From: Rodolphe Ortalo <ortalo@laas.fr>
  To  : ggi-develop@eskimo.com
  Date: Wed, 19 Aug 1998 12:27:03 +0200

Re: LibGGI3D RFC

[I don't quote anything from former posts, because I guess
 everyone read them, and they are long...]

Well, first, let's say I'm glad of the way this RFC was written and
commented. I'm also glad that Jon did this first try... (In other words,
thanks for the work ;-)


I tend to agree with the overall design of Jon. And I also tend to
agree with the comments Scott McNab made.

To summurize my views (with Jon's proposal as the basis):
 - I don't really feel the need for having a notion of camera in
libggi3d. I would be happy with simple 2D parameters in libggi3d
(in fact, projected 2D parms, plus 1/Z, U,V, etc...)
 - I think that Z-buffer wouldn't be so annoying to manage.
Jon does not seem to have the same view, so, could you point the things
that worry you on this point Jon ?
 - I also think alpha management could be very useful and not so
difficult... (Same comment as previous point.)
 - I want clipping in libggi3d also.
 - I am not yet completly clear of how you want to manage textures ?
What about texture cache management also ? You associate that to
a particular shader, that's the idea ? BTW, I tend to like that idea
of registering & using shaders like you proposed.

Sorry for stating opinions without explaining them, but I lack
time currently, and I don't really want to know why we should
have this or this feature, I would like to know why we should
NOT have this or this feature...

These are only direct opinions of course. I know these opinions are
biased a lot by the specific hardware I've worked with...
Once again, let me mention the fact that the Cirrus Logic Laguna 3D
(CL-GD5464 or CL-GD5465) is pretty clear on these issues and that
the documentation _is_ available:
 (6,8 Mo) http://www.cirrus.com/ftp/pubs/gd5465trm.pdf
(see also: http://www.cirrus.com/products/overviews/gd546x.html
 for general info)

A side effect of this hardware background is: what about fog,
transparency ? (other shaders ?)

It's not the Voodoo of the G200, but it may be useful as I find in
this chipset a clear mapping with libggi3d as currently discussed.

Maybe the next step is to try to propose an API no ? (Sure, it will
not be the final API, but it will delimit the target.)

Rodolphe