From: Marcus Sundberg <e94_msu@e.kth.se>
  To  : ggi-develop@eskimo.com
  Date: Fri, 17 Jul 1998 17:54:52 +0200

Re: GGI_AUTO

Andrew Apted wrote:
> 
> Marcus writes:
> >  0 is an absolute neccesity when we're dealing with graphtypes, as
> >  graphtypes are made up of several bytes of info. If GGI_AUTO is
> >  -1 you can't do (GT_TRUECOLOR | GGI_AUTO) ...
> 
> Apart from "give me absolutely any mode" (for which -1 will do), is there
> a big need for a constant ?  In the above case, just plain GT_TRUECOLOR
> could be used.  Some other examples: (GT_INDEX | 8), (GT_TRUECOLOR | 16),
> (GT_TRUECOLOR | (32 << GT_ACCESS_SHIFT)).

GT_CONSTRUCT() needs to have a zero in the "don't care fields".
And there might come a time where we regret it if we allow
users to make graphtypes by hand. Especially when it comes to
things like (32 << GT_ACCESS_SHIFT).

> And there's still the
> previous values (GT_8BIT and the rest -- or are we phasing them out ?).

I think we should keep them. Users need a simple solution
to get started with a new API, and GT_8BIT and friends
are just that.

> I'm thinking that we don't need a constant.  What do you think ?

We need it for GT_CONSTRUCT at least.
But I still think we should have GGI_AUTO == 0 ;)

//Marcus