python - Pygame:使用 time.sleep 延迟轮询 REST 响应的函数会卡住游戏窗口

Question

我实际上正在编写一个多用户 pygame 游戏，其中客户端通过 REST 请求与服务器进行通信。我有一个功能，游戏必须等到另一个玩家进入服务器上的“队列”才能开始新游戏。我通过使用 get-Request (通过请求完成)轮询服务器来完成此操作，中间有 time.sleep-delay 。但这次 time.sleep 也会导致我的游戏循环停止，并在等待时卡住我的游戏窗口。但我想让用户在等待期间离开游戏队列。这是不可能的，因为我的屏幕被卡住并变成“离开队列”对话框未显示，并且用户无法单击此按钮，甚至无法单击右上角的“x”来离开队列。

我已经尝试将轮询功能作为线程启动，但这并不能解决屏幕卡住/游戏循环停止的问题。

Answer 1

关于如何实现这项工作的几个关键点:

• 在线程中处理所有套接字 I/O
• 发送 Pygame Events当套接字事件发生时返回主循环
• 不要休眠或延迟你的主要 pygame 事件循环。曾经。

这是一个 Socket-Listener 线程示例，它将事件发送回主 pygame 线程。我对代码的长度表示歉意，但我想用一些功能完整的东西来回答。

import threading
import pygame
import random
import enum
import socket
import select
import time


### Event types that are sent to the main event loop
class NetworkEvents( enum.IntEnum ):
    EVENT_HANGUP    = pygame.USEREVENT + 1
    EVENT_COMMAND   = pygame.USEREVENT + 2


### Socket-listener thread that reads commands from the server
### and does the parsing and posting of commands to the main event-loop
class ConversationHandlerThread( threading.Thread ):
    """ A thread that handles a conversation with a single remote server.
        Accepts commands of 'close', 'red', 'green' or 'blue', and posts messages
        to the main PyGame thread for processing """
    def __init__( self, server_address, server_port ):
        threading.Thread.__init__(self)
        self.server_address = server_address
        self.server_port    = server_port
        self.server_socket  = None
        self.data_buffer    = ''
        self.daemon         = True # exit with parent
        self.done           = False

    def stop( self ):
        self.done = True

    def connect( self ):
        self.server_socket = socket.socket( socket.AF_INET, socket.SOCK_STREAM )
        while True:
            try:  
                self.server_socket.connect( ( self.server_address, self.server_port ) )
                break;
            except:
                print( "Failed to connect %s:%d, will retry" % ( self.server_address, self.server_port ) )
                time.sleep( 12 )

    def run( self ):
        """ Connects to Server, then Loops until the server hangs-up """
        self.connect()

        # Now we're connected, start reading commands
        read_events_on   = [ self.server_socket ]
        while ( not self.done ):
            # Wait for incoming data, or errors, or 0.5 seconds
            (read_list, write_list, except_list) = select.select( read_events_on, [], [], 0.5 )

            if ( len( read_list ) > 0 ):
                # New data arrived, read it
                incoming = self.server_socket.recv( 8192 )
                if ( len(incoming) == 0):
                    # Socket has closed
                    new_event = pygame.event.Event( NetworkEvents.EVENT_HANGUP, { "address" : self.server_address } )
                    pygame.event.post( new_event )
                    self.server_socket.close()
                    self.done = True
                else:
                    # Data has arrived
                    try:
                        new_str = incoming.decode('utf-8')
                        self.data_buffer += new_str
                    except: 
                        pass # don't understand buffer

                    # Parse incoming message (trivial parser, not high quality) 
                    # commands are '\n' separated
                    if (self.data_buffer.find('\n') != -1 ):
                        for command in self.data_buffer.split('\n'):
                            command = line.strip()
                            # client disconnect command
                            if ( command == 'close' ):
                                new_event = pygame.event.Event( NetworkEvents.EVENT_HANGUP, { "address" : self.server_address } )
                                pygame.event.post( new_event )
                                self.server_socket.close()
                                self.done = True

                            # only make events for valid commands
                            elif ( command in ( 'red', 'green', 'blue' ) ):
                                new_event = pygame.event.Event( NetworkEvents.EVENT_COMMAND, { "address" : self.server_address, "message" : command  } )
                                pygame.event.post( new_event )
                        self.data_buffer = ''  # all used-up


### MAIN

# Start the connection-listener thread
thread1 = ConversationHandlerThread( '127.0.0.1', 5555 )
thread1.start()

一旦线程运行，就会在主循环中接收事件，就像任何其他 PyGame 事件一样:

# Main paint / update / event loop
done = False
while ( not done ):
    SPRITES.update()

    for event in pygame.event.get():
        if ( event.type == pygame.QUIT ):
            done = True

        elif ( event.type == NetworkEvents.EVENT_HANGUP ):
            print(" CLIENT DISCONNECTED %s " % ( str(event.address) ) )

        elif ( event.type == NetworkEvents.EVENT_COMMAND ):
            print(" CLIENT MESSAGE FROM %s - %s " % ( str(event.address), event.message ) )
            if ( event.message == 'red' ):
                new_sprite = AlienSprite( RED )
                SPRITES.add( new_sprite )
    # ... etc.

如果您的套接字 I/O 在线程中处理，并且主事件循环从不休眠，您应该能够使用 PyGame 制作一个流畅的程序。保持您的网络流量小而简洁。