Twisted clients within pygame mainloop?

Question

I'm trying to run a twisted-server with pygame-clients:

class ChatClientProtocol(LineReceiver):
    def lineReceived(self,line):
        print (line)

class ChatClient(ClientFactory):
    def __init__(self):
        self.protocol = ChatClientProtocol

def main():
    flag = 0
    default_screen()
    while True:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                return
            elif event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE:
               return
            elif event.type == pygame.MOUSEBUTTONDOWN and event.button == 1:
                pos = pygame.mouse.get_pos()
                # some rect.collidepoint(pos) rest of loop... 

And here is the server:

from twisted.internet.protocol import Factory
from twisted.protocols.basic import LineReceiver
from twisted.internet import reactor

class Chat(LineReceiver):
    def __init__(self, users, players):
        self.users = users
        self.name = None
        self.players = players

    def connectionMade(self):
        new = 'player_' + str(len(self.players) + 1)
        self.players.append(new)
        self.sendLine(str(self.players,))

class ChatFactory(Factory):
    def __init__(self):
        self.users = {} #maps instances to clients 
        self.players = []

    def buildProtocol(self, addr):
        return Chat(self.users,self.players)


reactor.listenTCP(6000, ChatFactory())
reactor.run()

I'm running this server with the client code with out the reactor.CallLater() method and pygames code and the client connects fine. Am I using the reactor method wrong or is there something structurally wrong with the pygames code? Any help would be appreciated.

So I don't know if the loop within the pygames bit ever breaks to call the reactor again?

Answer 1

You should not write your own main loop (with while) when using twisted. twisted has to control the main loop, and pygame is flexible enough to not care about (it does not need its own loop).

You should put everything which is inside your main loop into a function, and shedule it with the twisted reactor by calling reactor.CallLater()

def main():
    flag = 0
    default_screen()
    reactor.callLater(0.1, tick)

def tick():
   for event in pygame.event.get():
        if event.type == pygame.QUIT:
            reactor.stop() # just stop somehow
        elif event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE:
            reactor.stop() # just stop somehow
        elif event.type == pygame.MOUSEBUTTONDOWN and event.button == 1:
            pos = pygame.mouse.get_pos()
            # some stuff
   reactor.callLater(0.1, tick)

This way, you ensure the reactor runs and can handle network events.

---

Here's a small working example of a client that will just render the last line recieved:

from twisted.internet import reactor
from twisted.internet.protocol import ClientFactory
from twisted.protocols.basic import LineReceiver

import pygame

class ChatClientProtocol(LineReceiver):

    def __init__(self, recv):
        self.recv = recv

    def lineReceived(self,line):
        self.recv(line)

class ChatClient(ClientFactory):
    def __init__(self, recv):
        self.protocol = ChatClientProtocol
        self.recv = recv

    def buildProtocol(self, addr):
        return ChatClientProtocol(self.recv)

class Client(object):

    def __init__(self):
        self.line = 'no message'
        pygame.init()
        self.screen = pygame.display.set_mode((200, 200))
        reactor.callLater(0.1, self.tick)

    def new_line(self, line):
        self.line = line

    def tick(self):
        self.screen.fill((0,0,0))
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                reactor.stop() # just stop somehow
            elif event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE:
                reactor.stop() # just stop somehow
        self.screen.blit(pygame.font.SysFont('mono', 12, bold=True).render(self.line, True, (0, 255, 0)), (20,20))
        pygame.display.flip()
        reactor.callLater(0.1, self.tick)

if __name__ == '__main__':
    c = Client()
    reactor.connectTCP('127.0.0.1',6000, ChatClient(c.new_line))    
    reactor.run()

---

Here's a simple example using LoopingCall, as Glyph suggested (I left out the protocoll/factory classes as they're the same as above):

from twisted.internet.task import LoopingCall

class Client(object):

    def __init__(self):
        self.line = 'no message'
        pygame.init()
        self.screen = pygame.display.set_mode((200, 200))

    def new_line(self, line):
        self.line = line

    def tick(self):
        self.screen.fill((0,0,0))
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                reactor.stop() # just stop somehow
            elif event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE:
                reactor.stop() # just stop somehow
        self.screen.blit(pygame.font.SysFont('mono', 12, bold=True).render(self.line, True, (0, 255, 0)), (20,20))
        pygame.display.flip()

if __name__ == '__main__':
    c = Client()

    lc = LoopingCall(c.tick)
    lc.start(0.1)
    reactor.connectTCP('127.0.0.1',6000, ChatClient(c.new_line))    
    reactor.run()