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

[Glynn Clements]

Bob Covill wrote:

> > > 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.

Agreed. If wxPython is used for a new interface, the core Python
libraries include XML parsing.

> > 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.

Personally, I'd suggest using an interpreted language for programs
which are primarily user interfaces. It makes it much easier for users
to add tweaks for their specific needs. FWIW, wxPython includes a
GLCanvas class (analogous to Togl).

Do you have any code available? In terms of replacing NVIZ, it would
be useful to have a relatively simple example of how to use the OGSF
library; NVIZ itself is far too complex for that.

-- 
Glynn Clements <glynn at gclements.plus.com>