Re: OT: GUI

[Stephen Leake <stephen_leake@acm.org>]

"Martin Dowie" <martin.dowie@btopenworld.com> writes:

> "Preben Randhol" <randhol+valid_for_reply_from_news@pvv.org> wrote in
> message
> news:slrnc7sr4a.15k.randhol+valid_for_reply_from_news@rong.nt.ntnu.no...
> > On 2004-03-27, Martin Dowie <martin.dowie@btopenworld.com> wrote:
> > > "Jacob Sparre Andersen" <sparre@nbi.dk> wrote in message
> > > news:plptaz2ntn.fsf_-_@sparre.crs4.it...
> > >> But would that be any better than GtkAda?  Just another non-native GUI
> > >> library.
> > >
> > > Well, Claw is atleast native on Win32 platforms - is Gtk(Ada) native on
> > > anything? I don't mean to be rude, I really just don't know!
> >
> > What is your definition of native? Is Ada native on anything or should
> > one use assembly?
> 
> Native as in not having to go through a large binding to access the
> underlying opertion. Claw is "native" as it sits (almost) directly on top
> of the Windows calls. 

Yes. But Claw is itself a "large binding". So are applications written
using Claw "native windows"?

I think this is a moot point. The issue is what is gained by a native
binding. Usually, the desired gains are execution speed, and ease of
porting other "native" applications.

Any thick binding will be slower than a thin binding, but some are
slower than others. Gtk is noticably slower than Windex, and I suspect
than Claw.

Ease of porting will always be low, between any two thick bindings;
porting an app from Windex to Claw is probably as hard as porting from
Windex to GtkAda.

> But GtkAda on Windows isn't native as it doesn't use the underlying
> OS GUI routines 

Of course it does!

> (or at least not in any way that could be described as close).

Well, that's the whole issue, isn't it? What, exactly, do you mean by
"close".

Let's see, we could measure the number function calls. Suppose I do
'Set_Text (widget, "foo");' in Windex, Claw, and GtkAda. How many
function calls does that go thru before it gets to Win32 API Settext?

Well, Windex.Windows.Edit_Text.Put_Text is a direct binding to Win32
API Send_Message (WM_SETTEXT). I guess that's pretty "close".

I'm not familiar enough with the Gtk source to actually trace this. I
bet it is more calls, though.

But then, if I resize a window, and want all the child windows to
automatically resize to fit, GtkAda is _way_ more efficient than
Windex, because it is already done, and it "just works"; any code I
write to do the same thing will not be as good. No binding that
provides that feature will be "close" to the Win32 API.

So it depends heavily on what features you measure, to get a
definition of "close".

-- 
-- Stephe