Re: [Fresco-devel] Some questions

Nicolas Souchu <[email protected]> wrote:
[...]
> Not exactly. To detail a bit Nick's statement, X protocol management may
> be separated from HW drivers. like window managers are separated from
> drawing routines.

It may, yes.

> X11 is one X protocol. XFree is one of X11 implementations
> and finally, not the least, XFree86 adds to XFree the driver infrastructure
> for HW control, originaly for i386 machines but now for other I guess.

It would be great if someone would be able to get the drivers out of
XFree. Unfortunately those are supposed to rely heavily on XFree
internals:-(

[...]
> If Fresco performs 3D oriented calls, otherwise, how can you use X11 3D?

Fresco runs on top of either GGI or SDL, two libraries able to address
the display hardware. Both can render directly to the framebuffer or to
a window on an X-server.

Fresco further can output to either pixels (via LibArt), Postscript or
OpenGL. If you output to OpenGL and have SDL render that on top of X you
get the same acceleration as any other X application.

Once SDL or GGI get 3D acceleration going on the framebuffer we'll just
use that. We don't need to change our code for that: Both SDL and GGI
hide that 'detail' from us.

What if some other library beats them with HW acceleration on the
framebuffer? We'll just support that as well (we used to have support
for DirectFB, GLUT and CAVElib in addition to GGI and SDL a while back).
It's not that hard to do:-)

> [...]
> > You mention drop shadows, which are nice eye candy and fit rather nicely 
> > in Fresco, even though we can't actually draw them yet. A drop shadow is 
> 
> But such drawing effects are pixel oriented and not vectors. Isn't that in
> contradiction with Fresco capacities?

How so? A gradient is more vectorbased then pixelbased in my
understanding.

[...]
> > One of the goals of the Fresco project is to provide a framework for 
> > user interface experimentation. This means at least two things, one good 
> 
> experimentations... which kind? Programming or using of computer resources?

We mostly use design patterns. Those are described in a book from 1994.
Hardly cutting edge in the computer programming world;-)

What we do is experiment with HCI (human computer interaction). One thing
that allways draws attention on shows is rotated windows. Most people just
complain about that being a waste of resources... (actually it is very hard
for us to have windows that can't be rotated!). One of the visitors was
very enthusiastic about that feature though: "Hey, that's great! Let's put
the quit button on the backside of the window. I keep hitting that damn
button accidentally all the time. Maybe add some information like CPU usage
of the process controlling the window, etc. too while you are at it." I'm
not saying that this is a killer feature, but I think it is a very nice
example for something that couldn't be done before... I'm sure there are
much more things possible with fresco that can improve the way we
communicate with that damn box in front of us.

[...]
> If I understand correctly, Fresco can take advantage of 2D acceleration a
> lot more than XFree and even in network remote environments?

2D and even 3D acceleration. Yes, this works fine over the network too.
The bandwidth usage is minimal. The demo's we have take about 1.9kbit/s
(after the initial setup phase), independent of wether someone interacts
with the windows or not. Exporting the same demo via VNC takes up about
800kbit/s when interacting with the windows.

-- 
Gruss,
Tobias

------------------------------------------------------------
Tobias Hunger           The box said: 'Windows 95 or better'
[email protected]                      So I installed Linux.
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