Re: [AD] al_update_display_region

[Evert Glebbeek <eglebbk@xxxxxxxxxx>]

On 26 feb 2009, at 13:42, Elias Pschernig wrote:
> You never have to deal with expose events - X11 just (at least in the
> default configuration) does not keep a back buffer with the window
> contents. So as soon as you stop constantly redrawing the window it  
> will
> look broken.

Hmm. That's annoying.
Is there a flag one can set to change that?

> This has nothing to do with the reason ex_expose fails btw, also other
> examples who request a 32-bit buffer with no alpha will fail. And I
> assume it will fail on all platforms as the scorer is platform
> independent now.

ex_expose works on OS X in the sense that it runs fine. I don't see  
expose events being triggered though, which is odd because I thought I  
added that.
I'm also quite sure it doesn't use the AllegroGL mechanism to pick the  
best mode (I also don't see how that would work, given that as far as  
I can tell at least the OS X port's implementation is very different  
from the X11 one, but I haven't looked into this in great detail).
Note though that OS X has its own mechanism for picking the best mode:  
you give it the list of options you want and tell it to either give  
you exactly that, or you tell it to set the closest match that it can.
At the moment, this is handled a bit crudely by the code: if some  
options are required, it requires all of them and doesn't try to toss  
out some of those that don't work if the mode set fails. Not that I've  
seen that happen.

Evert