Native surface creation

[Jon Smirl]

On Fri, 11 Mar 2005 15:48:48 -0700, Brian Paul
<brian.paul at tungstengraphics.com> wrote:
> Jon Smirl wrote:
> > I'm trying to make sure that XGL doesn't have to run as root. This
> > implies that you can't set an arbitrary mode. That's the purpose of
> > the list of modes names that you can then copy to 'mode'.
> >
> > However, the list of mode name is created from a hotplug event that
> > runs as root. Right now the user space app builds the list of names
> > from EDID but it is intented to also merge in custom modes from
> > /etc/fb.modes. So if you want 1184x888 at 77Hz add it to fb.modes and
> > reload the fbdev driver. That will cause1184x888 at 77Hz to now appear in
> > the mode list and a normal user can then select it.
> 
> So "184x888 at 77Hz" is a concrete example of a mode name?  Will that
> syntax be extensible?

They are just human readable strings. You could name the mode orange.
After the mode is set you can query all of the details with an ioctl.

> Suppose I want to do active stereo (i.e. alternate display of
> left/right color buffers in sync with LCD glasses).  How would I name
> a mode that supported stereo?
> 
> At the EGL API level, we'd probably have an opaque EGLMode handle and
> a function for querying the mode's attributes (ala
> eglGetConfigAttrib), another function for querying the available
> modes, etc.
> 
> That's not in conflict with what you're doing, of course.  The
> translation would be done in the EGL library.
> 
> 
> > As for picking the mode, why bother with the closest match function.
> > Why not just give them a list of mode names and let them pick?
> 
> Well, either the user writes a search function or we offer one in the
> EGL API.  I think a mode picking function similar to eglChooseConfig()
>   would be most consistent

There is already a search function in fbdev but it is not exposed in
an ioctl. What is a case where executing an app should force a mode
change that isn't under user control?
> 
> -Brian
> 


-- 
Jon Smirl
jonsmirl at gmail.com