Re: [pygame] Wii Remote support -- first patch

[Alex Holkner <aholkner@xxxxxxxxxxxxxx>]

On 26/04/2007, at 7:45 AM, Luke Paireepinart wrote:

> Dave LeCompte (really) wrote:
> > René Dudfield <renesd@xxxxxxxxx> suggested:
> >
> >
> > > For pygame integration posting events into the event queue would  
> > > be a
> > > good idea ( pygame.event.post ).  Maybe run in another thread, or
> > > polled at the required frequency with pygame.time.set_timer ?
> >
> > I'd suggest not creating another thread if we don't absolutely  
> > need to.
> Does anyone know how the mouse works in Pygame? how is it polled?
> I'd think the wiimote should be done in a similar manner.

Events appear in the Windows event queue (and equivalent on other  
platforms).   "Polling" this simply means checking if the queue is  
empty.

> > I haven't dug around very much inside the code, so I don't know  
> > how it
> > looks in there, but it seems like the pygame.event.pump code is  
> > already
> > doing periodic input work,
> Are you assuming that the user calls pump, or does pygame have some  
> internal thread that consistently calls pump?
> or does pygame.event.get call pump as well?

The other pygame event methods (get, peek, poll...) call the SDL pump  
themselves, there is no separate thread.  On the SDL side of things,  
SDL_Pump just pulls events off the Windows event queue (or  
equivalent) and places the matching SDL events on the SDL event queue  
in their place.

There's no way to hook into the SDL pump function, so you'd need to  
be asking the user to pump it from their own event loop.

From your wiimote pump function, it's up to you how you decide to  
post events.  On Windows your overlapped IO idea sounds fine, if  
complicated; Mac and Linux don't have the same overlapped I/O  
interface though (a simpler read with timeout).

I would personally prefer if your wiimote library wasn't tied in  
directly with Pygame (by posting its events into the Pygame/SDL event  
queue), but instead provided an equivalent poll(timeout=None)  
function.  This would allow it to be used with other windowing  
libraries, and you could still provide a Pygame wrapper around the  
poll function for ease of use within Pygame.

Cheers and good luck
Alex.