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Re: [pygame] Pausing a function



Hi

yes, python has a priority queue: heapq (standard module)

~DR0ID

Michael George schrieb:
In fact, now that I think about it for a few more minutes, it might make sense to yield the time for the next update. Not sure if python has a built-in priority queue class, but if so you could do something like the following (pseudocode, sorry):

queue = new PQ()
queue.add(anim1_start_time, anim1)
queue.add(anim2_start_time, anim2)
while playing:
   # handle events
   while queue.next_time <= now:
      a = queue.next()
      try:
         queue.add(a.next(), a)
      except StopIteration:
         pass

Then each animation method can sleep until a given time t by yielding t.

--Mike

Michael George wrote:
You might be able to restructure your code a little less if you use generators to simulate coroutines. For example:

def anim1():
   for frame in frames:
      self.image = frame
      yield

def anim2():
   for i in range(10):
      self.rect.move_ip(0, 10)
      yield

anims = [anim1(), anim2()]

while playing:
   # handle events
   for a in anims:
      a.next()
   # update screen

I haven't actually used this technique in pygame so I don't know if it's actually helpful here, but I think it's kind of a cool way of simulating threads without threads. Anyone else have experience with designing code this way?

--Mike

Casey Duncan wrote:
You will need a loop that continuously calls methods to update, draw and refresh the screen. At the top of the loop you could check for events to see if you need to do anything. Basically something like:

clock = pygame.time.Clock()
while playing:
    for event in pygame.event.get():
        handle_event(event)
    sprites.update() # update all sprites, including ambient animation
    dirty = sprites.draw(screen)
    pygame.display.update(dirty)
pygame.display.flip() # May not be necessary depending on display config
    clock.tick(40) # Limit to 40 fps (set this to whatever you like)

You can also be kinder to the system by inserting a short time.sleep() in there, but I'll leave that as an exercise for the reader ;)

-Casey

On Sep 21, 2007, at 11:19 AM, Samuel Mankins wrote:

Hi.
Is there a way to pause one function, but to keep all the others going? I'm building a 2D RPG, and my current animation function uses pygame.time.wait(), which is good, but means I can't have "ambient" animations (Things that move around randomly, like plants waving in the wind), and I can only have on going at a time. Does anyone know a way around this?

Thanks!