[haiku-appserver] Re: Overlay support

  • From: "Rudolf" <drivers.be-hold@xxxxxxxxxxxx>
  • To: haiku-appserver@xxxxxxxxxxxxx
  • Date: Sat, 22 Apr 2006 12:51:22 +0200 CEST


> Yeah, now that the app_server is done and stable ;-P
Cool :)

> Well, I still don't see the purpose, though. All that matters are 
> overlay channels - and those you get by calling B_ALLOCATE_OVERLAY. 
> This one should just fail if there aren't any more channels to give 
> away.
Well, it's the same mechanism as with acc engines! There is also a hook 
for this, or am i mistaken?

> > BTW: please remember to ask for the hooks after every new mode 
> > set... 
> > (just like as it is with acceleration hooks)
> I don't think this make any sense. The overlay buffers are created 
> when 
> the bitmap is created - they will stay there no matter what display 
> mode is currently shown.
No, they will be deleted, and recreated after the modeswitch: courtesy 
of app_server. The applications gets informed about modeswitches via 
special messages sent by the app_server (try to locate them, they 
Although no mediaplayer ever yet actually implemented this, and this is 
(also) the reason Be's mediaplayer tends to crash on modeswitches 

> They will also keep there overlay channel as long as they want. The 
> only hook that would make sense to ask again for is 
> and B_GET_OVERLAY_CONSTRAINTS. The other hooks just must stay the 
> same 

The overlay channel is also released and -re-aquired on modeswithces. 
IT really must be done, since the memory map inside the drivers can 
change drastically because of modeswitches: buffers will almost 
certainly NOT be recreated at the same locations.


Other related posts: