[GRASS-dev] NVIZ state file format (was GRASS6.3 on Windows, nviz)

[Bob Covill]

On Wed, 2007-08-29 at 08:32 -0700, Michael Barton wrote:
> 
> 
> On 8/28/07 12:09 PM, "Dylan Beaudette" <dylan.beaudette at gmail.com> wrote:
> 
> > On Tuesday 28 August 2007 11:43, Michael Barton wrote:
> >> AFAICT, the current situation is that NVIZ will not properly read the state
> >> file that it writes. To 'fix' it to read it with the current file format
> >> and code approach will result in an incomplete 'fix' in that it still won't
> >> read parts of the state file properly.
> >> 
> >> XML is a potentially good idea, but requires an external library AND I
> >> don't know XML well enough to implement this.
> > 
> > My 2 cents here. If we are using XML in other parts of GRASS (via external
> > parsing libs) I think that it would be good to standardize on some flavor of
> > XML for any misc. things like the NVIZ state file. XML is simple to read in a
> > text editor, simple to parse with external tools, and simple to read/write
> > with the appropriate libs.
> > 
> snip snip ...
> > 
> > thats the kicker... I do not know enough about XML in a C environment to do
> > this / and a MS thesis is looming over my head right now... Sorry!
> > 
> 
> Indeed! Summer is over and my time is short too.
> 
> Unless someone that does have expertise in XML and time to do it is out
> there, I propose to fix this with minimal changes in the current, simple
> ascii state file for the upcoming 6.3 release.

If there is an easy fix, you may as well apply it for the upcoming
release. There is probably no point in adding an XML parser to the TCL
interface, as its days are probably numbered.

> We should rethink this for any subsequent releases, including 7. I don't
> want to keep saying that we'll do it better in wxPython, but there are
> available xml parsers there (e.g., SAX) that would make this easier. But
> again, it will depend on available expertise.
> 
A number of UI's (GTK(glib), C#, ...) have their own XML parser which
could be taken advantage of when nviz is moved to a new interface. As a
proof of concept I have been playing around with the OpenGL GTK
interface GtkGLExt ( http://www.k-3d.org/gtkglext/Main_Page ) to view
and navigate GRASS data via ogsf. It works fine.

--
Bob