[haiku-development] Re: Where should video driver test for sufficient memory?

Am Mittwoch, den 17.12.2008, 11:11 -0500 schrieb Gerald Zajac:
> Stephan Aßmus wrote:
> > I think checking in SetDisplayMode() is the best option.
> >
> >   
> The S3 driver currently checks for sufficient memory in 
> SetDisplayMode();  thus, I will leave that unchanged;  however, I will 
> change the error code to B_NO_MEMORY when it detects insufficient frame 
> buffer memory.  Currently, it uses the error code B_ERROR.
> 
> > Sorry that I have not yet fixed app_server. I don't remember if I
> > mentioned this already, but
> > src/servers/app/drawing/AccelerantHWInterface.cpp has a #define at a
> > central place somewhere (in SetMode()?) that turns off the double
> > buffering behaviour. It's supposed to detect the failing and fall back
> > to single buffer. Maybe you can even find out where the error is
> > there... but at least you should be able to work around the issue by
> > switching the #define for the time being.
> >
> >   
> I looked at the code in AccelerantHWInterface.cpp, and it appears to use 
> double buffering for only 32 bit color;  thus, to avoid this problem 
> when testing a video driver, I can use 16 bit color.  Since I hope to 
> have the code for handling ATI Mach64 chips working soon, I can avoid 
> this problem by using 16 bit color when testing those chips.  Most of 
> them have 2, 4, or 8 MB's of memory;  thus, this problem would certainly 
> occur when testing those chips.
> 
> When do you think this problem in the app_server will be fixed?

I have no idea, really, as I am pretty busy with work right now and
don't really know when I will find more time for Haiku again. If it
really holds you up, I suggest again that you take a look at
AccelerantHWInterface::SetMode(). It should really not be hard to fix,
the intention is to retry setting the mode when it failed with double
height and try again with regular height.

Best regards,
-Stephan

Other related posts: