Re: Hardware accelerated 2D graphics (with gtk-osx)

[Kristian Rietveld <kris gtk org>]

On Aug 8, 2010, at 9:32 PM, John Emmas wrote:
> On 1 Aug 2010, at 21:49, Kristian Rietveld wrote:
>
> > GTK+ OSX does all drawing using CoreGraphics, this should be hardware-accelerated whenever possible.
>
> From what I've been able to tell, CoreGraphics eventually ends up using QuartzGL for 2D imaging and 
> acceleration.  QuartzGL however seems to be buggy, unfinished and badly written.  On my system (and I 
> suspect most other Macs) enabling hardware acceleration for QuartzGL actually worsens 2D graphics 
> performance rather than enhancing it.

What hardware and OS revision are you using?  Do you experience this just in your canvas or in other GTK+ 
applications as well?  I am wondering if there's a certain code path that is badly optimized?

The slowness you are observing is interesting, since the graphics performance of GTK+-OSX on my Mac laptop is 
faster than the performance of GTK+-X11 on my (faster) Linux desktop.

> So another option might be to use gtk-x11 in the Mac build, instead of gtk-osx.  Obviously this would 
> require an X server to be installed but I don't think that's too difficult on a Mac.  The question is 
> whether or not X (under OS-X) also uses QuartzGL or whether it interfaces with Quartz Compositor directly 
> (or via some alternative technology, such as OpenGL).  I'm assuming there must be an interface to Quartz 
> Compositor at some stage.

Mac OS X actually ships with an X11 server (X11.app), you can install it from the extra components on the Mac 
OS X installation DVD.

> Anyone know where I could find out some more information about X server for OS-X?

I guess this will be of interest:  http://xquartz.macosforge.org/trac/wiki


regards,

-kris.