盲目。这就是为什么屏幕的正确部分没有更新，你的精灵正在留下痕迹。
在更新循环中，由于您只更新了更改的显示部分，因此在进入更新循环之前，需要更新整个屏幕一次以初始化它。这就是屏幕最初不是白色的原因。

请参阅下面更新的源代码（仅修改了Sprite类及更高版本）：

class Sprite (pygame.sprite.Sprite):
    def __init__ (self):
        pygame.sprite.Sprite.__init__ (self)
        self.image, self.rect = Processes.load_image ('frame1.jpg')
        #initialize blindrect to be the same rectangle as rect
        self.blindrect = pygame.Rect ((self.rect.top, self.rect.left), (self.rect.width, self.rect.height))

    def animation (self, key_event = None, mouse_event = None):
        print(self.rect)
        print(self.blindrect)

        #save the current sprite position before moving the sprite
        self.blindrect.centerx = self.rect.centerx
        self.blindrect.centery = self.rect.centery

        if key_event == K_LEFT:
            self.rect.centerx = self.rect.centerx - 10

        if key_event == K_RIGHT:
            self.rect.centerx = self.rect.centerx + 10

        if key_event == K_UP:
            self.rect.centery = self.rect.centery - 10

        if key_event == K_DOWN:
            self.rect.centery = self.rect.centery + 10

        if mouse_event == MOUSEBUTTONDOWN:
            self.rect.centerx, self.rect.centery = pygame.mouse.get_pos ()

        print(self.rect)
        print(self.blindrect)

mecha = Sprite ()
allsprites = pygame.sprite.RenderPlain ((mecha, ))

#need to initially fill the entire surface with white
Surface.fill (WHITE)
pygame.display.update ((pygame.Rect((0,0),(400,400))))

while True:
    Surface.fill (WHITE)

    for event in pygame.event.get ():
        if event.type == KEYDOWN:
            mecha.animation (key_event = event.key)

        if event.type == MOUSEBUTTONDOWN:
            mecha.animation (mouse_event = event.type)

        if event.type == QUIT:
            pygame.quit ()
            sys.exit (0)

    allsprites.draw (Surface)
    #update only the previous sprite position and new sprite position
    pygame.display.update ((mecha.rect, mecha.blindrect))

Pygame程序执行错误

2 个答案: